JPH06235489A - Joint mechanism of pressurizing tube - Google Patents

Abstract

PURPOSE:To provide a joint mechanism to connect a pressurizing tube used for internal pressure moulding to a pressure source, which is extremely easy to connect and disconnect and douse not cause pressure leakage. CONSTITUTION:A coupler system is constituted of a nozzle 10 having an annular projection part 11 on its tip, a dividable sleeve 21 to compressively fasten a swelling part 32 of a pressuring tube 30 swollen as this annular projection part 11 is inserted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint mechanism for a pressure tube. In particular, the present invention relates to a joint mechanism that connects a pressure tube used for internal pressure molding and the like with a pressure source, is easily removable, and does not cause pressure leakage.

[0002]

2. Description of the Related Art The technique of internal pressure molding is generally known as one of synthetic resin molding methods. For example FRP or F
When manufacturing a racket frame made of RTP, a rubber or silicone pressure tube is inserted into the hollow part of the FRP or FRTP prepreg molded into an elongated hollow body, and the prepreg is separated from the upper mold and the lower mold. Set to a flat mold, heat the mold, introduce pressure fluid such as compressed air into the pressure tube, and expand the pressure tube to press the prepreg against the inner wall of the mold to cure. Has been. By this internal pressure molding method, a product having good surface smoothness and having no sink mark or void can be obtained. This pressurizing tube has one end sealed for pressurization, and the other end has a nozzle extending from a pressure source inserted therein. However, if this nozzle is simply inserted into the pressure tube, it will be pushed out as the internal pressure rises when the pressure fluid is introduced, and will eventually fall out of the pressure tube.
In addition, the pressure fluid may leak due to the widening of the gap between the pressure tube and the nozzle. In order to prevent such "pressure leakage", conventionally, the portion of the pressure tube in which the nozzle is inserted is tied from the outside with a string or the like, or wound with tape and fixed by pressure.

[0003]

Since all of the conventional nozzle fixing methods as described above are carried out manually, not only a large number of man-hours are required and work efficiency is poor, but also when the nozzle is not tightly pressed, the nozzle is pressed. The process was unstable, such as sudden pressure leakage during molding. A reliable method for clamping the nozzle is to provide an annular convex part with a diameter larger than the inner diameter of the pressure tube at the tip of the nozzle, insert this part deeply into the pressure tube, and then press the nozzle There is a method of tightening and fixing with a fastening band or the like from around the portion where the tubular body portion is inserted. Although this method is more reliable than the method of tying with a string as described above, the tightening of the fastening band is still done manually, so that there remains a problem in work efficiency. The present invention has been made to solve this problem. Therefore, it is an object of the present invention to provide a joint mechanism for a pressure tube that can be easily attached and detached and that does not cause pressure leakage during a molding operation.

[0004]

SUMMARY OF THE INVENTION The above-mentioned problems can be resolved by surrounding a nozzle extending from a pressure source and inserted into an end portion of a pressure tube, and a nozzle insertion portion of the pressure tube into which the nozzle is inserted. The nozzle has an annular convex portion formed at the tip end thereof with a diameter larger than the inner diameter of the pressure tube, and the inner wall of the sleeve is bulged by inserting the annular convex portion. The problem can be solved by providing a joint mechanism for the pressure tube, which is formed to have a smaller diameter than the outer diameter of the ridge of the pressure tube, whereby the ridge of the pressure tube is pressed and clamped by the nozzle. In the above, it is preferable that the inner wall of the sleeve is formed to have a gradually smaller diameter toward the pressure source side. In the above, the sleeve is preferably formed integrally with a mold for internal pressure molding.

[0005]

The joint mechanism of the present invention is a joint mechanism for connecting the end portion of the pressure tube used for the internal pressure molding and the pressure source. This joint mechanism is composed of a nozzle having an annular convex portion at the tip and a separable sleeve that presses the raised portion of the pressurizing tube into which the annular convex portion is inserted and is raised. Since the inner wall of the sleeve is formed to have a smaller diameter than the outer diameter of this raised portion, the pressure tube, which is an elastic body, is strongly pressed between the annular convex portion and the sleeve in this portion, exerting a packing effect and exerting a compression effect. In addition to preventing leakage, strong frictional resistance also prevents the nozzle from falling off. At this time, if the inner wall of the sleeve is formed to have a gradually smaller diameter toward the pressure source side, when the nozzle is pressed toward the pressure source side by the internal pressure, the raised portion is formed in the gradually narrowing gap between the annular convex portion and the sleeve. As it is pushed in, the pressure leakage prevention effect is enhanced. Since the sleeve is separable, it is very easy to put on and take off. For example, if the sleeve is divided and each piece is molded integrally with the upper and lower flat mold pieces for internal pressure molding, insert the nozzle into the pressure tube attached to the prepreg, When this prepreg is set in the lower mold and the upper mold is overlaid, the sleeve is also formed at the same time, so that the joint mechanism can be attached and detached substantially only by attaching and detaching the nozzle, and the working efficiency is significantly improved.

[0006]

Embodiments of the present invention will be described with reference to the drawings. (Embodiment 1) FIG. 1 shows an embodiment in which a sleeve is integrally formed with a flat mold for internal pressure molding. In the figure, reference numeral 1
Reference numeral 0 is a nozzle, 20a and 20b are flat upper and lower dies, 21a and 21b are respective pieces of a sleeve, 30 is a pressure tube, and 40 is a prepreg. Here, in the joint mechanism of the first embodiment, the nozzle 10 and each piece 21a of the sleeve,
21b.

The nozzle 10 has an annular convex portion 11 at the tip of the cylindrical portion inserted into the end portion of the pressure tube. The diameter of the annular convex portion 11 is equal to the inner diameter h of the pressure tube 30.
It is molded to a larger diameter. In addition, the nozzle 10 is provided with a stop ring 13 at a predetermined position of its tubular portion. Each piece 21a, 21b of the sleeve is formed integrally with each piece 20a, 20b of the mold so that the sleeve is formed when the upper and lower molds 20a, 20b of the flat mold are stacked. (The formed sleeve is indicated by reference numeral 21 below). The sleeve 21 is arranged at a position surrounding the nozzle insertion portion 31 of the pressure tube. The inner wall of the sleeve 21 is formed to have a diameter smaller than the outer diameter S of the raised portion 32 of the pressure tube that is raised by inserting the annular convex portion 11 of the nozzle. As a result, FIG.
As shown in (b), when the annular convex portion 11 is inside the sleeve 21, the raised portion 32 is pressed from the surroundings and clamped by the nozzle 10. Mold 20a, 20b
Stoppers 23a and 23b are provided at the end portions of the positions where they are engaged with the stop ring 13 of the nozzle.

Next, an example of the attachment / detachment operation of this embodiment will be described. In advance, the silicone pressure tube 30 is inserted into the hollow portion of the FRP prepreg 40 formed in the shape of an elongated hollow body. One end of the pressure tube 30 is sealed, and the other open end is pulled out from the end of the prepreg 40 by a certain length. As shown in FIG. 1A, the nozzle 10 is inserted into the end of the pressure tube 30 that has been pulled out until the end contacts the stop ring 13. The other end of the nozzle 10 is connected in advance to a pressure resistant hose (not shown) of the air compressor. Prepreg 40
Is set in the lower mold 20b. At this time, the nozzle insertion portion 31 of the pressurizing tube is arranged on the concave surface of the sleeve piece portion 21b formed in the lower mold 20b. In this state, the stop ring 13 of the nozzle is in contact with the end surface of the sleeve piece 21b. When the upper mold 20a is overlaid, the sleeve piece 21a formed integrally with the upper die 20a becomes the sleeve piece 21b.
To form a sleeve 21.

The upper and lower molds 20a and 20b are attached to the prepreg 30.
The pressure fluid is introduced into the pressurizing tube 30 through the nozzle 10 while being heated to the curing temperature. When the internal pressure of the pressure tube 30 increases, the pressure tube 30 expands and presses the prepreg 40 against the upper and lower mold surfaces 22a and 22b as shown in FIG. 1
0 is also pressed and slides in the pressure tube 30 toward the pressure source side. In this sliding, the stop ring 13 is the stopper 23.
It is stopped by contacting a and 23b. At this time, since the annular convex portion 11 of the nozzle is moved to the inside of the sleeve 21, the raised portion 32 is pressed by the sleeve 21 and exhibits a packing effect, and is tightly clamped to the nozzle 10. Therefore, in this state, the nozzle 10 may fall out,
The pressure fluid does not leak from between the nozzle 10 and the pressure tube 30.

When the upper mold 20a is removed when the curing of the prepreg 40 is completed, at the same time, the half piece 2 of the sleeve is removed.
1a is also removed. Therefore, the nozzle 10 can be easily pulled out from the end of the pressure tube 30 by hand.

(Embodiment 2) FIG. 2 shows another embodiment of the present invention. Similar to the first embodiment, the sleeve 21 is formed integrally with the upper and lower flat molds 20a and 20b for internal pressure molding. However, the inner wall of the sleeve 21 is formed to have a gradually smaller diameter on the pressure source side, and the stop ring 13 extends from the nozzle.
However, the stoppers 23a and 23b are removed from the mold. The attachment / detachment operation of this embodiment is the same as that of the first embodiment.
However, when internal pressure is applied to the pressure tube 30, the sliding of the nozzle 10 toward the pressure source side proceeds to a certain extent and is stopped because the inner wall of the sleeve 21 is gradually narrowed toward the pressure source side. . Raised portion 32 at this time
Are pressed into the narrow gap formed by the annular convex portion 11 and the sleeve 21, and exhibit a packing effect, and are tightly clamped to the nozzle 10. Therefore, in this state, the nozzle 10 does not fall out and the pressure fluid does not leak from between the nozzle 10 and the pressure tube 30.

It is clear that the joint mechanism of any of the first and second embodiments is extremely simple because it can be attached and detached substantially only by attaching and detaching the nozzle, and it is clear that the nozzle does not drop out or leak during the pressurization. Is.

[0013]

According to the joint mechanism of the pressure tube of the present invention, the nozzle having the annular convex portion at the tip and the splittable sleeve for compressing the convex portion of the pressure tube which is bulged by inserting the annular convex portion. Since it is composed of and, it is very easy to attach and detach, and there is an effect that the nozzle does not drop out or leak during the pressurization.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.
(A) shows a state before pressurization and (b) shows a state during pressurization.

FIG. 2 is a sectional view showing another embodiment of the present invention.
(A) shows a state before pressurization and (b) shows a state during pressurization.

[Explanation of symbols]

10 ... Nozzle, 11 ... Annular projection, 21 ... Sleeve, 30
... pressure tube, 32 ... ridge, h ... pressure tube inner diameter.

Claims (1)

[Claims] 1. A joint mechanism for connecting an end portion of a pressure tube used for internal pressure molding and a pressure source, the nozzle extending from the pressure source and inserted into the end portion of the pressure tube, and the nozzle being inserted. And a splittable sleeve surrounding a nozzle insertion portion of the pressure tube, wherein the nozzle has an annular convex portion formed at a tip end portion thereof having a diameter larger than an inner diameter of the pressure tube, and the sleeve. The inner wall of is formed to have a diameter smaller than the outer diameter of the ridge of the pressure tube that is bulged by inserting the annular convex portion, whereby the ridge of the pressure tube is pressed and clamped by the nozzle. Pressure tube joint mechanism.