JPH0251725B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a curved pipe mold that can be inserted into and removed from a cylindrical rotary mold.

The curved pipe mold is inserted into a cylindrical rotary mold, and a resin tube is centrifugally molded onto the inner circumferential surface of the mold. After the resin tube is pulled out of the rotary mold together with the resin tube, the curved pipe mold is bent to remove the resin inside. The pipe was bent into one piece, and then the bent pipe was extracted from the bending mold. In such a curved tube forming process, the diameter of the curved tube mold is reduced to ensure reliable insertion into the rotary mold, the diameter is expanded due to the centrifugal force during centrifugal molding, and the diameter is contracted when removed from the rotary mold. The diameter of the pipe may be increased, the outer diameter side may be extended when bent, and the diameter may be expanded when the bent pipe is pulled out. In this way, curved pipe molds can expand, contract,
The growth will be repeated. Conventionally, there was no curved tube molding die that could quickly respond to such changes.

The present invention includes an outer mold for a receptacle that can be fitted to one end of the rotary mold, an outer mold for a socket that can be fitted to the other end of the rotary mold, and a rubber mold for a body fixed between the two outer molds. , has a body holding mold arranged in a spiral shape on the outside of this rubber mold for the body, the body holding mold is cut at one point in the circumferential direction, and an expansion joint is inserted between the cut ends. The present invention provides a curved tube forming mold characterized in that the tubes are connected together, and with this configuration, it is possible to quickly respond to changes such as diameter expansion, diameter contraction, and elongation.

Hereinafter, one embodiment of the present invention will be described based on the drawings. In FIG. 1, reference numeral 1 is a cylindrical rotating type, which is supported by a plurality of wheels 2 and is rotatable around a horizontal axis 3. In FIG. Reference numeral 4 denotes a ring-shaped outer mold for a receptacle that is fitted onto one end of the rotary mold 1, and 5 is a ring-shaped outer mold for a socket that is fitted onto the other end of the rotary mold 1. Ring-shaped end face molds 6 and 7 are fitted into both outer molds 4 and 5, respectively. Reference numeral 8 denotes a socket inner surface regulating device that fits inside the end face mold 6 on the socket side and is movable in the direction of the horizontal axis 3. By projecting inward with respect to the end face mold 6, the inner periphery of the molded socket part is adjusted. Cover the surface. 9
is a rubber mold for the trunk disposed between both outer molds 4 and 5, and is formed by thick walled portions 9a and 9b at both ends and a long middle thin walled portion 9c, with the thick walled portions 9a and 9b at both ends corresponding to each other. It is fixed to the outer molds 4 and 5 via fasteners 10 and 11. The inner diameter of the outer mold 4 for the socket is the same as that of the rubber mold 9 for the body.
The inner diameter of the body rubber mold 9 on the side of the outer mold for the socket is formed into an inclined cut surface 9d. Furthermore, the inner diameter of the outer spout mold 5 is smaller than the inner diameter of the rubber mold for the body 9, and the inner surface of the outer mold for the spout 5 on the side of the rubber mold for the body is formed into an inclined cut surface 5a. ing. 1 to 3, reference numeral 12 denotes a spiral body holding mold disposed outside the intermediate thin wall portion 9c of the rubber mold 9 for the body portion, and is wound spirally around the outside of the intermediate thin wall portion 9c. It consists of a plate plate 13 and a spiral rib plate 14 protruding from the outside of the plate plate 13. Adjacent spiral edges of the plate plate 13 are connected by a wrap structure 15 that allows movement within a certain range in the direction of the horizontal axis 3, and the outer surface of the rib plate 14 is in contact with the inner surface of the rotary mold 1. do. One location in the circumferential direction of the body holding mold 12 is cut in three directions along the horizontal axis, and each cut end of the rib plate 14 is connected via an expansion joint 17 with a cut portion 16 in between. . As shown in FIGS. 4 and 5, this expansion joint 17 is fixed to one cut end and has a pair of elongated holes 18 and 19.
a first link plate 20 having a first link plate 20 and a first link plate 20 fixed to the other cut end and having a pair of elongated holes 21 and 22;
The link plate 23 is fixed to the outer inner surface of the elongated hole 18 of one of the first link plates 20 and the second link plate 23
The first receiving member 24 passes through one long hole 21 of the
and a second receiving member 25 fixed to the outer inner surface of the other elongated hole 19 of the first link plate 20 and passing through the other elongated hole 22 of the second link plate 23; A third receiving member 26 is fixed to the inner inner surface of the hole 21 and passes through one of the elongated holes 18 of the first link plate 20; The fourth receiving member 2 passes through the other elongated hole 19 of the link plate 20
7, a first tube 28 disposed through the first receiving member 24 and the third receiving member 26, and a first tube 28 disposed penetrating between the second receiving member 25 and the fourth receiving member 27. Each receiving member 24 to 27 is formed in the shape of a half pipe, and both tubes 28 and 29 are also used in each expansion joint 17 portion.

First, centrifugal molding will be explained. As shown in the upper half of the horizontal axis 3 in FIG.
5, body holding mold 12, etc., and with the receptacle inner surface regulating device 8 removed and moved, the receptacle part 30 is centrifugally molded to the end face mold 6 and the receptacle outer mold 4. Then, as shown in the lower half of the horizontal axis core 3 in FIG. The body portion 31 is centrifugally formed over the following steps. Next, the socket part 30 and the body part 3
1 is in an uncured state, everything is taken out from the rotary mold 1, and the state shown in FIGS. 2 and 3 is obtained. Then, the plastic working part is curved so that the cut part 16 is on the curved upper surface side. At this time, the presence of both outer molds 4 and 5 prevents deformation of the receptacle portion 30 and the spigot portion, and the intermediate curvature is facilitated by the movement of the adjacent portions of the plates 13 by the wrap structure 15. It will be held in After curving and curing, demolding is performed.

That is, as shown in FIG. 8, the mold 6 for both end surfaces,
7 is removed together with the socket inner surface regulating device 8. Then, the push tool 32 is fitted into the outer mold 5 for the spigot and brought into contact with the end surface of the spigot. Next, the lid 33 is fitted into the outer mold 5 for the receptacle, and is locked with the pin 34 and the hook 35. In this state, press tool 32 and lid body 3
A fluid (air, etc.) is supplied from a fluid supply pipe 37 to a space 36 formed by 3 and 3. Then, fluid pressure acts on the end face of the receptacle through the pusher 32, thereby causing the receptacle to be pulled out. The fluid pressure (internal pressure) also acts in the direction of inflating the rubber mold 9 for the trunk, and promotes demolding. During such demolding, the tube is prevented from popping out. That is, a case 38 is attached to the outside of the lid body 33, and the rotating shaft 3 is installed inside this case 38.
A reel 40 is disposed via 9. Further, the end of the wire 41 wound around the reel 40 is coupled to the pusher 32. Therefore, by letting out the wire 41 little by little during demolding, it is possible to prevent the wire 41 from popping out.

During the above steps, the curved pipe mold is contracted and expanded in diameter. That is, when reducing the diameter, as shown in FIG. 6, fluid is supplied to the second tube 29 to inflate it. As a result, the second receiving member 25 and the fourth receiving member 27 are moved apart from each other, and one end of the rib plate 14 that is integral with the second receiving member 25 is connected via the first link plate 20 to the second receiving member 23 . Fourth
The receiving member 27 and the other end of the integrated rib plate 14 are moved toward each other. Therefore, both ends of the rib plate 14 are at a certain distance from the non-pressure state shown in FIG.
l is moved closer _{one by one} , and the entire diameter is reduced. Further, when expanding the diameter, fluid is supplied to the first tube 28 to inflate it as shown in FIG. As a result, the first receiving member 24 and the third receiving member 26 are moved apart from each other, and one end of the rib plate 14 that is integrated with the first receiving member 24 is connected via the first link plate 20 and the second link plate 23 is moved. As a result, the third receiving member 26 and the other end of the integrated rib plate 14 are moved apart. Therefore, both ends of the rib plate 14 are moved away from each other by a certain distance l ₂ from the unpressurized state shown in FIG. 4, and the diameter of the entire rib plate 14 is expanded.

According to the curved pipe mold of the present invention, due to the presence of the expansion joint, it is possible to quickly respond to changes such as diameter expansion, diameter contraction, and elongation, and it is possible to provide a mold that is easy to use.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a longitudinal sectional front view during centrifugal molding, and FIG. 2 being a front view during extraction.
Fig. 3 is a sectional view taken along line A-A in Fig. 2, Fig. 4 is a cross-sectional plan view of the main part, Fig. 5 is a side view of the same, Fig. 6,
Figure 7 is a cross-sectional plan view of the main parts showing the operating state;
The figure is a longitudinal sectional front view during demolding. 1...Rotating mold, 4...Outer mold for receptacle, 5...Outer mold for spigot, 9...Rubber mold for body, 12...Body holding type, 13...Plate plate, 14...Rib board,
15... Wrap structure, 16... Cutting portion, 17...
Expansion joint, 18, 19... Long hole, 20... First link plate, 21, 22... Long hole, 23... Second link plate, 24... First receiving member, 25... Second receiving member , 26... Third receiving member, 27... Fourth receiving member, 28... First tube, 29... Second tube.

Claims (1)

[Claims] 1 A curved pipe mold that can be inserted into and removed from a cylindrical rotary mold, comprising an outer mold for a receptacle that can be fitted to one end of the rotary mold, and a receptacle that can be fitted to the other end of the rotary mold. An outer mold, a rubber mold for the body fixed between both outer molds,
A body holding mold is arranged spirally on the outside of this rubber mold for the body, the body holding mold is cut at one point in the circumferential direction, and the cut ends are connected via an expansion joint. A curved pipe mold characterized by being connected.