JPH0249614B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method of manufacturing a coiled lightweight core material for reducing the weight of a ring-shaped rim portion of a steering wheel and obtaining a highly rigid ring reinforcing body.

[Prior art]

Conventionally, this type of ring reinforcing body has been disclosed by the applicant in Japanese Patent Application No. 59-79589 (Japanese Unexamined Patent Publication No. 60-222235).
The present invention is proposed in the method for manufacturing a steering wheel shown in Japanese Patent Publication No. That is, as shown in FIG. 11, this reinforcing body is made by braiding or winding a unidirectional reinforcing fiber roving prepreg 2 onto a coiled lightweight core material 1 made of foamed urethane foam, etc., and then forming the lightweight core material 1 into a ring length. The roving prepreg 2 is cut into two pieces and the two ends are joined together as shown in FIG. 12, and the roving prepreg 2 is impregnated with a resin or the like.

[Summary of the invention]

In this invention, a flexible tube is spirally wound around a cylindrical body, and a feeding tube for feeding the main agent and curing agent of urethane foam from the other end, as well as a movable mixing means attached to the tip thereof, is inserted up to one end of the tube. Then, while feeding the unfoamed urethane foam material mixed with the base agent and curing agent into the tube from the nozzle of this mixing means, the mixing means is gradually moved to fill the entire length of the tube, and then the urethane foam material is To provide a method for manufacturing a coiled lightweight core material, in which a long coiled lightweight core material can be manufactured at a uniform density and at low cost by cutting open a flexible tube removed from a cylindrical body after foaming is completed. It is an object.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Figures 1 to 3 show an apparatus for manufacturing a coiled lightweight core material, in which 8 is a flexible tube with a circular cross section that is spirally wound around the outer periphery of a cylindrical body 4. They are made of plastics such as nylon, or these plastics reinforced with glass fibers or polyester fibers. 5 is flexible tube 3
5a is a fixture for holding the cylindrical body 4 to the fixture 5.
This is a mounting screw. 6 is a tank for storing the main agent of urethane foam, and 7 is a tank for storing the hardening material. Reference numeral 8 denotes a movable mixing means inserted from the upper end to the lower end of the flexible tube 3, and this mixing means includes a main agent feed pipe 9 from the main agent tank 6 and a curing agent feed pipe from the curing agent tank 7. A supply pipe 10 and an air supply pipe 11 for compressed air are connected. 12 is a mixing means 8
These are rollers for moving inside the flexible tube 3.

4 to 6 show the structure of the mobile mixing means 8. 13 is a housing of the mixing means 8, which consists of a main body case 15 and a mixing case 16 that are connected by a partition body 14;
An envelope tube 17 housing the base agent feed tube 9, curing agent feed tube 10, and air feed tube 11 is supported on the holder. 18 is a feeding port 20 provided in the partition body 14 and feeding the base agent 19 into the mixing case 16;
Similarly, the curing agent 21 is fed into the mixing case 16 through a feeding port. Reference numeral 22 denotes a rotating shaft supported by the cutout body 14 via a bearing 23, and a plurality of stirring blades 24 are attached to the rotating shaft 22 that projects into the mixing case 16. 25 is a hollow part hollowed out in the partition body 14, and a drive blade 26 is attached to the rotating shaft 22 located in this hollow part 25. It is rotated by the pressurized air from the pair of air outlets 27, rotates the stirring blade 24, mixes the main agent 19 and hardening agent 21 in the mixing case 16, and produces an unfoamed hard urethane foam material 29 from the nozzle 28. can be ejected. In addition, 25a is a discharge hole of the air in the hollow part 25.

Next, a method for manufacturing the coiled lightweight core material will be explained. First, as shown in FIG. 1, with the movable mixing means 8 inserted up to the lower end of the flexible tube 3, an unfoamed hard urethane foam material 29 is fed into the tube 3 from the nozzle 28. The urethane foam material 29 fed into the tube 3 begins to foam and expand, and the mixing means 8 is pulled up as shown in FIG. 7 in accordance with this expansion speed. This lifting operation is performed by lowering the roller 12. When the mixing means 8 moves until it comes out of the upper end of the tube 3, the entire length of the tube is filled with the urethane foam material 29 as shown in FIGS. 8 and 9. After completing the foaming of the urethane foam material, the fixture 5 is removed from the cylindrical body 4 and the flexible tube 3 is taken out.
By cutting this tube 3 open, a coiled lightweight core material 1 shown in FIG. 10 can be manufactured. As shown in FIG. 11, the lightweight core material produced as described above is wound with unidirectional reinforcing fibers on its surface to obtain a ring reinforcement shown in FIG. 12.

〔Effect of the invention〕

As explained above, according to the present invention, a flexible tube is spirally wound around a cylindrical body, and a feeding tube for feeding the main agent and curing agent of urethane foam from the other end, as well as a mobile mixing device attached to the tip of the flexible tube, is provided. Insert the means to one end of the tube, and while supplying unfoamed urethane foam material mixed with the base agent and curing agent into the tube from the nozzle of the mixing means, gradually move the mixing means to fill the entire length of the tube, Thereafter, after the foaming of the urethane foam material is completed, the flexible tube removed from the cylindrical body is cut open to produce a coiled lightweight core material, thereby producing the following effects.

(a) When an unfoamed hard urethane foam material is fed into a flexible tube 3 with a length of 2 m or more from the lower end and foamed inside the tube while air is released from the upper end, the urethane foam material that has started foaming will move upward. However, when gelation begins, the frictional force with the wall increases due to the small inner diameter of the tube, resulting in uneven density without upward expansion, failure to foam to the top, or air bubbles remaining in the middle. Although there are drawbacks, according to the method of the present invention, a coiled lightweight core material of uniform density can be obtained because the mixing means is moved as the urethane foam material is filled.

(b) Since the flexible tube is spirally wound around the cylindrical body, the coil helix angle and coil inner diameter are highly accurate.

(c) Since the inner wall of the flexible tube is filled with urethane foam material, the foaming pressure generates membrane force in the tube, resulting in a coiled lightweight core material with a uniform circular cross section.

(d) Can be used as core material for FRP coils.

(e) Since the equipment is simple, an inexpensive coiled lightweight core material can be obtained.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an apparatus for carrying out the method of manufacturing a coiled lightweight core material of the present invention, and FIG.
- Line enlarged sectional view of the figure, Figure 3 is also -
4 is a sectional view of the mobile mixing means, FIG. 5 is a sectional view taken along the - line in FIG. 4, and FIG.
The figure is a cross-sectional view taken along the line -- of Fig. 5, Fig. 7 is a diagram of the mixing means in use, Figs. 8 and 9 are sectional views similar to Figs. 2 and 3 filled with urethane foam material, and Fig. 10. 11 is a perspective view of a coiled lightweight core material manufactured by the manufacturing method of the present invention; FIG. 11 is a perspective view of a conventional coiled lightweight core material in which unidirectional reinforcing fibers are wound; FIG. 12 is a perspective view of the same molded ring. 1... Coiled lightweight core material, 3... Flexible tube, 4... Cylindrical body, 5... Fixture, 8...
...Mobile mixing means, 9...Base agent feeding pipe, 1
0...Curing agent supply pipe, 11...Air supply pipe, 12
...roller, 14 ... partition body, 16 ... mixing case, 24 ... stirring blade, 28 ... nozzle,
29...Urethane foam material. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A flexible tube made of plastic such as vinyl chloride or plastic reinforced with glass fiber or the like is spirally wound around the outer periphery of a cylindrical body,
A movable mixing means attached to the tip of a feeding tube is inserted into one end of the flexible tube, and feeds the main agent and curing agent of urethane foam into this flexible tube from the other end, and the above-mentioned While feeding the unfoamed urethane foam material mixed with the base material and the curing agent into the flexible tube, the mixing means is gradually pulled up to fill the entire length of the tube with the urethane foam material, and then the urethane foam material is foamed. A method for manufacturing a coiled lightweight core material, which comprises manufacturing a coiled lightweight core material by cutting open a flexible tube removed from a cylindrical body after completion of the process. 2. The mobile mixing means mixes the main agent and curing agent sent into the mixing case from each feed pipe by rotating a stirring blade using pressurized air from the air feed pipe. 2. A method for manufacturing a coiled lightweight core material according to claim 1, wherein the core material is supplied from a nozzle.