JPH04173109A - Heating device for fiber reinforced composite material - Google Patents

Abstract

PURPOSE:To enable a massive pre-molding material to be heated effectively and uniformly by arranging a plurality of paired electrode plates oppositely cocentrically within a hollow cylindrical body, and making a massive premolding material circulate between the electrode plates, and then heating it in use of high frequency. CONSTITUTION:On the axially central part of a hollow cylindrical body 10, a shaft core 2 comprising of a rotating part 2a and a stationary part 2b is disposed, and on the stationary part 2b, inside electrode plates 4 are fixed cocentrically via support materials 3, and on the rotating part 2a, a plurality of connecting cylinder 7 is arranged via a shaft 6. On the outer peripheral side wall of a main body 10, outside electrode plates 5 are placed in opposite to the inside electrode plate 4, and between the electrode plates 4, 5, annular heating paths are formed through which cylindrical accommodation vessels transfer rotationally. The upper proximity end and lower proximity end of the accommodation vessels 8 are held by means of connecting rings 7, and the accommodation vessels 8 rotate about the rotating shaft 2a and are constructed enabling rotation. Substances 1 to be treated are supplied into the accommodation vessels 8 and heated through rotation of afore-mentioned annular heating paths.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an apparatus for efficiently heating a fiber-reinforced composite material formed into a block by high-frequency heating.

[Prior Art] As a method for molding fiber-reinforced composite materials, there is a method in which the material is first preformed and then molded into a desired final shape. The material to be preformed in this way (hereinafter referred to as preformed material) is known to be in the form of a sheet or a block, and is heated by a heating device using an infrared heating furnace, an electric heater, etc. in preparation for final molding. It is something.

In the above-mentioned preforming material, when trying to obtain a uniform heating state with a small temperature gradient, a sheet-like preforming material is more advantageous than a bulk preforming material. However, sheet-like products are expensive to manufacture, and
There is a complication in that it often requires lamination to create the final form.

Therefore, the inventors of the present invention have conducted extensive research on heating methods for bulk preforming materials, and have found that by blending a telephone loss improver into the bulk preforming materials and heating them with high frequency using an electrode plate, the bulk He developed a method for heating preforming materials and filed an application (Patent Application No. 1-32283).
9).

[Problems to be Solved by the Invention] An object of the present invention is to provide a heating device that can efficiently and uniformly heat a block of preformed material by employing the heating method described above.

[Means for Solving the Problems] The present invention that achieves the above object includes a plurality of electrode plates connected to a high frequency transmitter and arranged in pairs concentrically and facing each other in a hollow cylinder. The gist is to form an annular heating passage between the plates, provide a rotation mechanism for rotating the bulk preformed material along the heating passage, and perform high-frequency heating while the bulk preformed material circulates. .

[Operations and Examples The present invention will be explained below based on the drawings.

FIG. 1 is a schematic side sectional view, and FIG. 2 is a schematic side sectional view, and FIG.
FIG. In addition, some parts of Figure 2 include B- in Figure 1.
A cross section B and a cross section C-C are included.

A shaft core 2 consisting of a rotating part 2a and a fixed part 2b is disposed at the shaft center of the hollow cylindrical main body 10, and an inner electrode plate 4 is concentrically connected to the fixed part 2b via a support member 3. It is fixedly installed. On the other hand, a plurality of connecting rings 7 are disposed on the rotating portion 2a via a shaft 6. In addition, the above main body 10
An outer electrode plate 5 is disposed on the outer circumferential side wall of the inner electrode plate 4 in parallel with the inner electrode plate 4, and an annular heating passage in which a cylindrical storage container rotates is formed between these electrode plates 4.5. has been done.

The storage container 8 is made of a material with low high frequency absorption such as quartz)
The vicinity of the upper end and the vicinity of the lower end of the storage container 8 are held by the connection ring 7, and are fixed to the rotating shaft 2a via the shaft 6. A gear 9 is fitted on the upper outer periphery of the storage container 8, and a rotating roller 1 is fitted on the lower end.
1 is disposed and rotates around a rotating shaft 2a, and the storage container 8 itself is configured to rotate.

Note that the heating device according to the present invention has a population section 20 and an outlet section 30.
Although not limited by the structure, a typical example is shown in FIG.

The objects 1 to be treated are intermittently cut out one by one by the magazine 21, transported to the artificial center 22 by the pressing plunger 24, and then supplied into the storage container 8 of the heating device by the carry-in piston 25. The storage container 8 includes the electrode plate 4,
The object 1 to be processed is heated by rotating and circulating through the annular heating passage between the 5 parts.

After heating, the workpiece 1 located at the lowest stage of the storage container 8 is lowered out of the storage container 8 by the elevator device 31, further pushed out to the discharge position by the pusher 32, and transferred to the next process by the shooter 33. Sent.

That is, the storage container 8, which is stopped at a position corresponding to the population part 20 and the outlet part 30 of the object to be processed, is located at the upper entrance part 2.
At the same time as the unheated workpiece 1 is supplied from the outlet 30, the heated workpiece 1 is discharged from the lower outlet part 30. When the supply and discharge of the workpiece is finished, the next storage The container 8 rotates one pitch about the axis so that it comes to the supply/discharge position, and the supply/discharge of the object 1 is repeated.

Therefore, for example, in a storage container that can accommodate five objects to be processed, the objects to be processed will be heated for five rotations around the axis 2, and then discharged from the apparatus.

Note that if the dielectric loss coefficient of the object to be treated is low and dielectric heating cannot be performed using only the object to be treated, a dielectric loss improver which is a substance having a high dielectric loss angle or a high dielectric constant may be added. Examples of the dielectric loss improver include silicon carbide, carbon black, various rubber materials, marble, soda glass, ethylene glycol, and glycerin. The blending amount of the dielectric loss improver is not particularly limited, and the optimum blending amount may be determined by taking into account its own dielectric loss factor, but as a guide, it should be 0.1 to 0.1 to the total weight of the bulk preforming material. It is desired that the content be 40% by weight, which makes it possible to increase the dielectric loss of the bulk preformed material to the extent that the high frequency heating effect is sufficiently dispersed. However, if it is added in excess, the strength of the bulk preformed material will decrease, so the more preferable addition amount is 0.1 to 4.5% by weight.

Other raw materials used in the present invention can be selected from a wide variety of general-purpose materials that do not go against the purpose of FRP production. For example, the plastic material may be thermoplastic or thermosetting, and the reinforcing fibers may be known reinforcing fibers such as glass fibers or carbon fibers. Other additives include binders, curing agents, plasticizers, fillers, antioxidants, pigments, and the like, as required, and all conventionally known additives can be used in combination.

Although the present invention does not limit the frequency used for heating, a high frequency on the order of MHz is usually used, and 16 to 100 MHz is particularly preferred.

[Effects of the Invention] Since the present invention is configured as described above, it is possible to uniformly heat a preformed lump made of a plastic material and reinforcing fibers in a short time.

Further, the above-mentioned apparatus can continuously supply and discharge the material to be treated and heat it, is compactly constructed, and does not damage the fibers contained in the preformed material. Furthermore, since high frequency is used, it has an excellent effect in that even thick objects can be heated uniformly.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of a heating device according to the present invention as viewed from the front, FIG. 2 is a schematic sectional view as viewed from above, and FIG. 3 is a schematic explanatory diagram showing the structure of an inlet and an outlet. 1... Workpiece 2... Axis core 4... Inner electrode plate 5... Outer electrode plate 8... Storage container 10... Main body

Claims (1)

[Claims] This device heats a bulk preformed material of a composite material made of a plastic material mixed with reinforcing fibers, in which a plurality of paired electrode plates connected to a high frequency transmitter are arranged in a concentric circle in a hollow cylinder. and forming an annular heating path between the electrode plates, and providing a rotation mechanism for rotating the bulk preformed material along the heating path, and high-frequency heating the bulk preformed material while it circulates. A heating device for fiber-reinforced composite materials.