JP3236343B2 - Continuous foaming equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for continuously producing a foamed board obtained from foamable resin particles.

[0002]

2. Description of the Related Art As an apparatus for continuously manufacturing a foamed board using foamable resin particles, a cross-section is substantially rectangular, and along an upper surface and a lower surface inside a tunnel structure surrounded by a plate,
Various devices have been proposed for supplying foamable resin particles between two continuously moving belts and continuously producing a foamed plate via a steam heating device and a cooling device. Above all, the molding apparatus disclosed in JP-A-59-85723 is excellent in practical use and has potential as a production machine.

[0003]

In these conventional devices,
By pressurized steam blown into the tunnel from the steam room,
While the expandable resin particles continuously supplied from the feed zone are heated, the apparatus itself is heated at the same time, and the heat balance is maintained by natural heat radiation.

[0004] Accordingly, the steam supplied as steam is cooled and changes into condensed water, which is contained in the foamed molded article or accumulates on the belt gradually and flows back to the feed zone to change the supply amount of the foamable resin particles. In an extreme case, there is a problem that the supply of the expandable resin particles is hindered and stable production cannot be performed for a long time. With respect to such a conventional technique, the present inventors have earnestly studied an apparatus for continuously and stably producing a foamed board, and have reached the present invention.

[0005] That is, an object of the present invention is to provide an apparatus for continuously producing a foamed board using foamable resin particles, and to stably produce foamable resin particles without being hindered by the supply of foamable resin particles due to condensed water of pressurized steam. It is an object of the present invention to provide a continuous molding apparatus capable of performing the following.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to provide two small holes which are substantially rectangular in cross section and move continuously along the upper and lower surfaces inside a tunnel structure surrounded by plates. In the apparatus for supplying foamable resin particles between the belts having the same and continuously producing a foamed plate through a steam heating device and a cooling device, a drainage channel for condensed water is provided in a plate below a feed zone. Gained by things.

That is, the apparatus is provided with a supply device (2) for the expandable resin particles (1), a steam heating device (3), and a cooling device (4), and has a substantially rectangular cross section and is surrounded by a plate (5). A belt (7) having two small holes continuously moves at the same speed in the same direction in the tunnel structure (6) along the upper and lower surfaces inside the tunnel. The lower plate is provided with a drainage channel (9) for condensed water. The foaming resin particles supplied from the supply device to the belt move continuously in the tunnel together with the belt, and pressurized steam blown from the steam heating device through the small holes of the belt enters between the foaming resin particles. As a result, the expandable resin particles are efficiently heated and expanded, and the expandable resin particles are fused together to form a foamed plate. The pressurized steam blown from the steam heating device becomes condensed water in the vicinity of the feed zone, and the condensed water flows through a small hole of the lower belt into a drainage channel of the condensed water provided on the lower plate of the feed zone. Therefore, there is no accumulation of condensed water on the belt, and there is no hindrance to the supply of the expandable resin particles, so that stable production is possible. The foam plate integrally formed by the steam heating device is cooled by the cooling device while moving together with the belt, and is cooled and solidified to obtain a foam plate.

The expandable resin particles (1) are a thermoplastic synthetic resin, and the type thereof is not particularly limited.
Usually polystyrene-based, polyolefin-based, polyvinylidene chloride-based expandable resin particles having an expansion ratio of 5 to 6
Zero times so-called pre-expanded particles are used. In particular, when high heat insulation performance is required, it is preferable to use foamable resin particles using a vinylidene chloride-based synthetic resin containing hydrochlorofluorocarbon, hydrofluorocarbon, or the like as a foaming agent as a base resin.

The supply device (2) is not particularly limited as long as it is a device capable of uniformly supplying the expandable resin particles onto the belt. The steam heating device (3) heats and integrally forms the expandable resin particles, and is blown into the expandable resin particle group through small holes of the belt using a pressurized steam as a heat source.

The cooling device (4) has a purpose of cooling the temperature of the foam plate integrally formed by heating to a temperature at which secondary expansion does not occur. As a cooling method, a cooling plate is used rather than direct cooling with water. Indirect cooling is preferred. This is because direct cooling with water is not preferable because a drying device is required after cooling. As a refrigerant for cooling the cooling plate, compressed air, cooling water, or the like is used.

The plate (5) forms a tunnel structure and must have a strength to withstand the expansion pressure of the expandable resin particles in the tunnel. Usually, a metal plate such as a thick aluminum plate is used. Preferably, the inside of the plate is coated with a polytetrafluoroethylene plate or coated with polytetrafluoroethylene in order to reduce the frictional resistance with the belt or the foamed plate.

The tunnel structure (6) having a substantially rectangular cross section is one in which the entrance and exit shapes of the tunnel are substantially rectangular, and the sectional dimensions from the entrance to the exit of the tunnel are the same. It is preferable that the dimension in the thickness direction on the tunnel entrance side be larger than the dimension in the thickness direction of the heating zone. Because, by increasing the dimension in the thickness direction at the tunnel entrance side, the expandable resin particles moving in the tunnel are compressed in the thickness direction, and the porosity between the filled expandable resin particles decreases. However, the expansion force at the time of heat molding is applied to improve the fusion property between the expandable resin particles, so that a foam panel with higher performance can be obtained.

Each of the two belts (7) has an endless shape and is moved in the same direction and at the same speed by a take-up roller along the upper and lower surfaces inside the tunnel. As a material of the belt, a steel belt, a rubber belt, a woven fabric, or the like is used, and a steel belt is usually used. The belt is provided with small holes, which serve to blow pressurized steam in the heating zone and discharge condensed water in the feed zone to a drain. The size, number, arrangement, etc. of the small holes can be arbitrarily set, but the hole diameter is 0.3 to 2.0 m.
It is preferable to arrange small holes having a pitch of 5 to 50 mm in a zigzag pattern. If the hole diameter is 0.3 mm or less, the ventilation resistance of the pressurized steam increases, the steam efficiency deteriorates, and the discharge efficiency of the condensed water also deteriorates. When the hole diameter is 2.0 mm or more, it is not preferable because small particles of the expandable resin particles leak from the small holes or protrusions remain on the surface of the foam plate. When the pitch is 5 mm or less, the strength of the belt is reduced. When the pitch is 50 mm or more, the penetration of pressurized steam between the expandable resin particles becomes insufficient, and the efficiency of discharging condensed water is deteriorated. It makes no sense. It is preferable to arrange the small holes in a staggered manner, because the penetration of the pressurized steam between the foamable resin particles becomes more uniform.

The feed zone (8) generally refers to a portion from below the supply device to a position immediately before the steam heating device. However, when a heat retention zone is provided in front of the steam heating device, the feed zone (8) indicates a portion immediately before the heat retention zone and is strictly divided. Not something. The drainage channel (9)
Although provided on the lower plate of the feed zone, a groove or through hole is used. Condensed water flowing out to the drainage channel through the small hole of the belt may be drained to the outside by providing an optional water collecting groove or the like. Also, the position where the drainage channel is provided is generally below the supply device to just before the steam heating device, but if it is too close to the steam heating device, pressurized steam may also be blown out,
It is necessary to provide it at a position corresponding to the steam pressure or the size of the drainage channel. The shape or number of the grooves and through-holes can be arbitrarily set as long as they satisfy the drainage function.

The foamable resin particles supplied on the belt are
It moves continuously in the tunnel while being sandwiched by the upper and lower belts without being hindered by the supply of condensed water, and is heated and expanded and fused by the steam heating device to form an integrally molded foam plate. . Next, the foam board moves together with the belt and is cooled by the cooling device, so that the foam board is solidified, and it is possible to continuously manufacture a stable foam board.

The foamed board thus obtained can be used as it is as a foamed board as it is. However, in order to obtain a foamed board of higher performance, a surface material is applied to the surface of the foamed board after leaving a cooling device. It is also possible to combine them. Since the foam board according to the present invention can be obtained continuously and almost in an endless state, the length of the foam board may be cut to an arbitrary length by a cutting device.

[0017]

EXAMPLES Using the apparatus shown in FIG. 1, a foamed board was manufactured under the following conditions, and the continuous operable time was measured. Table 1 shows the measurement results. <Foam board manufacturing conditions> Base resin of expandable resin particles: Vinylidene chloride-based synthetic resin (product name: Cellmore, manufactured by Asahi Kasei Kogyo Co., Ltd.) Apparent density of expandable resin particles: 40 Kg / m ³ Material of belt: Steel belt Belt width: 300 mm Distance between upper and lower belts: 25 mm Size of small holes: 0.8 mmφ Pitch of small holes: 20 mm Array of small holes: Staggered Heating source: Pressurized steam Heating pressure: 1.0 Kg / Cm ² G Refrigerant of cooling device: cooling water Cooling water temperature: 20 ° C. Line speed: 1.0 m / min Shape and type of drainage channel: U-shaped groove Size and number of drainage channels: 5 mm width × 5 mm depth X
5 equally spaced

[0018]

[Comparative Example] Under the same conditions as in the example, a foam board was manufactured without providing a drainage channel, and the continuous operation time was measured. Table 1 shows the measurement results.

[0019]

[Table 1]

[0020]

The apparatus for continuously forming a foamed plate according to the present invention is
It is possible to provide a foam plate that is stable and can be manufactured economically without being hindered by the supply of the expandable resin particles due to pressurized steam condensed water.

[Brief description of the drawings]

FIG. 1 is a main body side view showing an outline of a molding machine according to the present invention.

FIG. 2 is a cross-sectional view taken along line AA in FIG.

[Explanation of Signs] 1..Expandable resin particles 2..Supply device 3..Steam heating device 4..Cooling device 5..Plate 6 ... Tunnel structure 7 ... Belt 8 ... Feed zone 9 ... Drainage Road 10 ・ ・ Catchment groove 11 ・ ・ Recovery roller

Claims (1)

(57) [Claims] 1. A foaming resin particle is formed between a belt having two small holes continuously moving along upper and lower surfaces inside a tunnel structure surrounded by a plate and having a substantially rectangular cross section. In a device for continuously producing a foamed board by supplying and passing through a steam heating device and a cooling device, a drainage channel for condensed water is provided in a plate below a feed zone, and the continuous forming of the foamed plate is performed. apparatus.