JPS6025372B2 - Method and apparatus for drying chopped strands of glass fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method and apparatus for drying wet chopped strands of glass fibers, and more particularly to a method and apparatus for drying wet chopped strands with hot air under a fluidized bed.

Recently, glass fiber-reinforced thermoplastic resin products have become widely used as materials for various high-strength parts.

These glass fiber reinforced thermoplastic resin products are generally produced by pelletizing a mixture of thermoplastic resin pellets and chopped glass fiber strands using an extruder, and molding the resulting pellets containing glass fibers using an injection molding machine or the like. Manufactured by. Chopped strands of glass fiber, which are the reinforcing material for such glass fiber-reinforced thermoplastic resin products, are produced by cutting glass fibers from a bushing, winding them up as strands, or rovings formed by aligning the strands under wet conditions. Alternatively, the spun wet glass fibers can be fed directly to the cutter as a strand without winding, cut to the desired length, and then dried. Manufactured by.

Conventionally, wet chopped strands that have been cut with a cutter are dried by depositing the wet chopped strands on a conveyor and then passing them through a tunnel-type hot air dryer for continuous drying. This is carried out using a direct heating method using hot air, in which the bridge is collected and deposited in a suitable container, and then left to stand in a hot air drying chamber to dry in batches.

The main reasons for drying chopped strands under static eye are to prevent mixing of chopped strands with resin pellets, processability and moldability in compounding, and to prevent chopped strands from being a factor that inhibits the product properties of the final molded product, such as strength properties. The purpose is to suppress yarn cracking, splitting, or fuzzing of the strands as much as possible. In this direct heating drying method of chopped strands using hot air, the chopped strands are dried by passing high-temperature hot air along the stacked surface of the chopped strands to evaporate water from the surface layer, and after the water evaporates, the high-temperature surface glass This is achieved by applying conductive heat to the next layer, heating it to evaporate its moisture, passing the generated vapor through the layer and dissipating it out of the deposited layer, and this process is continuously repeated to the lower layers in sequence. be done.

Therefore, the determining factor for the drying time in this drying method is not the drying temperature, but the properties of the deposited chopped strands, the main properties being moisture content, high specific gravity and layer thickness, such as rewetting and cutting a normal dried strand cake. It takes about 2 feeding hours/130 qo to dry wet-cut chopped strands with a moisture content of 20 to 25%, a high specific gravity of 0.5 to 0.6 m/s, and a lamination thickness of 8 qo. For drying direct-cut chopped strands with a moisture content of 10-15% and a high specific gravity of 0.5-0.6 strands and a lamination thickness of 70, obtained by supplying the strand directly to the cutter without winding it up and cutting it. It requires a very long time of about 1 feeding hour/130℃, and also requires a long time of at least about 5 to 6 hours for cooling the dried chopped strand product prior to packaging. This has become a major bottleneck in streamlining processes, such as making them continuous. Furthermore, such long drying times cause problems such as the binder applied to the fibers during the drying process migrating to the surface layer of the deposited chopped strands, reducing the quality and yield of the product.
There is a problem in that such a long heat history may lead to binder destruction, which deteriorates the physical properties of the molded product. In addition to the above-mentioned drying method using hot air, methods for drying chopped strands using high-frequency heating or microwave heating are known. When these heating drying methods are used, the drying time can be significantly shortened to about 15 to 30 minutes, and drying is highly uniform and excellent drying efficiency can be achieved, but when using these electromagnetic wave heating methods, chopped strands The difficult problem is that the deposited layer of chopped strands must be formed substantially completely on a horizontal surface because the power absorbed by the layer is proportional to the area of the chopped strand layer and inversely proportional to its thickness; Particularly in the case of high-frequency heating, the electromagnetic waves are not absorbed after the moisture evaporates, so the temperature cannot be raised to 10,000 or higher, and there is a problem that curing of the binder becomes insufficient. The latter problem can be solved by employing microwave heating, but it requires strict microwave control, and even the slightest miscontrol can lead to binder destruction due to overheating, resulting in discoloration of the chopped strands and damage to the chopped strands. There are problems resulting in poor integrity and/or poor adhesion between the glass fibers and the resin. Furthermore, it is said that the use of these high frequency waves or microwaves is not only expensive in terms of equipment, but also in terms of running cost, which is three to four times higher than hot air heating. For these reasons, drying methods using high frequency heating or microwave heating have not yet been used as a general method. Thus, the primary object of the present invention is to provide a dynamic drying method and apparatus that can dry chopped strands in a very short time using hot air, and that can also perform forced cooling using cold air.

A second object of the present invention is to enable continuous, short-term drying and cooling of the chopped strands themselves under continuous transport, thus making it possible to continuousize the process from spinning glass fibers to packaging chopped strand products. An object of the present invention is to provide a method and apparatus for dynamic drying of chopped strands.

According to the hot air heating drying method and its apparatus of the present invention, the wet chopped strands formed by cutting the glass fiber strand or strand product under humidity far exceed the concept of the conventional static hot air heating drying method. , it is possible to dry the chopped strands in an extremely short time of several tens of minutes, comparable to high frequency heating or microwave heating, for example, and to apply cold air to the dried chopped strands using the same drying principle as that of the present invention. Forced cooling can be performed in a very short time, that is, in a short time of about 5 to 10 minutes. Furthermore, according to the present invention, the problems of binder migration and binder destruction during drying are virtually completely eliminated, and even though static drying is used, the characteristics of chopped strand products are not affected by static drying. It is possible to obtain products with properties comparable to or better than those obtained by Furthermore, according to the invention, the drying and cooling of the chopped strands can be carried out as a continuous process under its own transport, and because of this and because the drying and cooling can be carried out in a very short time, the chopped strand product can be spun into glass fibers. It can be manufactured in a continuous, integrated process. The method of the present invention, which has achieved the above objects and effects, basically consists of cutting a glass fiber strand or strand product under a wet condition, and then layering a wet chopped strand to form a continuous layer. The method is characterized in that the chopped strands are dried under a fluidized bed by blowing out and conducting a large number of fine heated air streams from below the wet chopped strand layer that is continuously transferred.

In a preferred embodiment of the present invention, a large number of thin cooling air streams are ejected from below the dried, high-temperature chopped strand layer that is continuously transferred following the heated air ejection and conduction step. The method includes a method in which dried chopped strands are forcedly cooled under a fluidized bed. In a further preferred embodiment of the present invention, the heating air flow is applied to the wet chopped strand layer under continuous transport, and the cooling air flow is subsequently applied to the dry chopped strand layer under continuous transport to perform the drying and cooling steps. This includes a method for continuously collecting chopped strand products that can be packaged as they are.

On the other hand, the device of the present invention basically consists of wet chopped glass fiber strands that are deposited and transferred in layers, and has a large number of small holes for blowing out and conducting heated air to dry the chopped strands. A perforated plate is integrally arranged transversely inside the device; the upper part of the perforated plate controls the exhaust amount of the heated air blown out through the small holes, and the lower part controls the heated air to be exhausted through the holes. each comprising at least one venting chamber, the venting chamber having a closure in its box wall for supplying wet chopped strands to one end region of the perforated plate, and an opposite side of the closure and An opening □ for taking out the dried chopped strands formed at a level that allows the chopped strands on the perforated plate to be discharged, and an opening □ for exhausting the heated air ejected from the ventilation chamber to the exhaust chamber through the small holes of the perforated plate. each vent chamber has at least one vent in its surrounding wall for receiving heated air from the heated air; each of the vents and vents has an exhaust system; , a blower system including an air heating device is connected; and at a position above the perforated plate, the chopped strands penetrate into the group and run or rotate at a plurality of fixed positions to generate the chopped strand group. The invention is characterized in that a transfer device having a large number of rod-shaped bodies is disposed to transfer the images while forming them in layers.

In a particularly preferred embodiment of the present invention, in addition to the at least one ventilation chamber, the lower part of the perforated plate also allows the cooling air to be exhausted through the small holes of the perforated plate adjacent to the cut-out closing side of the chopped strands. The ventilation chamber for cooling air has an opening □ in its surrounding wall for receiving cooling air from a cooling air source, and the opening □ has an opening □ for receiving cooling air from a cooling air source. It includes a device that performs drying and cooling as a continuous process to which a blower system for commercial air is connected.

The invention will now be described with reference to preferred embodiments of the accompanying drawings.

0 Figure 1 shows the continuous process from glass fiber spinning to strand cutting, drying of the chopped strands, and product packaging, and Figure 2 shows the
The structure of the dryer shown in Fig. 3 is shown in a side sectional view, Fig. 3 shows a sectional view taken along line m-m of Fig. 2 including the ventilation system, and Fig. 4 shows the transfer device. Another example is shown.

In the figure, 10 indicates a paper thread device, and a hooking 11a
, 11b, 11c, filament 12a,
12b, 12c are binder coating devices 13a, 13b
, 13c and directly enters the cutter 20 after being concentrated into one strand 15a, 15b, 15c by concentration shoes 14a, 14b, 14c, respectively. A guide roller 21 having a groove corresponding to the number of cutter strands, and a freely rotating feed loaf 22 whose surface is made of an elastic material having a large coefficient of friction against glass fibers such as rubber or synthetic resin.
It consists of a cutter roller 23 which is in pressure contact with a feed roller 22 and is actively driven by a motor, and has a large number of blades protruding radially from the surface thereof.

Cutters 2 wet strands 15a, 15b,
15c is wound around the feed roller 22 through each groove of the guide roller 21, and cut to a length determined by the blade interval by the blade biting into the feed roller surface at the pressure contact point between the feed roller 22 and the cutter roller 23, A chopped strand 30 is formed.
The chopped strands 30 typically have a moisture content of about 10 to 15 by weight, although this can vary depending on the amount of binder applied during spinning. In the glass fiber spinning and direct cutting process, the strand 158 is tightly wound around the surface of the feed roller 22 in a wet state.
, 15b, 15c to the feed roller 22 constitutes a fiber forming force, and the glass filaments 12a, 1
2b, 12c are pulled out from the bushings 11a, 11b, 11c and made into fibers. chopped strand 30
As mentioned above, it can be produced by direct connection with spinning using the direct cutting method, and it is preferable to make it a continuous process in this way, but methods other than this direct cutting method, such as paper yarn and concentrated strands A strand of dry cake formed by winding it onto a winding tube is directly coated or wetted with an aqueous treatment agent that may or may not contain a sizing agent, etc., and then fed to a cutter and cut. Alternatively, it can also be produced by winding up a strand of a so-called dry cake onto a winding tube and drying it, after a second wet coating or simply a wet treatment, feeding it to a cutter and cutting it.

Although the above explanation has been limited to strands, the present invention is also applicable to processed products of strands, such as rovings, which also include so-called straight-wound rovings that are directly formed into rovings during spinning by omitting the roving process. It is obvious that it can be applied. In this specification, such processed products are referred to as strand products. The moisture content of the chopped strands thus formed varies depending on the type of strand or product thereof, but is generally within a range of about 20 to 25% by weight. Chopped strand 30 cut and formed with cutter 20
is a suitable conveying means, such as a compare system 40a, 4.
0b, 40c, are conveyed while being dropped and deposited on them, are supplied to the drying device 50 according to the present invention, are dried and preferably continuously cooled by the method of the present invention, and are taken out as chopped strand products and then packed. Device 9
Packed with 0.

The inside of the drying device 50' has a perforated plate 51 fixedly disposed transversely. A chopped strand transfer device is arranged above the perforated plate 51.

Drying device 5 Kawa Masa, the exhaust chamber 52 and the ventilation chamber 53a
, 53b. In the drying device 50', the perforated plate 51 is disposed horizontally in the device or slightly inclined toward the product outlet direction, and has a perforated plate 51 on almost its entire surface.
The through-holes 54 have diameters of 1 to 5 ribs, preferably 2 to 3 ribs, and are approximately uniformly distributed with a porosity of about 1.5 to 10%, preferably 2 to 3%.

The exhaust chamber 52 has in its surrounding wall a closure 55 for supplying the wet chopped strands to one end region of the perforated plate 51 and, on the opposite side of the closure 55, for receiving the chopped strands transferred over the perforated plate 51. It has a chopped strand take-out opening □56 formed at a level to be discharged and a hot air exhaust port 57, and an exhaust system is connected to the exhaust port 57 from the outside.

The ventilation chamber is separated by a partition plate 58 as shown in the figure, between a ventilation chamber 53a for heated air adjacent to the rear end wall, that is, the end wall on the side of the chopped strand supply opening 55, and a front end wall, that is, the end wall on the side of the chopped strand outlet 56. It is particularly preferable to have a structure divided into a ventilation chamber 53b for cooling air adjacent to the strand, but the high temperature chopped strands dried on the perforated plate 51 by a jet of heated air are left to cool as in the conventional method. Of course, this is also possible, and in such a case, there is no need to provide the ventilation chamber 53b for cooling air.

Although each of these ventilation chambers 53a and 53b can be divided into a plurality of chambers, usually one chamber each is sufficient to perform its function.

Further, although the ventilation chambers 53a and 53b are separated by a partition plate 58 in the illustrated embodiment, they may be formed separately without using the partition plate. Each ventilation chamber 53a,
53b has ventilation openings 59a and 59b in its side wall or bottom wall, and the former is connected to a blower system for heating air, and the latter is connected from the outside to a blower system for cooling air. .

These openings ○59a and 59b are formed in plural numbers depending on the size of the ventilation chamber, or in correspondence with each ventilation chamber when each ventilation chamber is divided into a plurality of chambers, and can be provided independently for each of them, or can be connected to the main ventilation device. It is also possible to connect a blower system branched from the system. The sending/receiving E wind device system consists of a blowing/discharging device system for heating air and a blowing device system for cooling air.
The former chick blowing system is connected to the blowing fan 60 and the opening 59a of the ventilation chamber 53a.

An air blower system consisting of a duct having a damper (not shown) for adjusting air flow rate and a heating device 60 disposed in the middle of the duct 61 for heating air sent from a fan 60 to a desired temperature; , extends from the exhaust fan 63 and the exhaust port 57 of the exhaust chamber 52 and is connected to the fan 63.
It consists of an air exhaust system consisting of a duct having a damper (not shown) for adjusting the volume of sea air, and an exhaust duct 65 extending from a fan 63. These blower system and Hifu device system are connected to each other via a circulation duct 66, and heated air sent from the blower system and blown into the exhaust chamber 52 is sucked by an 8E fan 63. Circulation duct 66
Preferably, the air is circulated through the air blower system. This shielding system connects the exhaust duct 65 to a dust collector 67 such as a cyclone, and connects the exhaust duct 65 to a dust collector 67 such as a cyclone.
This can be completed by extending a circulation duct 66 from the air blower system and connecting it to the intake side of the blower fan 60 of the blower system. In a particularly preferred embodiment including a ventilation chamber 53b for cooling air, the ventilation system for cooling air connected to the ventilation chamber 53b is connected to the ventilation fan 68 and exits from the fan 68 to the opening 59b of the ventilation chamber 53b. It consists of a duct 69 connected to it and having a damper (not shown) for adjusting the amount of air blown.

It is not particularly necessary to form the drum wind device system independently, and as shown in the figure, the exhaust chamber is formed into the exhaust chamber 5 for the heated air.
It is sufficient to have the same configuration as in the second embodiment and to have the air dribbling system function simultaneously for exhausting heating air and cooling air. The chopped strand transfer device is a device that has a large number of rod-shaped bodies that penetrate into the chopped strand group and move or rotate at multiple fixed positions to form the chopped strand group in layers and transfer the chopped strand group. Consists of.

One example of the transfer device described above is shown in FIGS. 2 and 3 with five drying devices incorporated therein.

This transfer device consists of two rollers 70a, 70b, an endless belt 71 stretched around both rollers, and a number of belts 72 attached to the surface of the belt 71 so as to extend outward. The rollers 70a and 70b are located above the perforated plate 51 inside the exhaust chamber 52, and control the position of the end region of the perforated plate 51 where the chopped strands supplied from the chopped strand supply gate 55 are first deposited and the removal of the chopped strands. A perforated plate 5 is provided at a position close to the closing opening 56.
1 and arranged transversely in a substantially orthogonal relationship with it,
A shaft 73 extends through both side walls of the exhaust chamber 52 and is rotatably supported by conventional means, and at least one roller is positively driven via the shaft by an external motor, not shown.

Inorganic belt 7 stretched around rollers 70a and 70b
1 has a width comparable to that of the perforated plate 51, and as the roller rotates, the supply opening 55 side end area of the perforated plate 51 and the take-out opening 5
The perforated plate 51 is configured to circulate between the perforated plate 51 and the perforated plate 51.

This endless belt 71 must be such that heated air and cooling air ejected from the ventilation chambers 53a and 53b through the small holes 54 of the perforated plate 51 and into the exhaust chamber 52 can pass therethrough substantially without any obstruction, for example. A chain belt is preferred. A large number of rods 72 extending outward are attached to the surface of the endless belt 71, and when the belt 71 rotates, they are supplied to the end region and sequentially penetrate into the stacked chopped strands to form them into a layer. As the belt 71 rotates, it travels through the chopped strand layer 74 that has been formed.

These camphors 72 can be made of iron, for example. Birch 72 is normally installed perpendicular to the belt surface, but
It can also be installed at a slight angle. Their spacing is generally about 10 to 20 skins. Another example of a transfer device is shown schematically in FIG.

This transfer device is connected to the end area of the perforated plate 51 and the removal opening □5.
A plurality of rollers 70'a, 70' with pins are rotatably supported in positions similar to those of the rollers 70a, -70b, at positions close to 6, and at appropriate intervals between the two positions.
b, 70'c..., each of which is actively driven independently or together. A number of outwardly extending pins 72' are attached to the surface of each roller, and as the roller rotates, the pins 72' successively penetrate into the chopped strands, rotate, form them into layers, and transport them. When the chopped strands are layered, laid, and transferred using these rod-shaped bodies, sometimes the chopped strands are transferred in a lump, but this is because the perforated plate 51 is set long in advance, The problem can be solved by increasing the length of the transfer zone due to the ejection of a heated air stream. Further, even in this case, when the chopped strands are not separated into individual chopped strands and are discharged from the take-out port 56 as a lump, they can be removed by a sorting device 8, which will be described later. The three wet chopped strands conveyed by the compare systems 40a, 40b, 40c and fed from the feed entrance 55 of the drying device 50 are deposited on the end region of the perforated plate 51.

To explain with reference to the transfer device shown in FIGS. 2 and 3, the camphor 72 of the belt 71 enters into the accumulated chopped strand group, and as the belt 71 rotates, the removal opening 56
When traveling in the direction of , the accumulated chopped strands are birch 7
2, and is continuously transported while forming a layer 74 on the perforated plate 51. At this time, the running speed of the camphor tree 72 is generally about 0.1 to 1 skin/min, preferably about 0.2 to 0.4 skin/min. On the other hand, the air blown from the blower fan 60 for heated air is heated to a desired temperature by the heating device 62, enters the ventilation chamber 53a for heated air through the duct 61, and heats the perforated plate 51. The layer 74 of chopped strands being transferred through the perforated plate is electrically connected to the exhaust chamber 52 through the large number of small holes 54 and ejected.

In this step, the chopped strands of the layer 74 are in a relatively close contact with each other due to their high moisture content and high adhesiveness at the initial stage of transfer, but the moisture evaporates in a short time due to the jetting and conduction of heated air. The chopped strands are divided into individual particles and floated up from the perforated plate 51, and mixed while forming a fluidized bed, and at the same time, drying progresses as much as possible. For heated air to function in this way, it must have the desired temperature and output. These conditions depend on the amount and properties of the chopped strands, as well as the conditions of the perforated plate and the transport conditions.In particular, the amount of hot air emitted must be such that the chopped strands forming the fluidized bed are not actually scattered. Therefore, it is not possible to comprehensively specify these conditions, but approximately 120-180q
o, preferably in the range of about 140 to 160 o'clock/sec, and for each pore about 3 to 15 o/sec, preferably about 6 to
A volume that achieves a jetting rate of low/second is suitable. In particular, the heated air conducted through the chopped strand layer 74 has a temperature of about 1,000 in the feces directly above the layer 74.
It is preferable to choose the temperature and the jetting speed of the heated air supplied so that it has a temperature above 0, preferably above about 11,000, which temperature is of course lower than the temperature before conduction.
Under such conditions, ordinary types of wet cut chopped strands and direct cut chopped strands having a moisture content of about 10 to 25% are completely dried in about 15 to 3 minutes. In the case of such short drying times, there is a risk that the curing of the binder may be somewhat insufficient, especially when certain hardening binders are used as binders, which may be caused by, for example, supplied heated air and conduction heating. This can be solved by setting the temperature higher than that of the air and/or using a drying device with a longer perforated plate. When using such a transfer method and drying conditions, it is preferable to dry relatively long chopped strands, for example, six ribs. However, shorter, chopped strands can be dried well by controlling the conditions slightly. The chopped strands dried as described above usually have a temperature of about 10,000°C or higher.

Take out this high temperature chopped strand as it is and close the opening 5.
Although it is possible to take out the drying material from the drying method and release it in the same manner as in the conventional method, in order to take advantage of the high efficiency of drying according to the present invention, it is preferable to operate the cooling air system and perform forced cooling using the same principle as the drying method described above. It is. That is, the ventilation chamber 53b is passed through the duct 69 from the ventilation fan 68 for cooling air.
Cooling air Z is blown through the small holes 54 of the perforated plate 51 to blow it out. The cooling air ejected from the small holes 54 passes through the high-temperature dry chopped strand layer 74, which is transferred above the porous slope under the fluidized bed, and exits the chopped strands into the exhaust chamber 52 while being cooled. In this step, it is sufficient for the cooling air to have an external temperature of room temperature. Further, the jetting speed of the cooling air from the small holes 54 of the perforated plate 51 may generally be 4 times lower than the jetting speed of the heated air, usually about 1 to 10 times per second, preferably 4 to 6 times per second. /second.
By this dynamic cooling under the fluidized bed, the chopped strands having a temperature of about 10,000 or higher are cooled to room temperature in about 5 to 10 minutes. In the above drying-cooling process, although this method is dynamic drying and cooling with heating air and cooling air, as explained in connection with the removed fluff in the description of the secondary air exhaust system, The chopped strands retain their integrity substantially completely even under the blast of heated air and cooling air, and have properties comparable to those obtained by static drying, as will be demonstrated in the examples below. In some cases, it gives even better chopped strands, and also improves the
Since heating is performed for a short time while mixing, problems of binder migration and its destruction practically do not occur. The heated air and cooling air that blows out from the ventilation chambers 53a, 53b through the small holes 54 of the perforated plate 51, conducts through the chopped strand layer on the perforated plate, and exits to the exhaust chamber 52 is sent to the exhaust fan 63.
The air is sucked and exhausted together through ducts 64 and 65, and preferably the air enters a dust collector 67 to remove fluff, etc., and then passes through a circulation duct 66 to a blower fan 6. The air is further heated by a heating device 62 and recycled as heated air. The amount of storm radiation removed in this exhaust process does not depend on the effective ejection speed of heating air and cooling air, and is approximately constant, approximately 1.0 to 2.5% of the amount of chopped strands supplied. be.

This is because the chopped strands are virtually free from fiber splitting and filament breakage due to the injection and conduction of heated air and cooling air to the chopped strand layer, and the collected and removed dust particles are generated when the strands are cut with a cutter. This also means that according to the present invention, fine divided fibers and strands generated when cutting the strands are simultaneously removed during the drying and cooling process, resulting in a good chopped strand product. In the case of conventional Seireki drying, a considerable portion of the fine separated fibers and strands described above are dried while remaining attached to the chopped strands, which is thought to be one of the reasons why chopped strand products are bulky. . The dried and cooled chopped strands were dropped from the product take-out opening 56 into the sorting device 8, and the miscut chopped strands and other defective chopped strands were sorted as shoulder goods and disposed of through the discharge port 81 into the removal container 82. After that, it passes through a metal removal device 83 and enters a product storage container 84 under weighing, and when a predetermined amount is reached, it is transferred to a packaging device 90', and the packaged product 9
It is packed in 1.

In the above sorting process, the chopped strands dried according to the present invention have attached wind lines removed by a jet of air flow, and since it is extremely rare to have them attached, binder migration actually occurs. Since the formation of agglomerates of chopped strands due to migration can be avoided, smooth continuous discharge from the sorting device 80 in substantially fixed amounts is possible.

Next, the present invention will be further explained by examples. However, it goes without saying that the present invention is not limited to these Examples. Example 0 Glass fibers with a diameter of 13 mm were spun from three bushings with 80 hard tip nozzles under the application of a conventional binder, and one strand of each was collected by a collecting shoe and immediately after feeding. The loaf was introduced through a guide roller into a cutter consisting of a cutter roller having a plurality of blades projecting radially at equal intervals from the circumference of the loaf and pressed against the loaf, and cutting the loaf through a guide roller.

The formed chopped strands with a moisture content of about 12% are accumulated on a conveyor placed directly below the cutter, and then conveyed and supplied to a drying device of the type shown in Figures 2 and 3, where they are dried and cooled to become a product. I took it out. The moisture content of these products was below the constant moisture content, that is, below 0.03%, and they were substantially completely dried. In the drying process, the supply rate of the chopped strands was about 45 k9/hour, and the layer thickness of the chopped strands on the porous plate was approximately 40 to 50 mm under the hot air jetting conditions described below. In the drying equipment, the perforated plate has a size of 40 mm width x 2700 mm sail length, and the supply side force of 0.8 (40 mm width x 200 mm width) of the chopped strand is due to the heated air under the perforated plate. the drying area corresponding to the ventilation chamber for cooling air, and the remaining cooling area corresponding to the ventilation chamber for cooling air.

This perforated plate has small holes with a diameter of 2 willows distributed uniformly with a pore ratio of 3%. On the other hand, the transfer device placed above the perforated plate consists of a chain belt that is stretched between two loaves and has a large number of vertical transfer rods on the surface at a pitch of 150 mm. The rate was set at 350 pieces/minute. This drying apparatus has a blower system for heating air and a blower system for cooling air connected to each of its ventilation chambers, and a blower system having a cyclone connected to its exhaust chamber. Room temperature air was used as the cooling air, and the jetting speed from the small holes of the perforated plate was set at 5 m/sec. According to this specification, the drying time is about 3 minutes, and the cooling time is about 10 minutes. The drying conditions and properties of the resulting product chopped strands were determined by drying the same wet chopped strands with a thickness of 6 ribs and a high specific gravity of 0.55 to 0.56 mm/fin.
Table 1 shows the characteristics when dried statically for 10 hours under hot air circulation of 3,000 mph (0.5 air/sec).

The latter is shown in the table as ``Seireki.'' In Table 1, T
cl is the temperature of the heated air before passing through the small holes of the perforated plate,
Further, Tc2 is the temperature of the air immediately above the chopped strand layer when the heated air passes through the small hole, conducts through the chopped strand layer, and is ejected into the exhaust chamber.

The adhesion rate is the percentage of the binder to the fiber weight in the dried product, and the insolubilization rate is the weight percentage of the amount of insoluble binder to the amount before treatment when the dried chopped strands with the binder are boiled and eluted in toluene for 1 hour. be.

A chopped strand with a flow value of 100 mm was put into a square bell hopper with a side length of 2 mm at the inlet and a height of 15 mm. It means the discharge time when opening the exit at the 2.5 corner below and discharging all the chopped strands, seconds/100
It is represented by evening.

The smaller this value is, the less fluff there is, meaning that it is a high-density product. For high specific gravity, evenly put 200 yen chopped strands into a 1000 yen graduated cylinder.
The volume was read and expressed in evening/earth.

Experience has shown that the higher the specific gravity, the less fluff and the higher the density of the product. In terms of fluff incidence, CS is 1
Put the chopped strands of 00 strands into a 1000' beaker, seal, vibrate 3000 times, vibrate at the defibration rate of the chopped strands when mixed, and after mixing, pass through a 16-mesh ring to remove the unwoven fabric remaining on the striations. It is the ratio (%) of fiber amount to the original chopped strand amount, and CS
/R is a chopped strand of 40 strands and a diameter of 3 of 60 strands.
．． This is the fibrillation rate of chopped strands when treated together with a gutter fat pellet with 5 ribs and 3 ribs in length as described above.

These values provide a measure of the resistance of the chopped strands to external mechanical forces, and the smaller the value, the better the aggregateness and integrity of the chopped strands. Table 1
Drying conditions and chopped strand characteristics comparison system, 50... Drying device, 51... Perforated plate, 52.
...Exhaust chamber, 53a, 530...Ventilation chamber, 54...
Small hole, 55... Supply gate, 56... Takeout closing port, 57
...exhaust port, 59a, 59b...ventilation gate, 60.
...Blower fan for heated air, 62...Heating device, 63
...Exhaust fan, 67...Dust collection and removal device, 68...
Blower fan for cooling air, 70a, 70b...roller, 71...endless belt, 72...camphor, 70'a,
70'b, 70'c...roller with pin, 72'...pin,
74... Chopped strand layer, 80... Sorting device, 83... Metal removal device, 84... Product storage container, 9
0... Packing device, 91... Packing product.

[Brief explanation of the drawing]

Figure 1 is a diagram schematically showing the continuous process from glass fiber spinning to strand cutting, drying of the formed chopped strands, and product packaging, and Figure 2 is the structure of the drying equipment used in the process of Figure 1. FIG. 3 is a side sectional view showing the ventilation system, and FIG.
and FIG. 4 shows another embodiment of the chopped strand transfer device. 10... Spinning device, 12a, 12b, 12c. ...Glass filament, 15a, 15b, 15c...Glass fiber strand, 20...Cutter, 30...Chopped strand, 40a, 40b, 40c...Figure 4 Ship Figure 2 Figure 3

Claims (1)

[Scope of Claims] 1. Wet chopped strands obtained by cutting a glass fiber strand or strand product in a wet state are layered and continuously transported, and the continuously transported wet chopped strands are layered and transported continuously. A method of drying chopped glass fiber strands under a fluidized bed by blowing out and passing a large number of thin heated air streams through the strand layer from below. 2. Wet chopped strands obtained by cutting glass fiber strands or strand products in a wet state are layered and continuously transferred, and the continuously transferred wet chopped strand layer is coated with the wet chopped strands. The chopped strands of glass fibers are dried under a fluidized bed by ejecting and conducting a large number of thin heated air streams from below, and following the ejecting and conducting process of the heated air streams, the high temperature chopped strands are transferred. A large number of thin cooling air jets are ejected from below the pud strand layer,
A method for drying chopped strands of glass fiber in which the chopped strands are forcibly cooled at a high temperature under a fluidized bed by conducting electricity. 3. The jetting of the heated air stream, the jetting out of the heated air and cooling air discharged in the conduction process, the air discharged in the conduction process are collected together, dust removed, and then additionally heated to a desired temperature and continuously transferred. 3. A method as claimed in claim 2, in which the heated air stream is recirculated for drying the wet chopped strands below. 4. A perforated plate with a large number of small holes is integrated inside the device to dry the chopped strands by blowing and conducting heated air to the wet chopped glass fiber strands that are deposited and transferred in layers. arranged across the perforated plate; the upper part thereof defines an exhaust chamber for the heated air blown out through the small holes, and the lower part has at least one ventilation chamber for blowing out the heated air into the exhaust chamber through the small holes. said evacuation chamber has an opening in its surrounding wall for supplying wet chopped strands to one end region of said perforated plate, and a chopper on the opposite side of said opening and on said perforated plate. an opening for taking out the dried chopped strands formed at a level where the dried chopped strands can be discharged; and an exhaust port for discharging the heated air jetted from the ventilation chamber into the exhaust chamber through the small holes of the perforated plate. each of the vent chambers has at least one vent in its surrounding wall for receiving heated air from a heated air source; each of the exhaust vents and vents has an exhaust system; A blower system including an air heating device is connected; and in a position above the perforated plate, the chopped strands penetrate into the chopped strands and run or rotate in a plurality of fixed positions. 1. An apparatus for drying chopped strands under continuous transport and under a fluidized bed, characterized in that a transport device having a large number of rod-shaped bodies for stirring and transporting the chopped strands while forming them into a layer is disposed. 5. The device according to claim 4, wherein the air exhaust system and the heated air blower system are connected via a dust collector and remover. 6. The transfer device is substantially in contact with the perforated plate at an end region of the perforated plate where the wet chopped strands are fed and deposited from the supply port and at a position near the chopped strand removal opening. two rollers rotatably supported in parallel and orthogonal relation; an endless belt having a width comparable to that of the perforated plate, through which the heated air can pass substantially unimpeded; Claim 4 consisting of a large number of rods that successively enter as the belt rotates to form layers while stirring and transporting them, and that run through the formed layers as the belt rotates. Equipment described in Section. 7. The transfer device is arranged at a position near the end region of the perforated plate where the wet chopped strands are supplied and deposited from the supply opening and at a position near the cut-off opening for the chopped strands, and at any suitable position between the two positions. a plurality of rollers rotatably supported at suitable intervals in substantially parallel and orthogonal relation to the perforated plate; mounted so as to extend outwardly over the entire surface of the rollers; 5. The device according to claim 4, comprising a number of pins that rotate and enter the group of strands one by one as the roller rotates, stirring and transporting the strands while forming them into a layer. 8. A perforated plate having a large number of small holes for blowing out and conducting air to the wet chopped glass fiber strands deposited and transferred in layers is disposed integrally and transversely inside the device;
sandwiching the perforated plate, the upper part of which constitutes at least two ventilation chambers for discharging the air ejected through the small holes, and the lower part forming at least two ventilation chambers for ejecting air through the small holes into the exhaust chamber; The evacuation chamber has in its peripheral wall an opening for supplying wet chopped strands to one end region of said perforated plate, and on the opposite side of said opening and for discharging chopped strands on said perforated plate. an opening for taking out the dried chopped strands formed to the desired level, and connected to an exhaust system for exhausting the air ejected from the ventilation chamber through the small holes of the perforated plate to the exhaust chamber. It has an exhaust port;
Each of the at least one said ventilation chamber, except for the ventilation chamber adjacent to said outlet opening end wall of the chopped strand, is connected to a blower system each including an air heating device in its surrounding wall for receiving heated air. said vent chamber adjacent to the outlet opening end wall of the chopped strands has an opening connected to a cooling air blower system for receiving cooling air; Then, at a position above the perforated plate, the chopped strands are stirred while entering and running, or rotating at a plurality of fixed positions to form the chopped strands in a layer. An apparatus for drying chopped strands under continuous transport and under a fluidized bed, characterized in that a transport device having a large number of rod-shaped bodies for transport is disposed. 9. The device according to claim 8, wherein the air exhaust system and the heated air blower system are connected via a dust collector and remover.