Rapid dehydrating and drying method and device usable in low temperature

FIELD OF THE INVENTION
The present invention relates to a rapid dehydrating and drying method and device usable in low temperature with a high speed air stream, used for drying sheet-like articles such as mats, carpets, fabrics, cloths, non-woven fabrics, synthetic resin, glass, film, cardboard and other flat articles.
DESCRIPTION OF THE PRIOR ART
Mats, long-size cloths and sheets, and the like have commonly been dried naturally with ambient atmosphere, dried using heat, dehydrating and drying using centrifugal force, dried using ventilation, dehydrating and drying by pressurizing, and dried using a vacuum under reduced pressure. In vacuum drying under reduced pressure an article to be dried is placed in a chamber and is dried under reduced pressure. To lower the vapor pressure and to evaporate moisture contained in the article to be dried, vaporization heat is taken away. Therefore the article to be dried is cooled and becomes frozen. To prevent this, the article to be dried must be heated, which leads to defects because a great heat energy is necessary and a long period of time is needed for drying. Domesticuse foot mats and business-use door mats, etc., are particularly difficult to dry because various fibers are implanted on a reinforcing rubber sheet or textile fabrics are adhered to a rubber sheet and an air passage does not exist in the direction of the mat thickness. In hot air drying, an article to be dried is dried by evaporating water contained in the article using heating and ventilation. In this instance, a large amount of heat energy for evaporation is needed.
For uniform drying by heating during the manufacturing process of cloths such as long, wide, tight textile fabrics of natural and synthetic fibers, synthetic resin sheets and paper, precise temperature control is needed. At the same time in low temperature drying (below 50.degree. C.), it takes a long period of time. When tatami, thick mats made of rush and straw, and goza, thin rush mats, contain a lot of humidity due to high humidity during the rainy season, hot air of very high temperature (approximately 90.degree. C.) and high pressure (approximately 2000 mmAq) must be used in the prior hot air drying. There is a danger of heat deterioration of the article to be dried. In a dehydrating and drying method using centrifugal force, an article to be dried is put in a rapidly rotating drum to centrifugally remove water for dehydration. In this system, the dehydrated article should be dried again.
SUMMARY OF THE INVENTION
It is an object of the present invention to eliminate the above-mentioned prior art defects.
It is another object of the present invention to provide a continuous, rapidly dehydrating and drying device usable in low temperature which can continuously dehydrate and dry an article to be dried in low temperature (below approximately 60.degree. C.).
It is a further object of the present invention to remarkably shorten the time period necessary for dehydrating and drying, and greatly conserve energy without compromising the article to be dried.
It is yet another object of the present invention to use a high speed negative pressure air stream or combination of high speed negative pressure air stream and high speed air jet stream to obtain the above-mentioned objects.
The above-mentioned objects of the present invention, which dehydrate and dry wet articles such as textile fabrics, implanted sheets and carpets, especially mats with air-impermeable rubber sheet lining, are obtained by continuously sucking out water adhered to fiber gaps and water saturated and adhered to fibers by employing a strong negative pressure air stream at a sucking-out opening or in conjunction with a high speed air jet stream and high speed negative pressure air stream such that both streams join and the streams are further accelerated by using a sucking-out nozzle and a blowing nozzle.
The present invention also performs continuous and efficient drying by providing flanges (barriers) at the tip circumferences of the blowing nozzle and the sucking-out nozzle. The flanges prevent reciprocal short cuts between the high speed jet air stream and the high speed negative pressure air stream and between the atmosphere and each of the high speed jet air stream and the high speed negative pressure air stream. The high speed negative pressure air stream and the high speed jet air stream are adjacent to each other. Water drops adhered to fiber gaps of a mat and water saturated in and adhered to the fibers are transferred into the negative pressure zone of the sucking-out nozzle. The water drops are extracted from the fibers and become minute water drops on the high speed negative pressure air stream from the sucking-out nozzle. The water drops are then transferred upward from the root of the fibers and sucked out and exhausted by the sucking-out pipe.
In the present invention, dehydration means provides not more than 70% water removal from the article to be dried, dehydration/drying means provides 70-86% water removal from the article to be dried, and drying means provides 86-95% water removal from the article to be dried. Further, absolute drying means provides 95-100% water removal from the article to be dried. The above percentages are with respect to the ratio of water removal when the maximum water content of the article to be dried is 100%. For example, when the article to be dried has a maximum water content of 1 kg and 0.9 kg of water is removed, this is a case of 90% drying.
These objects, together with other objects and advantages which will be subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like reference numerals refer to like parts throughout.

BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a dehydrating and drying device according to the present invention using a component comprising a sucking-out nozzle and a blowing nozzle, both provided with flanges;
FIG. 2 is a perspective view of the component shown in FIG. 1;
FIG. 3 is an enlarged cross section of the component shown in FIG. 1;
FIG. 4 is a section of a dehydrating device according to the present invention using only a sucking-out nozzle with a flange;
FIG. 5 is a perspective view of a sucking-out nozzle shown in FIG. 4;
FIG. 6 is a vertical sectional view of the inner diameter D of the sucking-out nozzle shown in FIG. 5;
FIG. 7 is an enlarged cross section of a sucking-out nozzle with flanges contacting a mat whose fibers are covered with water membranes;
FIG. 8 is an enlarged cross section of surfaces of fibers of a mat covered with continuous water drops due to the negative pressure air stream from a sucking-out nozzle having flanges;
FIG. 9 is an enlarged drawing of continuous water drops becoming minute water drops by the negative pressure air stream from the sucking-out nozzle with flanges;
FIG. 10 is a cross section of the dehydrating device of the present invention shown in FIG. 4 using only the sucking-out nozzle without a flange;
FIG. 11 is a plan view of a sucking-out nozzle having a bottom surface of a flange provided with grooves according to the present invention;
FIG. 12 is a sectional view taken along the line B--B of FIG. 11;
FIG. 13 is a vertical sectional view showing a flange of a sucking-out nozzle having a cloth attached on its bottom face;
FIG. 14 is a sectional view of a water drop separating vessel;
FIG. 15 is a perspective view of a dehumidifier using a honeycomb rotor, a portion being broken away for the purpose of illustration;
FIG. 16 is an enlarged view of a mat having fibers covered with membranes of water contacting a component having a flange;
FIG. 17 is an enlarged view of fibers of a mat covered with continuous water drops due to a negative pressure air stream and an air jet stream of a component having a flange;
FIG. 18 is an enlarged view showing how water drops and water membranes change to minute water drops due to a negative pressure air stream and air jet stream of a component having a flange;
FIG. 19 is a cross section of a dehydrating and drying device according to the present invention when a blower is used;
FIG. 20 is a cross section of a dehydrating and drying device according to the present invention when two blowers are used, one for blowing air and the other for sucking-out water drops;
FIG. 21 is a cross section of a dehydrating and drying device using a sucking-out nozzle and a blowing nozzle, both without a flange;
FIG. 22 is a perspective view of a component used in FIG. 21 in the dehydrating and drying device according to the present invention;
FIG. 23 is a cross section of a mat whose fibers are coated with membranes of water contacting a component without a flange;
FIG. 24 is a cross section of a mat whose fibers are covered with continuous drops of water by the negative pressure air stream and the air jet stream from the component without a flange;
FIG. 25 is a cross section of a mat in which minute water drops are produced on the fibers of the mat by the negative pressure air stream and air jet stream from the component without a flange;
FIG. 26 is a sectional view of another embodiment of a dehydrating and drying device according to the present invention;
FIG. 27 is a plan view of a wire endless conveyor used in FIG. 26;
FIG. 28 is a plan view of a net-type endless conveyor used in FIG. 26;
FIG. 29 is a sectional view of a three stage dehydrating and drying device according to the present invention;
FIG. 30 is a plan view showing a modification of the component used in FIG. 29 of the present invention;
FIG. 31 is a sectional view taken along the line C--C in FIG. 30;
FIG. 32 is a partially enlarged view of FIG. 31;
FIG. 33 is a plan view showing a modification of the component used in FIG. 29 of the present invention;
FIG. 34 is a sectional view taken along the line D--D in FIG. 33;
FIG. 35 is an enlarged view of a portion of FIG. 34;
FIG. 36 is a vertical sectional view showing a modified component used in FIG. 29 according to the present invention;
FIG. 37 is an enlarged view of a blowing nozzle shown in FIG. 36 explained by deconstructing the vector R of jet stream into vectors R.sub.1 and R.sub.2 ;
FIG. 38 is a vertical sectional view of another modified component used in FIG. 29 according to the present invention;
FIG. 39 is a sectional view of a dehydrating and drying device of another embodiment according to the present invention;
FIG. 40 is a sectional view of a dehydrating and drying device of yet another embodiment according to the present invention;
FIG. 41 is an enlarged view of a part of a component to dehydrate and dry an article shown in FIG. 40;
FIG. 42 is a sectional view according to the present invention;
FIG. 43 is an enlarged sectional view of a mat;
FIG. 44 is a graph showing results of drying by a dehydrating and drying device using components with and without flanges according to the present invention;
FIG. 45 is a graph showing a result of two-stage drying using two components having flanges according to the present invention; and
FIG. 46 is a graph showing a result of three-stage dehydrating and drying using three sets of components having flanges.

DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 4 is an example of a dehydrating and drying device of the present invention using a water sucking-out pipe 3a. FIG. 5 is a perspective view of the sucking-out pipe 3a. A wet mat 1 having a large number of fibers 1a implanted in an air impermeable rubber sheet base material 1b is fixed as an article to be dried on a mobile stand 2. A sucking-out nozzle 3c of the sucking-out pipe 3a is provided with a flange 3e having a width of approximately 5-50 mm in its tip end circumference. The sucking-out nozzle 3c is placed so that it approaches or, preferably, touches and slides against the upper surface of the fibers 1a of the mat 1. The inlet of a blower 4 is connected to the sucking-out pipe 3a. The back surface of the base material 1b is heated, for example, by a plate heater Ph. The mat 1 is moved with the stand 2 at the speed of approximately 5-50 mm/sec. in the direction shown by the arrow P in FIG. 4. The zone that negative pressure reaches from the sucking-out nozzle 3c is generally considered to be within the area D (see FIG. 6) and negative pressure rapidly increases as the position gets closer to the area D near the sucking-out nozzle 3c. When the sucking-out nozzle is closed, the value of negative pressure in the sucking-out pipe becomes equal to that in the inlet of the blower 4. Negative pressure means pressure lower than atmospheric pressure (1 kg/cm.sup.2).
When the blower 4 is operated, water adhering to gaps of the fibers 1a of the mat 1 and laminar water (herein-after referred to as water membranes) impregnated into fibers 1a are sucked-up by the high speed negative pressure air stream Q at the sucking-out nozzle 3c of the sucking-out pipe 3a as shown in FIG. 7. The water becomes continuous water drops 13 (FIG. 8), and numerous minute water drops 14 (FIG. 9) at the surface of the fibers 1a due to surface tension of the water. The water drops are sucked out on the high speed negative pressure air stream into the sucking-out pipe 3a and the mat 1 is dried. In this case evaporation of water also takes place. Plate heater Ph is provided to heat and to accelerate the drying of the mat 1 to prevent lowering of the temperature of the mat 1 itself by the vaporization heat, especially in winter. As the flange 3e, provided at the tip end circumferential part of the sucking-out nozzle 3c, slides over the mat, outer air OA cannot flow directly into the sucking-out nozzle 3c, passing the surface of the flange 3e and contacting the fibers. But outer air OA does enter from under the flange 3e into the gaps of the fibers 1a of the mat 1 to the surface of the rubber sheet 1b, to become the negative pressure stream Q. The water mentioned above becomes minute water drops adhering from the bottom to the top of fibers 1a. The minute water drops are carried into the sucking-out nozzle 3c by the negative pressure air stream Q and discharged from the sucking-out pipe 3a.
In the above-mentioned embodiment, a dehydrating and drying device using one sucking-out pipe 3a having a water sucking-out nozzle 3c with a flange 3e in its tip end circumferential part is shown. It is possible to use a dehydrating and drying device with at least two sucking-out pipes 3a fixed in parallel to perform rapid dehydrating and drying several times faster than the case using one sucking-out pipe, by continuously dehydrating and drying in the manner set forth above.
FIG. 10 is a dehydrating and drying device as described as above but with a sucking nozzle 3c without a flange 3e at its tip end circumference. When there is no flange 3e, outer air OA enters readily from the bottom of the sucking-out nozzle 3c. This requires twice the drying time. In the present example, as the sucking nozzle 3c is arranged to upwardly generate the negative pressure air stream Q, in a direction against gravity, the negative pressure in the sucking-out nozzle 3c is preferably more than -800 mmAq. When the nozzle 3c is arranged to downwardly generate the negative pressure air stream Q, the negative pressure in the sucking-out nozzle 3c may be approximately -500 mmAq.
When an article to be dried has a dense, smooth surface such as, for example, cloths, mats, glass, synthetic resin film and metal sheet, is dried, as shown in FIGS. 11 and 12, numerous grooves 3k are installed in the direction of the bottom width of the flanges 3e and 3h provided in the tip end circumferential part of the sucking-out nozzle 3c. Because of the grooves 3k, the article to be dried does not stick up into the sucking-out nozzle 3c when being sucked as the outer air OA passes through the grooves 3k even when the wet article to be dried touches and slides along the sucking-out nozzle 3c. Thus dehydrating and drying at low temperature is possible while the article to be dried touches and slides along the sucking-out nozzle 3c and the outer air OA passes through the grooves 3k. Further, the article can be dehydrated and dried by increasing the negative pressure by attaching a porous cloth 3L at the bottom of the flanges 3e and 3h as shown in FIG. 13.
As shown in FIGS. 1, 2 and 3, a dehydrating and drying device using a component 3 is formed by providing a sucking-out nozzle 3c having a flange 3e in its circumferential part and adjacent to high speed jet blowing nozzles 3d having flanges 3f in their circumferential part. A water drop separating vessel 5 (FIG. 1) is provided between the sucking-out nozzle 3c and an inlet 4a of a blower 4.
The water drop separating vessel 5 is provided with a water drop discharging pump 7a at the bottom of the vessel and a filter 8 to catch water drops and dust as shown in FIG. 14.
A dehumidifier 6 is placed between the water drop separating vessel 5 and the inlet 4a of the blower 4 (FIG. 1). A rotary honeycomb type dehumidifier (FIG. 15) is preferably used as the dehumidifier 6. A pressure swing adsorption (PSA) system or thermal swing adsorption (TSA) system may also be used. The width W of the flanges 3e at the tip end circumferential part of the sucking-out nozzle 3c and the width W of the flanges 3f and 3h provided at the tip end circumferential part of the component 3 (FIGS. 2 and 3) is approximately 5-50 mm.
The mat 1 is put on a mobile stand 2 with the fibers 1a side up as shown in FIG. 1.
The component 3 is fixed and the mat 1 is conveyed along with the mobile stand 2 in the direction shown in the drawing as an arrow P at the speed of approximately 5-50 mm/sec. The upper surface of the fibers 1a of the mat 1 and the component 3 contact, press and slide against each other. The surface of the fibers 1a of the wet mat 1 after washing is covered with water membranes 12 as shown in FIG. 16. Water 12a is collected between the fibers 1a. When the blower 4 (FIG. 1) is operated, a high speed air jet stream R from the jet blowing nozzles 3d does not form a short cut with the negative pressure air stream Q and outer air OA directly near the surface of the flange 3e , but reaches deeply into the root of the fibers as shown by the dark arrows in FIG. 1. The high speed air jet stream R strongly blows downward on the water membranes 12 on the fibers 1a and on the water 12a between the fibers 1a, blows off the water membranes 12 on the fibers 1a downward, and flows together with the negative pressure zone at the sucking-out nozzle 3c. The high speed negative pressure air stream Q is accelerated by the multiplication effect of the high speed air jet stream R and the high speed negative pressure air stream Q, and transfers the water membranes 12 and water between the fibers 12a upward. Water membranes on the fibers 1a are divided into continuous water drops 13 by a dynamic pressure of the negative pressure air stream Q as shown in FIG. 17 and further into many minute water drops 14 as shown in FIG. 18. The water drops are sucked out on the high speed negative pressure air stream Q, and exhausted to the exterior to provide dehydrating and drying. Thus, the mat 1 is continuously dehydrated and dried.
In FIG. 16, if the flange 3e is not provided then the high speed air jet stream R takes a short cut along with the high speed negative pressure air stream Q as shown by the broken lines SO.
Minute water drops and water vapor sucked out on the high speed negative pressure air stream Q are sent into the water drop separating vessel 5. The cross sectional area of the water drop separating vessel 5 is remarkably wider than that of sucking-out pipe 3a as shown in FIG. 14, and the speed of the high speed negative pressure air stream Q decreases sharply in the water drop separating vessel 5. Therefore, water drops 14 fall from the air flow due to their own weight. Water A at the bottom of the vessel 5 is discharged to the exterior of the vessel using a positive-displacement pump 7A such as snake pump, Archimedes pump, monoflex pump, etc. Part of the water drops carried on the negative pressure air stream Q, (FIG. 14) and dust are filtered by the filter 8. Clean air Q.sub.2 (FIG. 15) is input to the dehumidifier 6 to be dehumidified and output as dry air Q.sub.3. The dehumidified air Q.sub.3 is input to the inlet of the blower 4. Pressurized air flow R.sub.D (FIG. 19) is output from the blower 4 to the blowing nozzles 3d. A high speed air jet stream R is strongly output from the blowing nozzles 3d to the fibers 1a of the mat 1 to provide continuous dehydrating and drying. In the water drop separating vessel 5, a rotary valve 7B, as shown by broken lines in FIG. 14, may be used in place of the positive-displacement pump 7A to discharge the water to the exterior of the vessel 5 and to pool the discharged water into a container 10. In this case, inter-vessel pressure P.sub.T and atmospheric pressure P.sub.OA are constantly isolated by the action of the rotating rotary valve 7B and a sealing plate 7C at the circumference of the rotary valve 7B.
In the dehumidifier 6, as shown in FIG. 15, a honeycomb dehumidifier rotor 61, capable of humidity adsorption, is held rotatably in a casing 62 and is rotated by a motor 63 and a drive belt 64 at a speed of approximately 10-20 r.p.h. Humid air Q.sub.2, from which water drops are separated in the water drop separating vessel 5 (FIG. 14), is input to a process zone 65 of the rotor 61 in the direction of the arrow by the blower 4 at the speed of approximately 1-3 m/sec. The moisture in the humid air Q.sub.2 is adsorbed and removed by the honeycomb rotor 61 to obtain dry air Q.sub.3, which is supplied to the blowing pipes 3b of the component 3 (FIG. 19) by the blower 4 to form the high speed air jet stream R.sub.D to accelerate drying. On the other hand, reactivation air RA, which is prepared by heating outer air OA up to approximately 100.degree.-140.degree. by the heater H, is passed through small channels of the reactivation zone 66 (shown by the arrow RA) in the opposite direction of the process air Q.sub.2 to continuously desorb, by heating, the humidity adsorbed in absorbing zone 65 and to discharge it as exhaust air EA. Thus the absorbing zone 65 continuously supplies dry air Q.sub.3 changed from process air Q.sub.2 to the blowing pipes 3b.
A flow pattern of the case when a single blower is used is shown in FIG. 19. When the temperature of the dry air Q.sub.3 from the dehumidifier is low, the dry air Q.sub.3 is input to a blower 4 and then input a heater H.sub.2 to heat the air to 40.degree.-80.degree. C. and to lower the air's relative humidity to obtain a high speed air jet stream R to blow against the mat 1 to promote drying.
FIG. 20 shows a flow pattern of a case when an air blowing blower 4d, a water drop sucking-out blower 4s and a dehumidifier 6 are used. The sucking-out blower 4s is connected to the sucking-out pipe 3a of the component 3. Exhaust air EA containing water drops that were sucked out by the blower 4s is exhausted into the outer air OA.
A rotary dehumidifier 6 is placed in the pre-stage of the inlet of the blower 4d. The outlet of the blower 4d and the blowing pipes 3b of the component 3 are connected via the heater H.sub.2. Outer air OA is input to the dehumidifying zone of the dehumidifier 6 to remove humidity in the outer air OA. The outer air OA is pressurized by the blower 4d, is heated by the heater H.sub.2 and a dry high speed air jet stream R from the heater H.sub.2 is strongly blown into the wet mat 1 from the blowing nozzles 3d to speedily dry the mat 1. In this case, the time for drying can be shortened approximately 40% compared with the case when the dehumidifier 6 is not provided.
When the mat 1 to be dried is wet after being washed with a volatile liquid other than water, a volatile liquid vapor (VOC) adsorbing and removing device 6 voc instead of the dehumidifier 6 is used as shown in FIGS. 19 and 20.
In this case, a honeycomb rotary type adsorbing and removing device is used, for example, as the adsorbing and removing device, and a honeycomb rotor carrying active carbon, hydrophobic zeolite, etc., as adsorbent is used. The honeycomb rotary type adsorbing and removing device 6voc, like the dehumidifier 6 shown in FIG. 15, has a VOC adsorbing zone 65 and a VOC desorbing zone 66. It continuously adsorbs VOC in the air Q.sub.2 (FIG. 19) from the gas-liquid separating vessel 5 (FIG. 14) to obtain clean air Q.sub.3. The clean air Q.sub.3 is used as an air jet stream R to continuously dry the mat 1. The blower 4 is operated and organic solvent in the wet mat 1 is sucked out by the sucking-out nozzle 3c of the component 3 as shown in FIG. 19. Air is passed in a gas-liquid separating vessel 5, air containing organic solvent vapor(s) is input to the adsorbing zone 65 of the honeycomb rotary type adsorbing and removing device and clean air Q.sub.3 which has the organic solvent vapor(s) removed is sucked into an inlet of a blower 4 and pressurized and heated by heater H.sub.2. The air is strongly blown onto the wet mat 1 as a high speed air jet stream R from the blowing nozzles 3d of the component 3 to dry the wet mat 1. In this honeycomb rotary type adsorbing and removing device 6voc, outer air OA is heated to approximately 120.degree.-180.degree. C. and input to its reactivation zone as reactivation air RA. Concentrated VOC adsorbed at the adsorbing zone 65 becomes an exhaust air, and is discharged into the outer air OA.
In the case of drying a mat 1 washed with a mixture of a volatile liquid and water, a honeycomb adsorbing and removing device using a rotary type VOC adsorbing and removing element containing an adsorbent which removes water such as hydrophilic zeolite and hydrophobic zeolite may be used.
A component 3 has been shown in which a sucking-out nozzle 3c and a blowing nozzle 3d are adjacent each other as shown in FIGS. 1 and 2. However, a component comprising a sucking-out pipe 3a containing a sucking-out nozzle 3c with a built-in blowing pipe 3b containing a blowing nozzle 3d or a component comprising a blowing pipe 3b containing a blowing nozzle 3d with a built-in sucking-out pipe 3a containing a sucking-out nozzle 3c can be used to achieve approximately the same action and effects.
FIGS. 21 and 22 show a dehydrating and drying device using a sucking-out nozzle 3c and blowing nozzles 3d , both without flanges. The actions of a high speed air jet stream R and a high speed negative pressure air stream Q in the component 3 are shown in FIGS. 23, 24 and 25. Water membranes 12 on the fibers 1a of the mat 1 and water 12a at the gaps of the fibers 1a shown in FIG. 23 gradually become continuous water drops 13 as shown in FIG. 24 and change to many minute water drops 14 as shown in FIG. 25. The action of the high speed air jet stream R and high speed negative pressure air stream Q when flanges are provided are described in detail in FIGS. 16, 17 and 18. When flanges are not provided, the high speed air jet stream R and high speed negative pressure air stream Q take a short cut at the tips of the nozzles 3a, 3b , 3c and 3d. Also, both streams and the outer air are short cut at the tips of the nozzles 3a, 3b, 3c and 3d. Thus, only a small amount of the high speed air jet stream R and a small amount of the high speed negative pressure air stream Q can reach the roots of the fibers 1a. This decreases the efficiency of drying compared with the case when flanges are provided.
As shown in FIG. 26, a rapid dehydrating and drying device usable in low temperature comprises a wire endless conveyor 16 installed among a driving pulley 18, a driven pulley 19, a tension pulley 20 and driven pulleys 21 and 22. A component 3 is formed with a sucking-out nozzle 3c and blowing nozzles 3d , provided in one body and is placed under the conveyor 16. As shown in FIG. 27, the conveyor 16 is an endless conveyor with many wires 16c placed at appropriate intervals. Grooves are provided on the driving pulley 18 and the driven pulley 19 at the same intervals as the intervals between the wires so that the wires can fit onto the driving pulley 18 and the driven pulley 19. Instead of using the wire endless conveyor 16, a net-type endless conveyor 15 having a large opening ratio having a mesh of 10 mm by 10 mm as shown in FIG. 28 may be used.
In FIG. 26, the sucking-out nozzle 3c is connected to the inlet of the water drop separating vessel 5 by a duct Sp.sub.1, blowing nozzles 3d are connected to the outlet of the blower 4 by a duct Dp, and the outlet of the water drop separating vessel 5 and the inlet 4a of the blower 4 are connected by a duct Sp.sub.2 via the dehumidifier 6. Plural pressing rollers 15e are placed at positions to press down the article to be dried, e.g., mat 1, to prevent the mat 1 from rising by the strong air jet stream from the blowing nozzles 3d of the component 3. Plural pressing rollers 15e are connected together by chains 17.
The action of this embodiment shown in FIG. 26 will be explained. A mat 1 is placed with its fibers 1a side down between the conveyor 16 and the pressing rollers 15e. The conveyor 16 and pressing rollers 15e are moved by motors M and Ma in the direction of the arrow P at a speed of 6-10 mm/sec. The jet stream blows strongly from the blowing nozzles 3d at fibers 1a of the mat 1 by the action of the blower 4, so that the stream goes into fibers 1a of the mat 1. Water drops and water in the fibers 1a of the mat 1 are intensely and speedily sucked out from the sucking-out nozzle 3c by the high speed negative pressure air stream Q accelerated by the multiplication effect of the air jet stream R and negative pressure air stream Q at the sucking-out nozzle 3c, to provide continuous drying. In this case, static pressure in the sucking-out nozzle 3c is approximately -800--1500 mmAq and static pressure in the blowing nozzle 3c is approximately +800-+1500 mmAq.
The component 3 used in this example is the component as shown in FIG. 22. The component 3 is a component without flanges to prevent the short cut of air flow. When a component with flanges as shown in FIG. 1 is used, drying time is decreased and the energy saving effect is greater than in the case of using a component without flanges.
In the present embodiment, a component in which a sucking-out nozzle 3c and blowing nozzle 3d are formed in one body is used. The sucking-out nozzles 3c and the blowing nozzle 3d may be separately and closely arranged.
As shown in FIG. 29, a wire endless conveyor 16, is driven in the direction shown by the arrow P as in FIG. 26. The belt conveyor 15b is driven by a driving motor Ma via a driving pulley 18a at the same speed as the conveyor 16 in the direction shown by the arrow. The mat 1 is between the conveyor 16 and the belt conveyor 15b. Plural rollers 15e are on the reverse side of the belt conveyor 15b and press an article to be dried.
The first dehydrating device 30 comprises a component 3 including two sucking-out nozzles 3c and one blowing nozzle 3d. Both the sucking-out nozzles 3c and the blowing nozzle 3d are provided with flanges 3e, 3f and 3h (see FIG. 2). The two sucking-out nozzles 3c are located at both sides of the blowing nozzle 3d and combined as shown in the drawing. A sucking-out blower 4s.sub.1 has an inlet connected with the sucking-out nozzles 3c by a duct Sp.sub.1. A blowing blower 4d.sub.1 has an outlet connected with the blowing nozzle 3d by a duct Dp.sub.1.
The second drying device 40 includes a component 3B as shown in FIG. 2, a blowing blower 4d.sub.2 having an outlet connected with the blowing nozzles 3d of the component 3B by a duct DP.sub.2 and via a heater H. A dehumidifier 6 is located at the front of the inlet of the blower 4d.sub.2. A sucking-out blower 4s.sub.2 has an inlet connected to the sucking-out nozzle 3c by a duct SP.sub.2.
The third drying device 50 uses the component 3B used in the second drying device 40. The inlet of a blower 4 is connected to the sucking-out nozzle 3c of the component 3B by a duct SP.sub.3 via a water drop separating vessel 5 and a dehumidifier 6A. The outlet of the blower 4 is connected to the blowing nozzles 3d of the component 3B by a duct DP.sub.3 via a heater H.
The operation of the device shown in FIG. 29 will now be explained. A driving pulley 18 of the wire endless conveyor 16 and a driving pulley 18a of the belt conveyor 15b are driven to move both conveyors 15b and 16 at the same speed in the direction P as shown in the drawing. Mat 1 is kept between the conveyors 15b and 16 with its fibers 1a set downward, to provide dehydrating and drying.
In the first dehydrating device 30, the blowing blower 4d.sub.1 and the sucking-out blower 4s.sub.1 are operated, a high speed negative pressure air stream is accelerated by the multiplication effect of the high speed air jet stream and the high speed negative pressure air stream, water on the fibers of the mat 1 is sucked out as minute water drops by the sucking-out nozzles 3c, and the air stream is exhausted from the sucking-out blower 4s.sub.1 to continuously dehydrate the mat 1. In this case, the static pressure in the sucking-out nozzle 3c of the component 3A is as high as approximately -1300 mmAq, and the static pressure in the blowing nozzle is approximately +500-+800 mmAq to remove approximately 70-86% of the maximum water content.
Then, the mat 1, dehydrated at the first dehydrating device 30, is transferred between conveyors 15b and 16 and is dried by a component 3B of the second drying device 40. In the second drying device 40, humidity in the outer air is removed by the dehumidifier 6, dried air is heated to approximately 60.degree. C. by the heater H, and the air is blown into the roots of the fibers 1a of the mat 1 as a hot and dry high speed air jet stream from the blowing nozzles 3d to provide drying. The water remaining after the dehydration in the first stage is removed. The ratio of removed water is approximately 86%-90%. In this case, the static pressure in the sucking-out nozzle 3c is approximately -500--800 mmAq and the static pressure in the blowing nozzle 3d is as high as +1300 mmAq.
The mat 1 is then conveyed to the third drying device 50. In the third drying device 50 a hot and low-humidity high speed air jet stream is blown into the fibers 1a of the mat 1 by the action of a blower 4, and the remaining water is quickly sucked out by the sucking-out nozzle 3c of the component 3B. The water drops and dust in the air stream are removed at the water drop separating vessel 5, the air stream is dried to a dew point of approximately -20.degree. C. to -50.degree. C. by the dehumidifier 6A, dried air is input to the heater H from the outlet of the blower 4 and heated to approximately 80.degree. C., the air is again blown strongly into the fibers 1a of the mat 1 as a hot and low-humidity high speed air jet stream from blowing nozzles 3d and the high speed air jet stream is accelerated to remove a very small quantity of water remaining in the fibers 1a to complete the third drying operation. During the third drying operation approximately 90-95% of the water contained in the mat 1 is removed. In this case, the static pressure in the sucking-out nozzle 3c is approximately -700 mmAq and the static pressure in the blowing nozzle is approximately +1500 mmAq. An absolute drying of approximately 100% can be achieved by regulating the static pressures in the sucking-out nozzle and in the blowing nozzle 3d in each component 3 as described above. This results in a great energy saving.
In the third drying device 50, a blower for circulating air flow is used. A sucking-out blower 4 may be used and a blowing blower 4d.sub.3 may be used as shown by the broken lines in the drawing. In this case, the sucked-out air may be discharged as an exhaust air EA from the outlet of the sucking-out blower 4. Outer air OA may be dehumidified by a dehumidifier 6B arranged at the front of the inlet of the blowing blower 4d.sub.3, as shown by the dotted lines. The resulting dry air may also be heated by the heater H to act on both blowing nozzles 3d. In this case the dehumidifier 6A is not necessary.
Another modified example of the component 3 used in the present invention is shown in FIGS. 30, 31 and 32. FIG. 30 shows a component 3 having sucking-out nozzles 3c and blowing nozzles 3d, alternately arranged. FIG. 31 is a cross sectional view of FIG. 30 taken along the line C--C. Each sucking-out nozzle 3c and each blowing nozzle 3d are provided with flanges 3e, 3f and 3h at their circumferences and grooves 3n are provided on the plane of the flanges. An article to be dried is slid in the direction crossing the air flow. Thus, as shown in FIG. 32, the tips of fibers 1a of the mat 1 penetrate into the grooves 3n to increase the resistance of air flow. The nozzle surface is also pressed strongly to the mat surface and deviation of the high speed air streams can be prevented by the grooves 3n.
FIGS. 33, 34 and 35 show another example of the component 3. FIG. 33 is a plan view of the component 3, FIG. 34 is a cross sectional view of FIG. 33 taken along the line D--D, and FIG. 35 is an enlarged view of FIG. 34. A plate 3m having many small holes 3r arranged in a zigzag configuration is attached at the tip of an opening of blowing pipes 3b adjacent to both sides of the sucking-out pipe 3a. Thus, the small holes 3r act as separate blowing nozzles. A high speed air jet stream R is blown out intermittently from the small holes 3r and the jet stream easily penetrates into minute gaps in the fibers 1a of the mat 1.
In FIGS. 33, 34 and 35, the blowing nozzle 3d is constructed such that the high speed air jet stream R gushes out perpendicular to the article to be dried. As shown in FIG. 36, the blowing nozzle 3d may be constructed such that the high speed air jet stream R gushes out obliquely to the conveying direction of the article to be dried. As shown by the vector in FIG. 37, which is an enlarged view of FIG. 36, the force of the high speed air jet stream R can be considered as a component of the force R.sub.1 to the direction of conveying the article to be dried and a component of force R.sub.2 perpendicular to R.sub.1. The component of the force R.sub.1 contributes to transferring the article to be dried along the wire endless conveyor 16 to conserve energy. In contrast, if the blowing nozzle 3d is constructed such that the high speed jet stream R gushes out obliquely in a direction opposite to the transferring direction of the article to be dried as shown in FIG. 38, dehydrating and drying efficiency increases compared with the case when the high speed air jet stream gushes out perpendicular to the article to be dried.
A modified embodiment of the dehydrating and drying device according to the present invention is shown in FIG. 39. The wet mat 1 is transferred between the wire endless conveyor 16 and pressing rollers 15e. The mat 1 is dehydrated and dried by a pre-stage dehydrating device 70 including two components 3 having a sucking-out nozzle 3c and blowing nozzles 3d both without flanges and by a post-stage drying device 80 including two components 3 the same as those in the pre-stage dehydrating device 70. In this case, a blower 4sfor sucking-out and a blower 4d for blowing are used in the pre-stage dehydrating device 70 to increase the dehydrating efficiency. In the post-stage dehydrating device 80 blower 4 is used for circulating the air. A water drop separating vessel 5 and a dehumidifier 6 are arranged in front of the blower 4 in the post-stage drying device 80 to increase the drying efficiency.
A component 3 including one or more sucking-out nozzle(s) 3c and one or more blowing nozzle(s) 3d may be used according to the materials, sizes, thicknesses, etc., of the articles to be dried. Also, plural components 3 may be used to dehydrate and dry in plural stages. In this case, two blowers, one for sucking-out and one for blowing, may be used, or a blower for circulating may be used. Static pressures in the sucking-out nozzle 3c and in the blowing nozzle 3d may be controlled at will.
Referring to FIG. 40, an embodiment of the present invention for drying an article such as a carpet through which air can pass in the direction of its thickness is described. A wire endless conveyor 16a is installed among a driving pulley 10 and a driven pulley 11. A wire endless conveyor 16 is installed among a driving pulley 12 and a driven pulley 13. An article to be dried such as a wet carpet 1A is held between the lower part of the conveyor 16a and the upper part of the conveyor 16, and is carried in the direction shown by the arrow P.
As shown in FIG. 41, a sucking-out nozzle 3c having a flange 3e in its circumferential part and a blowing nozzle 3d having a flange 3f in its circumferential part are arranged opposite each other at a position where they touch and slide on the surfaces of an article to be dried 1A. The conveyors 16a and 16 are located therebetween.
The sucking-out nozzle 3c is connected to the inlet of the water drop separating vessel 5 by a duct Sp.sub.1. The outlet of the water drop separating vessel 5 and the inlet of the blower 4 are connected by a duct Sp.sub.2 via a dehumidifier 6. The outlet of the blower 4 and the blowing nozzle 3d are connected by a duct Dp.
The action of the embodiment in FIG. 40 is now explained. The conveyors 16 and 16a are driven at the same speed by motors M and Ma. An air-permeable wet carpet 1A is placed on the conveyor 16 and is moved in the direction shown by the arrow P at a speed of approximately 5-50 mm/sec. The carpet 1A, held between the two conveyors 16 and 16a, is carried to a position where the sucking-out nozzle 3c and the blowing nozzle 3d are in counter positions.
As shown in FIG. 41, when the blower 4 is operated, the high speed air jet stream R gushes out from the high speed jet blowing nozzle 3d which is placed so that it touches and slides on the lower surface of the upper part of the conveyor 16. The high speed air jet stream R changes water contained in the carpet 1A into water drops and forces the water drops and water vapor upward to the top of the carpet 1A. The high speed air jet stream R flows into the negative pressure air stream region, and water drops and water vapor are sucked out from the sucking-out nozzle 3c by the high speed negative pressure air stream Q.
Air containing minute water drops are input to the water drop separating vessel 5. The air from which water drops and dust have been removed is input to the dehumidifier 6. The obtained dry air is input again to the blowing nozzle 3d by the blower 4. Continuous drying can be performed by continuing the above operation.
FIG. 42 shows another embodiment of the present invention which includes a pre-stage conveying apparatus 100 and a post-stage conveying apparatus 110. Both apparatuses convey a mat 1 as an article to be dried. A dehydrating and drying part 90 is also provided. The pre-stage conveying apparatus 100 comprises a driving pulley 18, driven pulleys 19, 21 and 22, and an endless conveyor 15c coupled to the driving pulley 18 and the driven pulleys 19, 21 and 22. The post-stage conveying apparatus 110 comprises plural driving rollers 15h for conveying the article to be dried. The dehydrating and drying part 90 comprises an endless conveyor belt 15b, rollers 15g to hold and convey the mat 1, blowing nozzles 3d and a sucking-out nozzle 3c. The blowing and sucking-out nozzles 3d and 3c, respectively have flanges 3e and 3f at the circumference of tips inserted between the conveying rollers 15g and are placed at positions to contact and slide on the surface of fibers 1a of the mat 1. An outlet of a blowing blower 4d and the blowing nozzles 3d are connected by a duct Dp via a heater H. An inlet of sucking-out blower 4s and the sucking-out nozzle 3c are connected by a duct Sp via a water drop separating vessel 5.
A mat 1 is placed on the conveyor 15c of the pre-stage conveying apparatus 100 so that the fibers 1a of the mat 1 face downward, the driving pulley 18 is driven by a driving motor M to move the conveyor 15c in the direction shown by the arrow P to convey the mat 1 to the dehydrating and drying part 90. The mat 1 is dehydrated and dried as shown in FIG. 40 at the dehydrating and drying part 90 by the action of blowing nozzles 3d and a sucking-out nozzle 3c. Thereafter, the dehydrated and dried mat 1 is conveyed in the direction shown by the arrow P to the post-stage conveying apparatus 110 by driving rollers 15h for conveying the article to be dried, to complete the dehydrating and drying process. In this case, driving rollers 15h for conveying the article to be dried are driven by driving motors M.sub.1, M.sub.2 . . . .
In the post-stage conveying apparatus 110, an endless conveyor may be used instead of driving rollers 15h for conveying.
In the present embodiment shown in FIG. 42, two blowing nozzles 3c and a sucking-out nozzle 3d are arranged between conveying rollers 15g. The number and arrangement of the nozzles may be selected at will according to the sizes and kinds of article to be dried.
The dehydrating and drying method according to the present invention provides dehydrating and drying by employing a multiplication effect due to a combination of a high speed air jet stream and a high speed negative pressure air stream in accordance with a novel concept and principle. The present invention dehydrates and dries an article by changing the water contained in the article to be dried into minute water drops by the dynamic pressure of the high speed air jet stream R and the sucking force of the negative pressure air stream Q, with little vaporization heat energy of the water. The dehydration and drying occurs with less energy, less time, and at a lower temperature than prior art devices and without injuring the article to be dried.
A method of drying an implanted mat with a rubber sheet lining is described with respect to FIG. 43. This type of mat is the most difficult type of article to dry.
With respect to the embodiment of the present invention shown in FIGS. 7, 8 and 9, drying this type of mat occurs by using a dehydrating device comprising a sucking-out nozzle 3c having flanges at the tip of its circumference. The principle of the dehydration process is now explained. Water membranes 12 change to continuous water drops 13 by the high speed negative pressure air stream Q. The sucking force of the sucking-out nozzle 3c overcomes the surface tension and the viscosity of the water drops 13. The water drops are subdivided into minute water drops 14 as shown in FIG. 9. The water drops 14 are extracted from the fibers 1a and sucked into the sucking-out pipe 3a by the high speed negative pressure air stream and externally exhausted with the water vapor. As mentioned above, water drops 14 on the mat 1 are continuously sucked out and removed from the roots of the fibers 1a to dehydrate the mat 1 by using the sucking-out nozzle 3c having a flange 3e.
As stated above, FIGS. 21, 23, 24 and 25 show an embodiment of the present invention in which drying using a component 3 comprises a contiguous sucking-out nozzle 3c and blowing nozzles 3d. The principle of this dehydrating and drying method is now explained. The high speed air jet stream R flows in the high speed negative pressure air stream region and is accelerated by a multiplication effect of the high speed air jet stream R and the high speed negative pressure air stream Q. The negative pressure air stream has a strong sucking force on the group of fibers. The water membrane 12 on the fibers and the water 12a between the fibers (FIG. 23) changes to continuous water drops 13 (FIG. 24) by a multiplication effect of the dynamic pressure of the high speed air jet stream R and sucking force of the high speed negative pressure air stream Q between the fibers. The water drops 13 overcome the surface tension and the viscosity of the water and are subdivided into minute water drops 14 (FIG. 25). These water drops 14 are extracted from the fibers 1a and sucked into the high speed negative pressure air stream Q in the sucking-out nozzle 3c and externally exhausted with the water vapor. This results in a dry article.
Drying using a sucking force from only the sucking-out nozzle 3c requires several times the time compared with the case of drying with a component 3 comprising a sucking-out nozzle 3c and blowing nozzle(s) 3d.
The curve 3 in the graph of FIG. 44 shows the result of a drying test according to the embodiment of the present invention shown in FIGS. 21, 23, 24 and 25, in which the size of the implanted mat, i.e., the article to be dried, is 1m.times.1m, the transferring speed of the implanted mat is 8.3 mm/sec., the jet stream temperature is 50.degree. C., the static pressure in the sucking-out nozzle 3c is -1300 mmAq, the static pressure in the blowing nozzle 3d is +1300 mmAq, and the component 3 is not provided with a flange. The mat weighed 1000 g before washing and 1800 g after washing. Therefore, the wet mat contained 800 g of water. The drying ratio is as given by the following formula: ##EQU1##
The principle of dehydrating and drying a wet mat 1 using a component 3 comprising a sucking-out nozzle 3c and blowing nozzles 3d, both provided with flanges 3e , 3f and 3h at there tips as shown in FIG. 1, is described in detail above with respect to FIGS. 21, 23, 24 and 25.
Flanges 3e, 3f and 3h are provided at the tip end circumferences of the component 3. The high speed air jet stream R passes over the surfaces of the flanges 3e , 3f and 3h contacting the tips of the fibers 1a of the mat 1 and does not form a short cut with the high speed negative pressure air stream Q. Rather, the high speed air jet stream R flows deeply and reaches to the roots of the fibers compared with the case in which a component without flanges is used. Since the jet stream R and negative pressure stream Q do not form a short cut with the outer air, static pressure in the nozzles does not drop, the high speed air jet stream R flows into the negative pressure air stream region, the high speed negative pressure air stream Q is accelerated by the multiplication effect of both streams and sucks out the water drops and water vapor from the sucking-out nozzle 3c to provide continuous dehydrating and drying of the article. The drying time can be shortened approximately 30% compared with the case in which the component 3 without flanges is used (FIG. 44).
As described in the embodiment of the present invention shown in FIG. 29, in the component 3 comprising a sucking-out nozzle 3c and blowing nozzles 3d, both having flanges, when the component 3 is designed such that a high speed air jet stream R flows obliquely with respect to the mat 1 (FIGS. 36-38), it contributes to transferring the article to be dried and a higher dehydrating and drying efficiency can be obtained.
In FIG. 29, when only the second stage dehydrating and drying device 40 is used, the drying ratio is shown as line 4 in the graph of FIG. 44.
In FIG. 44, curve 4 shows data when a component 3B with flanges is used as shown in FIG. 29, and curve 3 shows data when a component without flanges is used. In the former case 84 seconds was needed for achieving the drying ratio of 96%, and in the latter case 120 seconds was needed for achieving the same drying ratio.
In FIG. 44, curve 1 shows data when the dehydrating and drying process employed only a high speed negative pressure air stream Q with a sucking-out nozzle 3c without flanges in its circumference, and curve 2 shows data when the dehydrating and drying process employed only a high speed air jet stream R with a blowing nozzle 3d without flanges in its circumference. The data in FIG. 44 show that drying by a high speed negative pressure air stream Q in the sucking-out nozzle 3c provides an increased drying ratio at the former half stage of the drying and that drying by a high speed air jet stream R with the blowing nozzle 3d provides an increased drying ratio at the latter half stage of the drying process. In FIG. 44, the dehydrating and drying conditions are as follows:
static pressure in the sucking-out pipe: -1300 mmAq
static pressure in the blowing pipe: +1300 mmAq
size of the implanted mat: 1 m.times.1 m
thickness of the implanted mat: fibers 7 mm and base 3 mm
conveying speed of the implanted mat: 8.3 mm/sec.
temperature of the jet stream: 50.degree. C.
weight of the mat containing water: 1800 g
(1000 g (net weight of mat)+800 g (water)=1800 g)
outer air: temperature 25.degree. C., relative humidity 54%.
In FIG. 29, when the dehydrating and drying devices 30 and 40 are used, the drying ratios are shown in the graph of FIG. 45, in which two components 3A and 3B have flanges at the tip end circumferences and drying was performed in two stages. In FIG. 45, the dehydrating and drying conditions are as follows:
sucking-out negative pressure at the first stage: -1500 mmAq
sucking-out negative pressure at the second stage: -300 mmAq
static pressure in the blowing nozzle at the first stage: +300 mmAq
static pressure in the blowing nozzle at the second stage: +1500 mmAq
size of the implanted mat: 1 m.times.1 m
thickness of the implanted mat: fibers 7 mm and base 3 mm
conveying speed of the mat: 12 mm/sec.
temperature of the jet stream at the first stage: 50.degree. C.
temperature of the jet stream at the second stage: 60.degree. C.
net weight of the mat (FIG. 43): 1000 g
maximum water content of the mat: 800 g
weight of the wet mat: 1800 g
water content ratio: 80%
outer air: temperature 25.degree. C., relative humidity 54%.
The wet mat 1 is dehydrated in the first stage dehydrating device and at the same time conveyed. It is then dried in the second stage drying device. When dehydration and drying were provided for 83 seconds, 768 g out of 800 g of water could be removed to achieve a drying ratio of 96%.
Therefore, at the first stage dehydration the pressure of the high speed negative pressure air stream Q is raised (-1500 mmAq) and the pressure of the high speed air jet stream R is weakened (+300 mmAq). At the second stage drying the pressure of high speed air jet stream R is raised (+500 mmAq) and the pressure of the high speed negative pressure air stream Q is weakened (-300 mmAq) to improve the drying efficiency and to save energy.
FIG. 46 shows data of the three stage drying using three components A, 3B and 3B having flanges at their tip end circumferences and using dehydrating and drying devices 30, 40 and 50 as shown in FIG. 29. In FIG. 46, the dehydrating and drying conditions are as follows:
sucking-out negative pressure at the first stage: -1500 mmAq
sucking-out negative pressure at the second stage: -700 mmAq
sucking-out negative pressure at the third stage: -300 mmAq
static pressure in the blowing nozzle at the first stage: +300 mmAq
static pressure in the blowing nozzle at the second stage: +1300 mmAq
static pressure in the blowing nozzle at the third stage: +1500 mmAq
size of the implanted mat: 1 m.times.1 m
thickness of the implanted mat: fibers 7 mm and base 3 mm
conveying speed of the mat: 15.6 mm/sec.
temperature of the jet stream at the first stage: 40.degree. C.
temperature of the jet stream at the second stage: 50.degree. C.
temperature of the jet stream at the third stage: 65.degree. C.
net weight of the mat: 1000 g
maximum water content of the mat: 800 g
weight of the wet man: 1800 g
outer air: temperature 25.degree. C., relative humidity 54%.
The wet mat was dehydrated in the first stage dehydrating device 3A and then dried in the second and third stage drying devices 3B. When dehydration and drying was provided for 64 seconds, a drying ratio of 96% was achieved.
As described above, the static pressure in the sucking-out nozzle 3c is raised at the pre-stage to suck out and remove most of the water and is lowered at the latter stage. On the other hand, the static pressure in the blowing nozzle 3d is lowered at the pre-stage and raised at the latter stage to remove the remaining water after the pre-stage dehydrating. This provides efficient drying and saves energy.
The energy necessary for this dehydrating and drying process requires five blowers of 3.3 KWH, a heater for heating an air jet stream R of 3 KWH and a driving motor of 0.5 KWH. This sums up to approximately 20 KWH which costs 400 yen/hour when the electricity rate is calculated at approximately 20 yen per 1 KWH. The drying time per 1 m.times.1 m mat mentioned above is approximately 60 seconds which means it costs approximately 6.6 yen. This is an extremely low electricity cost.
The above examples were explained using, as articles to be dried, a mat having a base material comprising a rubber sheet and an air-permeable carpet. The present invention is not limited to these material and can be used for wide carpet, cloths, fabrics such as woven fabrics, non-woven fabrics, glass fiber sheet, synthetic fiber sheet, other long sheets, artificial turf, thin mats of rush, thick mats of rush and straw, cardboard, fire hose and electronic parts requiring drying at low temperature after washing and of course for drying during a manufacture process of any of the above.
In drying a mat, prior dehydrating drying using centrifugal force, drying by using both pressure decrease and hot air, and simple heat drying are used. However, uniform drying cannot be achieved and drying must be performed at a rather high temperature of 80.degree.-120.degree. C. during drying using heat. Some types of cloth need to be dried at temperatures lower than 50.degree. C. This requires a long time in low-temperature drying. In the dehydrating and drying device of the present invention using a high speed negative pressure air stream Q, water adhered to the fiber surface and fiber gaps is evaporated and physically extracted by negative pressure near the sucking-out nozzle 3c, for example, by a high speed negative pressure air stream Q of approximately -300 mmAq to -1500 mmAq. Minute water drops are removed by the negative pressure air stream Q, the temperature of an article to be dried by water vaporization is not decreased, a high speed drying in low temperature is achieved, the device is simplified, heating energy is not great, money is saved and an extremely high drying efficiency is achieved.
When a high speed negative pressure air stream Q of the sucking-out nozzle 3c and a high speed air jet stream R from the blowing nozzle 3d are used in the present invention, dry air as the high speed air jet stream R is blown at numerous fiber gaps to the fiber root to promote drying and at the same time the air jet stream blows into the negative pressure stream zone near the sucking-out nozzle 3c to transfer water instantaneously into the sucking-out nozzle 3c due to a multiplication effect of the high speed negative pressure air stream Q and the high speed air jet stream R. As drying is performed in this manner, the drying efficiency is increased. The drying efficiency is further increased, of course, when hot air of approximately 40.degree.-65.degree. C. is used as the high speed air jet stream R. Compared with energy use in a case of drying by blown hot air in the prior art for example, it was observed that the energy use is decreased by half by using a dehydrating and drying device of the present invention which uses both the sucking-out nozzle 3c and the jet blowing nozzle 3d.
When a dehydrating and drying device of the present invention is used, dehydrating and drying can be provided by using only a sucking-out nozzle 3c in the apparatus shown in FIG. 39, depending on the type of article to be dried. On the other hand, dehydrating and drying can be provided by using only a blowing nozzle 3d.
By dividing the dehydrating and drying device of the present invention into a preceding-stage dehydrating device which dehydrates in a preceding zone and a following stage drying device which performs drying in a following zone as shown in FIGS. 39 and 29, the pressure of the high speed air jet stream R and pressure of the negative pressure air stream Q can be regulated and drying energy can be conserved.
By providing a barrier wall such as a flange or a bulging part in the circumferential part of the tips of the sucking-out nozzle 3c of the present invention or in the circumferential part of the tips of the sucking-out nozzle 3c and the blowing nozzle 3d in the components, air does not flow from the blowing nozzle 3d directly into the sucking-out nozzle 3c through a short cut and does not directly suck outer air OA. Rather, air goes deeply into fiber roots from the surface of the article to be dried such as a mat, carpet, etc. By using a high speed negative pressure air stream Q or by employing a multiplication effect of the high speed negative pressure air stream Q and the high speed air jet stream R (both streams being accelerated), water attached to the surface and gaps of fibers in the carpet, etc., can be quickly extracted and removed from the sucking-out nozzle 3c to provide continuous dehydrating and drying. Therefore, the consumption of water vaporization heat is largely decreased, temperature decrease of the article to be dried is prevented, rapid drying in low temperature is possible, increased heating energy is unnecessary contributing to energy saving, cost is decreased, drying is performed in an extremely short time making drying efficiency extremely high, there is no deterioration of the article to be dried by high temperature, there is no damage by friction, and there is no fear of producing wrinkles in the article to be dried. Additionally, along with water drop removal, foreign matters such as dust and especially ticks, lice, other injurious vermin and their eggs attached to the articles to be dried can be completely sucked and removed by the high speed negative pressure air stream Q. Thus cleaning and germfree effects are achieved along with obtaining a clean and dry carpet.
Drying efficiency further increases when hot air of 40.degree.-65.degree. C., for example, is used as the high speed air jet stream R. For example, an implanted mat having a rubber liner of 1 m.times.1 m width and 10 mm thickness can be dehydrated and dried in approximately 1 minute (FIG. 46) using three sets of components having a sucking-out nozzle 3c and a blowing nozzle 3d, both having flanges at the circumferences of their tips.
Dehydrating and drying devices having only sucking-out nozzles 3c provided with flanges or combinations of both the sucking-out nozzles 3c with flanges and the blowing nozzle 3d with flanges can be selected depending on the type or the thickness of the article to be dried.
When both the sucking-out nozzles 3c with flanges and blowing nozzles 3d with flanges are used, dehydrating and drying in low temperature can be performed in an extremely short time due to the multiplication effect achieved by the high speed air jet stream R accelerating in the region of the high speed negative pressure air stream Q. When cloths which are hard to be dried, such as tightly woven fabrics, are dried, as shown in FIG. 29, it is preferable to raise the sucking force of the high speed negative pressure air stream Q (for example to -1500 mmAq) and to weaken the air jet stream in the preceding zone 30 since the article to be dried contains a large amount of water. In the second zone 40 and the third zone 50, however, the pressure of the high speed air jet stream R is raised (for example, to approximately +1300 mmAq-+1500 mmAq) and the high speed negative pressure air stream Q is weakened to perform efficient drying.
The foregoing is considered as illustrative only of the principles of the present invention. Since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and applications shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention and the appended claims and their equivalents.
For example, the present invention has been explained using drying of an article which is wet with water as an example. When liquids other than water such as trichloroethylene or other organic solvents or mixtures of a liquid and water are used for washing, and the articles are to be dried, the water drop separating vessel mentioned above can be used as a solvent or other liquid drop separating vessel, and a solvent vapor adsorbing/removing device can be used in place of or in addition to a dehumidifier to concentrate and recover the solvent or to use it as a fuel. This results in a device being used as a rapid drying device in low temperature in a similar way as with water removal.

Number	Date	Country	Kind
6-126742	Apr 1994	JPX
6-222403	Dec 1994	JPX

Number	Name	Date
4231164	Barbee	Nov 1980
4592719	Bellehache et al.	Jun 1986
4690539	Radulski et al.	Sep 1987
5090132	Kobayashi et al.	Feb 1992
5117564	Taguchi et al.	Jun 1992
5205051	Hurwitt	Apr 1993
5377425	Kawakami et al.	Jan 1995

Rapid dehydrating and drying method and device usable in low temperature

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