JP5210715B2 - Dehydration method for squeezing dehydrator - Google Patents

Description

  The present invention relates to a dehydrating method for a squeeze-type dehydrator that removes moisture by pressing a laundry containing moisture such as sheets and towels after washing with a pressurizing body that moves up and down with hydraulic pressure. Especially when dewatering high-quality linen such as delicate and easy-to-break sheets, there is no quality problem such as tearing or pinhole generation, and the dehydration method has excellent productivity such as dehydration process time and dehydration rate. About.

Large quantities of linen used in hotels, restaurants, hospitals, etc. are washed in specialized factories, finished and packed through dehydration and drying processes, and delivered to the user's permission again.
The press-type dehydrator is excellent in both processing amount per one time, residual water rate and processing time, and has long played an important role in factories that wash and recycle large amounts of linen.
Recently, along with the increase in linen of such linens, fine linens such as delicate and easy-to-break sheets have no problem in terms of quality, but in terms of productivity such as dehydration process time and residual water rate, they reach the compression type dehydrator. It is regarded as a problem to process with no centrifugal dehydrator.
Therefore, even in the case of high-quality linens such as sheets that are delicate and easily torn, there has been a demand for the development of a dehydration method for a compression-type dehydrator that does not cause quality problems and does not significantly reduce productivity.

Various known techniques relating to the dehydration method of the compression dehydrator are known. Patent Document 1 that proposed low-pressure pressurization and high pressure as a method for improving the residual water ratio without damaging the quality of linen. An outline of Patent Documents 2 and 3 that propose a method of temporarily raising a press disk before pressurization will be described.
In Patent Document 1, when laundry containing a large amount of air or water mixed in a washing process is subjected to high-pressure pressurization without undergoing a sufficient preliminary dehydration process, the air or water in the laundry is rapidly increased. Proposed to have a preliminary dehydration process in which the dewatering pressure received by the laundry is maintained at a low pressure for a certain period of time after the start of dehydration, because there is a drawback that the laundry is damaged by being pressurized. Yes.

In Patent Document 2, conventionally, in order to pressurize and dehydrate laundry, pressurization is performed until the maximum dehydration pressure is reached over a certain period of time, for example, 90 seconds, but the laundry often breaks. In the surface layer of the laundry that comes into contact with the membrane (pressurized body), the laundry is pressed by the membrane so as to bridge between the multiple protrusions that exist in the manner of the overlap of the dehydrated laundry. It is presumed that it will be pulled without slipping.
As a measure for preventing the pulling (tearing) and tearing, the laundry (pressurized body) is once separated from the laundry after the laundry is depressurized to a low pressure, and the pulled laundry layer is freely relaxed. Then, it is proposed to pressurize again at high pressure.

Patent Document 3 is a rubber mat whose target is neither air-permeable nor water-permeable, up to a pressure at which the laundry is closed in a bag shape in the initial stage of dehydration or below the pressure at which the laundry is ruptured due to the accumulation of air. A technique is disclosed in which, after squeezing, the pressure is released and the squeezing membrane is temporarily raised and then pressurized to the maximum pressure.
JP 62-66898 A (FIG. 2) JP-A-4-15093 (FIG. 1) Japanese Patent No. 2680682 (FIG. 2)

The press dewatering technique disclosed in the above patent document is adjusted according to the type of dehydrator and the nature of the laundry material, and is effectively used for ordinary hotel linen, hospital linen, table linen and the like.
However, with regard to dewatering of delicate and easily broken high-grade linen that has recently appeared on the market, there is a further difference in material strength and water permeability, and it is necessary to invent a pressure dewatering method that does not cause any quality damage at all. there were. The problem for that will be described below.
(1) It is necessary to prevent pinholes generated in the early stage of pressing and dewatering.
This pinhole was supposed to be generated by applying high pressure to a laundry containing a large amount of air or water mixed in the washing process without going through a sufficient preliminary pressing process. In high-quality linens with low water permeability, the pressurization of a laundry containing a large amount of water and air at a low pressure itself generates a pinhole. Conditions must be found so that pressure can be applied without generating pinholes even at low pressures.

(2) It is necessary to eliminate the convex portion on the surface layer of the laundry and to bring it as close to the horizontal plane as possible.
That is, if the problem of removing the excess water in the laundry of (1) without difficulty is solved, if the pressurizing body comes into contact with the laundry at a low pressure, the surface layer portion has a plurality of convex portions. Then, the pressurizing body presses the place and applies a pulling force to the linen that bridges, causing tearing.
In addition, when the laundry is thrown into the basket with a large amount of water and the upper surface is inclined, the mixed air easily accumulates in a part of the laundry forming the high portion of the inclined surface. Since the force applied from the pressurizing body is concentrated on the pinhole, pinholes and tearing due to escape of air having a relatively high pressure occur, and it is necessary to solve these problems.

(3) After solving the problems (1) and (2) above, when the laundry is squeezed at a low pressure, the air remaining in the laundry is gradually pulled out, and a pinhole is formed in the internal linen. It is necessary to create conditions that do not occur.
In addition, before entering the next high-pressure pressing process, it is necessary to eliminate the tension of all the linen that bridges the convex part of the laundry surface layer part, and to prevent tearing, but about this problem Conventional techniques (for example, Patent Documents 2 and 3) are good references for solving means.
(4) Following the problem (3), the press disk is subjected to high pressure squeezing and dehydration by applying a high pressure. Depending on how the hydraulic pressure is increased, pinholes and tears may occur in the laundry surface layer. Because there is, it is necessary to review the pressure increase mode.

In order to solve the above problems, the present invention solves the problems by the following means.
(1) The dehydrating method of the squeeze type dehydrator as the first means is to put the laundry into a dehydration basket, and attach the laundry to the tip of the piston rod of the hydraulic cylinder, and the disc In a press-type dehydrator that squeezes with a pressurizing body in which a liquid is sealed in an intimate membrane, the laundry is received in a dehydration basket, the pressurizing body is moved up and down, and the press disk and piston rod attached with the pressurizing body and the pressure to reduce the weight of the movable part set such as a piston weighs less than the weight applied to the piston, the preliminary squeezing step to squeeze gently divided into the laundry at least 2 times, the preliminary squeezing step Next, gradually increase the hydraulic pressure, take a time corresponding to the strength of the laundry to reach a predetermined low hydraulic pressure, and after reaching the predetermined low hydraulic pressure, lift the press disk temporarily. It is allowed, characterized in that into the high-pressure compression after performing a low-pressure pressing and at the press disks one increasing step to mitigate mutual pulling of the pressing body laundry.

(2) The dehydrating method of the squeezing type dehydrator of the second means is the dehydrating method of the squeezing type dehydrator of the first means, wherein the press disk temporarily raised is followed by the low pressure squeezing and press disk temporary raising process. After the lowering and pressing the laundry at a low pressure, a high pressure pressing process is performed in which the hydraulic pressure is gradually increased to execute the high pressure pressing.

(3) The dehydrating method of the squeeze type dehydrator of the third means is to put the laundry into a dehydration basket, and attach the laundry to the tip of the piston rod of the hydraulic cylinder, and the disc In a squeezing dehydrator that squeezes with a pressurizing body that encloses a liquid in an intimate membrane, delicate and easily torn laundry is received in the dehydration basket and left for the required time, and excessively contained within the laundry. A dehydration delay start step for causing water to flow out from a water flow hole provided in the basket by a water head difference, and a press disc on which the pressurizer is attached after raising and lowering the pressurizer after the dehydration delay start step, pre the pressure to reduce the weight of the movable part set of the piston rod and the piston or the like the weight of less than the weight applied to the piston, squeezing lightly divided into the laundry at least twice Next to the pressing step and the preliminary pressing step, the hydraulic pressure is gradually increased from the preliminary pressing state of the press disk, and the time corresponding to the strength of the laundry is taken to reach a predetermined low hydraulic pressure, Further, after reaching a predetermined low hydraulic pressure, the press disk is temporarily raised to reduce the tension between the pressurizing body and the laundry, and the low pressure squeezing and press disk temporary raising process, Next, the press disk that has been temporarily raised is lowered, and the laundry is squeezed at a low pressure, and then a high pressure squeezing process is performed in which the hydraulic pressure is gradually increased to perform high pressure squeezing.

  According to the dewatering method of the compression dehydrator of the present invention (Claim 3), high-quality linen laundry such as sheets that are delicate and easily torn is processed with excellent productivity without causing quality problems. According to claims 1 and 2, it is possible to improve the yield of processed products without significantly impairing the productivity of general linens such as hotel linens and hospital linens. There is an effect to become.

Embodiments of the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. Drawing 1 is a side sectional view showing the situation before pressing of the press type dehydrator which can apply the present invention. FIG. 2 is a diagram called a dewatering pattern in which the pressing dewatering method of the present invention is represented by the relationship between the press disk displacement and dewatering pressure and the processing time of one step. 3 (a) and 3 (b) are side cross-sectional views showing the state of change of the laundry occurring in the dehydration basket during the dehydration delay start process. FIG. 4 is a side cross-sectional view illustrating a state in which the upper surface of the laundry in the dewatering basket is leveled during the pre-pressing process of the press disk.
FIG. 5 is a side cross-sectional view showing a schematic deformation state of the laundry and the pressurizing body in the dewatering basket in the low-pressure squeezing and press disk temporary raising process. FIG. 6 is a side cross-sectional view showing a schematic situation of the laundry and the pressurizing body in the dewatering basket when performing the high-pressure pressing process.

In the squeezing type dehydrator shown in FIG. 1, reference numeral 35 denotes a lower frame, which is installed on the floor surface. Reference numeral 36 denotes an upper frame, which is fixed to the lower frame 35 with a plurality of pillars 37 disposed thereon. 38 is a deck as a lattice member fixed to the lower frame 35, 39 is a deck plate which is a porous plate fixed to the deck 38, 40 is a porous mesh or mesh-like wide mesh belt for transporting water. Reference numeral 41 denotes a roll for driving the mesh belt 40.
Further, 42 is a dewatering basket whose lower half is formed in a cylindrical shape with a perforated plate and has a drainage property. 43 is a dehydration basket that is raised and lowered by an elevating device (not shown), and 43 is an opening formed in the upper portion of the dehydration basket 42. An insertion port 44 is a guide fixed to the dehydration basket 42 and engages with the pillar 37, 47 is a hydraulic cylinder fixed to the upper frame 36, 48 is a hydraulic device including an oil tank for the hydraulic cylinder 47 and a hydraulic circuit, 49 Is a hydraulic pump for the hydraulic device 48, 50 is a drive motor for the pump 49, and 51 is a piston rod for the hydraulic cylinder 47.

A press disk 52 is fixed to the piston rod 51. 53 is a pressurizing body which is an elastic film in which the press disk 52 and the opening are in close contact with each other and encloses water, 54 is a water supply port mounted on the press disk 52, 55 is an air vent port mounted on the press disk 52, Reference numeral 56 denotes a liquid such as water sealed between the press disk 52 and the pressurizing body 53.
Further, 58 is a continuous water washer previously arranged in the dehydration process, 59 is a discharge conveyor that is arranged after the dehydration process and is connected to the dryer in the direction of arrow B, 60 is clothes to be dehydrated, or an assembly thereof. Is a laundry.

In the case of dewatering high-quality linens such as sheets that are delicate and easily torn as laundry, the dehydration pattern represented by the relationship between the displacement and dehydration pressure of the press disk in FIG. 2 and one processing cycle time, and FIGS. This will be described based on the situation change of the laundry in the illustrated dehydration basket.
(1) Dehydration delay start process Usually, the laundry 60 is processed by the continuous water washing machine 58 arranged in front, and then is put into the dehydration basket 42 from the charging port 43 together with a large amount of rinse water and mixed air. The dewatering basket 42 is accommodated in a non-uniform form. For example, as shown in FIG. 3A, the surface layer portion of the laundry 60 becomes an inclined surface, and the mixed bubbles float and gather to form a plurality of air pockets.
When the laundry 60 in such a state is immediately squeezed by the lowering of the press disk 52 and the pressurizing body 53, in high-grade linen that is swollen by water and has reduced air permeability, air with increased pressure escapes from the linen. In addition, the air pocket bursts (pinhole).

Accordingly, the lowering of the press disk is held for T1 [sec], and a large amount of water in the laundry 60 is discharged from the drain hole of the dewatering basket 42 and the deck plate 39 at the bottom of the basket 42 by its own head difference. The “dehydration delay start process” is executed. (Refer to the part of Fig. 2 where the lower left dewatering pressure is zero)
FIG. 3B shows a state of change of the laundry 60 generated in the dewatering basket 42 by waiting for pressing dehydration by the lowering of the press disk 52 and the pressurizing body 53 for T1 [sec]. There is a natural drainage of the rinsing water, so that the air pockets on the surface of the linen are naturally deflated and reduced, so that the bursting of the air pockets in the next “pre-pressing step” can be prevented.
This non-pressing dewatering is effective for draining excess water slowly and reliably due to the head differential based on gravity that works constantly, even at low water-permeable linen, and at the same time atrophy of the air pool due to negative pressure accompanying drainage Since there is almost no water and air pool released from the laundry before the low-pressure squeezing is started, the occurrence of pinholes due to forced permeation of water and air by squeezing is greatly prevented. . This step is preferably delayed until the floating water on the inner upper surface of the dewatering basket 42 is not visible.
However, the air pocket remaining in the linen is not solved by this process, and the upper surface of the laundry is inclined due to the bias and there are a plurality of irregularities. When the pressure dewatering by the lowering of the pressurizing body 53 is started, a high pressure is locally generated, causing further pinholes and tearing in the linen of the laundry surface layer.

(2) preliminary squeezing process therefore does not give the following "preliminary squeezing process" in hydraulic pressing the hydraulic cylinder 47, the weight of the movable part set such as a press disk 52 and pressure member 53 and the piston rod 51 and piston A "preliminary squeezing step" is performed in which the pressure to be reduced is applied to the piston, the press disk 52 is moved up and down at a weight less than the same weight, and the surface layer portion of the laundry 60 loaded in a biased manner is lightly squeezed at least twice. . (Refer to FIG. 2 that the press disk 52 is lowered and lowered again and the dewatering pressure is almost zero. The process time is T2-T1 [sec].)
FIG. 4 shows that the plurality of convex portions of the laundry surface layer portion have been leveled by the second pressing, and it can be seen that the seeds of tearing due to the tension of the bridging linen are lost.
Wherein the next dehydration delayed start step (1), the pressure to reduce the weight of the said pressure body 53 is lifting a press disk 52 fitted with a pressure body 53, movable portion set of such piston rod 51 and piston Is added to the piston, and the pre-squeezing step is performed in which the laundry 60 is lightly squeezed into several times (at least twice) with a weight less than the same weight.
The aim of this step is to roughly level the protruding portion on the upper surface of the laundry that is biased into the dewatering basket 42 by the pressing body 53 that descends lightly and rolling it down, and then pressurizing the second time. The linen tears that may occur during the next "low pressure squeezing and press disk temporary raising process" by pressing down the plurality of convex portions of the laundry surface layer by lowering the body 53 Is to get rid of.
It should be noted that this step is not limited to high-quality linen that is delicate and easily torn, as can be seen from the above-mentioned aim, and it is also obvious that it is effective when applied to general laundry. In addition, the effect can be expected as the number of times of squeezing increases, but considering the problem of productivity, preliminary squeezing by raising and lowering the pressurizing body 53 is necessary at least twice.
In the first squeezing, it has been confirmed that the pressurizing body 53 descending lightly collapses and rolls down the protruding portion of the upper surface of the laundry that is thrown into the dehydration basket 42 and is roughly leveled. .

(3) Low-pressure squeezing and press disk temporary raising step Next, the hydraulic pressure of the hydraulic cylinder 47 is gradually increased, and the press disk 52 is torn below the strength of the laundry 60 over the time corresponding to the strength of the laundry 60 over time. After reaching a predetermined low dehydration pressure PL [MPa] that can exert pressure, and after reaching a predetermined low dehydration pressure PL [MPa], the press disk 52 is temporarily raised, and the pressurizing body 53 and the laundry 60 are The “low-pressure squeezing and press disk temporary ascent process” is performed to alleviate the tension. (In FIG. 2, the dehydration pressure gradually increases from almost zero in the previous process and reaches the top pressure, and then becomes zero again. The process time is T3-T2 [sec].)
In this process, by gradually increasing the squeezing force, the air remaining in the laundry 60 is carefully extracted, and the conditions for generating pinholes in the laundry 60 during the high-pressure dehydration in the next process are set. Aim to remove.
Further, as shown in FIG. 5, by temporarily raising the press disk 52, the pressurizing body 53 is expanded and contracted, and tearing due to friction between the pressurizing body 53 and the laundry 60 is prevented.
The “low-pressure pressing and press disk temporary raising step” is to gradually increase the hydraulic pressure from the preliminary pressing of the press disk 52 and to reach a predetermined low hydraulic pressure over a time corresponding to the strength of the laundry 60. Furthermore, after reaching a predetermined low hydraulic pressure, the press disk 52 is temporarily raised, and a low-pressure squeezing and a press disk 52 temporary raising process for relaxing the tension between the pressurizing body 53 and the laundry 60 are performed. And
In this step, the tensile force of the fibers is reduced by the deformation of the plurality of convex portions of the laundry surface layer in contact with the pressurizing body 53, and the air or bubbles remaining in the laundry 60 are removed from the pressure of the laundry 60. The aim is to separate and extrude from the laundry 60 while keeping the pressure below the strength. In particular, in the wet laundry 60, since the fabric yarn is swollen, the texture is often clogged. Therefore, it is considered that air or bubbles increased in pressure by squeezing permeate and diffuse while spreading the texture. Therefore, it is important to set the air to be vented over time at an air pressure that does not cause pinholes or rupture. It is obvious that this step is also effective when applied to general laundry without being limited to high-quality linen that is delicate and easily torn as can be seen from the above-mentioned aim.

(4) High-pressure squeezing step The laundry 60 has been squeezed at a low dehydration pressure by the previous step and preliminarily dehydrated, but if it is subjected to high-pressure squeeze at a stretch in the final step, bubbles remaining inside the laundry 60, etc. Is often ruptured into high-pressure air, causing tearing and tearing of the laundry 60, so that a high dehydration pressure PH [MPa] is performed over a predetermined time determined by the type of the laundry 60. Execute.
The time required for this step is T5-T3 [sec] until the press disk 52 and the dehydration basket 42 rise one after another after dehydration and the laundry 60 is discharged from the dehydrator by the discharge conveyor 59. The high pressure dehydration pressure is PH [MPa].
This process is characterized in that after the press disk 52 that has been temporarily raised is lowered and the laundry 60 is squeezed at a low pressure, the liquid pressure is gradually increased to perform high-pressure squeezing.
The aim of this process is to prevent pinholes generated due to sudden pressure changes and torn due to friction between the pressurizing body 53 and the laundry 60. Of course, if the method of increasing the hydraulic pressure is adjusted and applied to general laundry, it is obvious that the linen quality and the productivity of the dehydration process are effective.

  As described above, the dehydration method of the present invention has been qualitatively described based on FIGS. 2 and 3 to 6 to be safe and effective against easily torn linen, but in particular, high-grade sheets such as delicate and easily torn sheets. When linen is treated with the squeeze-type dehydrator of the present invention (residual water rate: 40), when a conventional centrifugal dehydrator is used (residual water rate: 60 to 70%, dehydration cycle time: 180 sec). -50%, cycle time: 120 sec), which is far superior in productivity.

Since the dehydration cycle time and the residual water rate can both be indicators of the productivity of washing / drying facilities, the delicate and easily broken linen such as high-quality sheets can be processed by a press-type dehydrator. It is clear that this dehydration method will bring considerable benefits to specialized laundry factories.
In addition, even in the case of hospital linen and restaurant linen that have been dehydrated with a compression dehydrator, the conventional dehydration cycle time is slightly reduced by applying the dehydration method according to claims 1 and 2 of the present invention. Even if it extends, it can be expected that the yield of linen will be considerably improved, so that an improvement in productivity can be expected.

It is side surface sectional drawing which shows the condition before pressing of the pressing-type dehydrator which can apply this invention. It is a diagram called the dehydration pattern showing the compression dehydration method of this invention by the relationship of the displacement and dehydration pressure of a press disk, and the processing time of 1 process. It is side surface sectional drawing which showed the condition of the change of the laundry which has arisen in the dehydration basket in the dehydration delay start process. It is the side sectional view showing the situation where the upper surface of the laundry in the dehydration basket was leveled in the preliminary pressing process of the press disk. It is side surface sectional drawing which showed the general deformation | transformation condition of the laundry in a spin-drying | dehydration basket and a pressurization body in a low pressure pressing and a press disk temporary raising process. It is side surface sectional drawing which showed the general condition of the laundry in a dehydration basket at the time of performing the high pressure pressing process, and a pressurization body.

Explanation of symbols

42 ... dehydration basket,
47 ... Hydraulic cylinder,
51 ... Piston rod,
52 ... Press disk,
53 ... Pressurized body,
56 ... Liquid,
60 ... Laundry,
PL ... Low dehydration pressure,
PH ... High dehydration pressure

Claims (3)

A pressing type in which the laundry is put into a dehydration basket, and the laundry is pressed with a press disc attached to the tip of a piston rod of a hydraulic cylinder, and a pressurizing body in which a liquid is sealed in a membrane closely attached to the disc. In the dehydrator
(1) the laundry, to accept the dewatering basket, the raising and lowering of the pressure body, in addition press the disc fitted with a pressure body, the pressure to reduce the weight of the movable part set of the piston rod and the piston or the like to the piston A pre-squeezing step in which the laundry is lightly squeezed at least twice in weight less than the same weight;
(2) Next to the pre-squeezing step of (1) above, gradually increasing the fluid pressure, taking a time corresponding to the strength of the laundry to reach a prescribed low fluid pressure, and further a prescribed low fluid A press-type dehydrator characterized by entering a high-pressure squeezing after performing a low-pressure squeezing and a press-disk tempering step for temporarily raising the press disk after reaching pressure and relaxing the tension between the pressurizing body and the laundry. Dehydration method.   The dehydrating method of the press type dehydrator according to claim 1, wherein the press disk that has been temporarily raised is lowered and the laundry is squeezed at a low pressure after the low pressure pressing and the press disk temporary raising step, and then the hydraulic pressure is gradually increased. A dehydrating method for a pressing dehydrator, wherein a high pressure pressing step for performing high pressure pressing is performed. A pressing type in which the laundry is put into a dehydration basket, and the laundry is pressed with a press disc attached to the tip of a piston rod of a hydraulic cylinder, and a pressurizing body in which a liquid is sealed in a membrane closely attached to the disc. In the dehydrator
(1) A delicate and easily torn laundry is received in a dewatering basket, left for a required time, and excess water contained in the laundry is drained from a water passage hole provided in the basket by a water head difference. Delayed start process,
(2) The following dehydration delayed start step (1), the raising and lowering of the pressure body, the press disks fitted with a pressure body, the pressure to reduce the weight of the movable part set of the piston rod and the piston or the like A preliminary squeezing step in which the laundry is lightly squeezed at least twice in a weight less than the same weight in addition to the piston;
(3) Next to the pre-squeezing step of (2), the hydraulic pressure is gradually increased from the pre-squeezed state of the press disk, and a predetermined low hydraulic pressure is reached over a time corresponding to the strength of the laundry. In addition, the press disk is temporarily raised after reaching a predetermined low hydraulic pressure, and the low-pressure squeezing and press disk temporary raising process for relaxing the tension between the pressurizing body and the laundry,
(4) Next to the low pressure pressing and press disk temporary raising step of (3) above, the press disk that has been temporarily raised is lowered and the laundry is pressed at a low pressure, and then the liquid pressure is gradually increased to execute high pressure pressing. A dehydrating method for a press-type dehydrator characterized by performing a high-pressure pressing step.

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