JP3127345U - Filter for drying furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter material for a drying furnace which does not contaminate the inside of the drying furnace, has good heat resistance and handleability, has a practical pressure loss, and has improved skin irritation at the time of replacement, and the same. In addition to providing a filter for a drying furnace, the filter medium is prevented from falling off during use.
SOLUTION: A filter outer frame 2 in which a filter medium mounting frame side 2b is extended toward the center of one opening surface of an enclosing frame having both surfaces open, and one of the enclosing frames having both surfaces opened. A filter inner frame 3 having a filter medium mounting frame side 3b extending toward the center of the opening surface is fitted, and the filter medium mounting frame side 3b of the filter inner frame 3 and the filter medium mounting of the filter outer frame 2 are fitted. In the drying furnace filter in which the drying furnace filter medium 6 in which short glass fibers are bonded with an organic binder is accommodated between the filter frame 2 and / or the inner peripheral surface of the filter inner frame 3. A filter medium slip-off preventing stopper 9 extending in the thickness direction of the filter medium 6 is provided on at least one side.
[Selection] Figure 1

Description

  The present invention relates to a filter for a drying furnace used in a drying furnace for a painting line of an automobile or the like.

A drying furnace filter used in a drying furnace for a painting line of an automobile or the like is used to remove spear, soot, etc. generated from the drying furnace, and mainly contains a filter medium in a metal filter frame. .
As a filter medium used for such a filter for a drying furnace, a short fiber such as an aromatic polyamide is formed into a sheet shape, and a synthetic fiber nonwoven fabric filter material in which fibers are bonded together with a binder or the like, or a molten glass at a high speed winder The glass long fibers in a state where many layers of the molten glass fibers are overlapped are cut from the winder, and the overlapping glass fibers are developed in the fiber layer direction to form a mat. A long fiber filter medium was used. Synthetic fiber nonwoven filter media such as aromatic polyamide have relatively low heat resistance and are used at 240 ° C or lower, but glass long fiber filter media have heat resistance exceeding 400 ° C, so they can be used in a wide temperature range. Has been.

  The temperature of the drying furnace in which the painting line is operating is generally constant, and the drying furnace filter has been exposed to a constant temperature for several months. The filter medium for a drying furnace used in such a drying furnace needs to be periodically replaced at a frequency of about once every several months. However, the long glass fiber filter medium has a problem of skin irritation of the long glass fiber. That is, the fiber diameter of the long glass fiber is several tens of μm, and since it is a filamentous fiber, when replacing the filter medium, the long glass fiber is finely broken and adheres to the clothes and body of the operator, There was a problem that it was easy to touch the skin and accompanied with tingling pain when changing the filter medium. In order to avoid this problem, Patent Document 1 discloses a unit-type air filter in which a long glass fiber filter medium is accommodated in a paper filter frame and the entire filter frame can be discarded. Patent Document 2 discloses a non-combustible fabric in which the surface of long glass fibers is coated with a fluororesin so as to suppress fuzz and eliminate discomfort such as a tingling feeling on the skin.

  Recently, paints used in painting lines of automobiles and the like have become non-solvent, and water-soluble paints have been used. In order to dry the water-soluble paint, since the drying temperature of the drying furnace is as high as 240 to 350 ° C., a filter medium that can be used without causing a problem even at this temperature is required.

However, the conventional synthetic fiber non-woven filter medium comprises a filter medium using general-purpose synthetic fibers, has insufficient heat resistance, and is used as a filter medium for a filter for a drying furnace having a high drying temperature of 240 to 350 ° C. There was a problem that I could not.
For example, the heat-resistant temperature of aromatic polyamide fibers is as low as 240 ° C, and when exposed to temperatures exceeding 240 ° C for a long time, the shrinkage of the fibers increases and a gap is formed between the filter medium and the frame. Since it flows into a drying furnace via, there was a problem that the drying furnace might be contaminated. Furthermore, high heat-resistant synthetic fibers (PBO fiber, PBI fiber, etc.) are very expensive and have a problem of poor practicality.

  In addition, the conventional glass long fiber filter medium has high heat resistance and is used in a range exceeding 400 ° C., but it does not use a binder, and the filter medium is configured only by the overlap of the glass long fibers. There was a possibility that the long glass fibers scattered in the drying furnace contaminated the drying furnace. When using an inorganic binder with high heat resistance to prevent the long glass fibers from scattering, the inorganic binder tends to generate more dust, and the problem of contamination of the drying furnace can be solved. There wasn't.

Furthermore, the conventional glass long fiber filter medium still has a problem of skin irritation, and even when a unit-type air filter that can be disposed as disclosed in Patent Document 1 is used, the heat resistance is insufficient. Moreover, even when the glass fiber is coated with a fluororesin as disclosed in Patent Document 2, there still remains a problem that the tip of the broken fiber pierces the skin. In order to improve the skin irritation of such a long glass fiber filter medium, it is conceivable to configure the filter medium using long glass fibers having a thin fiber diameter, but in this case, the density of the filter medium becomes high, and the filter medium There arises a problem that the pressure loss becomes high before it becomes impractical.
Therefore, the applicant does not contaminate the inside of the drying furnace, has good heat resistance and handleability, has a practical pressure loss, and has improved skin irritation at the time of replacement and The purpose of the present invention is to provide a filter for a drying furnace using the same, and as disclosed in Patent Document 3, a frame for placing a filter medium toward the center of one opening surface of an enclosing frame having both surfaces open. A filter inner frame in which a filter medium mounting frame side is extended toward the center of one of the opening surfaces of the surrounding frame that is open on both sides is fitted to the filter outer frame in which the sides are extended, and the filter inner frame The filter for drying furnaces which accommodated the filter medium for drying furnace which combined the short glass fiber with the organic binder between the frame edge for filter medium mounting and the frame edge for filter medium mounting of the said filter outer frame was proposed.

Utility Model Registration No. 3067922 JP-A-8-144173 JP 2006-122856 A

  However, when using the drying furnace filter previously proposed by the applicant, when the drying temperature is 240 to 350 ° C., the binder that bonds the fibers when the filter is installed disappears, and the bonds between the fibers disappear. Therefore, it is difficult to maintain the shape stably only by entanglement of short glass fibers, and there is a problem that the filter medium slides down to the lower part of the filter frame due to the weight of the filter medium particularly when the filter is used standing.

  Therefore, the present invention does not contaminate the inside of the drying furnace, has good heat resistance and handleability, has a practical pressure loss, improves skin irritation at the time of replacement, and further uses a filter medium during use. An object of the present invention is to provide a filter for a drying furnace that can prevent sliding-off.

The filter for a drying furnace according to the present invention is made to solve the above-described problem. As described in claim 1, the filter medium is placed toward the center of one opening surface of the surrounding frame having both surfaces open. A filter inner frame with a filter medium mounting frame side extended toward the center of one of the opening surfaces of the surrounding frame with both sides open is fitted to the filter outer frame with the frame side extended, and the filter In a filter for a drying furnace containing a filter medium for a drying furnace in which glass short fibers are bonded with an organic binder between a frame side for mounting a filter medium on an inner frame and a frame side for mounting a filter medium on the outer frame of the filter, A filter medium slip-off preventing stopper extending in the thickness direction of the filter medium is provided on at least one side of the inner peripheral surface of the filter outer frame and / or the filter inner frame.
The drying furnace filter according to claim 2 is characterized in that, in the drying furnace filter according to claim 1, a tip of the filter material slip-off preventing stopper is a non-spiral projection.
The drying furnace filter according to claim 3 is the drying furnace filter according to claim 1 or 2, wherein the height of the stopper for preventing slipping of the filter medium is 80% or less of the thickness of the filter medium, and the linear shape at the tip. The width is 2 mm or more.
Moreover, the drying furnace filter according to claim 4 is the drying furnace filter according to any one of claims 1 to 3, wherein the filter medium has a thickness of 10 to 60 mm and a basis weight of 50 to 400 g / m ^2. It is characterized by.

According to the filter for a drying furnace according to claim 1 of the present invention,
a) Since the short glass fibers constituting the filter medium are joined by the organic binder, the form of the filter medium is stable and the handleability is good when the filter medium for the drying furnace is replaced.
b) Further, even when the effect of the organic binder as a binder is lost, the form is stably maintained by the entanglement of the short glass fibers and the synergistic effect of the stopper for preventing the filter medium slipping, and the filter medium slips. Can be prevented. Therefore, the filter medium accommodated in the filter frame does not heat shrink and no gap is formed between the filter medium and the filter frame, and unfiltered air flows into the drying furnace and contaminates the drying furnace. There is no.
c) Since an organic binder is used as the binder, it does not generate dust like an inorganic binder when used in a drying furnace, and the inside of the drying furnace is not contaminated by the binder.
d) Moreover, since it is a short glass fiber, the heat resistance requirement is satisfied.

The filter material for a drying furnace of the present invention is obtained by joining short glass fibers fiberized by a flame method, a centrifugal method or the like with an organic binder.
For example, when the short glass fibers are formed of glass having a C glass composition, the filter medium composed of the short glass fibers does not shrink at 240 to 350 ° C., which is the drying temperature of the drying furnace, even when used for a long time. A gap is generated between the filter medium and the filter frame, so that air that does not pass through the filter medium flows into the drying furnace and does not contaminate the drying furnace.
In addition, if glass short fiber is formed using E glass, S glass, high silicate glass, etc. whose softening point is higher than C glass, it is possible to improve use temperature further.

  As said organic binder, organic binders, such as a phenol resin, a silicone resin, an epoxy resin, an acrylic resin, a urethane resin, a polyvinyl alcohol resin, a polyimide resin, can be used.

  Further, it is preferable to use short glass fibers having an average fiber diameter of 0.5 to 10 μm, and it is more preferable to use short glass fibers having an average fiber diameter of 4 to 8 μm. When the average fiber diameter of the short glass fibers exceeds 8 μm, the skin irritation that touches the skin of the operator when the glass fibers are crushed worsens, and when the average fiber diameter exceeds 10 μm, the skin irritation becomes more irritating. There is a problem of getting worse. In addition, if the average fiber diameter is less than 0.5 μm, the density of the filter medium becomes too high and pressure loss becomes excessive, and if the average fiber diameter is less than 4 μm, the rigidity of the fiber itself is insufficient. However, when the bonding property is lost, there is a problem in that the pressure loss increases due to the sag in the filter medium due to the wind pressure (change in the thickness of the filter medium).

  When the variation coefficient of the average fiber diameter of the short glass fibers is 30% or more, since the fiber diameters of the short glass fibers constituting the filter medium vary, the filter medium is obtained from thin glass fibers having the same fiber diameter. Compared with the case where it comprises, a filter medium does not become high density, but can set the pressure loss of a filter medium to the value suitable for practical use. The coefficient of variation is obtained by dividing the standard deviation of the fiber diameter by the average fiber diameter.

The filter material slip prevention stopper is used to prevent the filter medium from slipping in the filter frame. By attaching the filter with the side with the stopper facing upward, the filter can be prevented from slipping. What is necessary is just to provide in at least one side of the inner peripheral surface of an outer frame or / and a filter inner frame. Since it is possible to eliminate a mistake in attaching the side where the stopper is erroneously attached at the time of attaching the filter, it is preferable to provide it on the four sides.
The filter material slip-off preventing stopper may be provided directly on the inner peripheral surface of the filter outer frame. For example, it is provided to fix the SUS metal mesh porous plate to the opening surfaces of the filter inner frame and the filter outer frame. You may make it fix to the holding plate by welding etc. and to provide.
Further, the filter material slip-off preventing stopper may be provided on the inner peripheral surface of a strength reinforcing stay provided on the opening surfaces of the filter inner frame and the filter outer frame.
In any case, it is preferable that the filter material slip-off preventing stoppers are arranged at intervals of 50 to 100 mm.
When the shape of the stopper for preventing slipping off of the filter medium is a spire-shaped protrusion, there is a risk that an operator may be injured when the filter medium is attached or replaced. Therefore, the tip is preferably a non-spiral protrusion. Considering the risk of injury, it is preferable to make the tip linear. In that case, the linear width of the tip is preferably 2 mm or more. Further, considering the piercing property to the filter medium, it is preferably 5 mm or less.
In addition, since the filter medium of the drying furnace filter has a relatively low density, if the tip is sharp and has a small cross-sectional shape such as a nail, the force to press the filter medium is weak. Are not sharp and the cross section is preferably elliptical or rectangular.
Further, if the stopper for slipping off the filter medium has a plate shape with an L-shaped cross section, the bottom part can secure a sufficient welding allowance, and if the rising part is trapezoidal, the piercing to the filter medium is excellent and the filter medium is at the bottom. It is most preferable that the rising portion is formed in a trapezoidal shape with a plate shape having an L-shaped cross section in order to catch drooping on the surface and prevent slipping. However, the rising portion may be rectangular without being limited thereto. Further, the upper part of the trapezoid may be rounded instead of the complete trapezoid.
The height of the filter material slip-off preventing stopper is preferably 80% or less of the filter material thickness. This is because if it exceeds 80%, there is a problem that a risk of leakage occurs through the filter medium.

In addition, if the filter medium has a thickness of 10 mm or more and a basis weight of 50 g / m ² or more, a filter medium having sufficient filter retention, dust retention capacity such as dust and soot can be obtained, and a stopper for preventing the filter medium from slipping off There is no leakage through the filter media. In addition, if the thickness is 60 mm or less and the basis weight is 400 g / m ² or less, it can be used as a filter medium with an appropriate pressure loss, and the filter medium slip prevention stopper is difficult to pierce and fix the filter medium and damage the filter medium. There is no problem of deformation. Therefore, the filter medium preferably has a thickness of 10 to 60 mm and a basis weight of 50 to 400 g / m ² . The filter medium need not be a single layer, and a plurality of layers may be bonded together.

Next, an embodiment of the filter for a drying furnace of the present invention using the filter medium will be described with reference to the drawings. FIG. 1 is a front view and a longitudinal sectional view showing a filter medium 6 and a filter inner frame 3 in a part of a filter for a drying furnace of the present invention, and FIG. 2 is a sectional view of FIG. 3 is an enlarged cross-sectional view of a main part of the A part and the B part, FIG. 3 is a perspective view of a stopper 9 for preventing slipping provided on the pressing plate 7, and FIG. 4 is a filter outer frame 2 and a filter inner frame before assembly. FIG.
As shown in FIGS. 1 to 4, the filter frame includes a filter outer frame 2 and a filter inner frame 3. The filter outer frame 2 is formed with an enclosing frame having both sides opened by four side plates 2a, and a filter medium mounting frame side 2b is extended toward the center of one of the opening surfaces of the enclosing frame. A perforated plate 4 is clamped around the circumference of the frame 2 for mounting 2b from the inside of the surrounding frame by a pressing plate 7 and fixed by welding.
As shown in FIG. 3, four stoppers 9 having a L-shaped cross section with an upper piece trapezoidal and a lower piece rectangular are welded and fixed to the pressing plate 7 per side.
Further, the filter inner frame 3 that can be fitted to the filter outer frame 2 is formed with a surrounding frame having both sides opened by four side plates 3a, and the filter medium is placed on one opening surface of the surrounding frame toward the center thereof. A frame side 3b for installation is extended, and a perforated plate 5 is clamped by a presser plate 7 from the inside of the surrounding frame to the frame side 3b for filter medium placement and fixed by welding.
Reinforcing stays 8 are provided on the respective opening surfaces of the filter outer frame 2 and the filter inner frame 3 so as to face each other in a cross shape, and also on the inner peripheral surface side of the reinforcing stay 8 of the filter outer frame 2. The plate-shaped slip-off prevention stopper 9 having a trapezoidal rising portion and a rectangular L-shaped cross section is welded and fixed at four locations.
The filter medium 6 is accommodated in the filter inner frame 3, the filter outer frame 2 is put on the filter inner frame 3, and the filter medium 6 is fixed with the slip-off preventing stopper 9. The filter medium 6 is hermetically fixed between the two and the filter 1 for the drying furnace is obtained.

The configuration of the filter frame that accommodates the filter medium 6 is not limited to that shown in FIG. 4 as long as the filter medium 6 can be accommodated and sealing performance is obtained.
Moreover, as a material of the filter outer frame 2 and the filter inner frame 3, metal things, such as aluminum, stainless steel, and a steel plate, can be used.

  Further, as the perforated plates 4 and 5 provided as the fiber scattering preventing material, a wire net, a lath net, a punching board, a glass fiber woven fabric, or the like can be used. The perforated plate 4 provided on the filter outer frame 2 on the air inflow side is not always necessary from the viewpoint of preventing the short glass fibers constituting the filter medium 6 from scattering into the furnace, but in the inflow side direction. By suppressing the scattering of the fibers, cleaning on the inflow side can be made unnecessary, and the porous plate 4 itself captures coarse particles, so that the life of the filter medium 6 can be extended.

  Further, as a fiber scattering prevention material, the perforated plate 5 provided in the filter inner frame 3 on the air outflow side has the peeled glass short fibers in the drying furnace even when a small amount of short glass fibers are peeled off from the filter medium 6. To prevent outflow. The fiber scattering prevention material is desirably a perforated plate of 5 to 200 mesh, more preferably 10 to 60 mesh. This is because if it is less than 10 mesh, the effect of preventing fiber scattering is small, and if it is less than 5 mesh, the effect of preventing fiber scattering is poor. Further, if it exceeds 60 mesh, the pressure loss of the perforated plate 5 itself cannot be ignored and is not preferable. If it exceeds 200 mesh, the pressure loss of the perforated plate 5 itself becomes very high and difficult to use.

Hereinafter, specific examples of the present invention will be described under comparison with comparative examples.
(Example)
A water-soluble phenol resin binder (“Showonol” (registered trademark) manufactured by Showa Polymer Co., Ltd.) is bonded to a short C glass fiber in which fibers are entangled in wool with an average fiber diameter of 6 μm and a fiber diameter variation coefficient of 60%. ))) Was attached by spraying to 9% by mass to prepare a filter medium having a thickness of 25 mm and a basis weight of 175 g / m ² .
The filter medium is housed in a SUS filter inner frame in which a 12-mesh SUS wire mesh is fixed with a holding plate as a porous plate, and a 12-mesh SUS wire mesh is fixed with a holding plate as a porous plate, with a thickness of 0.5 mm and an upper side of 2 mm. 4 pieces of a stopper for preventing slip-off having an L-shaped cross section consisting of a trapezoidal rising portion having a lower side of 8 mm and a height of 15 mm and a rectangular bottom portion having a thickness of 0.5 mm and a thickness of 8 mm × 13 mm are welded per side of the pressing plate. A filter for a drying furnace was obtained by placing a fixed SUS filter outer frame on the filter inner frame.

(Comparative example)
A filter for a drying furnace was obtained in the same manner as in Example 1 except that a stopper for preventing slipping was used having a diameter of 1.5 mm, a height of 20 mm, and a cedar-shaped tip.

  In both examples and comparative examples, the vertical and horizontal dimensions of the drying furnace filter were set to 500 mm × 500 mm.

Next, about each drying furnace filter of an Example and a comparative example, comprehensive evaluation of the handling property at the time of replacement | exchange operation | movement and the filter medium form stability at the time of use of each said drying furnace filter was performed.
The handling property at the time of the replacement work was evaluated as to whether or not there is a risk that the filter material slip-off preventing stopper is touched with a bare hand and the hand is cut or stuck in the finger.

  The filter media form stability when using the filter for the drying furnace is such that after passing 300 ° C air through the filter for the drying furnace for 24 hours and after the binder of the filter medium has disappeared, the filter medium is left for 1 hour and the filter medium does not slide down. It was evaluated by whether or not

The filter for the drying furnace of the example has no skin irritation at the time of replacement of the filter medium, and there is no risk of injury to the operator by the stopper for preventing the filter medium from slipping. It was excellent in filter media form stability, good heat resistance at 300 ° C., less scattered fibers after ventilation at 300 ° C., and the problems of conventional filter media were improved.
However, the filter for the drying furnace of the comparative example has no skin irritation at the time of replacing the filter medium, has good heat resistance at 300 ° C., has less fiber scattering after ventilation at 300 ° C., and has problems with conventional filter media. Although improved, the tip of the filter media slip prevention stopper has a spire-like protrusion, which may cause injury to the operator, resulting in poor handling and the relatively low density of the filter media. Since the tip of the stopper is a spire-like protrusion, the force of passing through the filter medium and pressing the filter medium is weak, so the filter medium slipped by about 10 mm, and the filter medium form stability was poor.

(A) Front view, (b) Longitudinal sectional view of the drying furnace filter of the present invention FIG. 1A is an enlarged cross-sectional view of the main part of the A part, and FIG. 1B is an enlarged cross-sectional view of the main part of the B part. A perspective view of a stopper for preventing slipping provided on the holding plate The perspective view of the filter inner frame and filter outer frame of the filter for drying furnaces of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Filter for drying furnaces 2 Filter outer frame 2a Side plate 2b Frame edge for filter medium placement 3 Filter inner frame 3a Side plate 3b Frame edge for filter medium placement 4 Perforated plate (inflow side)
5 perforated plate (outflow side)
6 Filter media 7 Holding plate 8 Reinforcement stay 9 Stopper for preventing slipping

Claims (4)

  To the center of one of the opening surfaces of the surrounding frame that is open on both sides, toward the center of one opening surface of the surrounding frame that is open on both sides, toward the center of one of the opening surfaces A filter inner frame extending from the filter medium mounting frame side is fitted, and an organic binder is used between the filter medium mounting frame side of the filter inner frame and the filter medium mounting frame side of the filter outer frame. In a filter for a drying furnace containing a filter medium for a drying furnace combined with short glass fibers, for preventing the filter medium from slipping off at least one side of the filter outer frame and / or the inner peripheral surface of the filter inner frame in the thickness direction of the filter medium A filter for a drying furnace, which is provided with a stopper.   The filter for a drying furnace according to claim 1, wherein the tip of the stopper for preventing slipping of the filter medium is a non-spiral projection.   The filter for a drying furnace according to claim 1 or 2, wherein the height of the stopper for preventing slipping of the filter medium is 80% or less of the thickness of the filter medium, and the linear width of the tip is 2 mm or more. 4. The drying furnace filter according to claim 1, wherein the filter medium has a thickness of 10 to 60 mm and a basis weight of 50 to 400 g / m ² .

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