JP6808562B2 - Spacer for pleated type filter - Google Patents

Description

The present invention relates to a spacer attached between the pleats of a filter having a filter medium molded by pleating.

In order to remove dust and mist in gas and solids and liquids floating in liquid, a filter in which a filter material is fixed in a frame is used.
For such a filter, the increase in pressure loss caused by the passage of fluid is suppressed by increasing the filtration area of the filter material, and the amount of dust and the like captured by the filter material is increased to replace the filter. In order to extend the life and the like, a filter medium is often formed into a pleated shape or a corrugated shape to increase the area of the filter medium (for example, Patent Document 1 and Patent Document 2).

Here, when the filter medium is made into a pleated shape, the flow resistance of the fluid passing through the filter medium causes the folds of the continuous pleats and the flat portion between the folds to bulge toward the outflow side, and the continuous pleats are formed. A phenomenon occurs in which the fluid adheres to each other and hinders the flow of the fluid, reducing the area of the filter medium effectively used for filtration.

In order to prevent the occurrence of this phenomenon, in Patent Document 2, a linear resin solid such as a hot melt resin is applied between the folds to maintain the distance between the folds, and in Patent Document 3, pleats are used. A space-holding member is arranged on the inlet side in order to hold the space between the two. Further, in Patent Document 4, the net material is pleated together with the filter medium to maintain the fluid flow even when the pleats approach each other, and in Patent Document 5, the reinforcing material is pleated together with the electlet non-woven fabric and the glass fiber filter material. , The filter medium is reinforced against the flow of fluid and the accumulation of collected objects.

JP-A-2002-233711 Japanese Unexamined Patent Publication No. 2007-083178 Japanese Unexamined Patent Publication No. 2014-061467 Special Table 2006-501058 Japanese Unexamined Patent Publication No. 2012-0863183 Japanese Unexamined Patent Publication No. 2010-11760

However, the resin solid matter used in Patent Document 2 is one in which a linear hot melt resin or the like is coated between the pleated portions, and the pressure between the resin solid matter is caused by the pressure of the fluid passing through the entire surface of the filter medium. It is not possible to prevent the adhesion of the pleated plastic that extends to the surface.

Further, since the interval holding member used in Patent Document 3 is attached only to the upper and lower ends of the inflow side of the filter material and is held only on the inflow side, it is necessary to prevent the pleats from sticking to each other due to the pressure of the fluid. Can't.

Further, the mesh-like reinforcing material used in Patent Document 4 and Patent Document 5 is pleated together with a filtering material mainly for the purpose of removing dust and mist (hereinafter referred to as "main filtering material"). Since the mesh material or the like spreads over the entire surface of the filter material, the fluid does not flow to the fibers or the like constituting the mesh material or the like. This directly leads to a decrease in the effective filtration area of the filter medium and an increase in pressure loss.

In addition to these problems, when the flow rate and supply pressure of the fluid pulsate frequently, the mesh etc. also oscillates according to the amplitude of the main filter material, and the mesh etc. is a thick fiber for high strength. If the material has a diameter or is made of a highly rigid material, there arises a problem that the mesh or the like breaks due to fatigue fracture due to the pulsation.

In the present specification, the resin solid matter described in Patent Document 2, the spacing member described in Patent Document 3, the support layer described in Patent Document 4 and Patent Document 5, the non-woven fabric filter medium for reinforcement, and the like are pleats. The parts used to maintain the distance between the fabrics are hereinafter referred to as spacers.

In addition, a filter medium having a function of removing and trapping dust and mist to be collected contained in a fluid and pleated is called a main filter medium, and is pleated together with the main filter medium and is mainly used. The filter material that assists the removal / capture function of the filter material is called a sub-filter material.

The present invention has been made to solve the above-mentioned problems, and is a spacer used for a pleated type filter that allows fluid to flow from one side surface to the other side surface, and is between pleated portions on the other side surface side of the pleated fabric. A valley portion that is attached and is not continuous with other spacers attached between other adjacent pleated portions and is arranged at a position facing the other side surface side of the inflow side folded portion of the pleated fabric, and the pleated antiverse. It has a ridge portion arranged at a position close to the fold-back portion on the outflow side, the number of the ridges is at least twice the number of the valleys, and the length in the direction along the fold of the pleated fabric. Is a spacer having substantially the same length in the direction along the folds forming the peak portion and the valley portion of the spacer.

Further, the present invention is a spacer used for a cylindrically molded pleated type filter that allows fluid to flow from the inner peripheral side to the outer peripheral side, and is attached between each pleated portion on the outer peripheral side of the cylindrically molded pleated fabric. The valley portion is arranged at a position facing the folded portion on the inner peripheral side of the pleated fabric, which is not continuous with other spacers attached between the other adjacent pleated portions, and the outer peripheral side of the pleated fabric. It has a mountain portion arranged at a position close to the folded portion, the number of the mountain portions is more than twice the number of the valley portions, and the length in the direction along the fold of the pleated fabric is the said. It is a spacer having substantially the same length in the direction along the folds forming the peak portion and the valley portion of the spacer.

Since the spacers are not continuous and the area covering the main filter material that mainly captures dust and mist is small, the spacer does not interfere with the flow of fluid, and the effective filtration area of the main filter material can be secured.

Further, since the spacer does not exist in the pleated folded portion on the outflow side where the amplitude of the filter medium due to the pulsation of the fluid is larger than that on the inflow side of the fluid, there is no possibility of breakage due to fatigue failure of the spacer.

Further, since the spacer has valleys and more than twice as many peaks as the valleys and can exhibit elasticity by the peaks and valleys, the main filter medium is caused by the pulsation of the fluid. Even if swelling or contraction occurs, the spacer can regulate and absorb the movement. Therefore, it is possible to keep the pleated spacing of the main filter material constant and prevent a decrease in the effective filtration area due to the close contact of the pleated portions.

As the spacer according to the present invention, it is desirable to use a mesh material made of a woven fabric of thermoplastic synthetic resin fibers having an aperture ratio of 30% or more and 70% or less as the spacer material.
A mesh material made of a thermoplastic synthetic resin fiber having appropriate strength and elongation can be used in order to maintain the opening of the spacer and to maintain the elasticity required for the spacer.

As the spacer according to the present invention, it is desirable to use a mesh material made of an extruded net of a thermoplastic synthetic resin having an aperture ratio of 30% or more and 70% or less as the spacer material.
An extruded net is used to maintain the opening of the spacer, to use a thermoplastic synthetic resin having appropriate strength and elongation to maintain the elasticity required for the spacer, and to prevent breakage from the cut end of the spacer. Can be used.

As the spacer according to the present invention, it is desirable to use a mesh material made of a thermoplastic synthetic fiber cut out by heat cutting or ultrasonic cutting or an extruded net made of a thermoplastic synthetic resin.
By using this cutting method, it is possible to prevent the spacer from breaking from the cut end, and the cut end damages the main filter medium and the sub-filter material as compared with the cold cut in which the cut surface has a sharp shape. Possibility decreases. In particular, when the main filter medium oscillates due to fluid flow rate, pressure fluctuation, etc., the cut end of the spacer and the main filter medium and / or the secondary filter medium frequently repeat contact and detachment or pressing and releasing, so that the cut end It is desirable to use a mesh material made of thermoplastic synthetic fibers cut out by heat cutting or ultrasonic cutting or an extruded net made of thermoplastic synthetic resin in order to prevent breakage and damage to the main filter medium and the secondary filter medium.

The spacer according to the present invention may also have an intermediate valley portion that is an intermediate portion of the pleated portion of the pleated fabric and is folded back from the inflow side to the outflow side. Further, the spacer according to the present invention may have an intermediate valley portion that is folded back from the inner peripheral side toward the outer peripheral side at the intermediate portion of the pleated portion of the pleated fabric.

The spacer according to the present invention can be suitably used as an oil mist separator for removing oil mist in the air discharged from an air compressor whose flow rate and / or pressure fluctuates frequently.

By using the spacer of the present invention, it is possible to prevent the deformation of the main filter material and the sub-filter material caused by the flow resistance of the fluid while preventing the increase in the pressure loss caused by the decrease in the effective filtration area. Further, even when pulsation occurs in the fluid supply, fatigue fracture that occurs in the spacer, the main filter material, the sub-filter material, and the like can be prevented.

It is a figure which shows the appearance of the filter which concerns on 1st Embodiment of this invention. FIG. 1 is an enlarged view of a part of the AA cross section of the filter according to FIG. It is a figure which shows the appearance of the filter which concerns on the 2nd Embodiment of this invention. It is a figure which shows the BB cross section of the filter which concerns on FIG. It is an enlarged view of a part of FIG. It is a figure which shows the form of the spacer which concerns on this invention. It is a perspective view of the spacer which concerns on FIG. 6B. It is sectional drawing which inserted the spacer of FIG. 6A between the pleats of a filter. 6 is a cross-sectional view in which the spacer of FIG. 6B is inserted between the pleats of the filter. It is sectional drawing of the conventional pleated type filter which does not use a spacer. It is a pressure loss measurement result of the filter concerning an Example and a comparative example.

The spacer of the present invention is obtained by pleating a woven fabric composed of warp and weft of thermoplastic synthetic fibers, a mesh material composed of an extruded net of thermoplastic synthetic resin, or the like by a known pleating method. A cut piece of pleated cloth is used. The pleating method includes, for example, the one described in Patent Document 6, and the woven fabric is a monofilament woven fabric or a multifilament woven fabric sold by Nippon Special Woven Fabric Co., Ltd., NBC Mesh Tech Co., Ltd., etc., and the extrusion molding net is three. There are NALTEX (registered trademark) and DELNET (registered trademark) sold by Akira Co., Ltd., and Trical Net (registered trademark) sold by Takiron Co., Ltd.

It is preferable that these mesh materials use an aperture ratio of 30% or more and 70% or less. This is to maintain the opening of the spacer and to maintain appropriate strength and elongation in order to maintain the elasticity required for the spacer.

When a woven fabric is used as the spacer, a woven fabric made of filament yarn having a fiber diameter of 100 μm or more and 1000 μm or less, or a thermoplastic synthetic fiber made of multifilament yarn having a total fiber amount equivalent to the fiber diameter can be used. The fiber diameter should be 100 μm or more to maintain the elasticity and strength required for the spacer, and 1000 μm or less to make the thickness when the spacer is inserted between the spacer openings and pleats appropriate. Is preferable.

When an extruded net is used as the spacer, it is preferable to use a thermoplastic synthetic resin having a fibrous portion having a thickness of 100 μm or more and 1000 μm or less, which constitutes an opening (mesh). The thickness of the fibrous part should be 100 μm or more to maintain the elasticity and strength required for the spacer, and 1000 μm or less to make the thickness when the spacer is inserted between the spacer openings and pleats. Can be used.

As the thermoplastic synthetic fiber and the thermoplastic synthetic resin, polypropylene, polyethylene terephthalate, polyamide fiber, polytetrafluoroethylene, polyvinylidene fluoride, polyphenylene sulfide, etc. are used as the elasticity, durability, and chemical resistance required for the properties of the fluid and the spacer. It can be selected based on the required performance such as sex.

As a method of cutting these mesh materials after pleating, heat cutting or ultrasonic cutting is preferable. By cutting by heat cutting or ultrasonic cutting, it is possible to prevent the spacer from breaking from the cut end, and it is possible to prevent the spacer from being decomposed even when the main filter medium or the like violently repeats the amplitude due to the pulsation of the fluid. it can. Further, when heat cut or ultrasonic cut is used as compared with cold cut in which the cut surface has a sharp shape, a resin ball is formed by fusing in the cut portion, so that the cut end of the spacer is the main filter medium. -The possibility of damaging the secondary filter medium is reduced. In particular, when the main filter medium repeats amplitude due to fluid flow rate, pressure fluctuation, etc., the cut end of the spacer and the main filter medium and / or the secondary filter medium frequently repeat contact and detachment or pressing and releasing, so that the cut end It is preferable to use a heat cut or an ultrasonic cut that forms a resin ball at the cut end in order to prevent the breakage and damage of the main filter medium and the secondary filter medium.
However, if it is considered that the mesh material and composition, the strength of the main filter medium and / or the secondary filter medium, the frequency of amplitude, etc. are not considered, and the mesh does not break or the main filter medium and the secondary filter medium are not damaged, cold cut is performed. A known cutting method with high productivity can be used.

The first embodiment of the spacer according to the present invention will be described with reference to the drawings.
Figure 1 is a profile view of a flat filter 1 spacer according to the present invention is used, FIG. 2 is a plan view of a pleated section an enlarged portion of the A-A cross section of FIG.

In FIG. 2, the spacer 3 is independently inserted between the pleated portions 23 on the outflow side of the pleated anti-2, and the valley portion 32 of the spacer 3 is arranged so as to face the folded portion 21 on the inflow side of the pleated anti-2. Further, in the valley portion 32 of the spacer 3, the number of peak portions 31 is 2, whereas the number of valley portions 32 is 1. As a result, spacers are uniformly arranged in the space in the vicinity of the inflow side folded portion 21 where the distance between the pleats 23 is narrow and the vicinity of the outflow side folded portion 22 where the distance between the pleats is wide, and the pleated anti-expansion due to the flow resistance of the fluid. Can be regulated uniformly.

Further, the spacer 3 shown in FIG. 2 has an intermediate valley portion 33 that is folded back from the inflow side to the outflow side at the intermediate portion of the pleated anti-2. The number of pleats for the main filter material and sub-filter material depends on the size of the filter, the thickness of the entire filter material, the height of the pleats, the viscosity of the fluid to be filtered, the type of dust to be trapped, the mist, etc. The pleats interval is also different. Therefore, when the distance between the vicinity of the inflow side folded portion 21 and the vicinity of the outflow side folded portion 22 of the pleated anti-2 is significantly different, the number of the peaks 31 of the spacer 3 needs to be twice or more the number of the valleys 32. By forming the intermediate valley portion 33 to be folded back at the intermediate portion of the pleats, the shape of the spacer can be selected according to the interval of the pleats. Examples of such spacer shapes are shown in FIGS. 6 (a) to 6 (f) and FIG. 7. 6 (a) to 6 (f) are types of spacer shape examples, and FIG. 7 is a perspective view of FIG. 6 (b).

The spacer 3 of the present invention can be inserted into the space between the pleated portions 23 of the pleated anti-2 and adhered or welded to the end plate 5 together with the pleated anti2 to be fixed. At that time, in order to prevent the pleated anti 2 from excessively expanding and the spacer 3 from coming off to the outflow side due to the flow resistance of the fluid, the outer winding anti4 is attached to the outflow side or the outflow side and the inflow side of the filter 1. be able to. Further, instead of the outer winding roll 4, the outflow side of the filter 1 or the entire filter can be covered with a rigid outer cylinder or the like.

3 to 5 are views showing the spacer according to the present invention and the second embodiment of the filter using the spacer. In this embodiment, the filter 1 and the pleated fabric 2 used for the filter 1 have a cylindrical shape, the inner peripheral side of the cylinder is the fluid inflow side 6, and the outer peripheral side is the fluid outflow side 7. FIG. 3 is a view showing the appearance of the filter 10 using the spacer according to the present invention, FIG. 4 is a sectional view taken along line BB of FIG. 1, and FIG. 5 is an enlarged view of a part of FIG. And the parts having the same function as in FIG. 2 are numbered the same.

The present embodiment is different from the first embodiment in that the filter 10 is cylindrical, and the outer winding counter 4 and the end plate 5 are ring-shaped accordingly. This type of filter is used, for example, to remove oil mist in compressed air discharged from a refueling type air compressor, oil mist in exhaust gas discharged from an oil rotary vacuum pump, and the like. Therefore, the fluid is passed through with the inner peripheral side of the cylinder as the inflow side and the outer peripheral side as the outflow side, and the oil mist is collected and aggregated using the main filter medium and the auxiliary filter medium to discharge the fluid from the outflow side, and the main filtration is performed. The material / sub-filter material is collected and the agglomerated oil is discharged from the outflow side.

Spacers were prepared with the configurations shown in Table 1, and pleated type filters in which the spacer 3 was inserted between the pleats were prepared as shown in FIGS. 8 and 9. The pleated fabric ² is made of a glass fiber non-woven fabric having a fiber diameter of 1.3 μm and a basis weight of 350 g / m ^{2 and} a PET spa having a basis weight of 20 g / m ^2.

A pleated fabric sandwiched between non-woven fabrics is used to form a cylindrical pleated fabric, which is integrally formed with an inner cylinder 8, an outer cylinder 9, an outer filter medium 10, and an end plate 5 to have a pleated height of 20 mm and a pleated number of 45. I made a type filter. FIG. 10 is a conventional pleated type filter that does not use the spacer 3.

The present embodiment is different from the first embodiment in that the filter 1 is cylindrical, and the outer winding counter 4 and the end plate 5 are ring-shaped accordingly. This type of filter is used, for example, to remove oil mist in compressed air discharged from a refueling type air compressor, oil mist in exhaust gas discharged from an oil rotary vacuum pump, and the like. Therefore, the fluid is passed through with the inner peripheral side of the cylinder as the inflow side and the outer peripheral side as the outflow side, and the oil mist is collected and aggregated using the main filter medium and the auxiliary filter medium to discharge the fluid from the outflow side, and the main filtration is performed. The material / sub-filter material is collected and the agglomerated oil is discharged from the outflow side.

After each filter was used until it received 10,000 pulsations, the condition of the filter pleats and spacers was observed.
In the filters of Examples 1, 2 and 4, both the pleated fabric and the spacers were the same as those before use, but in the filter of Example 3, some breakage occurred at the ends of the two spacers out of 45.

Next, for the filters of Examples 2, 5 and 6 and Comparative Examples 1 to 3, the increase in pressure loss when the air flow rate was changed was measured (FIG. 11).
Compared with the filter of Example 2 using the spacer of the present invention, the pressure loss increase is higher in Comparative Example 3 in which the spacer is not used, and the effect of using the spacer of the present invention appears. Further, the spacer using a woven fabric having a fiber diameter of 100 μm or less (Comparative Example 1) has a higher pressure loss than the spacer using a woven fabric having a fiber diameter of 120 μm (Example 5), and further, the opening ratio is 30% or less. The spacer using a woven fabric (Comparative Example 2) had a significantly increased pressure loss as compared with the spacer using a woven fabric having an aperture ratio of 37% (Example 6). In Comparative Example 1, since the fiber strength is small, the elasticity required to maintain the pleated spacing cannot be generated, and in Comparative Example 2, since the aperture ratio of the spacer is small, the air passage area is reduced and the pressure loss is reduced. Is probable to have occurred.

Using the filter of Example 2, the period until the filter was damaged by the pulsation of the air introduced into the filter was measured. Further, the same measurement was performed on the conventional filter without a spacer shown in FIG.
As a result, in the filter of Example 2, fatigue fracture and the like did not occur in the pleated fabric even when pulsation was applied 200,000 times. However, in the filter of Comparative Example 3, fatigue fracture occurred at the outflow side folded portion of the pleated fabric due to about 60,000 pulsations, and air leakage began to occur.

The spacer according to the present invention is used to prevent deformation caused by the flow resistance of a pleated type filter, and can be particularly suitably used for a filter that filters a fluid in which a flow rate change or a pressure change occurs frequently. Further, the filter using the spacer according to the present invention is an oil mist separator that removes oil mist in compressed air discharged from a refueling type air compressor, oil mist in exhaust gas discharged from an oil rotary vacuum pump, and the like. Can be used publicly as.

1 Filter 2 Pleated anti 21 Inflow side folded part 22 Outflow side folded part 23 Between pleated parts 3 Spacer 31 Mountain part 32 Valley part 33 Intermediate valley part 4 Outer winding 5 End plate 6 Inner circumference side (inflow side)
7 Outer circumference side (outflow side)
8 Inner cylinder 9 Outer cylinder 10 Outer winding filter medium

Claims (8)

A spacer used for pleated type filters that allow fluid to flow from one side to the other.
Attached between the pleated parts on the other side of the pleated fabric,
Not continuous with other spacers attached between other adjacent pleats,
A valley portion arranged at a position facing the other side surface side of the inflow side folded portion of the pleated fabric, and a valley portion.
It has a mountain portion arranged at a position close to the outflow side folded portion of the pleated fabric, and has a mountain portion.
The number of peaks is more than twice the number of valleys,
The length in the direction along the crease of the pleated fabric is substantially the same as the length in the direction along the crease forming the peak portion and the valley portion of the spacer.
Spacer. A spacer used for a cylindrical pleated type filter that allows fluid to flow from the inner circumference side to the outer circumference side.
It is attached between each pleated part on the outer peripheral side of the pleated fabric molded into a cylindrical shape.
Not continuous with other spacers attached between other adjacent pleats,
A valley portion arranged at a position facing the folded portion on the inner peripheral side of the pleated fabric, and a valley portion.
It has a mountain portion arranged at a position close to the folded portion on the outer peripheral side of the pleated fabric, and has a mountain portion.
The number of peaks is more than twice the number of valleys,
The length in the direction along the crease of the pleated fabric is substantially the same as the length in the direction along the crease forming the peak portion and the valley portion of the spacer.
Spacer. The spacer for a pleated type filter according to claim 1 or 2, wherein a mesh material made of a woven fabric of thermoplastic synthetic resin fibers having an aperture ratio of 30% or more and 70% or less is used as the spacer material. The spacer for a pleated type filter according to claim 1 or 2, wherein a mesh material made of an extruded net of a thermoplastic synthetic resin having an aperture ratio of 30% or more and 70% or less is used as the spacer material. The spacer for a pleated type filter according to claim 3 or 4, wherein a mesh material made of a thermoplastic synthetic fiber cut out by heat cutting or ultrasonic cutting or an extruded net material made of a thermoplastic synthetic resin is used. The spacer for a pleated type filter according to claim 1 , which has an intermediate valley portion that folds back from the inflow side toward the outflow side at an intermediate point of the pleated portion of the pleated fabric. The spacer for a pleated type filter according to claim 2 , which has an intermediate valley portion that is folded back from the inner peripheral side to the outer peripheral side at an intermediate point of the pleated portion of the pleated fabric.
An oil mist separator in which the spacer according to claim 1 to 7 is attached between the pleats.