JP6365344B2 - Filter element for air cleaner - Google Patents

Description

  The present invention relates to a filter element for an air cleaner that filters air with a folded filter medium.

An air cleaner for filtering air is provided in an intake passage of the on-vehicle internal combustion engine. The air cleaner is provided with a filter element having a folded filter material.
Conventionally, such a filter medium has been developed that has a filter paper layer and a nonwoven fabric layer formed of thermoplastic resin fibers and attached to the dusty side of the filter paper layer (for example, patents). Reference 1).

JP 2006-175352 A

  By the way, when it rains, water may be sucked into the intake passage from the intake port. In this case, when the sucked-in water adheres to the filter medium of the filter element, the filter medium absorbs water and the rigidity of the filter medium decreases. In particular, in a filter medium having a non-woven fabric layer, since the non-woven fabric layer tends to increase the ventilation resistance of the filter medium, the basis weight of the filter paper layer is often reduced in order to suppress an increase in the ventilation resistance of the filter medium. Therefore, when the filter paper layer absorbs water, the rigidity tends to be low. At this time, if the intake negative pressure is increased due to clogging of the filter medium or the like, there is a possibility that inconvenience such as large deformation occurs due to the reduced rigidity of the filter element.

  In the filter element described in Patent Document 1, the dusty side surface of the filter medium is formed by a nonwoven fabric layer formed of fibers of thermoplastic resin, and the same surface has water repellency. However, since the filter paper layer is exposed to the outside at both ends of the filter medium in the extending direction of the ridge line of the ridge, that is, in the width direction of the filter element, both ends of the filter paper layer in the width direction are wetted with water. As a result, the filter paper layer absorbs water and its rigidity decreases, which may cause the inconvenience described above.

  The objective of this invention is providing the filter element which can suppress generation | occurrence | production of the inconvenience resulting from a filter paper layer absorbing water.

  A filter element for achieving the above object is a filter element that filters air with a folded filter medium, and the filter medium is formed of a filter paper layer and fibers of a thermoplastic resin and is formed on a dusty side of the filter paper layer. A non-woven fabric layer affixed to the surface, and when the direction in which the ridge line of the ridge extends is the width direction of the filter element, the non-woven fabric layer is the clean side of the filter paper layer at the end of the filter paper layer in the width direction. It is folded back.

  According to this configuration, the nonwoven fabric layer is exposed to the outside at the end of the filter medium in the width direction of the filter element, and the filter paper layer is not exposed to the outside. For this reason, it can suppress appropriately that the edge in the said width direction of a filter paper layer gets wet with water, and can suppress that the filter paper layer absorbs water.

  According to the present invention, it is possible to suppress the occurrence of inconvenience due to the filter paper layer absorbing water.

The perspective view of one Embodiment of a filter element. FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. The side view seen from the arrow A direction of FIG. The side view which shows the process of bonding the filter paper layer and the nonwoven fabric layer in the embodiment. The top view which shows the process of bonding the filter paper layer and the nonwoven fabric layer in the embodiment. Sectional drawing along line 6-6 in FIG. Sectional drawing along line 7-7 in FIG. The perspective view of the state by which the filter medium in the same embodiment was folded up. The perspective view of the state in which the edge part sealing part was formed about the filter medium in the embodiment.

  Hereinafter, an embodiment of the filter element will be described with reference to FIGS. The filter element 10 of the present embodiment is applied to an air cleaner for an in-vehicle internal combustion engine.

  As shown in FIG. 1, the filter element 10 includes a filter medium 11 that is folded in a square shape in plan view, a rectangular frame-shaped seal portion 12 provided on the outer peripheral edge of the filter medium 11, a direction in which the ridge line of the ridge extends, That is, an end sealing portion 13 that seals both ends 111 of the filter medium 11 in the width direction of the filter element 10 (hereinafter simply referred to as the width direction L) is provided.

  As shown in FIGS. 1 to 3, the filter medium 11 includes a filter paper layer 20 and a non-woven fabric layer attached to the dusty side of the filter paper layer 20 (the lower side in the figure and the upstream side in the air flow direction). 30. The nonwoven fabric layer 30 is made of thermoplastic resin fibers and has water repellency.

  The nonwoven fabric layer 30 includes a main body portion 31 (see FIG. 2) attached to the entire dusty side surface of the filter paper layer 20, and a clean side of the filter paper layer 20 at the end 21 of the filter paper layer 20 in the width direction L (same figure). And a folded portion 32 (see FIG. 3) folded back in the air flow direction). The width of the folded portion 32 is preferably 10 mm to 15 mm, for example. This is because if the width of the folded portion 32 is too small, it is difficult to fold the nonwoven fabric layer 30 and it is difficult to attach the folded portion 32 to the filter paper layer 20. This is because if the width of the folded portion 32 is too large, the ventilation resistance of the filter medium 11 is deteriorated. Therefore, the filter paper layer 20 is exposed in most of the filter medium 11 on the clean side surface except the folded portion 32. In addition, as a thermoplastic resin which forms the nonwoven fabric layer 30, a polypropylene (PP) and a polyethylene terephthalate (PET) are preferable, for example. Moreover, in order to efficiently capture fine particles having a particle diameter of about 0.5 μm contained in the air by the nonwoven fabric layer 30, the fiber diameter of the nonwoven fabric layer 30 is preferably 0.7 to 15 μm, and the basis weight of the nonwoven fabric layer 30 is 9 ˜15 g / m 2 is preferred.

The seal portion 12 is made of closed-cell polyurethane.
The end sealing portion 13 is a hot-melt adhesive, and the end sealing portion 13 has each end 111 of the filter medium 11 in the width direction L so that the end sealing portion 13 does not protrude outside the filter medium 11. It is provided inside.

Next, the manufacturing process of the filter medium 11 will be described with reference to FIGS.
As shown in FIG. 4, by rotating the winding roller 43, the filter paper layer 20 wound around the filter paper roll 41 is wound and the nonwoven fabric layer 30 wound around the nonwoven fabric roll 42 is wound up. A guide roller 44 is provided between the nonwoven fabric roll 42 and the take-up roller 43 to guide the non-woven fabric layer 30 moving toward the take-up roller 43 so as to be parallel to the filter paper layer 20.

  At this time, as shown in FIG. 5, the filter paper layer 20 and the nonwoven fabric layer 30 have the same center C in the width direction. Moreover, as shown in FIG. 6, the width W2 of the nonwoven fabric layer 30 is made larger than the width W1 of the filter paper layer 20 (W2> W1).

  As shown in FIGS. 4 and 5, a guide member 45 and a pair of heating rolls 46 a and 46 b are provided between the guide roller 44 and the take-up roller 43 in order from the guide roller 44 side. A plurality of protrusions are formed on the peripheral surfaces of the heating rolls 46a and 46b at predetermined intervals in the axial direction.

  As shown in FIGS. 5 and 7, the filter paper layer 20 and the nonwoven fabric layer 30 pass through the guide member 45, so that the portion protruding from the filter paper layer 20 in the width direction of the nonwoven fabric layer 30 is the end of the filter paper layer 20. Folded inward in the width direction so as to include 21.

  The filter paper layer 20 and the nonwoven fabric layer 30 are embossed by passing between a pair of heating rolls 46a and 46b. That is, the non-woven fabric layer 30 is partially melted by heat received from the protrusions and bonded to the filter paper layer 20. And the filter medium 11 is formed by cutting what the nonwoven fabric layer 30 affixed on the filter paper layer 20 to predetermined length.

  Thereafter, as shown in FIG. 8, the filter medium 11 is folded along the width direction of the filter medium 11. And as shown in FIG. 9, the edge part sealing part 13 is formed by apply | coating a hot-melt-adhesive inside the edge 111 in the width direction L of the filter medium 11. As shown in FIG. Finally, the seal portion 12 is formed on the outer peripheral edge of the filter medium 11.

Next, the operation of this embodiment will be described.
At the end of the filter medium 11 in the width direction L, the nonwoven fabric layer 30 is exposed to the outside, and the filter paper layer 20 is not exposed to the outside. For this reason, it can suppress appropriately that the edge 21 in the said width direction L of the filter paper layer 20 gets wet with water, and can suppress that the filter paper layer 20 absorbs water and the rigidity falls. Therefore, even when the intake negative pressure increases due to clogging of the filter medium 11 or the like, it is possible to suppress the occurrence of inconvenience such as the filter element 10 being greatly deformed.

According to the filter element according to the present embodiment described above, the following effects can be obtained.
(1) The filter medium 11 of the filter element 10 has a filter paper layer 20 and a non-woven fabric layer 30 formed of thermoplastic resin fibers and attached to the dusty side surface of the filter paper layer 20. The nonwoven fabric layer 30 is folded back to the clean side of the filter paper layer 20 at the end 21 of the filter paper layer 20 in the width direction L of the filter element 10.

  According to such a configuration, the filter paper layer 20 can be prevented from absorbing water. Therefore, the occurrence of inconvenience caused by the filter paper layer 20 absorbing water can be suppressed.

(2) On the inner side of the end 111 of the filter medium 11 in the width direction L, an end sealing portion 13 separate from the filter medium 11 is provided.
According to such a configuration, the end sealing portion 13 can appropriately suppress air from flowing into the clean side through the valley of the end 111 of the filter medium 11 without passing through the filter medium 11 itself.

  Therefore, according to the present embodiment, while providing the end sealing portion 13 inside the end 111 of the filter medium 11 in the width direction L, the occurrence of inconvenience due to the filter paper layer 20 absorbing water is suppressed. can do.

  (3) The main body portion 31 and the folded portion 32 of the nonwoven fabric layer 30 are simultaneously bonded to the filter paper layer 20 by embossing. For this reason, the filter medium 11 can be manufactured efficiently.

<Modification>
In addition, the said embodiment can also be changed as follows, for example.
-The filter paper layer 20 and the nonwoven fabric layer 30 can also be affixed by a lamination process. That is, a hot-melt sheet having high air permeability is sandwiched between the filter paper layer 20 and the nonwoven fabric layer 30 and bonded by heating and pressing.

-The nonwoven fabric layer 30 immediately after formed by the melt blow method etc. can also be affixed on the filter paper layer 20. FIG.
The end sealing portion 13 can also be formed by melting a part of the folded portion 32 of the nonwoven fabric layer 30 at the end of the filter medium 11 in the width direction L. In this case, a hot melt adhesive is not necessary.

  DESCRIPTION OF SYMBOLS 10 ... Filter element, 11 ... Filter medium, 111 ... End, 12 ... Seal part, 13 ... End part sealing part, 20 ... Filter paper layer, 21 ... End, 30 ... Nonwoven fabric layer, 31 ... Main-body part, 32 ... Folding part, 41 ... filter paper roll, 42 ... non-woven fabric roll, 43 ... winding roller, 44 ... guide roller, 45 ... guide member. 46a, 46b ... heating rolls.

Claims (3)

In a filter element for an air cleaner that filters air with a folded filter medium,
The filter medium has a filter paper layer, and a nonwoven fabric layer formed of thermoplastic resin fibers and attached to the dusty side of the filter paper layer,
When the direction in which the edge of the ridge extends is the width direction of the filter element,
The nonwoven fabric layer is folded back to the clean side of the filter paper layer at the end of the filter paper layer in the width direction,
Filter element for air cleaner. Inside the end of the filter medium in the width direction is provided with an end sealing portion separate from the filter medium,
The filter element for an air cleaner according to claim 1. The end portion of the filter medium in the width direction is provided with an end sealing portion formed by melting a folded portion folded back on the clean side of the filter paper layer in the nonwoven fabric layer.
The filter element for an air cleaner according to claim 1.