JP2006088104A - Air filter apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain the cost reduction of a structure for preventing intrusion of trash into an outflow port of a case when a filter element is detached from the case. <P>SOLUTION: An air filter apparatus 1 is constituted in such a manner that the case 3 provided with an inflow port 10 and the outflow port 12 freely attachably and detachably holds the filter element 2 constituted by arranging blockade members 22, 23 at both end parts of a filter medium 21 that is formed in a cylinder shape and has a plurality of folds 26 in a peripheral direction, wherein a communication port 25 formed in the blockade member 22 is communicated with the inflow port 10 and an outer peripheral side of the filter medium 21 is communicated with the outflow port 12. Thereby gas flowing-in from the inflow port 10 flows from inside of the filter medium 21 toward its outside and is filtered and trash caught by the filter medium 21 stays inside the filter element 2. Thus, the trash can be prevented from intruding into the outflow port 12 of the case 3 when the filter element 2 is detached and an inner filter element provided in a conventional air filter apparatus as a countermeasure against trash becomes unnecessary. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an air filter device that filters gas.

  Conventionally, in an air filter device used for an engine mounted on an automobile or a construction machine, in general, in order to increase the filtration capacity while reducing the size of the device, the filter medium is formed in a cylindrical shape in the circumferential direction. Cylindrical filter media with a ridge formed with a plurality of ridges are employed. The filter medium is unitized as a filter element, and the entire filter element can be replaced.

  Such a conventional air filter device will be described with reference to FIGS. In the air filter device 101, a filter element 103 is provided inside the case 102, and the filter element 103 can be taken out by opening the lid 104 of the case 102. The case 102 is provided with an inlet 105 through which air flows in and an outlet 106 through which air flows out. The outlet 106 is in communication with the engine. The filter element 103 is provided with a cylindrical filter medium with a flange. In the air filter device 101, the air flowing in from the inlet 105 passes through the filter medium 107 from the outer peripheral surface of the filter medium 107 to the inner peripheral surface of the filter element 103 and flows into the filter element 103. At this time, filtration is performed by the filter medium 107. Thereafter, air is supplied from the outlet 106 to the engine. In this way, air is allowed to flow from the outside to the inside of the filter medium 107, so that the outside of the basket functions as a dust reservoir.

  In this structure, dust such as trapped dust adheres to the outer peripheral surface of the filter medium 107 of the filter element 103. Therefore, when the filter element 103 is removed for replacement or the like, dust adhering to the outer peripheral surface of the filter medium 107 may peel from the filter medium 107 and fall into the case 102. In order to prevent the scattered dust from entering the engine from the outlet 106 of the case 102, the case 102 is provided with an inner filter element 108 that is positioned inside the filter element 103 and communicated with the outlet 106. The inner filter element 108 captures scattered dust.

  However, providing the inner filter element 108 to prevent dust from entering the engine when the filter element 103 is removed causes problems such as a complicated structure of the air filter device 101 and increased cost. To do.

  An object of the present invention is to reduce the cost of the structure for preventing dust from entering the outlet of the case when the filter element is removed from the case.

  An object of the present invention is to provide an air filter device that can prevent dust from entering the outlet of the case when the filter element is removed from the case with a simple structure.

  An air filter device according to a first aspect of the present invention is formed into a hollow shape by a filter medium formed in a cylindrical shape and having a plurality of ridges in the circumferential direction, and blocking members provided at both ends of the filter medium. It has a filter element in which the inside and the outside communicate with each other by the provided communication port and the filter medium, and has an inflow port through which gas flows in and an outflow port through which gas flows in, and the filter element is detachable inside. The communication port is communicated with the inflow port, and the outer peripheral side of the filter medium is communicated with the outflow port.

  According to a second aspect of the present invention, in the air filter device according to the first aspect, in the filter medium, an outer bent portion positioned on the outer peripheral side and bent toward the inner peripheral side, and an outer peripheral portion positioned on the inner peripheral side from the outer bent portion. Inner bent portions bent sideways are alternately provided in the circumferential direction to form the ridges.

  According to a third aspect of the present invention, in the air filter device according to the second aspect of the present invention, the air filter device further includes a restricting portion that restricts a decrease in the interval between the inner bent portions.

  According to a fourth aspect of the present invention, in the air filter device according to the third aspect, the restricting portion is a protrusion that is provided on the filter medium and protrudes inside the ridge.

  According to a fifth aspect of the present invention, in the air filter device according to the second, third or fourth aspect, as the inner bent portion, an inner bent portion at a position close to a central axis of the filter medium, and a position far from the central axis of the filter medium. The inner bent portion at a position close to the central axis of the filter medium and the inner bent portion at a position far from the central axis of the filter medium alternately in the circumferential direction with the outer bent portion in between. Is provided.

  According to the present invention, it is possible to reduce the cost of the structure for preventing dust from entering the outlet of the case when the filter element is removed from the case.

  According to the present invention, it is possible to provide an air filter device that can prevent dust from entering the outlet of the case when the filter element is removed from the case with a simple structure.

  A first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a longitudinal front view schematically showing an air filter device 1 of the present embodiment. As shown in FIG. 1, the air filter device 1 is provided with a case 3 that detachably holds a filter element 2 therein.

  The case 3 includes a case body 4 having an upper side opened and a lid 5 that opens and closes the upper side of the case body 4. A plurality of hooks 6 (only one is shown in the figure) are provided at the lower part of the outer periphery of the lid 5 as fixing means for fixing the lid 5 to the case body 4. The lid 5 is fixed to the case body 4 by engaging these hooks 6 with an engagement portion 7 formed on the upper portion of the case body 4. A packing 8 is sandwiched between the case main body 4 and the lid 5, whereby the airtightness between the case main body 4 and the lid 5 is maintained. Here, FIG. 2 shows the air filter device 1 in a state in which the locking with respect to the locking portion 7 by the hook 6 is released, the lid 5 is opened, and the filter element 2 is taken out. Note that the fixing means for fixing the lid 5 to the case main body 4 is not limited to locking by the hook 6, and may be screwed by a screw (not shown), for example.

  The upper wall 9 of the lid 5 is provided with an inlet 10 for allowing a gas such as air to be filtered to flow into the case 3. The bottom wall 11 of the case body 4 is provided with an outlet 12 for allowing gas to flow out from the inside of the case 3. The inflow port 10, the outflow port 12, and the filter element 2 are arranged on the same axis.

  The filter element 2 will be described. FIG. 3 is a horizontal sectional view showing the filter element 2. As shown in FIGS. 2 and 3, the filter element 2 is formed in a cylindrical hollow shape with a pair of upper and lower caps 22 and 23 serving as blocking members fixed to both ends in the axial direction of a cylindrical filter medium 21. Further, a cylindrical metal mesh member 24 that covers the outer peripheral side of the filter medium 21 is provided between the caps 22 and 23.

  The caps 22 and 23 are formed in a disc shape. A communication port 25 that communicates the inside and the outside of the filter element 2 is provided at a substantially central portion of the upper cap 22. The caps 22 and 23 are airtight at both ends of the filter medium 21 so that the gas flowing into the filter element 21 from the communication port 25, that is, the gas flowing into the filter medium 21 flows through the filter medium 21 to the outside of the filter element 2. It has a function to hold. In the filter element 2, the inside and the outside of the filter element 2 communicate with each other by the communication port 25 and the filter medium 21.

  The filter medium 21 is formed in a cylindrical shape as described above, and a plurality of ridges 26 are provided in the circumferential direction. In the filter medium 21, these ridges 26 are located on the outer peripheral side and bent to the inner peripheral side, and to the inner bent side 28 located on the inner peripheral side than the outer bent portion 27 and bent to the outer peripheral side. Are formed alternately in the circumferential direction. Such a filter medium 21 is formed by bending a sheet-shaped filter medium into a bellows shape so that mountain folds and valley folds are alternately positioned, and connecting both ends thereof into a cylindrical shape. A plurality of pores (not shown) are formed in the filter medium 21, and the filter medium 21 filters gas by this structure. Examples of the material of the filter medium 21 include paper and metal.

  Further, the inner surface 29 of the filter medium 21 is provided with a protrusion 30 that is a restricting portion that restricts the interval between the inner bent portions 28 from being reduced. The protrusion 30 is formed in a shape protruding from the inner surface 29 to the inside of the flange 26, and more specifically, one of the opposing surfaces 29a and 29b facing each other on the inner side of the flange 26 for each flange 26. Are provided in a straight line in the vertical direction. Such a protrusion 30 can be provided, for example, by adhering a resin hot melt to the filter medium 21.

  Here, another example of the restricting portion will be described with reference to FIG. FIG. 4 is an enlarged perspective view showing another example of the filter medium 21 as viewed from the inner peripheral side. As the restricting portion, a protrusion 31 formed by protruding a part of the inner bent portion 28 of the filter medium 21 on both sides, that is, the inside of the flange 26 may be provided for each inner bent portion 28. Such a protrusion 31 is configured such that when a crease is formed on the sheet-like filter medium in order to form the inner bent portion 28 of the filter medium 21, the fold line is not attached to a portion where the protrusion 31 is formed, and The filter medium 21 is bent along the fold line to form the inner bent portion 28. In addition, as a control part, it does not restrict to what was demonstrated so far, What is necessary is just to control that the space | interval of the inner bending part 28 becomes small. For example, the regulating portion may be realized by increasing the rigidity of the filter medium by attaching a long reinforcing material to the inner bent portion 28 in the vertical direction.

  Next, the attachment structure of such a filter element 2 is demonstrated. First, a description will be given from the bottom. As shown in FIGS. 1 to 3, a plurality of step-shaped (three in the present embodiment) fitting pieces 32 are radially positioned on the outer periphery of the cap 23 on the lower side of the filter element 2. It is fixed. These fitting pieces 32 constitute a fitting portion 33 on the filter element 2 side. On the other hand, an annular lower fitting portion 34 having a step shape in which the fitting portion 33 of the filter element 2 is detachably fitted inside is provided at the lower portion inside the case body 4. In a state where the fitting portion 33 of the filter element 2 is fitted to the lower fitting portion 34, a flow path 35 that connects the outer peripheral side of the filter medium 21 and the outlet 12 of the case body 4 is formed inside the case 3. Is done.

  As an upper mounting structure, an annular upper fitting portion 36 having a step shape with which the upper cap 22 of the filter element 2 is fitted is provided inside the lid 5. In a state where the upper cap 22 of the filter element 2 is fitted to the upper fitting portion 36, a flow path 37 that connects the inlet 10 of the lid 5 and the communication port 25 of the filter element 2 is formed inside the case 3. Is done. At this time, the inflow port 10 communicates only with the communication port 25 of the filter element 2 through the flow path 37 inside the case 3.

  In this structure, the lid 5 is closed with the fitting portion 33 of the filter element 2 fitted to the lower fitting portion 34 of the case body 4, and the lid 5 is fixed to the case body 4 by the hook 6. Thus, the upper cap 22 of the filter element 2 is fitted into the upper fitting portion 36 of the lid 5, and the filter element 2 is sandwiched between the case body 4 and the lid 5 and fixed to the case 3. This fixing is released by opening the lid 5, whereby the filter element 2 can be taken out from the case 3.

  The metal mesh member 24 covers the outside of the filter medium 21 to prevent the filter medium 21 from being deformed to the outer peripheral side. The metal mesh member 24 has a plurality of holes (not shown), and these holes are formed to have a larger diameter than the holes of the filter medium 21.

  In such a configuration, the flow of the gas to be filtered flowing into the case 3 from the inlet 10 is indicated by arrows in FIG. The gas that flows into the case 3 from the inlet 10 flows along the flow path 37 and flows into the filter element 2 from the communication port 25. The gas that has flowed into the filter element 2 passes through the filter medium 21 and the metal mesh member 24, flows out of the filter element 2, and then flows along the flow path 35 to reach the outlet 12 of the case 3. And flows out of the air filter device 1. At this time, dust such as dust or dust contained in the gas is captured by the filter medium 21 in the process of moving together with the gas and removed from the gas.

  At this time, gas flows in from the communication port 25 of the filter element 2, moves from the inside of the filter medium 21 to the outside and passes through the filter medium 21, so that the inside of the tub 26 functions as a dust reservoir and is captured by the filter medium 21. The collected dust is accumulated inside the filter medium 21. Thereby, the dust captured by the filter medium 21 exists inside the filter element 2 and does not exist on the outer peripheral side of the filter element 2. Therefore, when the filter element 2 is removed from the case 3 for replacement or cleaning, the dust trapped by the filter medium 21 due to vibration or the like remains in the filter element 2 even if it is separated from the filter medium 21, so that the filter medium 21 is trapped. It is possible to prevent the collected dust from falling outside the filter element 2. Therefore, the dust trapped by the filter medium 21 is prevented from falling into the case 3 and the dust is prevented from entering the outlet 12.

  In the conventional air filter device, in order to increase the filtration capacity of the filter medium, the outside of the basket functions as a dust reservoir as a structure for passing gas from the outside to the inside of the filter medium for filtration. On the other hand, in the air filter device 1 of the present embodiment, cost reduction and simplification of a structure for preventing dust from entering the outlet 12 of the case 3 when the filter element 2 is removed from the case 3. In order to remove the filter element 2, the communication port 25 of the filter element 2 is communicated with the inlet 10 of the case 3 and the outer periphery of the filter medium 21 is communicated with the outlet 12 as described above. This prevents dust from entering the outlet 12. Therefore, in the air filter device 1 of the present embodiment, the inner filter element 108 provided to prevent dust from entering the outlet 106 when the filter element 103 is removed in the conventional air filter device 101 is provided. There is no need to provide this, and the cost of the structure for preventing dust from entering the outlet 12 when removing the filter element 2 can be reduced as compared with the conventional case. Moreover, it is possible to prevent dust from entering the outlet 12 when the filter element 2 is removed with a simple structure as compared with the conventional case.

  Further, conventionally, since gas flows from the outside to the inside of the filter medium, it is provided inside the metal core member filter medium for preventing the filter medium from being deformed inward by the gas flow. In the form, since the gas is allowed to flow from the inside to the outside of the filter medium 21, such a core member is not necessary.

  Further, in the filtration process as described above, a force is applied to the filter medium 21 so that the adjacent inner bent portions 28 of the filter medium 21 move in a direction in close contact with each other due to the gas flow from the inside to the outside of the filter medium 21. May be. In this case, the low-rigid filter medium 21 such as paper is easily affected by the force, but in the present embodiment, for example, the protrusion 30 is used as a restricting portion that restricts the interval between the inner bent portions 28 from being reduced. Since the filter medium 21 is provided with a small gap between the filter media 21, the inner bent portions 28 adjacent to each other in the filter media 21 are prevented from being completely brought into close contact with each other to prevent the lid 26 from closing. The Accordingly, it is possible to prevent the filtration capacity of the filter medium 21 from being reduced due to the closure of the trough 26.

  Moreover, in this Embodiment, a control part can be made into a simple structure because the control part is the protrusion 30 or 31 which was provided in the filter medium 21 and protruded inside the collar 26. FIG.

  Further, in the present embodiment, in the filter medium 21, an outer bent portion 27 located on the outer peripheral side and bent toward the inner peripheral side, and an inner bent portion positioned closer to the inner peripheral side than the outer bent portion 27 and bent toward the outer peripheral side. 28 are alternately provided in the circumferential direction to form the flange 26, whereby the flange 26 is realized with a simple structure.

  Next, a second embodiment of the present invention will be described with reference to FIG. The same parts as those of the above-described embodiment are denoted by the same reference numerals and description thereof is also omitted.

  In the air filter device 1, the structure that reduces the cost and simplifies the structure for preventing dust from entering the outlet 12 when the filter element 2 is removed. Since it functions as a dust reservoir, the filtration capacity becomes smaller than that of a conventional air filter device. Therefore, an example of means for increasing the filtration capacity of the air filter device 1 will be described below.

  FIG. 5 is a horizontal sectional view showing the filter medium 51 of the present embodiment. In the present embodiment, the shape of the filter medium 51 is different from that of the first embodiment. Filter medium 51 of the present embodiment is formed in an M-fold shape. Specifically, there are two types of inner bent portions 28, an inner bent portion 28a at a position close to the central axis 51a of the filter medium 51 and an inner bent portion 28b at a position far from the central axis 51a of the filter medium 51. The inner bent portion 28a and the inner bent portion 28b are alternately provided in the circumferential direction with the outer bent portion 27 interposed therebetween. Thereby, seeing from the top, the filter medium 51 has a shape in which a plurality of “M” characters are arranged in the circumferential direction.

  With such a configuration, the filter medium 51 is an inner bend that is an inner bend located on the innermost peripheral side under the condition of obtaining the same filtration area as the filter medium 21 of the first embodiment that is not M-folded. The interval between the portions 28 b can be made wider than the interval between the inner bent portions 28 in the filter medium 21. Thereby, the capacity | capacitance inside the eaves 26, ie, a dust storage capacity, becomes large, and it can enlarge a filtration capacity compared with the filter medium 21. FIG.

1 is a longitudinal front view schematically showing an air filter device according to a first embodiment of the present invention. It is a vertical front view which shows the air filter apparatus of the state from which a cover is opened and a filter element is taken out from a case. It is a horizontal sectional view showing a filter element. It is a perspective view which expands and partially shows another example of a filter medium. It is a horizontal sectional view which shows the filter medium of the 2nd Embodiment of this invention. It is a vertical front view which shows the conventional air filter apparatus roughly. It is a vertical front view which shows the air filter apparatus of the state from which a cover is opened and a filter element is taken out from a case.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air filter apparatus 2 Filter element 3 Case 10 Inflow port 12 Outlet 21 Filter medium 22 Closure member 23 Closure member 25 Communication port 26 襞 27 Outer bending portion 28 Inner bending portion 30 Restriction part, Protrusion part 31 Restriction part, Protrusion part 51 Filter medium 51a Center axis

Claims (5)

It is formed in a hollow shape by a filter medium having a plurality of ridges in the circumferential direction and a blocking member provided at both ends of the filter medium, and the inside is formed by the communication port provided in the blocking member and the filter medium. A filter element communicating with the outside,
A case having an inflow port through which gas flows in and an outflow port through which gas flows in, and detachably holding the filter element therein;
With
An air filter device in which the communication port is in communication with the inflow port, and the outer peripheral side of the filter medium is in communication with the outflow port.   In the filter medium, the outer bent portion positioned on the outer peripheral side and bent toward the inner peripheral side and the inner bent portion positioned closer to the inner peripheral side than the outer bent portion and bent toward the outer peripheral side are alternately provided in the circumferential direction, and The air filter device according to claim 1, wherein a ridge is formed.   The air filter device according to claim 2, further comprising a restricting portion that restricts a decrease in an interval between the inner bent portions.   The air filter device according to claim 3, wherein the restricting portion is a protrusion that is provided on the filter medium and protrudes to the inside of the ridge. As the inner bent portion, comprising an inner bent portion at a position close to the central axis of the filter medium, and an inner bent portion at a position far from the central axis of the filter medium,
The inner bent portion at a position close to the central axis of the filter medium and the inner bent portion at a position far from the central axis of the filter medium are alternately provided in the circumferential direction with the outer bent portion interposed therebetween. The air filter device according to 3 or 4.

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