JP2011144759A - Foreign matter collecting device for axial flow blower - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a foreign matter-removing ratio by trapping the foreign matters as sure as possible, and to improve heat radiation effect by efficiently feeding air supplied from an axial flow blower into a casing. <P>SOLUTION: The air A1 discharged from a discharge port 3 of the axial flow blower 1 spatters in a form of a spiral flow toward a second opening part 16 of a first tube body 11, while swirling radially outside of an impeller 6. A foreign matter collecting device 10 for an axial flow blower includes: the first tube body 11 having a first opening part 15 opposed to the discharge port 3 and a second opening part 16; and a second tube body 12 forming a foreign matter collecting space 23 formed between the first tube body 11 and the second tube body 12. The air A1 discharged from the discharge port 3 passes through slits 17 of the first tube body 11, and is collided with an inner surface of the second tube body 12. At that time, foreign matters C are adhered to the inner surface of the cylinder 12, and the air A1 from which the foreign matters are removed passes through the slits 17 and is discharged from the second opening part 16. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a foreign matter collecting apparatus for an axial blower that collects foreign matters such as oil mist and dust contained in air discharged from an axial blower.

  In electronic devices and devices that have a heating element built into the housing, in order to suppress the effect of heat on the mounted components due to the rise in the temperature of the housing, outside air is introduced into the housing using an axial fan, A forced air cooling method may be employed in which the inside of the housing is circulated and discharged to the outside. In this case, if foreign matter such as oil mist or dust (hereinafter simply referred to as foreign matter) is contained in the air introduced into the housing by the axial blower, the electronic components mounted in the device In order to have an adverse effect, it was necessary to take some measures.

  As a device that has taken this measure, there is a foreign matter collecting device for an axial blower that has been filed and implemented by the applicant of the present application described in Patent Document 1. The foreign matter collecting apparatus for an axial blower described here includes a dust removing hood provided outside the discharge port of the blower casing, and the hood surrounds the peripheral portion of the discharge port, and the cylindrical portion. An inner flange portion projecting from the tip of the tube, an annular space portion formed by the inner flange portion and the tubular portion, and an annular space portion through an opening provided in a part of the tubular portion And a duct for discharging dust that extends in a tangential direction of the annular space. Therefore, of the air discharged from the discharge port, air including dust and the like is swung along the annular space due to the centrifugal force due to its own weight, and is discharged from the dust discharge duct. On the other hand, clean air that does not contain dust or the like is fed from an opening provided in the center of the inner flange portion into a housing containing a heating element.

Japanese Utility Model Publication No. 63-105800

  In the conventional foreign matter collecting apparatus for an axial blower described above, air containing foreign matter such as dust is discharged from the dust discharge duct only by the centrifugal force generated by the dead weight of the foreign matter. There is a problem in that satisfactory removal is not necessarily performed because foreign matters whose outer shape is relatively small and centrifugal force does not act greatly cannot be reliably removed. In addition, since air containing foreign matter is not directly guided to the opening of the duct but indirectly through the annular space, the trapping rate of foreign matter trapped in the opening is reduced. There was also a fear of doing. Furthermore, since air containing foreign matter is discharged from the duct together with the foreign matter, the amount of air supplied into the housing is reduced by that amount, and there is a problem that the heat dissipation effect is reduced.

  The present invention has been made in view of the above-described conventional problems. The object of the present invention is to improve the foreign matter removal rate by capturing foreign matter as reliably as possible and to supply air supplied from an axial blower. It is to improve the heat dissipation effect by efficiently feeding the material into the housing.

  In order to achieve this object, the present invention is a foreign matter collecting apparatus for an axial blower that is attached to the outside of a discharge port of an axial blower and collects foreign matters contained in the air discharged from the discharge port. A cylindrical first tube body provided with a first opening facing the discharge port and a second opening for discharging air at the other end, and around the first tube body A cylindrical second cylinder surrounding the first and second cylinders, and a doughnut-shaped sealed foreign matter collection space is formed between the first and second cylinders, and the first cylinder In addition, a large number of air passage openings are provided for guiding the air discharged from the discharge outlet to the outside in the radial direction of the axial blower into the foreign matter capturing space and colliding with the inner surface of the second cylindrical body. It is a thing.

  According to the present invention, in the above invention, the second cylinder is provided with a foreign matter discharge hole for discharging the foreign matter collected in the foreign matter collection space to the outside.

  According to the present invention, in any one of the above inventions, a plurality of the first cylinders are provided concentrically between the second cylinders.

  According to the present invention, in any one of the above inventions, the air passage port is a slit made of a long hole extending in the axial direction of the first cylindrical body and arranged in parallel in the circumferential direction. Are uniformly provided on the entire surface of the first cylindrical body.

  According to the present invention, when the air containing a foreign substance passes through the air passage port, the second cylinder reliably ensures that the foreign substance is not only caused by the centrifugal force acting on the air but also by the principle of the orifice so that the flow velocity of the air increases. Since it is carried to the inner surface of the body, the foreign matter removal rate for removing foreign matter from the air is improved. In addition, since the air that has carried the foreign object to the inner surface of the second cylinder passes through the air passage port again and is discharged from the second opening portion, all of the air discharged from the discharge port of the axial blower is It is discharged from the second opening. For this reason, since the air volume of the air discharged | emitted from a 2nd opening part does not fall, the heat dissipation effect improves. In addition, there is nothing between the first opening and the second opening that obstructs the flow of air discharged from the discharge port of the axial blower like a filter, so the air discharged from the discharge port Since no pressure loss occurs, the airflow is not reduced and the heat dissipation effect is improved. In addition, the air passage opening can have a wide opening area, the structure is simple, and maintenance is easy, and since the air passage opening is always cleaned by blowing air, the maintenance interval is increased. This reduces the load required for maintenance.

  According to one of the inventions, since the foreign matter collected in the foreign matter collection space is discharged to the outside, the maintenance interval can be lengthened.

  According to one of the inventions described above, since the number of air passing ports is increased, the amount of foreign matter trapped at the edge of the air passing port is increased, so that the foreign matter catching rate can be improved.

  According to one of the inventions described above, the slit of the first cylindrical body is formed by a long hole that is long in the axial direction of the axial blower, so that the length of the hole edge compared to the circular hole is increased. And the number of collision surfaces against the air flow increases, so that the trapping efficiency of foreign matter can be increased. In addition, since the slit is provided over the entire first cylindrical body, air discharged in all directions from the discharge port toward the first cylindrical body can be directly collected by the slit, so that the foreign matter removal rate Can be improved.

It is a perspective view which shows the state which attached the foreign material collection | recovery apparatus for axial flow fans which concerns on this invention to the axial flow fan. It is sectional drawing which shows the state which attached the foreign material collection | recovery apparatus for axial flow fans which concerns on this invention to the axial flow fan. In the foreign material recovery apparatus for an axial-flow fan according to the present invention, it is an enlarged view of a main part showing a state where air passes through a slit. In the state which attached the foreign material collection device for axial flow fans concerning the present invention to an axial flow fan, in order to explain a movement course, air is a side view broken and shown. FIG. 5 is a perspective view seen from the back side in order to explain a state in which foreign matter collected in the foreign matter collection space is collected in the foreign matter collection device for an axial blower according to the present invention. It is the perspective view which looked at the state which attached the foreign material collection device for axial flow fans concerning the present invention to the axial flow fan from the bottom side. It is a perspective view which shows the modification of the foreign material collection | recovery apparatus for axial flow fans which concerns on this invention.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  1 and FIG. 2 is an axial blower that has been widely known in the past, and is provided with a suction port 2 at one end, a discharge port 3 at the other end, and both ends opened. A fan case 4 formed in a cylindrical shape is provided. The fan case 4 includes a driving motor 5 fixed to the fan case and an impeller 6 driven by the driving motor 5.

  In such a configuration, when the impeller 6 is rotationally driven, the air A sucked from the suction port 2 is rotated in the rotational direction of the impeller 6 toward the outer side in the radial direction of the impeller 6 as shown in FIG. Air flow in the same direction as (clockwise) occurs. Therefore, the air A1 discharged from the discharge port 3 of the axial flow fan 1 turns along the axial direction of the axial flow fan 1 as shown in FIG. It moves as a vortex toward the second opening 16 of the first cylinder 11 to be described later.

  A foreign matter collecting apparatus for an axial flow fan (hereinafter simply referred to as a collecting apparatus) according to the present invention, indicated as a whole by reference numeral 10, has a first cylinder 11 and a second cylinder both of which are open at both ends and formed into a cylindrical shape. 12 is provided.

  One end of the first cylindrical body 11 is formed with the same diameter as the discharge port 3 of the axial flow fan 1 as described later, and a first opening 15 facing the discharge port 3 is provided. The other end is provided with a second opening 16 having the same diameter as the first opening 15. The first cylindrical body 11 is provided with slits 17 made up of a large number of thin holes as air passage openings. That is, all the slits 17 having the same length and the same width are extended in the axial direction, and many slits 17 are arranged in the circumferential direction.

  A part of the second cylindrical body 12 having a structure to be described later is provided with a foreign matter discharge hole 20 for discharging foreign matter as shown in FIG. The diameter of the second cylinder 12 is formed to be larger than the diameter of the first cylinder 11, and the entire lengths of the first and second cylinders 11 and 12 are the same.

  As shown in FIG. 2, these first and second cylinders 11 and 12 are openings formed between both ends so that the second cylinder 12 surrounds the first cylinder 11 concentrically. Is closed by a pair of ring-shaped closing plates 21 and 22. Due to the blockage, the first and second cylinders 11 and 12 and the block plates 21 and 22 form a doughnut-shaped sealed foreign matter collection space 23.

  Next, the operation | movement which collects foreign materials, such as oil mist and dust, from the air discharged from the discharge outlet 3 of the axial blower 1 by the collection | recovery apparatus 10 comprised in this way is demonstrated. First, as shown in FIG. 2, the first opening 15 of the recovery device 10 is opposed to the discharge port 3 of the axial blower 1 attached to a device (not shown), and foreign matter is discharged as shown in FIG. The recovery device 10 is attached to the axial blower 1 so that the hole 20 is positioned at the lowermost position of the recovery device 10.

  In this state, by driving the driving motor 5 of the axial blower 1 and rotating the impeller 6, a flow of air A is generated toward the outside in the radial direction of the impeller 6. Therefore, the air A1 discharged from the discharge port 3 of the axial flow fan 1 is directed to the second opening 16 along the axial direction of the axial flow fan 1 as shown in FIG. It scatters as a vortex to turn outward in the direction.

  At this time, if the air A sucked from the suction port 2 contains foreign matter C such as oil mist or dust that has been suspended in the atmosphere, the foreign matter C is also present in the air A1 discharged from the discharge port 3. include. Since the air A1 containing the foreign matter C is heavier than the air containing no foreign matter, the air A1 moves toward the surface of the first cylindrical body 11 by the centrifugal force acting on the outer side in the radial direction of the impeller 6. Scatter.

  Since a large number of slits 17 are provided on the surface of the first cylindrical body 11, the air A <b> 1 passes through the slits 17 as shown in FIG. 3 and collides with the inner surface of the second cylindrical body 12. . Due to this collision, the foreign matter C contained in the air A1 adheres to the surface of the second cylinder 12 as shown in FIG. 2, and is collected in the foreign matter collection space 23. Here, when the air A1 passes through the slit 17, the flow rate of the air A1 increases due to the orifice principle that the flow rate increases when the fluid passes from a thick tube through a small diameter hole.

  For this reason, the foreign matter C contained in the air A1 is reliably conveyed to the inner surface of the second cylindrical body 12 and reliably adheres to the inner surface of the second cylindrical body 12. The foreign matter removal rate from which C is removed is improved. In addition, by providing the slit 17 uniformly on the entire surface of the first cylinder 11, air A <b> 1 discharged from the discharge port 3 toward the first cylinder 11 in all directions is directly collected by the slit 17. Therefore, the foreign matter removal rate can be improved.

  After the foreign matter C adheres to the inner surface of the second cylindrical body 12, the air A1 that does not contain the foreign matter collides with the surface of the second cylindrical body 12, and then, as shown in FIG. 11 is reflected, passes through the slit 17 again, and is discharged from the second opening 16.

  On the other hand, when the air A1 passes through the slit 17 and contacts the hole edge of the slit 17, the foreign matter C1 contained in the air A1 collides with the hole edge of the slit 17 and is captured. In this case, as shown in FIG. 2, the foreign air C <b> 1 is carried toward the second cylinder 12 by the subsequent air A <b> 2 passing through the slit 17 and collides with the inner surface of the second cylinder 12. It adheres and is collected in the foreign matter collection space 23.

  Here, the slit 17 of the first cylindrical body 11 is formed by a long hole that is long in the axial direction of the axial blower 1, and as a synergistic effect, the trapping efficiency of foreign matter is compared with the case where it is formed in a circular shape. Can be increased. That is, the air A1 and A2 discharged from the discharge port 3 and containing foreign substances are swirl flows toward the axial direction of the axial blower 1, and therefore, obliquely with respect to the axial direction of the axial blower 1 as shown in FIG. Flowing.

  In this way, the slit 17 is formed by a long hole, and is formed and arranged so as to be inclined obliquely with respect to the air A1 and A2, in other words, the collision surface is increased with respect to the flow of the air A1 and A2. Therefore, when air A1 and A2 containing foreign matter repeatedly collide with the hole edge of the slit 17, many foreign substances adhere to the hole edge of the slit 17 and are captured and removed, resulting in an increase in the capture efficiency. it can.

  In addition, when the air A3 that does not include foreign matter is discharged from the discharge port 3 into the first cylinder 11, the centrifugal force that acts on the air A3 toward the outside in the radial direction of the impeller 6 is small. As shown in FIG. 3, the air is discharged from the second opening 16 as it is without going to the inner surface of the first cylinder 11.

  As described above, all of the air A1 to A3 discharged from the discharge port 3 of the axial blower 1 is from the second opening 16 of the recovery device 10 regardless of whether or not it contains foreign matter. Discharged. For this reason, since the air volume of the air discharged | emitted from the 2nd opening part 16 does not fall, the heat dissipation effect improves. Moreover, since there is nothing which interrupts the movement of the air discharged from the discharge port 3 of the axial flow fan 1 like a filter between the 1st opening part 15 and the 2nd opening part 16, from the discharge port 3 Since no pressure loss occurs in the discharged air, the airflow is not reduced and the heat dissipation effect is improved.

  In addition, the slit 17 can have a wide opening area and has a simple structure, so that maintenance is easy, and since the slit 17 is always cleaned by blowing air, the maintenance interval is increased. Therefore, the maintenance load can be reduced.

  The foreign matter C and C1 collected in the foreign matter collection space 23 becomes a large lump every time the foreign matter C and C1 collected in the foreign matter collection space 23 collides next. The foreign substances C and C1 that have become large lumps have the air A1 and A2 that have entered the foreign substance collection space 23 through the slit 17 and are rotating in the same direction as the rotation direction of the impeller 6. As shown in FIG. 5, the wind pressure moves clockwise along the inner surface of the second cylindrical body 12 and is discharged from the foreign matter discharge hole 20 to the outside.

  As described above, since the foreign substances C and C1 collected in the foreign substance collection space 23 can be discharged to the outside from the foreign substance discharge hole 20, the cleaning interval in the foreign substance collection space 23 can be increased. Become.

  Next, a modification of the present invention will be described with reference to FIG. This modification is different from the above-described embodiment in that a large number of small holes 27 provided at equal intervals are used as air passage openings instead of the plurality of slits 17 in the above-described embodiment. Also in this embodiment, air A1 and A2, which are discharged from the discharge port 3 of the axial blower 1 and contain foreign matter, pass through the small hole 27 and collide with the surface of the second cylindrical body 12, and the air A1 , A2 is collected in the foreign matter collection space 23 by adhering to the surface of the second cylindrical body 12.

  In this embodiment, the example in which the air passage openings are the slits 17 and the small holes 27 has been described. However, a large number of openings provided in a mesh shape may be used. In addition, a plurality of the first cylinders 11 may be provided concentrically between the second cylinders 12. In this case, since the number of slits 17 increases, the foreign matter capture rate by the slits 17 is increased. improves.

  Table 1 compares the trapping rate of foreign matter and the air flow rate reduction rate at the slit 17 and the mesh-like opening as an air passage port. As shown in Table 1, it can be seen that when the number of the air passage openings is “slit” or “mesh-like opening”, the air flow rate reduction rate can be kept to 10% or less when the number is one. . When the air passage opening is a “slit” and the number of the slits 17 is changed from one to two, the foreign matter capturing rate is improved, but the air volume reduction rate is decreased. Therefore, it is necessary to select whether to give priority to the capture rate or to give priority to the air volume reduction rate. On the other hand, in the case of a mesh-shaped opening, even if the number is increased from one to two, the capture rate is only slightly improved, but the wind power reduction rate is reduced, so there is no point in increasing the number to two. I understand.

  DESCRIPTION OF SYMBOLS 1 ... Axial flow fan, 2 ... Inlet port, 3 ... Discharge port, 10 ... Foreign material collection | recovery apparatus (collection apparatus) for axial flow fans, 11 ... 1st cylinder, 12 ... 2nd cylinder, 15 ... 1st 16 ... second opening, 17 ... slit (air passage port), 23 ... space for collecting foreign matter, 27 ... small hole (air passage port), A, A1, A2, A3 ... air, C, C1 ... Foreign matter.

Claims (4)

A foreign matter collecting device for an axial flow fan that is attached to the outside of the discharge port of the axial blower and collects foreign matter contained in the air discharged from the discharge port,
A cylindrical first cylinder having a first opening opposite to the discharge port at one end and a second opening for discharging air at the other end, and the first cylinder A cylindrical second cylinder surrounding the circumference concentrically, and a doughnut-shaped sealed foreign matter collection space is formed between the first and second cylinders,
A large number for guiding the air discharged from the discharge port to the outside in the radial direction of the axial blower into the first cylindrical body into the foreign matter capturing space and colliding with the inner surface of the second cylindrical body. A foreign matter collecting apparatus for an axial blower characterized in that an air passage opening is provided.   2. The foreign matter collecting apparatus for an axial flow fan according to claim 1, wherein a foreign matter discharging hole for discharging the foreign matter collected in the foreign matter collecting space to the outside is provided in the second cylindrical body. .   The foreign matter collecting apparatus for an axial-flow fan according to claim 1 or 2, wherein a plurality of the first cylindrical bodies are provided concentrically between the second cylindrical bodies.   The air passage opening is a slit made of a long hole extending in the axial direction of the first cylinder and arranged in the circumferential direction, and the slit is provided over the entire first cylinder. The foreign matter collecting apparatus for an axial-flow fan according to any one of claims 1 to 3.

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