JP3631815B2 - Forced supply / exhaust blower - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a forced air supply / exhaust blower, and more particularly to a blower that forcibly supplies and exhausts air with one fan and one motor.
[0002]
[Prior art]
This type of forced supply / exhaust blower has an exhaust fan and an air supply fan mounted coaxially on each of the rotating shafts protruding forward and backward from the motor as disclosed in Japanese Utility Model Publication No. 3-57336 and Japanese Utility Model Application Publication No. 3-57337. The exhaust fan and the supply fan are each housed in separate casings.
In such a structure, it is necessary to prepare two casings independent of the two fans, and the motor must have a structure having a rotating shaft at the front and rear, so that an increase in manufacturing cost can be avoided. Can not.
[0003]
[Problems to be solved by the invention]
Therefore, the applicant of the present invention applied to the casing 1 a double-sided suction type multi-blade fan 2 that is divided into two axially by a power transmission plate 12 provided vertically in an intermediate portion as disclosed in Japanese Patent Application No. 7-80873. A forced air supply / exhaust blower is proposed in which the casing 1 is housed and partitioned into an exhaust chamber 100 and an air supply chamber 200 by a partition wall 71 provided on an extension line of the power transmission plate 12.
The previously proposed one can supply / exhaust air with one fan and one casing, and can greatly reduce the manufacturing cost.
However, as shown in FIG. 4 , a space 8 that does not obstruct the rotation of the power transmission plate 12 between the partition wall 71 and the power transmission plate 12 and the partition wall 71 must be secured between the partition wall 71. There is a possibility that exhaust gas may be mixed into the air supply passage 200 or the supply air into the exhaust passage 100 through the air inlet 8, and it is particularly preferable to supply an air-fuel mixture mixed with fresh fresh air into the indoor living space. It was not.
[0004]
The present invention has been made in view of the conventional circumstances, and a technical problem thereof is a means in which exhaust and air supply are not mixed with each other in a forced air supply / exhaust fan provided with one fan and one casing. It is to attach.
[0005]
[Means for Solving the Problems]
The technical means taken in order to achieve the above-mentioned object is as follows. Claim 1 contains a double-blade suction type multi-blade fan divided in the axial direction by a power transmission plate provided vertically in an intermediate portion, and a multi-blade fan A forced air supply / exhaust fan that is partitioned into an exhaust chamber and an air supply chamber by a partition wall provided at a position corresponding to the power transmission plate , and is fitted to a peripheral end of the power transmission plate. The gist of the invention is that an overlap structure with a small gap is formed between the fixed elastic film and the partition wall.
[0006]
According to the above technical means, as a result of constituting an overlap structure with a small gap between the elastic membrane fitted and fixed to the peripheral edge of the power transmission plate and the partition wall, the elastic membrane is an exhaust chamber facing the elastic membrane or It bends elastically so as to reduce the small gap by the air pressure in the air supply chamber, further reducing the gap and creating a large flow path resistance .
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
1 to 3 show a range hood fan containing a forced air supply / exhaust fan according to the present invention, wherein A is a forced air supply / exhaust fan, B is a hood main body containing the forced air supply / exhaust fan A, and 3 is the forced air supply / exhaust fan. The exhaust duct 4 connected to the air supply / exhaust fan A is an air supply duct connected to the air supply chamber 5, and oily smoke, odors, etc. generated by cooking are sent from the forced air supply / exhaust fan A through the exhaust duct 3. is discharged outdoors, fresh outside air outside is adapted to be air supply into the room from the forced air supply and exhaust blower a through the air supply chamber 5 from the air supply duct 4.
[0008]
The forced air supply / exhaust fan A includes a casing 1 and a multiblade fan 2 accommodated in the casing 1, and a motor 7 that drives the multiblade fan 2 is fixed to the outside of the casing 1.
[0009]
The casing 1 has a well-known volute shape, and is covered with a front plate 11 having an attachment / detachment hole 11a for the multiblade fan 2 on the front side in the axial direction and a rear plate 21 having an opening 21a on the rear side. The bell mouth 31 is screwed into the attaching / detaching hole 11a to form an exhaust suction port 41, and the curved bell mouth 51 is bent inside the opening 21a mouth of the rear plate 21 so that the suction port 61 is formed. A partition wall 71 is provided vertically in the middle portion between the suction ports 41 and 61 before and after the formation.
[0010]
The partition wall 71 has a volute-shaped casing 1 divided into two front and rear parts, and has an opening 71a that is concentric with the multi-blade fan 2 to be described later. The provided power transmission plate 12 divides the inside of the casing 1 into an exhaust path 100 and an air supply path 200.
[0011]
The multi-blade fan 2 includes an upper plate 32 and a lower plate 42 having a donut plate shape, blades 22 installed and fixed between the upper plate 32 and the lower plate 42, and between the upper plate 32 and the lower plate 42. And a circular power transmission plate 12 provided.
[0012]
Specifically, each blade 22 has a side view shape in which a wide blade portion 22a and a narrow blade portion 22b are continuous via an intermediate step portion 22c, and the direction of the intermediate step portion 22c is staggered. After inserting the crimping allowances 22d on both ends into the insertion holes 32a and 42a opened on the upper plate 32 and the lower plate 42, the crimping allowances 22d are crimped to form a bridge. It is fixed.
[0013]
The power transmission plate 12 divides the multi-blade fan 2 into a front exhaust fan section 2 'and a rear air supply fan 2 ", and is provided with insertion holes 12a in portions corresponding to the blades 22. As described above, the blades 22 installed and fixed on the upper plate 32 and the lower plate 42 are inserted through the insertion holes 12a so that the directions of the intermediate step portions 22c are staggered, and the intermediate step portions 22c group are inserted into the insertion holes 12a. By being alternately locked to the front side of the hole edge and the rear side of the hole edge, the intermediate part of the multiblade fan 2 is sandwiched and fixed.
[0014]
The power transmission plate 12 has a slightly larger diameter than the front exhaust fan portion 2 ′ and the rear air supply fan 2 ″, and is made of rubber or soft plastic that is fitted and fixed to the peripheral end portion thereof. An overlapping structure in which the small gap 6 is separated by the elastic film 9 and the partition wall 71 is formed.
[0015]
The air supply chamber 5 to which the air supply duct 4 is connected is attached over the back plate b1 and the top plate b2 of the hood main body B.
An opening 15 a is provided in the front surface portion 15 of the air supply chamber 5, and the blower A has a half portion of the motor 7 supported via a cross-shaped mounting leg 81 provided on the rear plate 21 of the casing 1. It is attached to the inside from the opening 15a of the front surface portion 15 in a housing shape.
[0016]
The multiblade fan 2 has a nut from the exhaust chamber 100 side to a boss portion 12b fixed to the central portion of the power transmission plate 12 on a motor shaft 7a inserted through the center of the suction port 61 provided on the rear plate 21 of the casing 1. Stopped and assembled.
[0017]
When the forced air supply / exhaust fan A of this embodiment having such a configuration is operated, the exhaust chamber 100 is configured to discharge exhaust gas, odor, etc. generated by cooking from the front inlet 41 through the filter. In parallel with the air intake, fresh outdoor air outside is sucked into the air supply chamber 200 through the air supply duct 4 and the opening 15a of the air supply chamber 5, and the exhaust air is taken outside through the exhaust duct 3 and fresh outdoor air. Are discharged from the slit b2 'provided in the top plate b2.
At that time, the elastic membrane 9 that is fitted and fixed to the peripheral end portion of the driving force transfer plate 12 as described above, the positional relationship facing at a small clearance 6 to increase the flow path resistance with respect to the opening 71 a of the partition 71 Therefore, the exhaust gas in the exhaust chamber 100 is mixed into the air supply chamber 200 due to the gas flow preventing action by the small gap 6, and conversely fresh fresh air in the air supply chamber 200 is mixed into the exhaust chamber 100. It can prevent dripping.
In addition, when the exhaust pressure of the exhaust chamber 100 facing the elastic film 9 is larger than the supply pressure of the supply chamber 200 , the small gap 6 can be further bent to increase the flow resistance. Therefore, it is particularly effective in preventing the undesirable exhaust gas from being mixed into the supply air.
Further, after removing the front bell mouth 41, the fan 2 can be cleaned and inspected by unscrewing the nut and removing the multiblade fan 2 from the attachment / detachment hole 11a.
In addition, it is also free to project protrusions on the component surface of the partition wall 71 that forms the small gap 6 or to apply flocking. In this case, the protrusions and the flocks are prevented from contacting each other so as not to cause rotational resistance of the power transmission plate 12 . With this configuration, the flow path resistance is further increased, and preferable results are obtained.
[0018]
【The invention's effect】
As described above, the present invention configures an overlap structure in which a small gap is formed between the elastic membrane fitted and fixed to the peripheral edge of the power transmission plate and the partition so that the small gap generates a large flow path resistance. Therefore, it is possible to prevent the exhaust near the power transmission plate from being mixed into the air supply chamber and the air supply from being mixed into the exhaust chamber.
In addition, when the exhaust pressure of the exhaust chamber facing the elastic membrane is higher than the supply air pressure, the elastic membrane bends elastically so as to reduce the small gap, thereby preventing particularly undesirable exhaust gas from being mixed into the supply air. Demonstrate the effect.
[Brief description of the drawings]
FIG. 1 is a partially cutaway side view of a range hood fan incorporating a forced air supply / exhaust fan of the present invention .
FIG. 2 is an exploded perspective view of a multiblade fan .
FIG. 3 is an enlarged cross-sectional view of a main part of a multiblade fan .
FIG. 4 is an enlarged sectional view showing a relationship between a power transmission plate of a multiblade fan and a partition wall of a casing in a conventional example .
[Explanation of symbols]
2: Multi-blade fan 1: Casing
100: Exhaust chamber 200: Supply chamber
71: Bulkhead 6: Small gap
12: Power transmission plate 9: Elastic membrane

Claims (1)

A double-sided suction type multi-blade fan divided in the axial direction by a power transmission plate provided vertically in an intermediate portion, and a casing for housing the multi-blade fan, and the inside of the casing at a position corresponding to the power transmission plate In a forced air supply / exhaust fan divided into an exhaust chamber and an air supply chamber by a provided partition wall, an overlap structure in which a small gap is provided between the elastic film fitted and fixed to the peripheral end of the power transmission plate and the partition wall A blower for forced supply / exhaust characterized by comprising.

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