JPH06142426A - Air sucking device - Google Patents

Abstract

PURPOSE:To surely detect the clogging of an air filter with a simple constitution by disposing a pressure sensor in the peripheral plane part of a funnel-shaped part where static pressure prevails without an air filter being clogged. CONSTITUTION:A fan 2 where an eye part 211 of an impeller 21 faces a funnel- shaped part 31, a pressure sensor 5 disposed in a peripheral plane part 32 of the funnel-shaped part 31 and an air filter 4 disposed upstream of the funnel- shaped part 31 at a specified distance from the peripheral plane part 32 are provided. And when the pressure sensor 5 detects a negative pressure equal to or more than a specified value, the air filter 4 is judged to be clogged. By this simple constitution, the clogging of the air filter is surely detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air suction device such as an air purifier or a warm air heater having an air filter.

[0002]

2. Description of the Related Art As shown in FIG. 6, an air filter 101 and a blower 10 are installed in a housing 100 in order from the upstream side.
2. The heat exchanger 103 is provided, the indoor air is taken into the housing 100 through the suction duct 104, dust and the like are removed by the air filter 101, and clean air is exchanged with the heat exchanger 10.
In the air conditioner that sends the air-conditioning air from the air outlet (not shown) to the air conditioner 3, if the air filter 101 is clogged with dust due to long-term use, the amount of intake air decreases and combustion becomes defective. There is a fear. Therefore, there has been proposed a technique for detecting whether or not the air filter 101 is clogged as described below.

As shown in FIG. 7, a pressure sensor 201 is arranged on the downstream side of the air filter 101, and when the detection means 301 detects a decrease in wind pressure due to accumulation of dust, the control means 302 operates the display means 303. Air filter 1
The clogging of 01 is detected (conventional example 1).

As shown in FIG. 8, pressure sensors 201 and 202 are arranged on the downstream and upstream sides of the air filter 101,
When the detection means 301 detects the difference in wind pressure due to the accumulation of dust, the control means 302 operates the display means 303 to detect clogging of the air filter (Japanese Patent Publication No. 3-191227; Conventional Example 2).

[0005]

The above-mentioned conventional techniques have the following problems. Since the wind pressure drop due to the accumulation of dust on the air filter 101 is extremely small, high accuracy is required to detect the wind pressure drop. Further, it is particularly difficult when the rotation speed of the blower 102 changes (conventional example 1). Wind pressure-electrical output characteristics of each pressure sensor are different (due to variations and deterioration)
Even if the air filter 101 is not clogged,
The detection means 301 erroneously detects "clogging" (conventional example 2).

An object of the present invention is to provide an air inhaler which has a simple structure and can reliably detect clogging of an air filter.

[0007]

[Means for Solving the Problems] In order to solve the above problems,
The present invention is a fan in which the center part of the impeller faces a funnel-shaped part,
The pressure sensor is provided on a peripheral flat surface portion of the funnel-shaped portion, and an air filter is disposed upstream of the funnel-shaped portion with a predetermined size from the peripheral flat surface portion. When a negative pressure equal to or higher than the value is detected, the air filter is in a clogged state.

[0008]

In the state where the air filter is not clogged, the room air is taken in from the air filter upstream of the funnel-shaped portion and reaches the eyeball portion of the blower, so the pressure sensor detects the static pressure. When the air filter starts to be clogged, the room air is also taken in from the air filter at the peripheral flat surface position of the funnel-shaped portion, and the pressure sensor detects the negative pressure. If the air filter becomes clogged,
Further, the room air is taken in from the air filter at the peripheral peripheral flat surface position, and the negative pressure value detected by the pressure sensor is increased.

[0009]

Since the pressure sensor is provided on the peripheral flat surface of the funnel-shaped portion, clogging of the air filter can be reliably detected with a simple structure.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FE type fan heater A adopting the constitution of the present invention
Is a casing 1, a combustion fan 2 for sucking indoor air 20, a bell mouth 3, an air filter 4 arranged upstream of the bell mouth 3, and a funnel-shaped portion 31 of the bell mouth 3.
And a pressure sensor 5 disposed on the peripheral flat surface portion 32 of the.

In the casing 1 having a box shape, a circular opening 111 is formed in the back plate 11, and the opening 111 is formed in the cylindrical body 11.
2 (inner diameter about 5 cm) penetrates. Reference numeral 12 denotes a fan housing disposed on the inner wall side of the back plate 11, which has an air intake port 1
21 is formed, from which the cylindrical body 112 is fixed in a protruding state. 13 is a heat exchanger provided in a ventilation duct 14 and having a burner (not shown) inside, 15 is an air supply duct connecting the fan housing 12 and the heat exchanger 13, and 16 is exhaust gas generated in the heat exchanger 13. An exhaust duct for discharging outdoors, 17 is a hot air outlet 171 and an outlet 141
Is a convection fan for ejecting air from the inside into the room 170.

In the combustion fan 2, an impeller 21 (multi-blade type) is installed inside the fan housing 12 so that the eyeball portion 211 faces the funnel-shaped portion 31, and the combustion air corresponding to the combustion amount is a heat exchanger. 13, the impeller 21 has a motor 22
Is driven to rotate at a predetermined rotation speed.

The bell mouth 3 is formed by bending a thin metal plate, is inserted into the air intake port 113 of the cylindrical body 112, and is in parallel with the back plate 11 and the funnel-shaped portion 31 whose passage has a smaller diameter toward the back. And a side plate portion 33 that is bent from the edge of the peripheral flat surface portion 32 toward the casing 1 (right angle) and has its tip fixed to the back plate 11. With. The bell mouth 3 is provided to prevent a sound generated when the room air 20 is sucked into the cylindrical body 112.

The net-like air filter 4 (mesh # 30) is placed outside the bell mouth 3 so as to enclose the bell mouth 3 with a predetermined size (5 mm) from the peripheral flat surface portion 32 and the side plate portion 33. A suspended matter such as dust is removed from the indoor air 20 that is installed and inhaled.

The pressure sensor 5 is an element that outputs an electric signal corresponding to wind pressure. In this embodiment, the pressure sensor 5 includes a pressure sensitive portion (not shown) and an air tube 51 led out from the pressure sensitive portion. The tip 511 is disposed on the peripheral flat surface portion 32 closest to the funnel-shaped portion 31 where the static pressure (zero wind pressure) occurs when the air filter 4 is not clogged.

Next, in the FE type fan heater A,
The principle of detecting clogging of the air filter will be described with reference to FIG. [The state where the air filter 4 is not clogged] When dust or the like does not adhere to the air filter 4, as shown in Fig. 2, almost all of the room air 20 flows from the air filter 4 upstream of the funnel-shaped portion 31. Since it is taken in and enters the fan housing 12 from the air intake port 111, the pressure sensor 5
Detects static pressure.

[State where the air filter 4 starts to be clogged] When the air filter 4 starts to clog, the indoor air 20 is taken in from the air filter 4 located on the peripheral flat surface portion 32 as shown in FIG. Then, the pressure sensor 5 starts to detect the negative pressure.

[State where the air filter 4 is clogged]
When the clogging of the air filter 4 progresses, as shown in FIG. 2, the indoor air 20 is further taken in from the air filter 4 located on the peripheral flat portion 32, and the negative pressure value detected by the pressure sensor 4 rapidly increases. . In the present embodiment, the predetermined value from the pressure sensor 5 (-25mm~-30mmH ₂ O)
When an electric signal corresponding to a negative pressure exceeding 0 is sent, a clogging notification controller (not shown) notifies that the air filter 4 is clogged.

Next, the advantages of this embodiment will be described. (A) According to the above-described principle, a large pressure difference can be obtained between the case where the air filter 4 is not clogged and the case where the air filter 4 is clogged, so that the clogging of the air filter 4 can be reliably detected. Even when the combustion fan 2 is rotating at a low speed (the burner in the heat exchanger 13 is slightly burning), the negative pressure can be detected (when it is clogged), so that the air filter 4 can be easily operated. Can detect clogging.

(A) The peripheral flat surface portion 32 of the bell mouth 3 which has a static pressure when the air filter 4 is not clogged.
Since only the pressure sensor 5 is provided in the structure, the structure is simple and the increase in manufacturing cost can be prevented.

(C) Since the mesh air filter 4 is arranged outside the bell mouth 3 so as to cover the bell mouth 3 at a predetermined distance from the peripheral flat surface portion 32 and the side plate portion 33, Even if the air filter 4 is clogged, the indoor air 20 is located on the peripheral flat surface portion 32 or the like.
Since it is sucked from the air, the amount of introduced air hardly decreases, and there is no fear that combustion will be defective.

The present invention includes the following embodiments in addition to the above embodiments. a. If the cylindrical body 112 is not provided, the funnel-shaped portion 31 of the bell mouth 3 may be configured to be inserted into the air inlet 121 as shown in FIG. In this case, the air filter 4 is provided at a predetermined distance from the peripheral flat surface portion 32. Also in this case, the pressure sensor 5 is provided between the peripheral flat portion 32 and the air filter 4. Further, as shown in FIG. 4, the funnel-shaped portion 31 may extend from the air inlet 121, and as shown in FIG. 5, the funnel-shaped portion 31 extends so as to be inserted into the air inlet 121. Is also good. Also in these cases, the air filter 4 is provided at a distance from the back plate 11, and the pressure sensor 5 is provided between the back plate 11 and the air filter 4. b. The pressure sensor has a structure including only the pressure-sensitive portion without the air tube 51, and the pressure-sensitive portion is directly connected to the peripheral flat surface portion 32.
It may be arranged in.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an FE type fan heater according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a transition of an indoor air introduction path due to a difference in clogging degree of an air filter.

FIG. 3 is a cross-sectional view of main parts showing another structure of the funnel-shaped part of the bell mouth.

FIG. 4 is a sectional view of an essential part showing another structure of the funnel-shaped part of the bell mouth.

FIG. 5 is a cross-sectional view of main parts showing another structure of the funnel-shaped part of the bell mouth.

FIG. 6 is a schematic view of an air conditioner.

FIG. 7 is a schematic view of an air conditioner adopting a conventional technique.

FIG. 8 is a schematic view of an air conditioner adopting a conventional technique.

[Explanation of symbols]

 A FE type fan heater (air suction device) 2 Combustion fan (blower) 4 Air filter 5 Pressure sensor 21 Impeller 31 Funnel-shaped part 32 Peripheral plane part 211 Eyeball part

Claims (1)

[Claims] 1. A blower in which the center portion of an impeller faces a funnel-shaped portion, a pressure sensor arranged on a peripheral flat surface portion of the funnel-shaped portion, and the funnel-shaped portion of the funnel-shaped portion at a predetermined distance from the peripheral flat surface portion. An air suction device comprising: an air filter arranged upstream; and when the pressure sensor detects a negative pressure equal to or higher than a predetermined value, the air filter is in a clogged state.