JPS6218831Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to abnormality detection in an intake/exhaust device used in an intake/exhaust type combustor.

[Conventional technology]

Various detection devices have been proposed that detect an abnormality when at least one of the intake and exhaust pipes of the combustor becomes blocked, and take safety measures such as stopping the operation of the combustor. 1976-- which detects when the pressure on the side or discharge side is negative or positive compared to the normal atmospheric pressure.
140734 and Utility Model Application No. 52-165334 and Utility Model Application No. 54-2240 which are equipped with a pressure detector between the intake and exhaust passages to detect abnormalities are known.

[Problems to be solved by the invention] Generally, in order to detect abnormalities in the air guide path from intake to exhaust air, there is a method of detecting the pressure before and after the fan, as disclosed in Utility Model Application No. 140734/1983, for example. However, the abnormal state that can be detected by this method is the stoppage of rotation of the fan, and a normal state is also indicated when a portion of the intake and exhaust pipe is blocked due to external conditions.

On the other hand, Jitsukasho detects the pressure difference between the exhaust passage and the intake passage.
Methods such as No. 52-165334 and Utility Model Publication No. 54-2240 are
Depending on the mounting position of the pressure detection pipe, fluctuations in outside air pressure may cause malfunctions, and even if intake and exhaust pipe blockages can be detected, they may not be compatible with all modes; for example, even if intake pipe blockages can be detected, There were malfunction conditions such as a malfunction occurring when the exhaust pipe was blocked, and a malfunction occurring when the intake and exhaust pipes were simultaneously blocked.

[Means for solving problems]

In order to solve the above-mentioned drawbacks, this invention was developed by discovering a pressure detection part that can detect all abnormal states in the method of detecting pressure differences between various parts and detecting abnormal states. To explain, 1 is an intake fan that supplies combustion air to the combustion section, 2 is an exhaust fan that discharges combustion exhaust gas from the combustion section, and the intake fan 1 is in the intake path to the combustor.
Further, an exhaust fan 2 is attached to the exhaust path from the combustor. 3 is a wind pressure switch consisting of a pressure switch, and the wind pressure switch 3 connects a negative pressure pipe 4 to the negative pressure side 4' of the wind pressure switch 3, and connects a positive pressure pipe 6 to the negative pressure side 6' of the wind pressure switch 3. 5
is a scroller of the exhaust fan 2, and the negative pressure pipe 4 opens into a gap between the exhaust fan 2 and the scroller 5. Further, the positive pressure pipe 6 is an air guide path 7 between the intake fan 1 and a combustion section (not shown).
It is open to

8 is a motor for driving the intake fan 1 and the exhaust fan 2; 9 is an exhaust pipe connected to an intake/exhaust top (not shown); and 10 is an intake pipe.

[Explanation of action]

Since the configuration is as described above, in this invention, when the motor 8 is energized, the intake fan 1 rotates to increase the pressure in the air guide path 7 to the combustor, and when the exhaust fan 2 rotates, the intake and exhaust air is increased. By the way, in this invention, the negative pressure pipe 4 of the wind pressure switch 3 is opened in the gap between the exhaust fan 2 and the scroller 5, and this opening is designed to increase the pressure in the exhaust pipe 9 to the top. Because it is inside the fan rather than the discharge part, the exhaust fan 2 and the scroller 5
The pressure appears lower than the pressure at the fan discharge section because of the entrainment effect of the fast airflow caused by the rotation of the fan. Therefore, the pressure difference between the positive pressure pipe 6 that opens into the air guide path 7 of the intake fan 2, which is the discharge part of a similar fan, and the negative pressure pipe 4 that opens into the scroller 5 of the exhaust fan 2 is as follows. The pressure on the positive pressure pipe 6 side is high, indicating a normal state.

On the other hand, in this device in which the negative pressure and positive pressure pipes 4 and 6 are installed in this way, when the intake pipe 9 is blocked, there is no escape route for the air, and the discharge part of the fan becomes under abnormally high pressure, causing the inside of the scroller 5 to become abnormally high. However, the pressure on the negative pressure pipe 4 becomes higher than the pressure on the positive pressure pipe 6,
The wind pressure switch 3 detects an abnormality.

Moreover, when the intake pipe 10 is blocked, the intake fan 1
The pressure in the air guide path 7, which is the discharge part of It detects abnormalities.

Furthermore, when both the intake and exhaust pipes 10 and 9 are closed, the pressure in the air guide path 7, which is the discharge part of the intake fan 1, does not rise, and on the other hand, the exhaust fan 2 has no air escape route, and the negative pressure pipe 4 The pressure applied to the wind pressure switch 3 increases and the wind pressure switch 3 detects an abnormality.

Furthermore, when the motor 8 that drives the fan stops, both the negative pressure pipe 4 and the positive pressure pipe 6 reach almost atmospheric pressure, and there is no pressure difference between the positive pressure and negative pressure pipes 6 and 4, so the wind pressure switch 3 becomes abnormal. This is to detect.

[Explanation of effects]

As described above, the system that detects an abnormality in the intake and exhaust pipes by detecting the pressure difference between the intake and exhaust passages shows normality despite the abnormality in modes 1 and 2 that cause the abnormality. However, according to the structure of the wind pressure switch of this invention that specifies the connections of the positive pressure and negative pressure pipes, trouble modes such as single blockage of the intake and exhaust pipes, blockage of both pipes, and motor stoppage can all be solved by the wind pressure switch. In addition, when an abnormality occurs, the pressure difference between the positive pressure and negative pressure pipes is reversed except when the motor is stopped, making it possible to detect an abnormality. It has characteristics.

[Brief explanation of drawings]

FIGS. 1 and 2 are cross-sectional views of this device in use. 1...Air supply fan, 2...Exhaust fan, 3
...Wind pressure switch, 4...Negative pressure pipe, 4'...
Negative pressure side of wind pressure switch, 5...Scroller, 6...
...Positive pressure pipe, 6'...Positive pressure side of wind pressure switch,
7...Air guide path.

Claims (1)

[Scope of utility model registration request] An intake fan 1 is installed on an intake passage for supplying combustion air to the combustion section, and an exhaust fan 2 is attached on an exhaust passage for discharging exhaust gas from the combustion section, between the intake passage and the exhaust passage. In a forced exhaust combustor with a wind pressure switch 3 interposed, the negative pressure pipe 4 of the wind pressure switch 3 is opened in the gap between the exhaust fan 2 and the scroller 5, and the positive pressure pipe 6 of the wind pressure switch 3 is opened for intake. The suction/exhaust system is characterized in that it monitors the differential pressure of a wind pressure switch 3 that opens into the air guide path 7 between the fan 1 and the combustion section, and in normal conditions, the negative pressure side 4' is negative and the positive pressure side 6' is positive. Tracheal blockage detection device.