JPH08121381A - Ventilating device for vehicle - Google Patents

Abstract

PURPOSE: To indirectly accurately and easily grasp an operation air flow of a ventilation device during mounting of it on a vehicle by providing a mechanism to detect and measure a reference differential pressure between a fan suction port, corresponding to an airflow of a fan, and a spot right before an impeller. CONSTITUTION: A ventilation device 1 mounted on a vehicle comprises a ventilating fan 2; a transmitter 3 for driving a fan, a ventilation duct 4 on the suction side of the ventilation device 1; and a duct 5 on the delivery side. Further, the ventilating device comprises a suction pressure detecting port 6 on the suction side of the ventilating fan 2; a pressure detecting port 8 right before an impeller 7; a differential pressure introduction pipe 9 for detecting a differential pressure; and a differential pressure gauge 10 to measure a differential pressure. This constitution facilitates detection and measurement of a differential pressure during loading of the ventilation device 1 on a vehicle to any time. By using the deferential pressure and one kind of a reference differential pressure - airflow characteristic curve measured and determined during pretesting of factory performance according to JIS, an accurate airflow is grasped.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle ventilation system.

[0002]

2. Description of the Related Art When a vehicle is equipped with a ventilation system for a vehicle, it is installed in a narrow space under a ceiling or under the floor, so that it is impossible to measure the air flow rate according to the JIS standard. Therefore, by measuring the input current of the electric motor for driving the ventilation fan shown in FIG. 3, the air volume is indirectly obtained from the current-air volume characteristic curve shown in FIG. 4 previously measured at the factory performance test. However, in the prior art, since the fluctuation range of the overhead wire voltage of the vehicle is large, the current correlates with the voltage and fluctuates. It was necessary to create as many as possible.

Further, since the shaft power of the ventilation fan changes depending on the suction temperature, the temperature of the current corresponding to the shaft power change is corrected with respect to the reference value of constant voltage / temperature from the relationship of shaft power = current × voltage. There was a need. Therefore, it is necessary to obtain the air volume by using the current-air volume characteristic calibration curve in which the temperature correction of the current value assuming the fluctuation range of the ventilation fan suction temperature is described in advance with respect to the current-air volume curve in FIG. It was As a matter of course, it is necessary to prepare a large number of calibration curves in FIG. 5 according to the voltage fluctuation range.

The current of the ventilation fan motor when mounted on the vehicle is measured using a clamp type ammeter. However, as described above, when the fluctuation of the current due to the fluctuation of the overhead wire voltage is large, the correct current is measured. Is difficult to understand, and in reality, it is very difficult to create FIG. 5, which is a calibration curve of current-air volume characteristics, in which the number of current-air volume characteristics corresponds to fluctuations in voltage. 6 types) A calibration curve corresponding to the voltage fluctuation is created, and the current-air volume characteristic calibration curve corresponding to the approximate voltage is used to obtain the air volume from the voltage at the time of measurement. The accuracy of the indirect airflow calculation method was poor.

If it is not possible to accurately grasp the air volume, the ventilation balance between the air supply and the exhaust air will be disturbed, and the air supply device interlocking with the cooling and heating air conditioner in the vehicle will not supply the appropriate air volume. There is also a problem that the air conditioning does not work well.

A related technique is disclosed in Japanese Patent Laid-Open No. 2-169.
There is an 898 publication. This is a method of obtaining the air volume by utilizing the pressure difference between the suction side and the discharge side. With this method, data is taken in a state where there is no resistance at both the suction port and the discharge port during the factory test, and when the actual device is installed, some resistance is attached to both the suction port and the discharge port, so the data collected in the factory test cannot be used as is. There was a drawback.

[0007]

The above-mentioned prior art has a problem that the operating air volume of the ventilation device cannot be accurately grasped due to the large fluctuation range of the overhead wire voltage / current when the vehicle is mounted. Also, in order to obtain the operating air volume more accurately, it is necessary to create a large amount of conversion correction data for the voltage, current, and fan intake air temperature in advance, and it is necessary to spend a great deal of time in collecting data during factory testing. There was also the problem that it was not realistic. Secondary problems when the air volume cannot be optimized include problems such as imbalance of air supply / exhaust ventilation and cooling / heating performance problems caused by excess or deficiency of the allowable heating / cooling load capacity.

An object of the present invention is to indirectly and accurately determine the operating air volume of a ventilation device when it is mounted on a vehicle.

[0009]

In order to achieve the above object, a detection / measuring mechanism for measuring the reference difference immediately before the impeller and the fan suction side corresponding to the fan air volume of the ventilator main body is installed. Since the reference differential pressure corresponds to the fan air volume on a one-to-one basis,
By measuring and detecting the differential pressure, an accurate air volume can be easily grasped if the differential pressure-air volume characteristic curve is obtained in advance at the factory performance test.

[0010]

In the ventilation system for a vehicle, the difference in static pressure between the wall surface static pressure immediately before the impeller of the ventilation fan and the wall surface static pressure at the inlet of the suction case is usually associated with the intake air volume.

Therefore, a detection seat for measuring the suction side pressure (P _s1 ) which is the upstream side of the fan suction port as a ventilator and the pressure (P _s2 ) immediately before the impeller which is the downstream side is installed in the ventilator body, By instrumenting the static pressure (ΔP) with a differential pressure gauge or the like, it is possible to indirectly and easily obtain an accurate air volume from the reference differential pressure-air volume characteristic curve previously measured and obtained in the factory performance test.

Further, since the pressure of the fan also changes due to the change in the air specific gravity depending on the intake air temperature, the differential pressure (ΔP) converted from the temperature at the time of differential pressure measurement to the reference temperature (ΔP). Although it is necessary to use ′), the conversion formula is as follows and can be easily converted at the differential pressure measurement location.

[0013]

[Equation 1]

From this, it is sufficient to prepare only one kind of standard differential pressure-air volume characteristic curve at the time of factory test, which is required in advance, as the fan characteristic, and the factory test cost can be greatly reduced.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIG.

The ventilator 1 mounted on the vehicle is composed of a ventilation fan 2, an electric motor for driving the fan 3, a suction duct 4 on the intake side of the ventilator 1, and a duct 5 on the discharge side.
Further, a suction pressure detection port 6 and a pressure detection port 8 immediately before the impeller 7 are provided on the suction side of the ventilation fan 2, and a differential pressure introduction pipe 9 for detecting the differential pressure and a differential pressure gauge 10 for measuring the differential pressure are provided. It is composed by. With this configuration, it is possible to easily detect and measure the differential pressure when the ventilation device 1 is mounted on the vehicle. Since the rotation speed of the fan driving electric motor 3 is not affected by changes in the overhead wire voltage and electric wires of the vehicle, the ventilation fan always operates stably, and the differential pressure detected and measured becomes a stable measured value. By using this differential pressure and the reference differential pressure to the air volume characteristic curve, which is previously measured and measured in the factory performance test according to JIS, as shown in FIG. 2, it is possible to indirectly and easily grasp the accurate air volume. It is possible.

Further, the differential pressure gauge 10 has a reference differential pressure shown in FIG.
It is also possible to read the ventilation air volume on the spot by changing to a personal computer that can perform calculation processing from the air volume characteristic curve and the suction temperature.

[0018]

According to the present invention, the relationship between the air volume and the air pressure, which is the basis of the fan characteristics, can be effectively utilized. Therefore, by detecting and measuring the reference differential pressure, the reference differential pressure at the factory performance test according to JIS is performed. ~ It is possible to easily grasp the accurate air volume from the air volume characteristic curve.

Further, since only one type of reference differential pressure-air volume characteristic curve, which is a calibration curve obtained in advance at the time of factory test, is required, it is possible to significantly reduce factory test cost.

[Brief description of drawings]

FIG. 1 is a sectional view showing a reference differential pressure detecting and measuring method according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram of reference differential pressure to air volume during a factory test in which the air volume is grasped using the reference differential pressure measurement value shown in FIG.

FIG. 3 is an explanatory diagram of a conventional ventilation device for indirectly grasping the air volume from a current-air volume characteristic curve.

FIG. 4 is a characteristic diagram of current-air volume during a factory test corresponding to the conventional voltage fluctuation.

5 is a current obtained by adding temperature correction of current to FIG.
Air volume characteristic diagram.

[Explanation of symbols]

1 ... Ventilation device, 2 ... Ventilation fan, 3 ... Electric motor, 4 ... Suction side ventilation duct, 5 ... Discharge side ventilation duct, 6 ... Suction pressure detection port, 7 ... Impeller, 8 ... Pressure detection port immediately before impeller,
9 ... Differential pressure introducing pipe, 10 ... Differential pressure gauge.

Claims (1)

[Claims] 1. A vehicle ventilation system comprising an air supply system and an exhaust system provided with a mechanism for detecting and measuring a fan suction port corresponding to the air volume of a fan and a reference differential pressure immediately before an impeller. Ventilation equipment.