JPS6310003B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for detecting the temperature inside a vehicle, which is used, for example, in a vehicle air conditioner, in which heat around a tube in which a temperature sensor is installed is transmitted to the sensor via a lead wire. The present invention relates to a vehicle interior temperature detection device that suppresses the influence.

1 to 3 show a vehicle air conditioner to which a conventional vehicle interior temperature detection device is applied. In FIG. 1, 1 is an outside air inlet, 3 is an intake door, 5 is a blower fan, 7 is an evaporator that cools and dehumidifies the air sent from the blower fan 5, and 9 is an air mix door that controls the amount of cooled and dehumidified air passing through the heater core 11. , 13 is a temperature-controlled air outlet into the vehicle interior, and 15 is an outside air sensor 15.
a and a vehicle room temperature sensor 15b (for example, a thermistor), 17 is a variable resistor for setting the vehicle interior temperature, and 19 is a resistance value change of the temperature detector 15 when the outside air temperature and the vehicle interior temperature change. 23 is an amplifier that outputs to the converter 21 a signal of a predetermined level determined by the potential at point P determined by the voltage drop due to the resistance value corresponding to the set temperature of the variable resistor 17; This is a drive unit that adjusts the opening degree of the air mix door according to the output signal.

FIG. 2 shows a schematic cross-sectional view of the instrument panel 25. Reference numeral 27 indicates a vehicle interior and an air conditioner in which a vehicle room temperature sensor 15b is provided and air is taken into the vehicle by driving an aspirator 28 (details are shown in FIG. 3). A pipe 29 that communicates with the air conditioning duct 26 is a front window glass, and the aspirator 28 is provided in a pipe 27 that communicates the air conditioning duct 26 with the interior of the vehicle.

FIG. 3 is an enlarged view of the periphery of the tube 27, and the vehicle room temperature sensor 15b is arranged vertically in the interior space of the tube 27. Note that 31 is a lead wire of the sensor 15b placed in the instrument panel, and 33 is a coupler.

The reason why the pipe 27 and the aspirator 28 that communicate the interior of the vehicle and the air conditioning duct 26 are provided in the instrument panel is as follows. In other words, to accurately detect the temperature inside the vehicle, it would be sufficient to install the temperature sensor vertically in the center of the vehicle (for example, in the center of the roof), but for reasons such as detracting from aesthetics, it is necessary to install the temperature sensor in the instrument panel. It is conceivable to install a temperature sensor in the However, if the temperature sensor is simply provided within the instrument, there is a risk that the temperature sensor itself will be affected by heat due to solar radiation from the front window glass, external heat, etc., and accurate temperature detection may not be possible. For this reason, as described above, a method is adopted in which a pipe 27 is formed in the instrument that communicates between the air conditioning duct 26 and the vehicle interior, and the interior air is drawn through the aspirator 28 to detect the vehicle interior temperature. .

The operation is based on the interior temperature detected by the vehicle room temperature sensor 15b based on the interior air taken into the pipe 27, the outside temperature detected by the outside air sensor 15a, and the temperature set by the variable resistor 17. The temperature of the air from the air outlet 13 is adjusted according to the difference by controlling the opening degree of the air mix door 9, thereby bringing the temperature inside the vehicle to the set temperature.

In the vehicle air conditioner with the above configuration,
Based on the detection results of the vehicle interior temperature and outside air temperature, it is possible to perform appropriate control to bring the vehicle interior temperature to a desired set temperature. Therefore, in order to do this, it is necessary to accurately measure the temperature inside the vehicle and the temperature outside the vehicle.For the reasons mentioned above, conventional devices measure the temperature inside the vehicle from the interior air taken into the pipe formed in the instrument panel. Detecting indoor temperature. However, the temperature inside the instrument panel generally tends to be higher at the beginning of cool-down and lower at the beginning of warm-up (about 2 degrees Celsius difference) compared to the temperature inside the vehicle. The lead wires of the vehicle room temperature sensor that are connected to the vehicle may become warmer or colder due to the influence of this heat, so the vehicle room temperature sensor may not be able to perform accurate detection due to heat conduction from the lead wires.

An easy way to solve the above problem would be to eliminate the above-mentioned tendency by blowing warm air into the instrument panel, but this would require a new blower device, which would increase costs. Furthermore, there is a problem in that the hot air or the like may affect equipment installed within the panel.

The present invention has been made in view of the above, and includes a device for introducing vehicle interior air into a tube having an intake port inside the vehicle interior and detecting its temperature. In order to suppress the influence of conduction to the inside of the pipe, the temperature sensor is connected to the inside of the pipe by a lead wire that is disposed inside the pipe via a support means and extends outside the pipe, and releases conductive heat into the pipe. It is designed to be held in space.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 4 shows an embodiment of the present invention, the feature of which is that a part of the lead wire 31 is supported and fixed in the space inside the pipe 27' which communicates the vehicle interior and the air conditioning duct 26 by means 35. The reason is that the support is fixed. The length of the lead wire inserted into the tube 27' is as follows:
It is sufficient that the amount of heat conduction from the lead wires installed in the instrument panel 25 can be offset.

The support fixing means 35 constitutes a support means, and is formed in a cylindrical shape as shown in FIG. 5, and has an insertion hole 35a for the vehicle room temperature sensor 15b in the center.
is provided, and when inserted into the tube 27', it is locked by a stopper 37 formed on the inner surface of the tube.

FIG. 6 shows another embodiment of the present invention, the feature of which is that a lead wire 31 is placed inside the tube 27, for example, in a spiral shape, and a clip 3 constituting the support means is used.
This is because it was installed and fixed in Step 4. 4 and 3 indicate the same components.

FIG. 7 is a characteristic diagram of changes in the resistance value of the vehicle room temperature sensor 15b (a thermistor with reverse characteristics) with respect to the vehicle interior temperature T. In FIG. 7, a characteristic curve A shows a case where the instrument panel internal temperature T _P and a vehicle interior temperature T are equal, a characteristic curve B shows a case where T _P >T, and a characteristic curve C shows a case where T _P <T. That is, the resistance value R of the vehicle room temperature sensor 15b in the conventional vehicle interior temperature detection device should originally be Ra [KΩ] when the vehicle interior temperature is _T1 , but due to heat conduction from the lead wire 31, the resistance value R of the vehicle room temperature sensor 15b is Under the condition of T _P > T, Rb [KΩ], and under the condition of T _P <T, Rc [KΩ], and the vehicle room temperature sensor 15b is set to (T ₂ -
T ₁ ) and (T ₁ − _{T 3} ) were detected as incorrect values.
In the embodiment of the present invention shown in FIGS. 4 and 6, the temperature T _P inside the instrument panel does not affect the vehicle room temperature sensor 15b, so the characteristic curve A is maintained regardless of the temperature T _P. Accurate vehicle interior temperature T can be detected based on the temperature.

Figure 8 shows the time t due to the operation of the vehicle air conditioner.
FIG. In the air conditioner to which a conventional vehicle interior temperature detection device is applied, when control is performed based on the falsely detected vehicle interior temperature, the vehicle interior temperature T
overshot the set temperature _T0 , and it took some time to set the vehicle interior temperature T to the set temperature _T0 . In the vehicle air conditioner to which the embodiment shown in FIG. 4 or 6 is applied, as explained in FIG. 7, the vehicle interior temperature T can always be accurately measured. The time it takes to set the temperature T to the set temperature T ₀ is shorter than before, allowing for better vehicle room temperature control.

Although the above embodiment describes a case in which a duct that communicates with the interior space of the vehicle is provided in the instrument panel to suck in air from the vehicle interior, it is also possible to provide a duct in the rear persiel to suck in air from the vehicle interior. Of course, there is no problem, and it goes without saying that there is no problem with it, as long as it can accommodate a duct that communicates with the passenger compartment other than the rear parsiel.

As explained above, according to the present invention, in a device for introducing vehicle interior air into a pipe having an intake port in the vehicle interior and detecting its temperature, a temperature sensor for detecting temperature is provided with a support means in the pipe. Since the conductive heat from the lead wire disposed through the tube and extending outside the tube is retained in the inner space of the tube by the lead wire which releases into the tube, heat around the tube is not conducted through the lead wire. This does not affect the temperature sensor, and it is possible to prevent the temperature sensor from erroneously detecting the temperature inside the vehicle.

[Brief explanation of the drawing]

Figures 1 to 3 show a vehicle air conditioner to which a conventional vehicle interior temperature detection device is applied. Figure 1 is a schematic diagram of the air conditioner, and Figure 2 is a schematic cross-sectional diagram of the interior of the instrument panel. , FIG. 3 is an enlarged view of a pipe communicating the vehicle interior and an air conditioning duct, FIG. 4 is an embodiment of the present invention, FIG. 5 is a perspective view of the supporting and fixing means, and FIG. 6 is another embodiment of the present invention. For example, Fig. 7 is a characteristic diagram of the resistance value change of the vehicle room temperature sensor with respect to the vehicle interior temperature T, and Fig. 8 is a graph showing the change in resistance value of the vehicle room temperature sensor with respect to the vehicle interior temperature T.
FIG. Explanation of symbols representing main parts of the figure, 25...
Instrument panel, 27...tube, 15b...
... Vehicle room temperature sensor 3, 1 ... Lead wire, 35 ... Supporting and fixing means.

Claims (1)

[Claims] 1. In a device that detects the temperature of air inside a vehicle by introducing it into a tube having an intake port inside the vehicle, a lead wire extending outside the tube and a conduction wire disposed inside the tube are connected. A lead wire that emits heat into the tube, a support means that is inserted and fixed into the tube and supports the lead wire disposed within the tube, and a temperature sensor that is held in the inner space of the tube by the lead wire supported by the support means. A vehicle interior temperature detection device for a vehicle air conditioner, comprising: