JPS59134009A - Air conditioner for car - Google Patents

Abstract

PURPOSE:To improve the fuel consumption and cooling efficiency by constituting so that a compressor is stopped for a fixed time when the difference between the detected car room temperature and a preset temperature is at a predetermined value or less and the engine suction negative pressure is at a predetermined value or less. CONSTITUTION:The difference TR-TS between the detected temperature TR of a room temperature sensor 2 and a preset temperature TS is calculated with a control circuit 4 and compared with a predetermined value. On the other hand, the engine suction negative pressure P is extracted from a detector 1 to be compared with a predetermined value. When the temperature TR-TS and the suction negative pressure P become preset values or less respectively, a stop signal S is fed to a compressor 5 to stop it for a fixed time. According to this constitution, the fuel consumption and cooling efficiency can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a vehicle that improves fuel efficiency and cooling efficiency in a device that stops the operation of a compressor when the engine intake negative pressure becomes smaller than a certain value while driving. related to air conditioning equipment.

Many modern vehicles are equipped with near conditioners (so-called air conditioners) that dehumidify and adjust room temperature to make the interior of the vehicle more comfortable. Vehicle rain air conditioning systems use the power of the engine to drive the compressor, and when the refrigerant compressed by this compressor expands, it takes heat from the surroundings to cool the air. The air is heated using the air, and the ratio of cooling and heating is appropriately selected to produce cold air at a desired temperature or (1-1 warm air) and blow into the passenger compartment to adjust the room temperature.

By the way, recently, reducing engine load has been considered from the perspective of improving fuel efficiency, and air conditioning systems also utilize the fact that when the accelerator pedal is pressed during vehicle acceleration, the engine intake negative pressure decreases. When the suction negative pressure becomes smaller than a certain value in order to reduce the engine load, this is detected and the operation of the compressor is stopped for a certain period of time (for example, 3 seconds) as shown in FIG.

Controlling the compressor operation according to the suction negative pressure in this way can reduce the engine load during acceleration and improve the melting cost, but the compressor may stop in the middle of the cooling mode. This poses a problem in that the operating rate of the compressor decreases, the cooling effect decreases, and it takes a long time to reach the target temperature.

The present invention has been made in consideration of the above-mentioned points VC, and is intended to improve fuel efficiency and cooling efficiency in a device that stops driving a compressor when the engine intake negative pressure becomes smaller than a certain value. The compressor is configured to stop driving when the temperature difference S between the cabin humidity and the set humidity is less than a predetermined value and the engine suction negative pressure is less than a certain value.

The present invention will be explained and explained below based on the drawings.

FIG. 2 is a block diagram showing an embodiment of the air conditioner according to the present invention, in which 1 is a suction negative pressure detector that detects the suction negative pressure of the engine, 2 is a room temperature sensor that detects the humidity inside the vehicle, and 3 is a block diagram showing an embodiment of the air conditioner according to the present invention.
is a temperature setting device that sets a target temperature in the vehicle interior, and is a control circuit that controls the operation of the compressor 5 based on signals from the four-digit suction negative pressure detector 1, the room temperature sensor 2, and the temperature setting device 3.

In the air conditioner having the above configuration, if the vehicle interior temperature currently detected by the room temperature sensor 2K is TR% and the set humidity is Ts, then the heat exchanger temperature (TRTS) changes as shown in FIG. 3(A). On the other hand, it is assumed that the engine suction negative pressure P changes as shown in FIG. The control circuit 4 has a temperature difference (TR
Calculate the temperature difference, for example, 4C or less, and make sure that the suction negative pressure P or a predetermined pressure (for example, -100m+) is calculated.
Hg) When it becomes small, output a stop signal S for the compressor 5. The compressor 5 stops its operation in response to this stop signal S (see FIG. 3(c)).

As explained above, in the present invention, when the temperature difference between the vehicle interior temperature and the set temperature is less than a predetermined value and the engine intake negative pressure is less than a predetermined value, the operation of the compressor is stopped for a certain period of time. Therefore, it is possible to improve fuel efficiency without reducing the cooling effect when the engine accelerates.

[Brief explanation of drawings]

Fig. 1 is a diagram showing changes in engine intake negative pressure and the operating state of the compressor, Fig. 2 is a block diagram of the air conditioner according to the present invention, and Fig. 3 explains the operation of the air conditioner according to the present invention. In the time chart for
-y Displays the operating status of the front panel. 1... Inhalation negative pressure detector, 2... Room temperature sensor, 3...
Temperature setting device 1, 1... Control circuit, 5... Comprennosa patent applicant Nissan Motor Co., Ltd. agent Patent attorney Hiroshi Suzuki Figure 1 Figure 2 Figure 3 Figure 43-

Claims (1)

[Claims] A suction negative pressure detector that detects the engine's suction negative pressure, a room temperature sensor that detects the temperature inside the vehicle, a temperature setting device, and the temperature set by the vehicle interior temperature detected by the room temperature sensor and the flow # setting device. If the temperature difference between the set temperature and the set temperature is less than the specified value,
and a compressor drive control circuit that outputs a compressor stop signal for a certain period of time when the suction negative pressure detected by the suction negative pressure detector becomes smaller than a predetermined value. .