JPS5878823A - Method of controlling compressor for cooling in vehicle - Google Patents

Abstract

PURPOSE:To effectively utilize the deceleration energy of a vehicle for cooling therein, by surely detecting the deceleration of the vehicle on the basis of the detected values of the vehicle speed and the negative pressure of an intake manifold to drive a compressor for the cooling. CONSTITUTION:The negative pressure of a manifold 14 is found out by a negative pressure detector 9 made of a diaphragm 10. The speed of a vehicle is found out in terms of the output signal of a speedometer. It is first judged whether the vehicle speed is higher than a set level or not. When the speed is not higher than the set level, as during the stoppage of the vehicle, a compressor 1 is put in operation. When the speed is higher than the set level, it is judged whether the negative pressure is higher than a set level or not. When the negative pressure is higher than the set level, namely, the vehicle is being decelerated, the compressor 1 is put in operation. When the negative pressure is not higher than the set level, namely, in the high load state such as acceleration, rapid movement and uphill movement, the compressor 1 is put out of operation.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling a compressor for cooling a vehicle, and particularly to a method for controlling a compressor for cooling the interior of a vehicle or a freezer, and in particular to a method for controlling a compressor according to the load state of the vehicle.

Conventionally, a system as shown in FIG. 1 has been proposed that detects the load condition of a vehicle and controls a compressor. In the same figure, 1 is the magnetic clutch 2
A power supply 4 is connected to the electromagnetic coil 3 that constitutes the magnetic clutch 2, and a cooling switch 5. Defrost 2 switch 6. It is connected via a magnetic clutch control relay 7. The defrost switch 6 detects the temperature on or near the surface of the evaporator that is cooled by the compressor 1, and when the temperature of the evaporator reaches a temperature just before freezing, it is turned off and prevents the coil 30 from being energized. This is to protect the property. The above relay 7 has a relay coil 7L and a coil 7L.
When the coil 7A is excited, the contact 7c is turned on. The coil 7t is energized or deenergized by the negative pressure detection switch 8, and the movable contact 8m of this switch 8 is connected to the negative pressure detector 9vf-
It is interlocked with the constituent diaphragm 1o via an actuating rod 11. The negative pressure detector 9 is divided by a diaphragm 10 into a negative pressure chamber 12m and an atmospheric pressure chamber 13m.
Intake manifold 14 via 2a negative pressure Dunno and 21
It is connected to.

Further, the negative pressure detection switch 8 includes a negative pressure detection switch 15.
are connected in parallel, and the movable contact 15m of this switch 15 connects to the diaphragm 18 of the negative pressure detector 17 via the actuating rod 16.
The negative pressure chamber 12b of the negative pressure detector 17 is connected to the carburetor 20 via the Dunn's arm 19. still,
The operating rods 11 and 16 are pressed by springs 11a and 16a so that the movable contacts 8m+15mi are always turned off against the fixed contacts.

In such a configuration, when the automobile is idling, the negative pressure in the intake manifold 14 is the idling negative pressure, so the movable contact 8m of the negative pressure detection switch 8 is turned off by the setting force of the spring l1m, and Also, since the negative pressure of the carburetor 20 supplied to the damper 19 side is close to atmospheric pressure, the contact 15m of the negative pressure detection switch 15 is turned off by the setting force of the spring 16a, and therefore the link coil 7t of the relay 7 is deenergized. In this state, no output from the power source 4 is supplied to the electromagnetic clutch 2, and the compressor 1 is not driven. Next, when the automobile is traveling normally, the negative pressure in the intake manifold 14 does not reach the set value of the negative pressure detection switch 8, and the negative pressure detection switch 8 is turned off. Further, the negative pressure of the carburetor 20 reaches a negative pressure that activates the negative pressure detection switch 15, and the negative pressure detection switch 15 is turned on and the compressor 1 is driven. The car accelerates.

When operating under a high load condition such as when climbing a hill, the negative pressure in the intake manifold 14 and the carburetor 20 are both close to atmospheric pressure, and the negative pressure detection switch 8,150 does not reach the set value and both turn off. is in a stopped state. When the car is decelerating, the negative pressure in the carburetor 20 is close to atmospheric pressure and the negative pressure detection switch 15 is turned off, but the negative pressure in the intake manifold increases and the negative pressure detection switch 8 is turned off.
When the set value is reached, the negative pressure detection switch 8 is turned on and the pressure sensor l is driven.

However, the above-mentioned conventional control system has a drawback in that there is little difference in the intake manifold negative pressure between idling and deceleration, and it is very difficult to detect the difference in negative pressure.

An object of the present invention is to perform reliable deceleration detection by detecting the running state of the vehicle based on the negative pressure of the intake manifold and the vehicle speed, and to effectively utilize the deceleration energy of the vehicle as energy for cooling. The intake manifold negative pressure is detected, and when the vehicle speed is above the set speed and the above negative pressure is below the set value (2), the compressor is stopped, and when the vehicle speed is below the set value or when the vehicle speed is above the set value and The above objective is achieved by driving the compressor when the negative pressure is above a set value.

Examples of the present invention will be described in detail below.

FIG. 2 is a flowchart showing an embodiment of the method for controlling a vehicle cooling compressor according to the present invention. As is clear from the figure, in the present invention, manifold negative pressure is detected by a dial slam or the like, and the vehicle speed is increased. Detected by meter output signal. First, it is determined whether the vehicle speed is higher than the set speed or not, and when the vehicle speed is not higher than the set speed, for example, when the vehicle is stopped, the compressor is turned on. When the vehicle speed is higher than or equal to the set speed, it is determined whether the negative pressure is greater than or equal to the set value. If the negative pressure is greater than the set value, that is, the vehicle is decelerating, the compressor is turned on and the negative pressure is If the value is below the set value, in other words, the vehicle accelerates.

This turns off the compressor during high load conditions such as high speed driving or pitching.

Therefore, according to the present invention, when the vehicle speed is higher than the set speed and the negative pressure is higher than the set value, it is in a deceleration state, so by turning on the compressor at this time, the deceleration energy of the vehicle can be used to drive the compressor. At this time, the cooling cycle can be fully activated.
Cooling air can be stored in the passenger compartment, increasing energy efficiency. In this embodiment, the compressor is turned on when the vehicle is idling and stopped, but in this case, a means is provided to activate the fast idling mechanism to increase the engine speed.

If added, the load on the engine can be reduced and the lack of cooling can be compensated for. However, when the compressor is turned off during deceleration, the speed increasing operation of the fast idling mechanism is stopped.

Further, the following points can be mentioned as other effects of the present invention.

In other words, when controlling the compressor by determining whether the vehicle is idling or decelerating when the vehicle is stopped by detecting only negative pressure, there may be a slight difference in the magnitude of the negative pressure between idling and decelerating. Therefore, it is necessary to increase the detection accuracy of the negative pressure detector, which results in the need for a negative pressure detector with a complicated configuration, which increases the cost and requires precision adjustment when applied to vehicles of various types. Although it is complicated, according to the present invention, the idling state and the deceleration state are detected depending on the vehicle speed and the manifold negative pressure, so it is possible to distinguish between normal driving and deceleration depending on the negative pressure state. Since the difference in negative pressure is large, its detection is reliable.
Does not require a negative pressure detector with high detection accuracy as in the past,
It is also possible to adapt to changes in vehicle models.

In addition, in the present invention, when special deceleration is performed for a long time when traveling downhill or on a long slope, the compressor is controlled by a switch that detects the temperature on or near the surface of the evaporator. [To prevent the evaporator from freezing], and when driving up a long slope, a timer can be used to control the compressor so that it is turned on after a certain period of time has passed since the compressor stopped. It can be used freely, and the problem of the temperature inside the vehicle rising to an uncomfortable temperature due to the compressor being turned off can be solved.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an example of a conventional method for controlling a vehicle cooling compressor, and FIG. 2 is a flowchart showing an example of a method for controlling a vehicle cooling compressor according to the present invention. 1...Compressor, 2...Magnetic clutch,
9.17... Negative pressure detector, 14... Manifold, 20... Vaporizer. Patent applicant: Diesel Kiki Co., Ltd. Agent Patent attorney: Jun Miyazono - Procedural amendment (method) 1. Display of the case 1982 Patent Application No. 177897 2 Title of invention Control method for vehicle cooling compressor 3
, those who make corrections and above

Claims (1)

[Claims] The vehicle speed and manifold negative pressure are detected, and the compressor is stopped when the vehicle speed is above the set speed and the above negative pressure is below the set value, and when the vehicle speed is below the set speed or when the vehicle speed is above the set speed and the above negative pressure is stopped. A method of controlling a compressor for cooling a vehicle, characterized in that the compressor is driven when the pressure is above a set value.