JPS6217306Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a vehicle air conditioner, and particularly to the relationship between compressor operation and engine rotational speed.

Conventionally, vehicle air conditioning systems have mainly consisted of a compressor.In order to compensate for the load placed on the engine when the compressor operates when the engine is idling, and to ensure cooling performance during idling, the The engine speed is increased. FIG. 1 shows an example of an air conditioner that performs such control. In the figure, reference numeral 1 denotes a thermosensor that is activated by the output signal of a temperature detector (not shown) that detects the temperature of the evaporator, and controls the control electromagnetic clutch 3 of the compressor 2 on and off.
The off level of this thermosensor 1 is set, for example, to the freezing temperature of the evaporator, and has the function of turning off the compressor 2 when the temperature of the evaporator drops just before freezing. In addition, as the cabin temperature setting device is set to a high temperature side, this off level is gradually raised, and even if the temperature of the evaporator does not reach a low temperature, the compressor 2 is turned off to save power. It has been proposed (unknown) by the applicant. One end of this thermosensor 1 is connected to a power source via a cooler switch 4, and the other end is connected to an electromagnetic clutch 3 and also to a transducer 6 for adjusting the negative pressure from a negative pressure source 5. The negative pressure from the negative pressure source 5 is transferred to the transducer 6.
A rod 8 of the actuator 7 adjusts the amount of mixed gas taken into the engine. The negative pressure source 5, transducer 6, actuator 7, etc. constitute an idling speed increasing mechanism.

In the above configuration, when the thermosensor 1 turns on when the engine is idling, the compressor 2
is turned on, the electromagnetic solenoid 9 of the transducer 6 is turned on, the valve 10 is opened, and the rod 8 is attracted against the spring 11, thereby controlling the butterfly 14 which adjusts the amount of mixed gas sucked into the engine. is opened slightly, increasing the engine speed.

However, with this configuration, the butterfly is slightly opened when the compressor is turned on even when the vehicle is decelerating, resulting in increased gasoline consumption and poor engine braking effectiveness.

Therefore, the inventor of the present invention has proposed a vehicle air conditioner shown in FIG. In this figure, the same parts as in FIG. 1 are designated by the same reference numerals. In this case, a pressure detection switch 12 is inserted between the thermosensor 1 and the transducer 6. This pressure detection switch 12 is connected to the intake pipe 1 as shown in FIG.
Butterfly 14 for mixed gas adjustment provided in 3
As shown in FIG. 4, when the negative pressure in the intake pipe 13 is higher than the set level 15, it is turned on, and when it is lower, it is turned off. The setting level 15 is set between the negative pressure 16 during idling and the negative pressure 17 for deceleration, and thereby the switch 1
2, the negative pressure in the intake pipe 13 is turned on during idling and acceleration, and turned off during deceleration, so even if the thermosensor 1 is activated during deceleration, the transducer 6 is not activated and the engine speed does not increase. This makes it possible to achieve low combustion, improve the effectiveness of engine braking, and make it easier for inertial energy during deceleration to be regenerated into the engine, making it easier for the compressor 2 to utilize the inertial energy.

However, according to this vehicle air conditioner, the pressure detection switch 12 detects the negative pressure inside the intake pipe 13.
Since the structure is such that the idling speed increasing mechanism consisting of the transducer 6 and the like is controlled, the structure is complicated, and the pressure inside the intake pipe 13 tends to fluctuate, making the operation unstable.

Therefore, the object of the present invention is to connect the electromagnetic clutch 3 between the power supply and the electromagnetic clutch 3, and turn off the electromagnetic clutch 3 by turning it off when the temperature detected by the temperature detector of the evaporator drops to a predetermined value. A thermosensor 1 connected to this thermosensor 1,
An idling speed increasing mechanism that operates when the thermosensor 1 is turned on to increase the engine speed; a brake switch 21 that is connected to the brake lamp 22 of the vehicle and turns on when the brake is applied; and a brake operation switch 18 connected between the thermosensor and the idling speed increasing mechanism, and turning off when the brake switch 21 is turned on to cut off the signal from the thermosensor 1 to the idling speed increasing mechanism. The above-mentioned drawbacks are eliminated by disconnecting the idling speed increasing mechanism during deceleration, and will be described in detail below using examples.

FIG. 5 is a circuit diagram showing an embodiment of the vehicle air conditioner according to the present invention, and the same parts as in FIG. 2 are designated by the same reference numerals. In this case, thermosensor 1
A brake actuation switch 18 is connected between the transducer 6 and the transducer 6 . The switch 18 consists of a normally closed contact 19 and a relay 20. The relay 20 is connected between the brake switch 21 and the brake lamp 22, and is energized when the brake switch 21 is turned on, turning off the contact 19. shall be. As a result, by stepping on the brake pedal during deceleration, the brake switch 21 is turned on and the contact point 19 is turned off, which prevents the engine from accelerating even if the compressor 2 is turned on, resulting in lower fuel consumption. Improves the effectiveness of engine braking.

As explained above, according to the present invention, in a vehicle air conditioning system, the compressor is turned off when the temperature of the evaporator drops to a predetermined level, and the engine speed is increased at this time.
Since the increase in engine speed is suppressed by the detection unit that detects deceleration of the vehicle, it is possible to achieve low fuel consumption and to make the engine brake work effectively. Moreover, the structure is simple because the deceleration of the vehicle is detected based on the brake switch and the increase in engine speed is suppressed.
Operation becomes reliable.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an example of a conventional vehicle air conditioner, and FIGS. 2 to 4 are circuit diagrams, simplified configuration diagrams, and diagrams showing an example of a vehicle air conditioner proposed by the present inventor. The characteristic diagram and FIG. 5 are circuit diagrams showing an embodiment of the vehicle air conditioner according to the present invention. 1... Thermosensor, 2... Compressor, 3
... Electromagnetic clutch, 5 ... Negative pressure source, 6 ... Transducer, 7 ... Actuator, 12 ... Pressure detection switch, 18 ... Brake operation switch.

Claims (1)

[Scope of utility model registration request] A thermosensor 1 that is connected between a power source and an electromagnetic clutch 3 and that turns off and deenergizes the electromagnetic clutch 3 when the temperature detected by a temperature detector of the evaporator drops to a predetermined value; and this thermosensor. 1, an idling speed increasing mechanism operates when the thermosensor 1 is turned on to increase the engine speed, and a brake lamp 22 of the vehicle.
A brake switch 21 is connected to the brake switch 21 and is turned on when the brake is applied, and a brake switch 21 is connected between the thermosensor and the idling speed increase mechanism and is turned off when the brake switch 21 is turned on, causing the thermosensor 1 to turn on the idling speed increase mechanism. 1. An air conditioner for a vehicle, comprising a brake operation switch 18 that cuts off a signal to a speed mechanism.