JP2023071628A - Refrigeration cycle device for vehicle and on-vehicle apparatus control device - Google Patents

Abstract

To reduce a stop frequency of a compressor, and to smoothly re-drive the compressor.SOLUTION: A refrigeration cycle device comprises: a compressor 21 driven by a gasoline engine 2; a heat radiator 22 for heat-radiating a refrigerant discharged from the compressor 21; a decompressor 23 for decompressing the refrigerant which is heat-radiated by the heat radiator 22; an evaporator 123 for evaporating the refrigerant which is decompressed by the decompression part 23; a pressure equalization part 28 for equalizing pressure by making a suction side and a discharge side of the compressor 21 communicate with each other; a pressure equalization valve 26 for opening and closing the pressure equalization part 28; and a control part 40 for controlling a magnet clutch for intermitting a drive force transmitted to the compressor 21 from the gasoline engine 2 and the pressure equalization valve 26. When a brake pedal is pedaled in, and the negative pressure of the intake air of the gasoline engine 2 is lower than a prescribed value, the control part 40 controls the magnet clutch so that the drive force from the gasoline engine 2 is blocked, and the compressor 21 is stopped, and valve-opens the pressure equalization valve 26 so as to make the suction side and the discharge side of the compressor 21 communicate with each other.SELECTED DRAWING: Figure 4

Description

The present invention relates to a refrigerating cycle device used in a vehicle that runs on a gasoline engine, and an on-vehicle equipment control device that controls on-vehicle equipment mounted on a vehicle that runs on a gasoline engine.

Conventionally, the vehicular refrigeration cycle apparatus described in Patent Document 1 is mounted on a vehicle having a brake booster. The brake booster accumulates the negative pressure generated in the intake system of the gasoline engine of the vehicle as brake negative pressure, and is driven by the brake negative pressure to reduce the brake pedal operation force of the driver.

Here, the gasoline engine of the vehicle is subjected not only to the running load but also to the automatic transmission, the compressor, the alternator, and the like. When these loads increase while the vehicle's gasoline engine is idling, the idle speed control works to open the throttle valve so as to maintain the vehicle's gasoline engine speed, reducing the intake negative pressure. , the brake negative pressure also decreases.

In particular, in a vehicle such as a refrigerated vehicle, which has two refrigerating cycle devices, a refrigerating cycle device for air-conditioning the passenger compartment and a refrigerating cycle device for air-conditioning the luggage compartment, the compressor of the refrigerating cycle device for air-conditioning the passenger compartment and the refrigerating cycle device for air-conditioning the luggage compartment Since there are two compressors, the compressor of the cycle device, the load on the gasoline engine of the vehicle tends to be high. Therefore, the negative pressure of the intake air tends to decrease, and the negative pressure of the brake tends to decrease as well.

In this respect, the vehicular refrigerating cycle device described in Patent Document 1 stops the driving of the vehicular refrigerating cycle device when the brake negative pressure does not reach the value necessary to operate the brake booster. ing.

Specifically, the load on the vehicle engine is reduced by stopping the compressor driven by the gasoline engine of the vehicle, so the intake air amount of the gasoline engine of the vehicle decreases and the throttle valve is controlled to the closing side. . As a result, the negative pressure of the intake air increases, and the brake negative pressure required to drive the brake booster is ensured.

JP-A-2000-73810

However, in the conventional technology described above, when the brake negative pressure does not reach the value necessary to operate the brake booster, the compressor stops even if the brake pedal is not depressed, so a compressor (in-vehicle device) is required. It will stop more than that.

In addition, when the compressor is restarted after being stopped, the compressor may be restarted while the pressure inside the compressor is high. A large operating noise may be generated, or the magnetic clutch may slip, resulting in increased wear of the magnetic clutch.

SUMMARY OF THE INVENTION In view of the above problems, it is a primary object of the present invention to reduce the frequency of compressor stoppages and to facilitate re-driving of the compressor.

A second object of the present invention is to reduce the frequency of stoppages of in-vehicle equipment for ensuring brake negative pressure.

In order to achieve the first object, in the invention according to claim 1,
a compressor (21) driven by the gasoline engine (2) for sucking, compressing and discharging refrigerant;
a radiator (22) for dissipating heat from the refrigerant discharged from the compressor (21);
a decompression unit (23) for decompressing the refrigerant radiated by the radiator (22);
an evaporator (123) that evaporates the refrigerant decompressed by the decompression unit (23);
a pressure equalizing section (28) for equalizing the pressure by communicating the suction side and the discharge side of the compressor (21);
a pressure equalizing valve (26) for opening and closing the pressure equalizing section (28);
A control unit (40) that controls a magnetic clutch that interrupts driving force transmitted from the gasoline engine (2) to the compressor (21) and a pressure equalizing valve (26),
The control unit (40) has a brake pedal whose operating force is reduced by a brake booster that utilizes the negative pressure of the intake air of the gasoline engine (2), and is operated when the negative pressure of the intake air of the gasoline engine (2) is predetermined. If it is smaller than the value, engine load control is performed to control the magnetic clutch so that the driving force from the gasoline engine (2) is interrupted and the compressor (21) stops, and the suction side of the compressor (21) and the Pressure equalization control is performed to open the pressure equalizing valve (26) so as to communicate with the discharge side.

According to this, the compressor (21) is stopped when the brake pedal is stepped on and the intake negative pressure of the gasoline engine (2) is smaller than a predetermined value. Stopping the compressor (21) can be avoided.

Further, when the negative pressure of the intake air of the gasoline engine (2) is smaller than a predetermined value and the brake pedal is depressed, the equalizing valve (26) is opened, so the compressor (21) is stopped. The high pressure and low pressure of the refrigeration cycle can be equalized in between. Therefore, since the compressor (21) can be re-driven while the pressure in the compressor (21) is as low as possible, there is a large operating noise when the gasoline engine (2) and the compressor (21) are connected by the magnet clutch. Also, it is possible to prevent the magnetic clutch from slipping and wearing out.

From the above, it is possible to reduce the frequency of stopping the compressor (21) and facilitate the re-driving of the compressor (21).

According to the second aspect of the invention, in the vehicle refrigeration cycle apparatus according to the first aspect, the control unit (40) controls the stop time of the compressor (21) to be equal to or longer than the predetermined stop time (T1) in the engine load control. When it becomes, the magnetic clutch is controlled so that the driving force is transmitted to the compressor (21), and the engine load control ends. This makes it possible to re-drive the compressor (21) with simple control.

According to the invention of claim 3, in the vehicle refrigeration cycle apparatus of claim 1 or 2, the control unit (40) controls the valve opening time of the pressure equalizing valve (26) in the pressure equalizing control to the predetermined valve opening time ( When the pressure reaches T2) or more, the pressure equalizing valve (26) is closed to end the pressure equalizing control.

As a result, the pressure equalizing valve (26) can be closed by simple control to return the refrigeration cycle to normal operation.

According to a fourth aspect of the invention, in the vehicle refrigeration cycle apparatus according to the second aspect, the control unit (40) includes:
When the stop time of the compressor (21) in the engine load control reaches a predetermined stop time (T1) or more, the magnet clutch is controlled so that the driving force is transmitted to the compressor (21), and the engine load control is ended;
In the pressure equalization control, when the opening time of the equalizing valve (26) reaches a predetermined valve opening time (T2) longer than the predetermined stop time (T1), the equalizing valve (26) is closed to end the equalizing control. .

According to this, it is possible to prevent the pressure equalization control from ending before the compressor (21) is driven again, so that the high pressure and the low pressure of the refrigeration cycle can be equalized before the compressor (21) is driven again. can be done.

In the invention according to claim 5, in the vehicle refrigeration cycle apparatus according to any one of claims 1 to 4,
a bypass section (27) that bypasses the radiator (22) and the pressure reduction section (23) and guides the refrigerant discharged from the compressor (21) to the evaporator;
A bypass valve (25) for opening and closing the bypass section (27),
In the pressure equalization control, the control unit (40) opens the equalizing valve (26) and evaporates the refrigerant discharged from the compressor (21) by bypassing the radiator (22) and the pressure reducing unit (23). The bypass valve (25) is opened so as to lead to the vessel (123).

Thereby, the high pressure and the low pressure of the refrigeration cycle can be reliably equalized through the bypass portion (27).

According to a sixth aspect of the present invention, in the vehicle refrigeration cycle apparatus according to the fifth aspect, the control section (40) controls the valve opening time of the pressure equalizing valve (26) to the predetermined valve opening time (T2) in the pressure equalizing control. When the above is reached, the pressure equalizing valve (26) is closed and the bypass valve (25) is closed to end the pressure equalizing control.

As a result, the pressure equalizing valve (26) and the bypass valve (25) can be closed with simple control to return the refrigeration cycle to normal operation.

In order to achieve the second object, in the invention according to claim 7,
a compressor (21) driven by the gasoline engine (2) for sucking, compressing and discharging refrigerant;
a radiator (22) for dissipating heat from the refrigerant discharged from the compressor (21);
a decompression unit (23) for decompressing the refrigerant radiated by the radiator (22);
an evaporator (123) that evaporates the refrigerant decompressed by the decompression unit (23);
A control unit (40) that controls a magnetic clutch that interrupts driving force transmitted from the gasoline engine (2) to the compressor (21) and a pressure equalizing valve (26),
A control unit (40) increases the driving force when a brake pedal whose operating force is reduced by a brake booster that utilizes the negative pressure of the intake air of the gasoline engine (2) is depressed and the negative pressure is smaller than a predetermined value. is cut off to stop the compressor (21).

According to this, the compressor (21) is stopped when the brake pedal is stepped on and the intake negative pressure of the gasoline engine (2) is smaller than a predetermined value. Stopping the compressor (21) can be avoided. Therefore, it is possible to reduce the frequency of stopping the compressor (21), which is an in-vehicle device, in order to secure the brake negative pressure.

In order to achieve the second object, in the invention according to claim 8,
A load is applied to the gasoline engine (2) when a brake pedal whose operating force is reduced by a brake booster that utilizes the negative pressure of the intake air of the gasoline engine (2) is depressed and the negative pressure is smaller than a predetermined value. A control unit (40) for stopping the in-vehicle equipment (4, 21) is provided.

According to this, when the brake pedal is stepped on and the negative pressure of the intake of the gasoline engine (2) is smaller than a predetermined value, the in-vehicle device (4, 21) is stopped, so the brake pedal is not stepped on. It is possible to avoid stopping the in-vehicle equipment (4, 21) at times. Therefore, it is possible to reduce the frequency of stopping the in-vehicle devices (4, 21) for ensuring brake negative pressure.

According to the ninth aspect of the invention, in the on-vehicle device control apparatus of the eighth aspect, the on-vehicle device is driven by a gasoline engine (2), and a compressor ( 21) and
When the brake pedal is depressed and the negative pressure is smaller than a predetermined value, the control unit (40) controls the magnetic clutch that interrupts the driving force transmitted from the gasoline engine (2) to the compressor (21). The compressor (21) is stopped by controlling so that the driving force is cut off.

Therefore, it is possible to reduce the frequency of stopping the compressor (21) for securing the brake negative pressure.

It should be noted that the reference numerals in parentheses of each means described in this column and claims indicate the correspondence with specific means described in the embodiments described later.

1 is a schematic diagram showing a transportation vehicle in one embodiment; FIG. FIG. 2 is an overall configuration diagram of a luggage compartment air-conditioning/refrigerating cycle device used in the transport vehicle of FIG. 1; FIG. 3 is a block diagram showing an electronic control unit in the cargo room air-conditioning/refrigerating cycle apparatus of FIG. 2; FIG. 4 is a time chart illustrating control processing executed by the control device of FIG. 3; FIG.

An embodiment will be described below. FIG. 1 is a cross-sectional view schematically showing a transportation vehicle 1 on which a vehicle refrigeration cycle apparatus according to the present embodiment is mounted. In FIG. 1 , vertical and forward and backward arrows indicate the vertical and forward and backward directions of the transportation vehicle 1 .

The transportation vehicle 1 of this embodiment has a loading platform 11 on the rear side of a driver's cab 10 arranged at the frontmost portion of the vehicle. The loading platform 11 is formed in a box shape by a heat insulating material or the like. A cargo room 111 is formed in the cargo bed 11 .

A gasoline engine 2 that uses gasoline as fuel, an automatic transmission 3 that is a transmission mechanism, and an alternator 4 that is a generator are mounted in the lower part of the driver's cab 10 . The gasoline engine 2 is an internal combustion engine having a throttle valve that adjusts the amount of intake air. A vehicle is provided with a brake booster (not shown) that reduces an operation force when a driver depresses a brake pedal (not shown).

The brake booster utilizes the negative pressure of the intake air of the gasoline engine 2 to reduce the operating force when stepping on the brake pedal. A negative pressure passage extending from an intake pipe of the gasoline engine 2 is connected to the brake booster. The negative pressure passage extends from a portion of the intake pipe of the gasoline engine 2 downstream of the throttle valve. An intake pressure sensor 47 that detects the intake pressure of the gasoline engine 2 is arranged in the negative pressure passage.

Due to the negative pressure in the intake passage, air is sucked from inside the brake booster through the negative pressure passage, and the suction of the air creates a negative pressure in the brake booster. The brake booster is driven by the negative pressure that develops in the brake booster.

Although not shown, an opening for loading and unloading cargo and an opening/closing door for opening and closing the opening are provided on the side surface, the rear surface, and the like of the loading platform 11 . A cargo room air conditioning unit 12 is arranged in the cargo room 111 .

As indicated by arrows A<b>1 and A<b>2 in FIG. 1 , the luggage compartment air-conditioning unit 12 draws in air from the luggage compartment 111 to cool it and blow it out into the luggage compartment 111 . The temperature inside the luggage compartment 111 is adjusted by the air blown out from the luggage compartment air conditioning unit 12 .

A unit case 121 of the cargo room air conditioning unit 12 accommodates a first indoor fan 122, a first evaporator 123, and the like. The first indoor fan 122 is an electric fan driven by an electric motor.

By operating the first indoor fan 122, the air in the luggage compartment 111 is sucked into the unit case 121 and passed through the first evaporator 123 to be cooled. The air is blown out from 121 into the luggage compartment 111 . As a result, the air in the luggage compartment 111 is cooled and the luggage in the luggage compartment 111 is refrigerated or frozen.

A driver's cab air conditioning unit 13 is arranged in the driver's cab 10 . The driver's cab air conditioning unit 13 draws in the air in the driver's cab 10 or the outside air, cools or heats it, and blows it out into the driver's cab 10 . The temperature of the cab 10 is adjusted by the air blown out from the cab air conditioning unit 13 .

A unit case 131 of the driver's cab air conditioning unit 13 accommodates a second outdoor fan 132, a second evaporator 133, and the like. The second outdoor fan 132 is an electric fan driven by an electric motor.

By operating the second outdoor blower 132, the air in the operator's cab 10 or the outside air is sucked into the unit case 131, passes through the second evaporator 133, and is cooled.

The unit case 131 also accommodates a heater core (not shown), an air mix door (not shown), and the like. The heater core heats the air that has passed through the second evaporator 133 by exchanging heat with the engine cooling water. The air mix door adjusts the temperature of the air blown into the passenger compartment by adjusting the air volume ratio between the air flowing through the heater core and the air flowing bypassing the heater core.

The air that has passed through the second evaporator 133 and the heater core is blown out from the unit case 131 into the operator's cab 10 as indicated by an arrow A3 in FIG.

FIG. 2 is an overall configuration diagram of a cargo room air-conditioning/refrigerating cycle device 20 mounted on the transportation vehicle 1 of FIG. The luggage compartment air conditioning refrigeration cycle device 20 includes a first compressor 21 , a first condenser 22 , a first expansion valve 23 , a first evaporator 123 , a first bypass valve 25 and a first pressure equalizing valve 26 .

The first compressor 21 compresses and discharges the sucked refrigerant. For example, the first compressor 21 is arranged in the engine room of the vehicle.

For example, the first compressor 21 is an engine-driven compressor rotationally driven by the gasoline engine 2 via a first magnetic clutch (not shown). The first magnetic clutch is a driving force intermittence section that intermittently interrupts the driving force transmitted from the gasoline engine 2 to the first compressor 21 .

The cargo room air-conditioning refrigeration cycle device 20 employs an HFC-based refrigerant (specifically, R134a) as a refrigerant, and constitutes a subcritical refrigeration cycle in which the pressure of the refrigerant on the high-pressure side does not exceed the critical pressure of the refrigerant. . Refrigerant oil for lubricating the first compressor 21 is mixed in the refrigerant. Part of the refrigerating machine oil circulates through the refrigerant circuit of the refrigerating cycle device together with the refrigerant.

A first condenser 22 is connected to the discharge side of the first compressor 21 . The first condenser 22 heat-exchanges the high-pressure refrigerant (gas refrigerant) discharged from the first compressor 21 and the outside air (vehicle outside air) blown by a first outdoor fan (not shown) to produce a high-pressure refrigerant. is cooled and condensed. The first condenser 22 is a radiator that radiates heat from the refrigerant. The first outdoor fan is an electric fan driven by an electric motor.

A first expansion valve 23 is connected to the outlet side of the first condenser 22 . The first expansion valve 23 is a first decompression section that decompresses the high-pressure refrigerant (liquid refrigerant) condensed in the first condenser 22 .

For example, the first expansion valve 23 is a thermostatic expansion valve, and has a temperature sensing section that detects the degree of superheat of the refrigerant on the outlet side of the first evaporator 123 based on the temperature and pressure of the refrigerant on the outlet side of the first evaporator 123. Then, the throttle passage area is adjusted by a mechanical mechanism so that the degree of superheat of the refrigerant on the outlet side of the first evaporator 123 is within a predetermined range. The first expansion valve 23 may be an electric expansion valve that adjusts the throttle passage area by an electrical mechanism.

A first evaporator 123 is connected to the outlet side of the first expansion valve 23 . Low-pressure refrigerant (liquid refrigerant) decompressed by the first expansion valve 23 flows into the first evaporator 123, and this low-pressure refrigerant absorbs heat from the air blown by the first indoor fan 122 and evaporates to cool the air. do. The low-pressure refrigerant (gas refrigerant) evaporated in the first evaporator 123 is sucked into the first compressor 21 .

A first bypass flow path 27 is connected to the discharge side of the first compressor 21 and the inlet side of the first evaporator 123 . The first bypass flow path 27 is a bypass section through which the high-temperature refrigerant (hot gas) discharged from the first compressor 21 bypasses the first condenser 22 and the first expansion valve 23 . A first bypass valve 25 is arranged in the first bypass flow path 27 . The first bypass valve 25 is a bypass opening/closing unit that opens and closes the first bypass flow path 27 .

A first pressure equalizing flow path 28 is connected between the suction side of the first compressor 21 and the discharge side of the first compressor 21 . The first pressure equalizing flow path 28 is a pressure equalizing section that connects the suction side of the first compressor 21 and the discharge side of the first compressor 21 to equalize the pressure. A first pressure equalizing valve 26 is arranged in the first pressure equalizing flow path 28 . The first pressure equalizing valve 26 is a pressure equalizing channel opening/closing unit that opens and closes the first pressure equalizing channel 28 .

The first bypass valve 25 and the first pressure equalizing valve 26 are electromagnetic valves whose operations are controlled by control signals output from the control device 40 .

The configuration of the driver's compartment air-conditioning/refrigerating cycle apparatus 30 mounted on the transportation vehicle 1 of FIG. Therefore, reference numerals corresponding to the driver's compartment air-conditioning/refrigerating cycle device 30 are shown in parentheses in FIG.

The cab air conditioning refrigeration cycle device 30 includes a second compressor 31 , a second condenser 32 , a second expansion valve 33 , a second evaporator 133 , a second bypass valve 35 and a second pressure equalizing valve 36 .

The second compressor 31 compresses and discharges the sucked refrigerant. For example, the second compressor 31 is arranged in the engine room of the vehicle.

For example, the second compressor 31 is an engine-driven compressor rotationally driven by a vehicle engine (not shown) via a second magnetic clutch (not shown). The second magnetic clutch is a driving force intermittence section that intermittently interrupts the driving force transmitted from the gasoline engine 2 to the second compressor 31 .

The cab air conditioning refrigeration cycle device 30 employs an HFC refrigerant (specifically, R134a) as a refrigerant, and constitutes a subcritical refrigeration cycle in which the pressure of the refrigerant on the high-pressure side does not exceed the critical pressure of the refrigerant. . Refrigerant oil for lubricating the second compressor 31 is mixed in the refrigerant. Part of the refrigerating machine oil circulates through the refrigerant circuit of the refrigerating cycle device together with the refrigerant.

A second condenser 32 is connected to the discharge side of the second compressor 31 . The second condenser 32 heat-exchanges the high-pressure refrigerant (gas refrigerant) discharged from the second compressor 31 and the outside air (vehicle outside air) blown by a second outdoor fan (not shown) to produce a high-pressure refrigerant. is cooled and condensed. The second condenser 32 is a radiator that radiates heat from the refrigerant. The second outdoor fan is an electric fan driven by an electric motor.

A second expansion valve 33 is connected to the outlet side of the second condenser 32 . The second expansion valve 33 is a second decompression section that decompresses the high-pressure refrigerant (liquid refrigerant) condensed in the second condenser 32 .

For example, the second expansion valve 33 is a thermostatic expansion valve, and has a temperature sensing part that detects the degree of superheat of the refrigerant on the outlet side of the second evaporator 133 based on the temperature and pressure of the refrigerant on the outlet side of the second evaporator 133. Then, the throttle passage area is adjusted by a mechanical mechanism so that the degree of superheat of the refrigerant on the outlet side of the second evaporator 133 is within a predetermined range. The second expansion valve 33 may be an electric expansion valve that adjusts the throttle passage area by an electrical mechanism.

A second evaporator 133 is connected to the outlet side of the second expansion valve 33 . Low-pressure refrigerant (liquid refrigerant) decompressed by the second expansion valve 33 flows into the second evaporator 133, and this low-pressure refrigerant absorbs heat from the air blown by the second outdoor fan 132 and evaporates to cool the air. do. The low-pressure refrigerant (gas refrigerant) evaporated in the second evaporator 133 is sucked into the second compressor 31 .

A second bypass flow path 37 is connected between the discharge side of the second compressor 31 and the inlet side of the second evaporator 133 . The second bypass flow path 37 is a bypass portion through which the high-temperature refrigerant (hot gas) discharged from the second compressor 31 bypasses the second condenser 32 and the second expansion valve 33 . A second bypass valve 35 is arranged in the second bypass flow path 37 . The second bypass valve 35 is a bypass opening/closing unit that opens and closes the second bypass flow path 37 .

A second pressure equalizing flow path 38 is connected to the suction side of the second compressor 31 and the discharge side of the second compressor 31 . The second pressure equalizing flow path 38 is a pressure equalizing section that connects the suction side of the second compressor 31 and the discharge side of the second compressor 31 to equalize the pressure. A second pressure equalizing valve 36 is arranged in the second pressure equalizing flow path 38 . The second pressure equalizing valve 36 is a pressure equalizing channel opening/closing unit that opens and closes the second pressure equalizing channel 38 .

The second bypass valve 35 and the second pressure equalizing valve 36 are electromagnetic valves whose operations are controlled by control signals output from the control device 40 .

The control device 40 is composed of a well-known microcomputer comprising a CPU, ROM, RAM, etc., and its peripheral circuits, and performs various calculations and processes based on control programs stored in the ROM.

The control device 40 controls the first indoor fan 122, the first outdoor fan, the first compressor 21, the first bypass valve 25, the first pressure equalizing valve 26, the second outdoor fan 132, and the second outdoor fan connected to the output side. , the second compressor 31, the second bypass valve 35, the second pressure equalizing valve 36, and the like. The control device 40 constitutes an in-vehicle equipment control device that controls in-vehicle equipment such as the first compressor 21 and the second compressor 31 .

As shown in FIG. 3, various control sensor groups and various control switch groups are connected to the input side of the control device 40 . Various control sensors include a luggage compartment temperature sensor 41, a passenger compartment temperature sensor 42, an outside air temperature sensor 43, a solar radiation sensor 44, a first evaporator temperature sensor 45, a second evaporator temperature sensor 46, and an intake pressure sensor 47. etc. Various control switch groups include a brake switch 48 and the like.

The luggage compartment temperature sensor 41 detects the temperature inside the luggage compartment 111 . A vehicle interior temperature sensor 42 detects the temperature in the vehicle interior. An outside air temperature sensor 43 detects outside air temperature. A solar radiation sensor 44 detects the amount of solar radiation in the passenger compartment.

The first evaporator temperature sensor 45 is an evaporator temperature detector that detects the refrigerant evaporation temperature (first evaporator temperature) in the first evaporator 123 . The first evaporator temperature sensor 45 detects the temperature of the heat exchange fins of the first evaporator 123 and the temperature of the refrigerant on the outlet side of the first evaporator 123 .

The second evaporator temperature sensor 46 is an evaporator temperature detector that detects the refrigerant evaporation temperature (second evaporator temperature) in the second evaporator 133 . The second evaporator temperature sensor 46 detects the temperature of the heat exchange fins of the second evaporator 133 and the temperature of the refrigerant on the outlet side of the second evaporator 133 .

The intake pressure sensor 47 is an intake pressure detector that detects the intake pressure of the gasoline engine 2 . The brake switch 48 is a brake depression detector that detects depression of the brake pedal by the driver.

Various operation signals are input to the control device 40 from the operation panel 50 . The operation panel 50 is arranged near the instrument panel in the passenger compartment. The operation panel 50 includes a cargo room air conditioning operation switch for switching the operation/stop of the cargo room air conditioning/refrigerating cycle device 20 (specifically, the operation/stop of the first compressor 21), Driver's compartment air conditioning operation switch for switching between operation and stop (specifically, operation/stop of the second compressor 31), luggage compartment target temperature setting switch for setting the target temperature in the luggage compartment 111, target in the operator's compartment 10 A driver's cab target temperature setting switch and the like for setting the temperature are provided.

Next, the operation of the above configuration will be described. When the luggage compartment air conditioning operation switch on the operation panel 50 is turned on, the first compressor 21 operates to operate the luggage compartment air conditioning refrigeration cycle device 20 . The first bypass valve 25 and the first pressure equalizing valve 26 are closed during normal operation of the cargo room air conditioning refrigeration cycle device 20 .

When the first compressor 21 operates, the gaseous refrigerant discharged from the first compressor 21 flows into the first condenser 22 and is condensed and liquefied, and then decompressed by the first expansion valve 23 to the first evaporator 123. , the first evaporator 123 can cool the blown air to the luggage compartment 111 .

The refrigerant discharge amount (in other words, refrigerant discharge capacity) of the first compressor 21 is determined by the temperature in the luggage compartment 111 detected by the luggage compartment temperature sensor 41 and the first evaporator detected by the first evaporator temperature sensor 45. It is controlled based on the temperature of 123 and the like.

When it is determined that frost has formed on the first evaporator 123, a defrosting operation is performed. For example, when the time during which the temperature of the first evaporator 123 detected by the first evaporator temperature sensor 45 is equal to or lower than the frost formation determination temperature is equal to or longer than the frost formation determination time, the first evaporator 123 is frosted. determined to have occurred.

The first bypass valve 25 is opened in the defrosting operation. As a result, the high-temperature gas refrigerant discharged from the first compressor 21 is introduced into the first evaporator 123 through the first bypass passage 27, so that the first evaporator 123 is defrosted.

When the operating room air conditioning operation switch on the operation panel 50 is turned on, the second compressor 31 operates to operate the operating room air conditioning refrigeration cycle device 30 . During normal operation of the cab air conditioning refrigeration cycle device 30, the second bypass valve 35 and the second pressure equalizing valve 36 are closed. After the gas refrigerant discharged from the second compressor 31 flows into the second condenser 32 and is condensed and liquefied, it is decompressed by the second expansion valve 33 and supplied to the second evaporator 133, so that the second evaporation The blast air to the operator's cab 10 can be cooled by the device 133 .

The refrigerant discharge amount (in other words, refrigerant discharge capacity) of the second compressor 31 is determined by the vehicle interior temperature detected by the vehicle interior temperature sensor 42, the outside air temperature detected by the outside air temperature sensor 43, and the solar radiation sensor 44. Control is performed based on the amount of solar radiation in the passenger compartment, the temperature of the second evaporator 133 detected by the second evaporator temperature sensor 46, and the like.

When it is determined that frost has formed on the second evaporator 133, a defrosting operation is performed. For example, when the time during which the temperature of the second evaporator 133 detected by the second evaporator temperature sensor 46 is equal to or lower than the frost formation determination temperature is equal to or longer than the frost formation determination time, the second evaporator 133 is frosted. determined to have occurred.

The second bypass valve 35 is opened in the defrosting operation. As a result, the high-temperature gas refrigerant discharged from the second compressor 31 is introduced into the second evaporator 133 through the second bypass passage 37, so that the second evaporator 133 is defrosted.

Next, the pressure equalization control and the engine load control shown in the time chart of FIG. 4 will be described. When it is determined that the driver is stepping on the brake pedal and the brake negative pressure is insufficient (when determined as NG in the time chart of FIG. 4), the control device 40 performs pressure equalization control and engine load control. .

In this example, based on the detection signal of the brake switch 48, it is determined whether or not the driver is stepping on the brake pedal. In this example, when it is determined that the negative pressure of the intake air of the gasoline engine 2 is smaller than a predetermined value (that is, the negative pressure is closer to 0 than the predetermined value) based on the detection signal of the intake pressure sensor 47, the brake is applied. It is determined that the negative pressure is insufficient.

Engine load control is control for stopping the first compressor 21 for a predetermined stop time T1. The predetermined stop time T1 is set in advance as the time required for the negative pressure detected by the intake pressure sensor 47 to return to a normal value. The predetermined stop time T1 is, for example, about 2 to 3 seconds.

Since the engine load control reduces the load on the gasoline engine 2, the negative pressure of the intake pressure increases and returns to the normal negative pressure.

Pressure equalization control is control to open the first pressure equalization valve 26 and the first bypass valve 25 for a predetermined valve opening time T2. The predetermined valve opening time T2 is longer than the predetermined stop time T1. The predetermined valve opening time T2 is, for example, about 5 seconds. When the stop time of the first compressor 21 reaches the predetermined stop time T1, the first compressor 21 is operated.

By performing pressure equalization control while the first compressor 21 is stopped, the high pressure and the low pressure of the cargo room air conditioning/refrigerating cycle device 20 are equalized. Since the first compressor 21 is re-driven in a state in which the high and low pressures of the luggage compartment air-conditioning/refrigerating cycle device 20 are equalized, the magnetic clutch makes a large operating noise when the first compressor 21 is operated. It is possible to suppress the magnetic clutch from slipping and wearing.

When the opening time of the first pressure equalizing valve 26 and the first bypass valve 25 reaches the predetermined valve opening time T2, the first pressure equalizing valve 26 and the first bypass valve 25 are closed. Since the predetermined valve opening time T2 is longer than the predetermined stop time T1, it is possible to prevent the first pressure equalizing valve 26 and the first bypass valve 25 from closing before the first compressor 21 is driven again. . Therefore, before the first compressor 21 is driven again, the high pressure and the low pressure of the cargo room air conditioning/refrigerating cycle device 20 can be reliably equalized.

In this embodiment, when the brake pedal is stepped on and the negative pressure of the intake air of the gasoline engine 2 is smaller than a predetermined value, the control device 40 cuts off the driving force from the gasoline engine 2 and the first compressor The engine load control is performed to control the magnet clutch of the first compressor 21 so that the compressor 21 stops, and the first pressure equalizing valve 26 is opened so that the suction side and the discharge side of the first compressor 21 are communicated. Perform pressure equalization control.

According to this, the first compressor 21 is stopped when the brake pedal is depressed and the negative pressure of the intake air of the gasoline engine 2 is smaller than a predetermined value. Stopping the compressor 21 can be avoided.

Further, when the brake pedal is stepped on and the negative pressure of the intake air of the gasoline engine 2 is smaller than a predetermined value, the first pressure equalizing valve 26 is opened. High pressure and low pressure in the refrigeration cycle can be equalized. Therefore, since the first compressor 21 can be re-driven while the pressure inside the first compressor 21 is as low as possible, a large operating noise is generated when the gasoline engine 2 and the first compressor 21 are connected by the magnetic clutch. , it is possible to suppress the magnetic clutch from slipping and wearing out.

As described above, the stop frequency of the first compressor 21 can be reduced, and the re-driving of the first compressor 21 can be facilitated.

In this embodiment, the control device 40 controls the magnetic clutch so that the driving force is transmitted to the first compressor 21 when the stop time of the first compressor 21 reaches a predetermined stop time T1 or longer in engine load control. to end the engine load control. This makes it possible to re-drive the first compressor 21 with simple control.

In this embodiment, the control device 40 closes the first pressure equalizing valve 26 when the valve opening time of the first pressure equalizing valve 26 becomes equal to or longer than the predetermined valve opening time T2 in the pressure equalizing control, and ends the pressure equalizing control. As a result, the first pressure equalizing valve 26 can be closed by simple control, and the luggage compartment air-conditioning/refrigerating cycle device 20 can be returned to normal operation.

In this embodiment, the predetermined valve opening time T2 of the first pressure equalizing valve 26 is longer than the predetermined stop time T1 of the first compressor 21 . This can prevent the first pressure equalizing valve 26 and the first bypass valve 25 from being closed before the first compressor 21 is restarted, so that the load can be discharged before the first compressor 21 is restarted. The high pressure and low pressure of the room air conditioning refrigeration cycle device 20 can be reliably equalized. Before re-driving the first compressor 21, the high pressure and low pressure of the cargo room air conditioning/refrigerating cycle device 20 can be equalized.

In this embodiment, the control device 40 opens the first pressure equalizing valve 26 in the pressure equalizing control, and the refrigerant discharged from the first compressor 21 bypasses the first condenser 22 and the first expansion valve 23. Then, the first bypass valve 25 is opened so as to lead to the first evaporator 123 .

As a result, in the pressure equalization control, the high pressure and low pressure of the cargo room air conditioning refrigeration cycle device 20 can be equalized through the first bypass flow path 27 as well, so that the high pressure and low pressure of the refrigeration cycle are reliably equalized. can.

In the present embodiment, the control device 40 closes the first pressure equalizing valve 26 and closes the first bypass valve 25 when the opening time of the first pressure equalizing valve 26 reaches the predetermined valve opening time T2 or longer in the pressure equalizing control. The valve is closed to end pressure equalization control.

As a result, the first pressure equalizing valve 26 and the first bypass valve 25 can be closed by simple control, and the luggage compartment air-conditioning/refrigerating cycle apparatus 20 can be returned to normal operation.

(Other embodiments)
It should be noted that the present invention is not limited to the above-described embodiments, and can be variously modified as follows.

(1) In the above-described embodiment, the engine load control shown in the time chart of FIG. 4 ends at the predetermined stop time T1. However, the engine load control ends when the intake negative pressure of the gasoline engine 2 reaches or exceeds a predetermined value. You may do so.

In the above-described embodiment, the pressure equalization control shown in the time chart of FIG. 4 ends at the predetermined valve opening time T2. You may make it finish pressure control.

(2) In the above-described embodiment, the engine load control and the pressure equalization control shown in the time chart of FIG. That is, the first compressor 21 is stopped in engine load control, and the first pressure equalizing valve 26 and the first bypass valve 25 are opened in pressure equalizing control.

On the other hand, engine load control and pressure equalization control shown in the time chart of FIG. That is, the second compressor 31 may be stopped in the engine load control, and the second pressure equalizing valve 36 and the second bypass valve 35 may be opened in the pressure equalizing control.

(3) The engine load control in the above-described embodiment is the control to stop the first compressor 21 or the second compressor 31, but the engine load control is the alternator 4, the sub-alternator (not shown), the hydraulic pump (not shown), (not shown), a water pump (not shown), or other in-vehicle equipment may be stopped.

Alternator 4 is a generator driven by gasoline engine 2 . The electric power generated by the alternator 4 is used for charging the vehicle-mounted battery. A sub-alternator is a generator driven by the gasoline engine 2 . The electric power generated by the sub-alternator is used to charge the in-vehicle sub-battery. The hydraulic pump is a pump that is driven by the gasoline engine 2 to generate hydraulic pressure. The water pump is a pump that is driven by the gasoline engine 2 to circulate cooling water.

That is, the engine load control may be any control that stops the in-vehicle device that loads the gasoline engine 2 . As a result, when the brake pedal is depressed and the negative pressure of the intake air of the gasoline engine 2 is smaller than a predetermined value, the load on the gasoline engine 2 is reduced by stopping the in-vehicle equipment. The pressure increases and returns to normal negative pressure.

When the brake pedal is depressed and the intake negative pressure of the gasoline engine 2 is less than a predetermined value, the on-vehicle equipment is stopped. It is possible to reduce the frequency of stopping the on-vehicle device compared to when the on-vehicle device is stopped regardless of whether the pedal is stepped on.

In-vehicle equipment to be stopped in the engine load control is desirably a device that does not immediately affect running of the vehicle even if it is stopped. As a result, it is possible to reduce the frequency of stoppage of the in-vehicle device without impairing the safety of running the vehicle.

(4) In the above-described embodiment, an HFC-based refrigerant (specifically, R134a) with low ozone depletion ability is adopted as the refrigerant of the refrigeration cycle device, but it is not limited to this, and other refrigerants may be used. various refrigerants (for example, so-called new refrigerants with low global warming potential) may be employed.

(5) In the above-described embodiment, the cargo room air conditioning refrigerating cycle device 20 and the driver's compartment air conditioning refrigerating cycle device 30 are provided as refrigerating cycle devices. may be provided.

Further, in the above-described embodiment, an example in which the refrigeration cycle device is applied to the transportation vehicle 1 has been described, but the refrigeration cycle device can be applied to various vehicles without being limited to this.

The characteristics of the vehicular refrigeration cycle apparatus and the in-vehicle equipment control apparatus disclosed in the present specification are as follows.
(Item 1)
a compressor (21) driven by the gasoline engine (2) for sucking, compressing and discharging refrigerant;
a radiator (22) for dissipating heat from the refrigerant discharged from the compressor (21);
a decompression unit (23) for decompressing the refrigerant radiated by the radiator (22);
an evaporator (123) for evaporating the refrigerant decompressed by the decompression unit (23);
a pressure equalizing section (28) for equalizing the pressure by communicating the suction side and the discharge side of the compressor (21);
a pressure equalizing valve (26) for opening and closing the pressure equalizing section (28);
a control unit (40) for controlling a magnetic clutch for interrupting driving force transmitted from the gasoline engine (2) to the compressor (21) and the pressure equalizing valve (26);
The control unit (40) controls the operation when a brake pedal whose operating force is reduced by a brake booster that utilizes the negative pressure of the intake air of the gasoline engine (2) is stepped on and the negative pressure is smaller than a predetermined value. , the engine load control is performed to control the magnetic clutch so that the driving force is interrupted and the compressor (21) is stopped, and the suction side and the discharge side of the compressor (21) are communicated. A vehicle refrigeration cycle device that performs pressure equalization control for opening the pressure equalizing valve (26).
(Item 2)
The control unit (40) controls the engine load so that the driving force is transmitted to the compressor (21) when the stop time of the compressor (21) reaches a predetermined stop time (T1) or more. The vehicle refrigeration cycle apparatus according to item 1, wherein the engine load control is terminated by controlling a magnet clutch.
(Item 3)
The control unit (40) closes the pressure equalizing valve (26) when the valve opening time of the pressure equalizing valve (26) reaches a predetermined valve opening time (T2) or longer in the pressure equalizing control, thereby performing the pressure equalizing control. 3. The vehicular refrigeration cycle device according to item 1 or 2, which ends the above.
(Item 4)
The control unit (40)
In the engine load control, when the stop time of the compressor (21) reaches a predetermined stop time (T1) or more, the magnetic clutch is controlled so that the driving force is transmitted to the compressor (21), and the engine is end load control,
In the pressure equalizing control, when the valve opening time of the equalizing valve (26) reaches a predetermined valve opening time (T2) longer than the predetermined stop time (T1), the equalizing valve (26) is closed and the equalizing control is performed. 3. The vehicular refrigeration cycle device according to item 1 or 2, which terminates pressure control.
(Item 5)
a bypass section (27) that bypasses the radiator (22) and the pressure reducing section (23) and guides the refrigerant discharged from the compressor (21) to the evaporator;
A bypass valve (25) for opening and closing the bypass section (27),
In the pressure equalization control, the control section (40) opens the pressure equalization valve (26) and causes the refrigerant discharged from the compressor (21) to flow through the radiator (22) and the decompression section ( 23) and the bypass valve (25) is opened to bypass the evaporator (123).
(Item 6)
The control unit (40) closes the pressure equalizing valve (26) and closes the bypass valve (26) when the valve opening time of the pressure equalizing valve (26) reaches a predetermined valve opening time (T2) or longer in the pressure equalizing control. 25) is closed to terminate the pressure equalization control.
(Item 7)
a compressor (21) driven by the gasoline engine (2) for sucking, compressing and discharging refrigerant;
a radiator (22) for dissipating heat from the refrigerant discharged from the compressor (21);
a decompression unit (23) for decompressing the refrigerant radiated by the radiator (22);
an evaporator (123) for evaporating the refrigerant decompressed by the decompression unit (23);
A control unit (40) for controlling a magnetic clutch that interrupts driving force transmitted from the gasoline engine (2) to the compressor (21),
The control unit (40) controls the operation when a brake pedal whose operating force is reduced by a brake booster that utilizes the negative pressure of the intake air of the gasoline engine (2) is stepped on and the negative pressure is smaller than a predetermined value. A refrigeration cycle device for a vehicle that performs engine load control for controlling the magnetic clutch so that the driving force is interrupted and the compressor (21) stops.
(Item 8)
When a brake pedal whose operation force is reduced by a brake booster that utilizes the negative pressure of the intake air of the gasoline engine (2) is stepped on and the negative pressure is smaller than a predetermined value, the gasoline engine (2) is loaded. An in-vehicle equipment control device comprising a control unit (40) for stopping in-vehicle equipment (4, 21) that applies
(Item 9)
The in-vehicle device is a compressor (21) that is driven by the gasoline engine (2) and sucks, compresses, and discharges refrigerant from a refrigeration cycle device,
When the brake pedal is depressed and the negative pressure is smaller than a predetermined value, the control unit (40) interrupts driving force transmitted from the gasoline engine (2) to the compressor (21). 9. The in-vehicle device control device according to item 8, wherein the compressor (21) is stopped by controlling the magnet clutch to cut off the driving force.

21 first compressor (compressor)
22 first condenser (radiator)
23 1st expansion valve (decompression part)
25 first bypass valve (bypass valve)
26 First equalizing valve (equalizing valve)
27 first bypass flow path (bypass section)
28 first pressure equalizing flow path (pressure equalizing section)
40 control device (control unit)
123 first evaporator (evaporator)

Claims (9)

a compressor (21) driven by the gasoline engine (2) for sucking, compressing and discharging refrigerant;
a radiator (22) for dissipating heat from the refrigerant discharged from the compressor (21);
a decompression unit (23) for decompressing the refrigerant radiated by the radiator (22);
an evaporator (123) for evaporating the refrigerant decompressed by the decompression unit (23);
a pressure equalizing section (28) for equalizing the pressure by communicating the suction side and the discharge side of the compressor (21);
a pressure equalizing valve (26) for opening and closing the pressure equalizing section (28);
a control unit (40) for controlling a magnetic clutch for interrupting driving force transmitted from the gasoline engine (2) to the compressor (21) and the pressure equalizing valve (26);
The control unit (40) controls the operation when a brake pedal whose operating force is reduced by a brake booster that utilizes the negative pressure of the intake air of the gasoline engine (2) is stepped on and the negative pressure is smaller than a predetermined value. , the engine load control is performed to control the magnetic clutch so that the driving force is interrupted and the compressor (21) is stopped, and the suction side and the discharge side of the compressor (21) are communicated. A vehicle refrigeration cycle device that performs pressure equalization control for opening the pressure equalizing valve (26). The control unit (40) controls the engine load so that the driving force is transmitted to the compressor (21) when the stop time of the compressor (21) reaches a predetermined stop time (T1) or more. 2. The vehicle refrigeration cycle apparatus according to claim 1, wherein said engine load control is terminated by controlling a magnet clutch. The control unit (40) closes the pressure equalizing valve (26) when the valve opening time of the pressure equalizing valve (26) reaches a predetermined valve opening time (T2) or longer in the pressure equalizing control, thereby performing the pressure equalizing control. 2. The refrigeration cycle apparatus for a vehicle according to claim 1, wherein the . The control unit (40)
In the engine load control, when the stop time of the compressor (21) reaches a predetermined stop time (T1) or more, the magnetic clutch is controlled so that the driving force is transmitted to the compressor (21), and the engine is end load control,
In the pressure equalizing control, when the valve opening time of the equalizing valve (26) reaches a predetermined valve opening time (T2) longer than the predetermined stop time (T1), the equalizing valve (26) is closed and the equalizing control is performed. 2. The vehicle refrigeration cycle apparatus according to claim 1, wherein the pressure control is terminated. a bypass section (27) that bypasses the radiator (22) and the pressure reducing section (23) and guides the refrigerant discharged from the compressor (21) to the evaporator;
A bypass valve (25) for opening and closing the bypass section (27),
In the pressure equalization control, the control section (40) opens the pressure equalization valve (26) and causes the refrigerant discharged from the compressor (21) to flow through the radiator (22) and the decompression section ( 5. The vehicle refrigeration cycle apparatus according to any one of claims 1 to 4, wherein the bypass valve (25) is opened so as to bypass 23) and lead to the evaporator (123). The control unit (40) closes the pressure equalizing valve (26) and closes the bypass valve (26) when the valve opening time of the pressure equalizing valve (26) reaches a predetermined valve opening time (T2) or longer in the pressure equalizing control. 25) is closed to end the pressure equalization control. a compressor (21) driven by the gasoline engine (2) for sucking, compressing and discharging refrigerant;
a radiator (22) for dissipating heat from the refrigerant discharged from the compressor (21);
a decompression unit (23) for decompressing the refrigerant radiated by the radiator (22);
an evaporator (123) for evaporating the refrigerant decompressed by the decompression unit (23);
A control unit (40) for controlling a magnetic clutch that interrupts driving force transmitted from the gasoline engine (2) to the compressor (21),
The control unit (40) controls the operation when a brake pedal whose operating force is reduced by a brake booster that utilizes the negative pressure of the intake air of the gasoline engine (2) is stepped on and the negative pressure is smaller than a predetermined value. A refrigeration cycle device for a vehicle that performs engine load control for controlling the magnetic clutch so that the driving force is interrupted and the compressor (21) stops. When a brake pedal whose operation force is reduced by a brake booster that utilizes the negative pressure of the intake air of the gasoline engine (2) is stepped on and the negative pressure is smaller than a predetermined value, the gasoline engine (2) is loaded. An in-vehicle equipment control device comprising a control unit (40) for stopping in-vehicle equipment (4, 21) that applies The in-vehicle device is a compressor (21) that is driven by the gasoline engine (2) and sucks, compresses, and discharges refrigerant from a refrigeration cycle device,
When the brake pedal is depressed and the negative pressure is smaller than a predetermined value, the control unit (40) interrupts driving force transmitted from the gasoline engine (2) to the compressor (21). 9. The in-vehicle equipment control device according to claim 8, wherein the compressor (21) is stopped by controlling the magnetic clutch to cut off the driving force.

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