JP2003080935A - Freezing cycle device for vehicle, and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a freezing cycle device for a vehicle, and a control method thereof, capable of securing acceleration performance of the vehicle, and securing cooling ability matching the degree of acceleration. SOLUTION: This freezing cycle device 1 provided with a variable displacement compressor 2 using a vehicle engine 11 as a drive source, comprises an acceleration determining means to determine a degree of acceleration of the vehicle, and a control determining means to determine a control pattern of a load of the compressor 2 to the engine 11 in accordance with the result of determination. When the vehicle is accelerated, the displacement of the compressor 2 is controlled so that the compressor load may be subjected to the determined control pattern. In this device, the load of the compressor is controlled in accordance with the prescribed control patterns under consideration for securing acceleration performance determined corresponding to the degree of acceleration of the vehicle and securing the cooling ability, and accordingly the load of the compressor is properly controlled in accordance with the degree of acceleration of the vehicle. Acceleration performance of the vehicle and cooling ability matching that can thus be secured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle refrigeration cycle apparatus and a control method thereof.

[0002]

2. Description of the Related Art In a vehicle refrigeration cycle apparatus equipped with a compressor driven by a vehicle engine, when the vehicle is accelerated, the cooling capacity of the vehicle refrigeration cycle apparatus is ensured without impairing the acceleration of the vehicle. It is desired to do.

In this regard, in Japanese Patent Laid-Open No. 62-8820, it is required to accelerate the vehicle by using a control map defined by the throttle opening and the vehicle speed (that is, the acceleration request range in the control map). If it is determined to be in), the control method of shutting off the compressor for a predetermined time is disclosed.

However, in this method, when the vehicle is requested to accelerate (being within the acceleration request range in the control map), the compressor is simply stopped, so that the acceleration of the vehicle is improved. However, on the other hand, it is difficult to secure the cooling capacity of the vehicle refrigeration cycle device.

To solve this problem, Japanese Patent Laid-Open No. 2000-3
Japanese Patent No. 35232 discloses a refrigeration cycle device for a vehicle using a variable capacity compressor. Here, the maximum acceleration at which the occupant feels the acceleration of the vehicle during vehicle acceleration occurs in a short time immediately after the start of acceleration, and if the refrigerant circulates in the refrigeration cycle even at a relatively small flow rate, air conditioning Focusing on the ability to suppress the rise in the temperature of air blown out of the equipment, stop the compressor for a short time at the start of acceleration, and then gradually restore the capacity in partial capacity operation to ensure the acceleration and cooling capacity of the vehicle. I am trying to achieve both.

However, in this refrigeration cycle apparatus, control is not performed according to the degree of acceleration of the vehicle, and the compressor is similarly stopped regardless of whether it is sudden acceleration or gentle acceleration (slow acceleration). And the capacity control thereafter is performed. Therefore, at the time of gentle acceleration with a small acceleration, the cooling effect is large despite the small acceleration effect,
There is a problem that the cooling capacity commensurate with the acceleration is not secured.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to ensure the accelerating property of a vehicle at the time of accelerating the vehicle and to cool the vehicle in proportion to the degree of acceleration of the vehicle. An object of the present invention is to provide a vehicle refrigeration cycle device capable of ensuring capacity and a control method thereof.

[0008]

As a means for solving the above problems, the present invention provides a refrigeration cycle apparatus for a vehicle as set forth in claims 1 to 4 of the claims and claims 5 to 8. Provided is a method for controlling the described vehicle refrigeration cycle apparatus.

According to a first aspect of the present invention, there is provided a vehicle refrigeration cycle apparatus including a variable displacement compressor having a vehicle engine as a drive source, and acceleration determining means for determining the degree of acceleration of the vehicle, and the determination thereof. And a control determination means for determining a control pattern of the load of the compressor on the engine according to the result, and at the time of acceleration of the vehicle, the capacity of the compressor is set so that the load of the compressor becomes the above-mentioned determined control pattern. A refrigeration cycle device for a vehicle, which is controlled in accordance with the present invention.

In this vehicle refrigeration cycle apparatus,
The load of the compressor on the engine is controlled according to a predetermined control pattern from the viewpoint of ensuring both the acceleration of the vehicle, which is determined according to the degree of acceleration of the vehicle, and the cooling capacity of the refrigeration cycle device. Therefore, the load of the compressor on the engine is appropriately controlled according to the degree of acceleration of the vehicle, and when the vehicle is accelerated, the acceleration of the vehicle is ensured and the cooling capacity that is commensurate with the degree of acceleration of the vehicle is ensured. Is possible.

According to a second aspect of the present invention, in the vehicular refrigeration cycle apparatus according to the first aspect, the control determining means requires the load of the compressor on the engine according to the determination result of the acceleration determining means. A reduction amount is determined, the capacity of the compressor is controlled so that the load of the compressor is reduced by the required reduction amount at the start of vehicle acceleration, and then the capacity of the compressor is gradually recovered. A refrigeration cycle device for a vehicle is provided.

That is, in this refrigeration cycle apparatus, the necessary reduction amount of the load of the compressor on the engine is determined as an element of the control pattern determined according to the degree of acceleration, and this required reduction is performed at the start of acceleration of the vehicle. The capacity of the compressor is controlled so that the load of the compressor is reduced by an amount, and then the capacity of the compressor is controlled to gradually recover. As a result, a sufficient engine output for acceleration is secured especially at the start of acceleration of the vehicle, and the cooling capacity is secured by gradually recovering the capacity of the compressor. Therefore, even with such a vehicle refrigeration cycle apparatus, it is possible to ensure the acceleration performance of the vehicle at the time of acceleration of the vehicle and the cooling capacity suitable for the degree of acceleration of the vehicle.

The invention described in claim 3 is the invention according to claim 1 or 2.
In the refrigeration cycle apparatus for a vehicle described in (1), the acceleration determination means determines a degree of acceleration of the vehicle based on a vehicle speed and an accelerator opening degree, or a vehicle speed and a throttle opening degree. With such a configuration, it is possible to easily and surely determine the degree of acceleration.

The invention according to claim 4 is the invention according to claim 2 or 3.
In the vehicle refrigeration cycle apparatus described in the paragraph (1), the control determination means determines a required reduction torque as a required reduction amount of the load of the compressor, and the compressor is a compressor whose capacity is controlled by a control current signal from the outside. , Control current signal,
The compressor torque is calculated based on the compressor discharge pressure and the engine speed, the target reduction torque is determined by subtracting the required reduction torque from the compression torque, and the target compression torque and the discharge pressure of the compressor are determined. And a target refrigeration cycle signal for which a target control current signal is determined based on the engine speed, and the capacity of the compressor is controlled by the target control current signal at the start of acceleration of the vehicle. This allows
The control of the compressor load based on the compressor torque is realized, and the control of the compressor torque is executed by the control of the compressor capacity by the control current signal, so that more reliable control of the compressor load is possible. Become.

According to a fifth aspect of the present invention, there is provided a method of controlling a refrigeration cycle apparatus for a vehicle, comprising a variable displacement compressor driven by a vehicle engine, wherein a step of determining a degree of acceleration of the vehicle. , A step of determining a control pattern of the load of the compressor on the engine according to the determination result, and a step of controlling the capacity of the compressor so that the load of the compressor becomes the determined control pattern. Provided is a method for controlling a vehicle refrigeration cycle device having the same.

As a result, the load of the compressor on the engine is set to a predetermined value from the viewpoint of ensuring both the acceleration of the vehicle, which is determined according to the degree of acceleration of the vehicle, and the cooling capacity of the refrigeration cycle apparatus. Since it is controlled according to the control pattern, the load of the compressor on the engine is appropriately controlled according to the degree of acceleration of the vehicle, and when the vehicle is accelerating, the acceleration of the vehicle is ensured and the degree of acceleration of the vehicle is matched. It is possible to secure the cooling capacity.

According to a sixth aspect of the present invention, in the control method according to the fifth aspect, the step of determining the control pattern comprises:
The step of controlling the capacity of the compressor includes the step of determining the necessary reduction amount of the load of the compressor on the engine according to the result of the step of determining the degree of acceleration. A control method of a refrigeration cycle apparatus for a vehicle, including the step of controlling the capacity of the compressor so that the load of the compressor is reduced by a required reduction amount and then gradually recovering the capacity of the compressor. .

That is, in this method, the required reduction amount of the load of the compressor on the engine is determined as an element of the control pattern determined according to the degree of acceleration, and at the start of vehicle acceleration, the required reduction amount is reduced. The capacity of the compressor is controlled so that the load on the compressor is reduced, and then the capacity of the compressor is controlled to gradually recover.
As a result, a sufficient engine output for acceleration is secured especially at the start of acceleration of the vehicle, and the cooling capacity is secured by gradually recovering the capacity of the compressor. Therefore, it becomes possible to secure the acceleration of the vehicle during the acceleration of the vehicle and also to secure the cooling capacity corresponding to the degree of acceleration of the vehicle.

The invention according to claim 7 is the invention according to claim 5 or 6.
In the control method according to, the step of determining the degree of acceleration includes the step of determining the degree of acceleration of the vehicle based on the vehicle speed and the accelerator opening, or the vehicle speed and the throttle opening. Provide a control method.
This makes it possible to easily and surely determine the degree of acceleration.

The invention according to claim 8 is the invention according to claim 6 or 7.
In the control method described in (1), the step of determining the control pattern includes the step of determining a required reduction torque as a required reduction amount of the load of the compressor, and the compressor whose capacity is controlled by an external control current signal. That is, the step of controlling the capacity of the compressor is to calculate the compressor torque based on the control current signal, the discharge pressure of the compressor, and the number of revolutions of the engine, and the required reduction torque from the compressor torque. The target compressor torque is subtracted, the target compressor torque, the compressor discharge pressure, and the target control current signal based on the engine speed are determined. Controlling the capacity of the compressor according to a control current signal. As a result, the control of the compressor load based on the compressor torque is realized, and the control of the compressor torque is executed by the control of the compressor capacity by the control current signal. Is possible.

[0021]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described in detail below with reference to the drawings. In the drawings, the same or similar components are designated by common reference numerals.

FIG. 1 is an overall configuration diagram of a system including a vehicle refrigeration cycle apparatus according to an embodiment of the present invention. The refrigeration cycle device 1 for vehicle air conditioning sucks and compresses refrigerant,
A compressor 2 for discharging is provided. The high-temperature, high-pressure superheated gas refrigerant discharged from the compressor 2 flows into the condenser 3, where it exchanges heat with the outside air blown from a cooling fan (not shown), and the refrigerant is cooled and condensed.

The refrigerant condensed in the condenser 3 then flows into the liquid receiver (gas-liquid separator) 4, the gas-liquid of the refrigerant is separated inside the liquid receiver 4, and the surplus in the refrigeration cycle apparatus 1 is separated. Refrigerant (liquid refrigerant) is stored in the receiver 4. The liquid refrigerant from the liquid receiver 4 is decompressed to a low pressure by the expansion valve (decompression means) 5 and becomes a gas-liquid two-phase state. The low pressure refrigerant from the expansion valve 5 flows into the evaporator 6. The evaporator 6 is installed in an air conditioning case 7 that constitutes an air passage of a vehicle air conditioner, and the low-pressure refrigerant flowing into the evaporator 6 absorbs heat from the air in the air conditioning case 7 and evaporates.

The expansion valve 5 is a temperature type expansion valve having a temperature sensing part 5a for detecting the temperature of the outlet refrigerant of the evaporator 6, and is opened to maintain the superheat degree of the outlet refrigerant of the evaporator 6 at a predetermined value. Temperature (refrigerant flow rate). The above-mentioned cycle components (2 to 6) are connected by a refrigerant pipe 8 to form a closed circuit.

The compressor 2 is driven by a vehicle running engine (E / G) 11 via a power transmission mechanism 9, a belt 10 and the like. The compressor 2 is a variable capacity compressor as described later. In the present embodiment, the power transmission mechanism 9 is
A clutch mechanism (for example, an electromagnetic clutch) in which power transmission / disengagement can be selected by electrical control from the outside is a clutchless mechanism of a power transmission type without such a clutch mechanism. May be.

The air-conditioning case 7 is provided with a blower 12, and the air inside the vehicle (inside air) or the air outside the vehicle (outside air) sucked in from a well-known inside / outside air switching box (not shown) is blown by the blower 12. The air is blown from the inside of the air conditioning case 7 toward the passenger compartment. After passing through the evaporator 6, the blown air passes through a heater unit (not shown) and is blown out into the vehicle compartment from the air outlet.

An evaporator blow-out temperature sensor 13 including a thermistor for detecting the temperature of blown air immediately after passing through the evaporator 6 is provided in a portion of the air conditioning case 7 immediately downstream of the evaporator 6. ing.

The above-mentioned heater unit is well known, and is a hot water type heater core (heating means) for reheating the cold air passing through the evaporator 6, and an air forming a temperature adjusting means for adjusting the heating degree of the hot water type heater core. A mix door, a hot water flow control valve, or the like is provided. Further, at the air downstream end of the air conditioning case 7, a face outlet that blows air to the upper half of the passenger in the passenger compartment, and a foot that blows air to the feet of the passenger in the passenger compartment. A defroster outlet that blows air is formed on the inner surface of the windshield and the windshield, and a blowout mode door that switches and opens these outlets is provided.

By the way, the above-described compressor 2 has an electromagnetic capacity control valve (discharge capacity control mechanism) 15 controlled by an electric signal from an air conditioning control unit (A / C ECU) 14, and this control valve 15 This is an external variable displacement compressor that changes the control pressure to change the discharge capacity. The air conditioning controller 14 includes a sensor group 16 for automatic air conditioning control.
Detection signal and the operation signal of the operation switch group of the air conditioning operation panel 17 are input.

The sensor group 16 is specifically an inside air sensor, an outside air sensor, a solar radiation sensor, an engine water temperature sensor, etc. The operation switch group of the air conditioning operation panel 17 is specifically a temperature setting switch, an air flow rate. A changeover switch, a blowout mode changeover switch, an inside / outside air changeover switch, an air conditioner switch for issuing an operation command for the compressor 2, and the like.

Further, in the refrigeration cycle apparatus 1, a high pressure sensor 1 for detecting a high pressure (compressor discharge pressure) in a high pressure circuit section from the discharge side of the compressor 2 to the inlet of the expansion valve 5.
8 is provided so that the detection signal of the high pressure sensor 18 is also input to the air conditioning controller 14. In the illustrated example, the high pressure sensor 18 is provided in the outlet side refrigerant pipe of the condenser 3.

Further, the air-conditioning control device 14 is connected to an engine control device (E / GECU) 19 on the vehicle side so that signals can be input and output between the control devices 14 and 19. ing. As is well known, the engine control device 19 is based on a signal from a sensor group 19a that detects a driving condition of the vehicle engine 11 and the like.
The amount of fuel to be injected into the engine, the ignition timing, etc. are comprehensively controlled.

In the present embodiment, information such as engine speed, vehicle speed and throttle opening or accelerator opening is transmitted from the engine control device 19 to the air conditioning control device 14 to determine the degree of acceleration as will be described later. It is used to calculate the compressor load (torque).

FIG. 2 is a sectional view showing the external variable displacement compressor 2 used in this embodiment. In the compressor 2, the target flow rate Gr of the compressor discharge flow rate is controlled by the control current (that is, the control current signal) In of the electromagnetic capacity control valve 15.
o is set, and the discharge capacity is increased or decreased so that the compressor discharge flow rate is maintained at the target flow rate Gro (discharge quantity control type). More specifically, the target flow rate Gro increases in proportion to the increase of the control current In.

As shown in FIG. 2, the compressor 2 is a swash plate type variable displacement compressor, and its variable displacement mechanism itself is well known. The power of the vehicle engine 11 is transmitted to the rotating shaft 20 via the power transmission mechanism 9 of FIG. The left end portion of the rotary shaft 20 in FIG. 2 is a connecting portion with the power transmission mechanism 9. The swash plate 21 is integrally rotatably connected to the rotary shaft 20, and the inclination angle of the swash plate 21 can be adjusted by a spherical hinge mechanism 22. In addition, swash plate 2
The solid line position 1 indicates a state where the tilt angle with respect to the rotary shaft 20 is small (small capacity state), and the two-dot chain line position 21a indicates a state where the tilt angle with respect to the rotary shaft 20 is large (large capacity state).

Plural (for example, five) pistons 24 are connected to the swash plate 21 via shoes 23. Therefore, by rotating the swash plate 21 integrally with the rotating shaft 20, the plurality of pistons 24 are sequentially reciprocated through the shoes 23 to expand or reduce the volume of the cylinder chamber (working chamber) Vc, and thereby the refrigerant. It is designed to be inhaled and compressed.

When the discharge capacity of the compressor 2 is changed, the swash plate 21 is housed in the crank chamber (swash plate chamber).
By changing the pressure Pc in 25, the inclination angle of the swash plate 21 is changed and the stroke (stroke) of the piston 24 is changed. That is, as the tilt angle of the swash plate 21 increases, the piston stroke increases and the discharge capacity increases, and when the tilt angle of the swash plate 21 decreases, the piston stroke decreases and the discharge capacity decreases.

Therefore, the crank chamber 25 also serves as a control pressure chamber for changing the discharge capacity of the compressor 2. The crank chamber (swash plate chamber) 25 communicates with the suction chamber 27 side of the compressor 20 via the throttle passage 26.

On the other hand, a first discharge chamber 29 and a second discharge chamber 30 are formed in the rear housing 28 of the compressor 20, and the first discharge chamber 29 has a throttle communication passage (throttle section) 31 having a predetermined throttle hole diameter. Through the second discharge chamber 30. First
The discharge chamber 29 has a working chamber (cylinder chamber) for each piston 24.
The refrigerant discharged from Vc is the discharge port 33 of the valve plate 32,
It flows in through the discharge valve 34, is collected, and the discharge pulsation is smoothed. The second discharge chamber 30 is connected to an external refrigerant discharge pipe via a discharge port 35.

Further, the rear housing 28 includes an evaporator 6
A suction port 36 for sucking the low-pressure gas refrigerant from the outlet and a suction chamber 27 through which the refrigerant flows from the suction port 36 are provided. The refrigerant is sucked into the working chamber Vc from the suction chamber 27 through the suction port 37 and the suction valve 38 of the valve plate 32.

Refrigerant is drawn from the first discharge chamber 29 by the throttle communication passage 31.
Since a pressure loss occurs when flowing through the second discharge chamber 30 toward the second discharge chamber 30, the pressure Pd _L in the second discharge chamber 30 is lower than the pressure Pd _H in the first discharge chamber 29 by a predetermined amount ΔP. Become. The differential pressure ΔP before and after the throttle communication passage 31 has a magnitude corresponding to the flow rate of refrigerant discharged from the compressor.

The electromagnetic capacity control valve 15 constitutes a discharge capacity control mechanism for controlling the pressure Pc in the crank chamber 25 which is a control pressure chamber, and is arranged on the rear housing 28 side of the compressor 2. Next, a specific configuration example of the capacity control valve 15 will be described. The control valve 15 includes a first control chamber 40 through which the pressure Pd _H in the first discharge chamber 29 is introduced via a communication passage 39, and a first control chamber 40. A second control chamber 42 is provided in which the pressure Pd _L in the second discharge chamber 30 is guided via the communication passage 41. The control chambers 40 and 42 are partitioned by a slidable cylindrical member 43. Thereby, the cylindrical member 43
To both control chambers 4 at one end of the push rod 44 through
The force due to the differential pressure ΔP between 0 and 42 acts as a force in the valve opening direction.

The discharge pressure chamber 45 into which the pressure Pd _H in the first discharge chamber 29 is introduced and the crank chamber 25 are connected to the communication passage 4
A control pressure chamber 47 communicating with the control valve 15 is provided in the control valve 15, and a throttle passage 48 is provided between the discharge pressure chamber 45 and the control pressure chamber 47.
And the opening cross-sectional area of the throttle passage 48 is adjusted by the valve body 49 of the push rod 44, so that the control pressure chamber 4
7, the pressure of the crank chamber 25 (control pressure)
Pc can be adjusted.

On the other hand, the electromagnetic mechanism 50 of the control valve 15 acts on the valve body 49 (push rod 44) with a force that opposes the valve opening force due to the differential pressure ΔP, that is, the valve closing force. The valve body 49 is integrally connected to a plunger (movable iron core) 51 of the electromagnetic mechanism portion 50, and the electromagnetic attraction force induced by the exciting coil 52 acts on the plunger 51. That is, the plunger 51 is arranged to face the fixed magnetic pole member (fixed iron core) 53 at a predetermined interval, and the plunger 51 is axially directed toward the fixed magnetic pole member 53 by the electromagnetic attraction force induced by the exciting coil 52 (see FIG. 2 upward). The axial displacement of the plunger 51 causes the valve element 49 to move in the valve closing direction.

Further, the plunger 51 and the fixed magnetic pole member 53
A coil spring 54 is disposed between and as an elastic means for generating an elastic force that opposes the electromagnetic force.

In this example, the control current (control current signal) In supplied to the exciting coil 52 is controlled (for example, the intermittent ratio of the control current In, that is, the duty ratio D).
By controlling t), a desired electromagnetic attraction force (that is, force in the valve closing direction of the valve body 49) can be applied to the plunger 51. The control current In of the exciting coil 52 is controlled by the air conditioning controller 14 described above.

Since the electromagnetic capacity control valve 15 is constructed as described above, when the control current In is controlled to increase the valve closing force of the valve body 49, the valve body 49 is displaced upward in FIG. Since the opening cross-sectional area of the throttle passage 48 is reduced, the pressure of the control pressure chamber 47, that is, the pressure Pc of the crank chamber 25 decreases, and the inclination angle of the swash plate 21 becomes as shown by the chain double-dashed line 21a in FIG. Increase, which increases the discharge volume.

On the contrary, when the control current In is controlled to reduce the valve closing force of the valve body 49, the valve body 49 causes the coil spring 5 to move.
2 is displaced downward in FIG. 2 to increase the opening cross-sectional area of the throttle passage 48, so that the pressure in the control pressure chamber 47, that is, the pressure Pc in the crank chamber 25 increases, and the inclination angle of the swash plate 21 increases. Decreases as indicated by the solid line position in FIG. 2 and the discharge volume decreases accordingly.

On the other hand, when the rotation speed of the engine 11 rises and the rotation speed of the compressor 2 rises, the compressor 2 is interlocked with this.
The flow rate of the discharged refrigerant discharged from the fuel cell increases, but when the flow rate of the discharged refrigerant increases, the pressure difference Δ between the first and second control chambers 40 and 42 increases.
Since P becomes larger, the valve opening force becomes larger, and the push rod 44 and the valve body 49 move downward in FIG. 2 to increase the opening cross-sectional area of the throttle passage 48, so the discharge capacity of the compressor 2 decreases. I will do it.

On the contrary, when the rotation speed of the engine 11 decreases and the rotation speed of the compressor 2 decreases, the compressor 2 is interlocked with this.
The flow rate of the discharged refrigerant discharged from the device decreases, but when the flow rate of the discharged refrigerant decreases, the differential pressure Δ between the first and second control chambers 40 and 42 is decreased.
Since P becomes smaller, the valve opening force becomes smaller, and the push rod 44 and the valve body 49 move upward in FIG. 2 to reduce the opening cross-sectional area of the throttle passage 48, so the discharge capacity of the compressor 2 increases. I will do it.

At this time, the push rod 44 and the valve body 4
9 moves to a position where the valve closing force and the valve opening force are balanced,
This means that the discharge capacity of the compressor 2 is reduced until the differential pressure ΔP between the first and second control chambers 40 and 42 reaches a predetermined differential pressure uniquely determined by the valve closing force (electromagnetic suction force), that is, the target differential pressure ΔPo. Means to change mechanically.

Therefore, the discharge capacity is changed by changing the target differential pressure ΔPo that is uniquely determined by the valve closing force (electromagnetic attraction force) as described above by the control of the control current In, and the actual discharge from the compressor 2 is performed. The discharged refrigerant flow rate can be changed.

Next, the compressor load control according to the degree of acceleration according to this embodiment will be described with reference to FIGS. 3 to 6. In the present embodiment, the compressor load will be described as the compressor torque.

FIG. 3 shows a control routine executed by the air conditioning controller 14 for compressor load (torque) control. At the start of this control routine, the vehicle engine 11 is running and the air conditioner It is assumed that the switch is in the ON state.

First, in step S10, the degree of acceleration is determined. Acceleration is engine control device 1
Based on the vehicle speed and throttle opening or accelerator opening information from 9, the acceleration determination map as shown in FIG. 4 is used (FIG. 4 shows an example in the case of the relationship between vehicle speed and throttle opening). Is). More specifically, in step S10, it is determined from the relationship between the vehicle speed during acceleration and the throttle opening degree whether or not the acceleration corresponds to the acceleration requiring the compressor load control, and whether the acceleration is rapid. Alternatively, the degree of acceleration such as mild acceleration (slow acceleration) is also determined. For example, the example shown in FIG. 4 shows a case where three types of acceleration are performed during traveling in accordance with the vehicle speed indicated by the point P and the throttle opening. When the relationship of the opening degree is located at the point A, it is determined that it does not correspond to the acceleration requiring the compressor load control because it is located below the acceleration determination line L1. In this case, the compressor load (torque) control according to the acceleration of the vehicle is not performed, and the publicly known control according to the temperature state is performed on the compressor 2 (for example, the temperature detected by the temperature sensor 13 is set as the set temperature. The control to do so is performed (step S40).

On the other hand, in the example shown in FIG. 4, when the relationship between the vehicle speed during acceleration and the throttle opening is located at point B or C, the compressor is located above the acceleration determination line L1. It is determined that the acceleration requires load (torque) control, each acceleration degree is determined, and the process proceeds to step S20 in which the compressor torque reduction amount ΔT is determined accordingly.

The compressor torque reduction amount ΔT is determined using a compressor torque reduction amount ΔT determination map similar to the acceleration determination map of FIG. 4 as shown in FIG. This compressor torque reduction amount ΔT determination map is for determining the required compressor torque reduction amount ΔT according to the degree of acceleration,
Illustration (map) of required compressor torque reduction amount ΔT determined by the relationship between vehicle speed during acceleration and throttle opening
It was done. As shown in FIG. 5, a curve (L2, L2,
L3, L4) are drawn along the acceleration determination line L1.

In the example shown in FIG. 5, the required compressor torque reduction amount ΔT in the case of gentle acceleration indicated by point B is 2N.
m, and the required compressor torque reduction amount ΔT in the case of rapid acceleration indicated by point C is 15 Nm.

Both the acceleration determination map shown in FIG. 4 and the compressor torque reduction amount ΔT determination map shown in FIG. 5 both ensure the acceleration of the vehicle and the cooling capacity of the refrigeration cycle apparatus 1. From the viewpoint of
It is stored in the air conditioning controller 14.

When the required compressor torque reduction amount ΔT according to the degree of acceleration is determined in step S20, the compressor control according to the torque is actually performed in step S30.
Proceed to (including steps S31 to S34).

In step S30, first, in step S31, the drive torque T of the current compressor 2 (just before acceleration) is calculated (determined). Here, the drive torque T of the compressor 2 can be calculated by various methods, but in the case of the present embodiment, the high pressure (compressor discharge pressure) detected by the high pressure sensor 18 and indirectly It is calculated based on the control current (control current signal) In representing the compressor discharge capacity and the engine speed.

Next, at step S32, the target compressor torque To is obtained by subtracting the required compressor torque reduction amount ΔT corresponding to the acceleration degree determined at step S20 from the drive torque T of the compressor 2 calculated at step S31. It is determined. Then, in the subsequent step S33, the drive torque of the compressor 2 is the target compressor torque To.
The target control current (target control current signal) Ino for controlling the capacity of the compressor 2 so that
And the high pressure (compressor discharge pressure) detected by the high pressure sensor 18 and the engine speed are determined in an inverse formula.

In step S34, the discharge capacity of the compressor 2 is controlled by the target control current Ino determined in this way, and the compressor 2 is reduced in torque To by a necessary compressor torque reduction amount ΔT corresponding to the acceleration. Driven. Then, thereafter, in order to secure the cooling capacity, the control current In is controlled to gradually restore the discharge capacity of the compressor 2 and return to the start state of this routine to prepare for the next acceleration.

FIG. 6 exemplifies changes in the compressor torque in the control of the compressor 2 as described above. Figure 6
(A) shows the change of the compressor torque in the case of the gentle acceleration represented by the point B in FIG. 5, and FIG. 6 (b) shows the compressor torque of the rapid acceleration represented by the point C in the FIG. Shows changes.

As described above, when the vehicle is accelerated, the required compressor torque reduction amount ΔT corresponding to the degree of acceleration is
Is determined to reduce the load on the engine 11 by driving the compressor 2 with the torque To reduced by the required compressor torque reduction amount ΔT at the start of acceleration by controlling the compressor capacity. By returning the compressor capacity, it is possible to ensure the acceleration of the vehicle and the cooling capacity that matches the acceleration of the refrigeration cycle apparatus 1.

In this embodiment, the compressor 2 capable of stepless capacity control according to the torque is used. However, when the step variable capacity compressor is used, the compression as shown in FIG. The compressor control map can be used to control the compressor according to the degree of acceleration. That is, in the case of gentle acceleration in which the relationship between the vehicle speed during acceleration and the throttle opening in FIG. 7 is above the acceleration determination line L1 and below the curve L5 as indicated by point D, the acceleration is Even in the initial stage of the procedure, the partial displacement operation is performed without reducing the compressor capacity to zero and then the displacement is controlled to be restored, while the relationship between the vehicle speed during acceleration and the throttle opening is indicated by point E. In the case of sudden acceleration that is above the curve L5, the compressor capacity is set to zero in the initial stage of acceleration, and then the partial capacity operation is performed and the capacity is gradually restored. By such control, the drive torque of the compressor is controlled according to the degree of acceleration (in the case of slow acceleration; FIG. 8A, in the case of rapid acceleration; FIG. 8B), and thus detailed above. As in the case of using the compressor 2 capable of stepless capacity control in accordance with the torque, it is possible to ensure the acceleration of the vehicle and the cooling capacity corresponding to the degree of acceleration.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a system including a vehicle refrigeration cycle device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an external variable displacement compressor used in the vehicle refrigeration cycle apparatus according to the embodiment of the present invention.

FIG. 3 is a flowchart showing an operation related to compressor load (torque) control according to an embodiment of the present invention.

FIG. 4 is an acceleration determination map according to an embodiment of the present invention.

FIG. 5 is a compressor torque reduction amount determination map according to an embodiment of the present invention.

FIG. 6 shows changes in compressor torque in compressor control according to an embodiment of the present invention. Figure 6
(A) shows the change of the compressor torque in the case of the gentle acceleration represented by the point B in FIG. 5, and FIG. 6 (b) shows the change of the compressor torque in the case of the rapid acceleration represented by the point C in FIG. Shows changes.

FIG. 7 is a compressor control map according to another embodiment of the present invention (when a step variable displacement compressor is used).

FIG. 8 shows changes in compressor torque in compressor control according to the embodiment when the step variable displacement compressor of the present invention is used. 8A shows a change in compressor torque in the case of slow acceleration represented by point D in FIG. 7, and FIG. 8B shows a compressor torque in the case of rapid acceleration represented by point E in FIG. The change in torque is shown.

[Explanation of symbols]

1 ... Refrigeration cycle device for vehicle air conditioning 2 ... Compressor 3 ... condenser 4 liquid receiver (gas-liquid separator) 5 ... Expansion valve (pressure reducing means) 5a ... Temperature sensing part 6 ... Evaporator 7 ... Air conditioning case 8 ... Refrigerant piping 9 ... Power transmission mechanism 10 ... Belt 11 ... Vehicle running engine (E / G) 12 ... Blower 13 ... Evaporator outlet temperature sensor 14 ... Air-conditioning control device (A / C ECU) 15 ... Electromagnetic capacity control valve (Discharge capacity control mechanism) 16 ... Sensor group for automatic control of air conditioning 17 ... Air conditioning operation panel 18 ... High pressure sensor 19 ... Engine control unit (E / GECU) 19a ... A sensor group for detecting the operating condition of the vehicle engine

Claims (8)

[Claims] 1. A refrigeration cycle apparatus for a vehicle, comprising a variable displacement compressor driven by a vehicle engine, comprising: an acceleration determination means for determining a degree of acceleration of a vehicle; and a determination result of the acceleration determination means. And a control determining means for determining a control pattern of the load of the compressor on the engine, and the capacity of the compressor is determined by the control determining means as the load of the compressor during acceleration of the vehicle. A refrigeration cycle apparatus for a vehicle, which is controlled to have a control pattern. 2. The control determining means determines a necessary reduction amount of the load of the compressor on the engine according to the determination result of the acceleration determining means, and the capacity of the compressor at the start of acceleration of the vehicle. The refrigeration for vehicles according to claim 1, wherein the compressor is controlled so that the load of the compressor is reduced by the required reduction amount, and then the capacity of the compressor is gradually recovered. Cycle equipment. 3. The refrigeration cycle apparatus for a vehicle according to claim 1, wherein the acceleration determining means determines the degree of acceleration of the vehicle based on a vehicle speed and an accelerator opening degree, or a vehicle speed and a throttle opening degree. 4. The control determining means determines a required reduction torque as a required reduction amount of the load of the compressor, and the compressor is a compressor whose capacity is controlled by a control current signal from the outside. A compressor torque is calculated based on the control current signal, the compressor discharge pressure, and the engine speed, and the target compressor torque is determined by subtracting the required reduction torque from the compressor torque. A target control current signal is determined based on the compressor torque, the discharge pressure of the compressor, and the engine speed, and the capacity of the compressor is controlled by the target control current signal at the start of vehicle acceleration. The refrigeration cycle device for a vehicle according to claim 2 or 3. 5. A method for controlling a refrigeration cycle apparatus for a vehicle, comprising a variable displacement compressor driven by a vehicle engine, comprising: a step of determining a degree of acceleration of a vehicle; and a step of determining a result of the determination. And a step of determining a control pattern of the load of the compressor on the engine, and a step of controlling the capacity of the compressor so that the load of the compressor becomes the determined control pattern. Refrigeration cycle device control method. 6. The step of deciding the control pattern includes the step of deciding a necessary reduction amount of the load of the compressor on the engine according to the decision result of the step of deciding the degree of acceleration. The step of controlling the capacity of the compressor controls the capacity of the compressor so that the load of the compressor is reduced by the required reduction amount at the start of acceleration of the vehicle, and then gradually reduces the capacity of the compressor. The method for controlling a refrigerating cycle device for a vehicle according to claim 5, further comprising the step of controlling so as to recover the temperature. 7. The method according to claim 5, wherein the step of determining the degree of acceleration includes the step of determining the degree of acceleration of the vehicle based on the vehicle speed and the accelerator opening, or the vehicle speed and the throttle opening. Method for controlling a vehicle refrigeration cycle device. 8. The step of determining a control pattern includes the step of determining a required reduction torque as a required reduction amount of a load of the compressor, wherein the compressor is capacity-controlled by an external control current signal. A step of calculating a compressor torque based on the control current signal, the discharge pressure of the compressor, and the number of revolutions of the engine, the step of controlling the capacity of the compressor, Determining the target compressor torque by subtracting the required reduction torque from the torque; determining the target control current signal based on the target compressor torque, the discharge pressure of the compressor, and the engine speed. And a step of controlling the capacity of the compressor with the target control current signal at the start of acceleration of the vehicle. .