JPH0133364B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an air conditioner for an automobile using a variable capacity compressor equipped with a variable capacity member that changes the discharge capacity of a heat absorbing medium. The present invention relates to a device that reduces the power required for driving in accordance with the temperature of the blown air.

[Conventional technology]

2. Description of the Related Art Conventionally, a device disclosed in Japanese Utility Model Publication No. 47-39071 is known as a device for reducing the power required to drive a refrigeration cycle (compressor) of an automobile air conditioner in accordance with the temperature of blown air.

In the system disclosed in the publication, the compressor is operated intermittently to bring the air temperature downstream of the evaporator to a set value, and this set value is further changed by operating a temperature control lever. As the temperature control lever is operated from the low temperature side to the high temperature side, the above set value is increased, thereby reducing the operating time of the compressor and saving the power required to drive the compressor.

[Problem to be solved by the invention]

However, in the system disclosed in the above-mentioned publication, the air temperature immediately after the evaporator is adjusted only by intermittent operation of the compressor, and this intermittent operation causes the temperature of the blown air to fluctuate within a considerable range, making passengers feel uncomfortable. It was possible to give.

In addition, in the device disclosed in the above publication, the temperature of the blown air is changed only by temperature control downstream of the evaporator by intermittent operation of the compressor until the temperature control lever reaches a predetermined position, and from the predetermined position, the temperature of the blown air is changed by the temperature control downstream of the evaporator. The temperature of the blown air is changed only by adjusting the action. For this reason, the temperature of the blown air may change suddenly at these switching points, which also poses a problem in that the occupant feels uncomfortable.

In view of the above problems, the present invention reduces the power required to drive the compressor in accordance with the required blowing air temperature, reduces fluctuations in the blowing air temperature, and prevents sudden changes in the blowing air temperature. This was done for the purpose of suppressing this.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an automobile air conditioner in which an air cooling evaporator and a heater whose heating action can be adjusted are arranged in an air conditioning unit, which incorporates a variable discharge capacity mechanism for heat absorption medium. , a refrigeration cycle including a compressor driven by an on-vehicle engine, and having a variable mechanism that changes the amount of heat-absorbing medium passing through the evaporator, thereby making it possible to adjust the cooling effect in the evaporator; commanding means for commanding a blowing air temperature from a low temperature to a high temperature; and increasing the heating action of the heater as the blowing air temperature commanded by the commanding means increases from a low temperature to a high temperature. At the same time, a technical means is adopted in which a control means for reducing the discharge capacity of the compressor by the variable discharge capacity mechanism is provided.

[Effect]

According to the configuration of the present invention as described above, the cooling effect of the refrigeration cycle including the evaporator and the compressor is changed by adjusting the discharge capacity by the variable discharge capacity mechanism of the compressor.

Then, the temperature of the blown air is adjusted by adjusting both the heating action of the heater and the discharge capacity of the compressor in accordance with the blown air temperature commanded by the command means by the control means.

That is, as the temperature of the blown air commanded by the command means increases from low to high, the heating action of the heater is increased and at the same time the discharge capacity of the compressor is decreased to command the blown air temperature. Change according to instructions from the means.

〔Effect of the invention〕

According to the configuration and operation of the present invention described above, as the temperature of the blown air commanded by the command means increases from a low temperature to a high temperature, the discharge capacity of the compressor is reduced. The power required to drive the compressor is reduced by the amount of the reduction. Furthermore, by reducing the discharge capacity, the cooling effect in the evaporator can be adjusted, so it is possible to reduce fluctuations in the temperature of the blown air due to intermittent operation of the compressor. Furthermore, in accordance with the command from the command means, the heating action of the heater and the discharge capacity of the compressor are changed, so instead of adjusting the blown air temperature by intermittent operation of the compressor as in the conventional technology, the heater Sudden changes in the temperature of the blown air can be suppressed by switching to the adjustment of the blown air temperature by the heating effect of the blown air. Further, since fluctuations in the temperature of the blown air are reduced and sudden changes are suppressed, comfortable air conditioning can be performed without causing any discomfort to the occupants.

〔Example〕

An embodiment to which the present invention is applied will be described below.
In the following embodiments, the command means of the present invention is implemented by the operating device 16, and the control means is implemented by a link mechanism and an electric circuit.

In FIG. 1 showing the overall configuration, a compressor 1 is of a variable capacity type, receives rotational power from an on-vehicle engine (not shown) via a clutch 2, causes an internal piston to reciprocate, and discharges and circulates an endothermic medium. . As will be described later, the compressor 1 incorporates a variable capacity member, the position of which is adjusted by a servo motor 3 and a worm gear 4. The servo motor 3 is driven forward and backward by an electric control circuit 6. 5 is a feedback resistor.

A refrigeration cycle including a compressor 1 includes a condenser 7, a receiver 8, an expansion valve 9, and an evaporator 10 as a heat absorber.
It has a vapor compression refrigeration cycle.
The evaporator 10 is installed in a ventilation duct 11 that supplies conditioned air toward the vehicle interior. This evaporator 1
0 is cooled by passage of an endothermic medium, and blower 1
2, heat is removed from the air flow introduced from the vehicle interior or outside the vehicle interior and flowing toward the vehicle interior as shown by the arrow, thereby cooling the vehicle. Here, the cooling capacity changes depending on the flow rate of the endothermic medium passing through the evaporator 10.
The cooled airflow is appropriately reheated by an air mix type reheater consisting of an air mix damper 13 and a heater 14 for radiating heat from engine cooling water, and then sent to the passenger compartment.

Next, the configuration and operation of the variable displacement compressor 1 will be explained in detail.

2 to 4, a shaft 101 is connected to an automobile engine serving as a drive source via an electromagnetic clutch 2 shown in FIG. 1 and a V-belt (not shown), and is rotated by the driving force of the engine. 102 is a swash plate that rotates together with the shaft 101, and the rotation of this swash plate 102 is caused by the rotation of the shaft 101.
3 to cause the piston 104 to reciprocate. 1
05, 106 is a housing, and the piston 10
It has a cylinder part 107 that supports the reciprocating motion of the four cylinders, and is divided into two parts, the front and the rear, and is die-cast from aluminum or the like. 108 is a suction passage chamber formed within the housings 105 and 106. As shown in FIGS. 3 and 4, the cylinder portion 107 is located at five locations 107a, 107b, 1
07c, 107d, and 107e are formed, and only the lowermost cylinder parts 107c and 107d are spaced at an angle of 88°, and the spaces between the other cylinder parts are all 68°. . Further, the suction passage chamber 108 is formed between each cylinder part 107 as shown in FIG. It communicates with the outlet side refrigerant circuit of No. 10.

Reference numerals 109 and 110 denote side housings, which are disposed outside the housings 105 and 106 with valve plates 111 and 112 in between. A suction chamber 113 is formed in a portion of the side housings 109 and 110 that directly communicate with each other through a suction side communication hole (not shown), and a portion of the side housings 109 and 110 that faces the piston 104 on the inner periphery of the suction chamber 113 is formed. A discharge chamber 114 is formed at the position. This discharge chamber 114 is connected to the housing 10 through the discharge side communication holes (not shown) of the valve plates 111 and 112.
It communicates with the discharge passage chamber 114a (FIG. 4) of No. 5,106. 115, 116 are valve plates 11
1 , 112 and the housings 105 , 106 are disc-shaped elastic metal plates made of elastic metal, such as spring steel, and a U-shaped (not shown) A notch is provided to form a suction valve.

In addition, the housings 105 and 106, the side housings 109 and 110, and the valve plate 11
1 and 112 are integrally connected by a through bolt 117, and the through bolt 117 passes through the suction passage chamber 108 within the housings 105 and 106 to facilitate assembly.

118 and 119 are radial bearings using normal needle bearings, and housing 1
An outer race is fixed to 05 and 106 to rotatably hold the shaft 101. 1
Thrust bearings 20 and 121 are located between the center portions of the housings 105 and 106 and the swash plate 102, so that the force applied to the swash plate 102 in the thrust direction (axial direction), that is, the swash plate 102
This supports the reaction force received when 04 is communicated back and forth.

Reference numeral 122 denotes a shaft seal, which is located on the drive source side (in other words, on the electromagnetic clutch 2 side) of the side housings 109 and 110.
It is located between the compressor 9 and the shaft 101 to maintain airtightness so that the refrigerant gas and lubricating oil inside the compressor do not leak to the outside.

Reference numeral 123 denotes a holder for the servo motor 3, which is fixed to the rear side housing 110 with screws 124. The worm gear 4 of the servo motor 3 is the third
As shown in the figure, it is connected to an operating shaft 126 by a worm gear 125. This operating shaft 126 is arranged between the rear valve plate 112 and the front valve plate 111 by utilizing the space between the lowermost cylinder parts 107c and 107d, and is located between the valve plate 111 of the operating shaft 126.
Spur gears 127 and 128 are attached to portions adjacent to wheels 1 and 112, respectively.

Reference numerals 129 and 130 are annular variable rings that constitute variable capacity members;
9,130 is housing 105,106,
It is disposed in a cylindrical space provided on the outer periphery of the cylinder portion 107 so as to be concentric with the compressor drive shaft 101 . The rotational force of the operating shaft 126 is applied to the variable rings 129, 130 through the spur gears 127, 128.
The rotation is transmitted through teeth 129a, 130a provided on the inner periphery of the variable rings 129, 130.

Two bypass holes 131a and 131b are provided in the wall surface of each cylinder portion 107 at positions closest to the variable rings 129 and 130, and shaft holes 131a and 131b are provided in the bypass grooves 132a and 132b and in the variable rings 129 and 130, respectively. Bypass groove 133 arranged parallel to 101 and variable ring 1
The inner circumferential surfaces of the compressors 29 and 130 communicate with a bypass port 135 formed in the housings 105 and 106 through a bypass groove 134 provided all around the center side of the compressor.
Furthermore, this bypass port 135 is connected to the housing 10.
5, 106 is formed so as to be electrically connected to the suction passage chamber 108 provided in the suction passage chamber 106.

In this embodiment, the bypass holes 131a and 131b drilled in the wall surface of the cylinder 107 are arranged at positions that divide the cylinder volume into three equal parts, and either only the port 131b on the center side of the compressor, or both the ports 131a , 131b are arranged to face the bypass grooves 132a, 132b in accordance with the rotation angle of the variable rings 129, 130 (see FIGS. 5 and 6).

Further, the bypass grooves 132a, 132b are connected to the five cylinders 107a, 107b, 107c, 107.
d and 107e, respectively, as shown in FIG.
The cylinders 107 are provided with different lengths in the circumferential direction of the cylinder 107 and communicate with the suction passage chamber 108 according to the rotation angle of the variable rings 129 and 130.
It has been devised so that the number of That is, in the case of this embodiment, when the rotation angle is 0°, all the bypass holes 131a and 131b (20 holes in total) are located directly opposite the bypass grooves 133 of the variable rings 129 and 130, and this bypass groove 133, a bypass groove 134, and a bypass port 135 of the housings 105, 106 to communicate with the suction passage chamber 108, so that the cylinder volume that performs net compression work is minimized. When the rotation angle is 4 degrees, the bypass hole 1 provided in the cylinder 107e
Only the bypass hole 31a is not in communication with the bypass groove 132a, and the remaining bypass holes 131a and 131b are both in communication with the suction passage chamber 108.

Thereafter, as the rotation angle increases by 4 degrees such as 8 degrees, 12 degrees, etc., the number of bypass holes that do not communicate with the suction passage chamber 108 increases one by one, and when the rotation angle is 36 degrees,
Bypass hole 131 provided in cylinder 107a
Only the bypass holes 131a and 131b are in communication with the suction passage chamber 108 through the bypass groove 132b, and the others are not in communication, and when the rotation angle reaches 40 degrees, all the bypass holes 131a and 131b are closed, and due to compression work. The cylinder volume of is maximum. This variable ring 1
The relationship between the rotation angle of 29,130 degrees and the cylinder volume that performs net compression work is shown in Figure 8, and the cylinder volume is finely adjusted in 10 steps between the maximum volume vmax and 1/3 vmax. Can be controlled. This means that the power consumption in the compressor and the evaporator 1
This shows that the cooling capacity of 0 is controlled in 10 stages.

The rotational positions of the variable rings 129, 130 can be detected as electrical signals by the potentiometer 5 of the position detection device 5'. That is, the worm gear 125 formed on the end surface of the operating shaft 126 is the operating gear 2 of the position detection device 5'.
41, and the operating shaft 12
6 (worm gear 125), the potentiometer resistance value of the position detection device 5' is varied,
As a result, an electric signal determined depending on the position of the variable rings 129, 130 is output. The position detection device 5' is fixed to the side housing 110 with screws 243 via a stay 242 formed on the side surface thereof. Note that storage grooves are formed in the side housing 110 at a portion where the position detection device 5' is held and at a portion where the aforementioned servo motor 3 is held, so that the servo motor 3 and the position detection device 5' are etc., and the side housing 11
The servo motor 3 and the like are designed not to protrude too much from the zero surface. Although not shown, the servo motor 3, worm gears 4, 125, position detection device 5', etc. are covered with a cover (not shown) to prevent dust.

Next, to explain the operation of only one part of the swash plate compressor, the electromagnetic clutch 2 is connected and the shaft 1 is connected.
01 and the swash plate 102 begin to rotate, the refrigerant gas vaporized in the evaporator 10 flows through the housing 105,
It is introduced into the suction passage chamber 108 from an inlet (not shown) provided in the valve plate 111,
The suction chamber 11 of the front and rear side housings 109, 110 passes through the suction side communication hole 112 (not shown).
Flows into 3. The piston 10 reciprocates within the cylinder portion 107 as the swash plate 102 rotates.
4 is the suction process, refrigerant gas, which is an endothermic medium, is sucked into the cylinder portion 107 from the suction ports in the valve plates 111 and 112 through the suction valves formed in the elastic metal plates 115 and 116. Next, when the piston 104 moves to the compression stroke, the suction port is closed by the suction valve, and the cylinder portion 10
The refrigerant gas in 7 is compressed by the piston, and passes through the discharge ports of valve plates 111 and 112 and discharge valves (not shown) to the side housings 109 and 1.
10 is discharged to the discharge chamber 114 in the housing 105, 106, and then the discharge passage chamber 1 in the housing 105, 106 is discharged again from the discharge side communication hole (not shown) of the valve plate 111, 112.
The refrigerant gas flows into the housing 14a and becomes high temperature and high pressure during the compression stroke of the piston 104.
The water is sent to the condenser 7 from unillustrated discharge ports 05 and 106.

Therefore, the discharge flow rate of the refrigerant gas is controlled by variable rings 129 and 130 corresponding to the rotation of the servo motor 3.
The evaporator 10 can be changed in 10 steps depending on the rotation angle of
The cooling capacity can be adjusted.

In FIG. 1, a thermistor 15 is installed downstream of the evaporator 10 to sense the temperature of the secondary air cooled by the evaporator 10. This thermistor 15 exhibits an electrical resistance depending on the temperature of the secondary air that is the atmosphere. The thermistor 15, the potentiometer 5, and a variable resistor 17 interlocked with an operating device 16 for temperature adjustment operated by a passenger are connected in series on the input side of the electric control circuit 6. The voltage V ₁ at that connection point is input to the electrical control circuit 6, which determines its operating characteristics and controls the servo motor 3.
Determine whether it is forward or reverse.

The operating device 16 is configured as a rotatable lever, and its operating amount is configured to firstly change the opening degree of the air mix damper 13 via a link mechanism, and secondly to change the opening degree of the air mix damper 13 via a link mechanism 19. to displace the sliding contact 17c of the variable resistor 17. The variable resistor 17 is composed of a sliding resistor 17a and an electrode 17b, and exhibits electrical resistance in a predetermined pattern through contact with the sliding contact 17c.
5 is connected.

Electrical control circuit 6 drives servo motor 3 in response to voltage signal _V1 . Here, the role of the electric control circuit 6 is to detect the temperature of the secondary air detected by the thermistor 15, and control the rotation of the servo motor 13 according to the balance between this and the set reference value of the variable resistor 17. , to determine the capacity of the compressor 1. Generally speaking, if the temperature of the secondary air decreases, the compressor capacity will decrease, and the decrease in the resistance value of the variable resistor 17 due to the movement of the temperature controller from A to C (movement to the high temperature side) will decrease the compressor capacity. This will reduce the

In FIG. 9 showing details of the electric control circuit 6,
The signal voltage V ₁ is applied to two comparators 20 and 21 with different operating points (thresholds), and the voltages V ₂ ,
V ₃ is compared with its operating point. Logic level signals indicating comparison results are sent to drive transistors 24a to 24 through output stages each consisting of a transistor.
c, 25a-25c. comparator 20,
21 acts as a so-called window comparator, and when V ₁ > V ₂ , the drive transistors 24a to 2
4c is activated, when V ₁ <V ₃ the drive transistors 25a to 25c are activated, and when V ₂ <V ₁ <V ₃ the two driving transistors are deactivated.

In other words, when the temperature of the secondary air detected by the thermistor 15 is high, the servo motor 3 rotates in a direction to increase the capacity of the compressor 1, and vice versa when the temperature of the secondary air becomes low. Servo motor 3
rotates to reduce the capacity of the compressor 1, and eventually the variable resistor 17 and thermistor 1
The voltage indicating the ratio of the resistance value with 5 is the threshold value V ₂ , V ₃
Adjust the capacity of the compressor so that it is within the range. Note that the potentiometer 5 functions as a minor loop feedback and prevents hunting in the system.

Incidentally, the relationship between the operation amount of the temperature control device 16, the opening degree of the air mix damper 13, and the temperature of the secondary air of the evaporator 10 is set as shown in FIG. In other words, air mix damper 13
The opening changes in a linear relationship with the displacement of the operating device 16 toward the heating side (in the direction of the arrow), but on the other hand, the resistance value R of the variable resistor 17 changes at the maximum cooling position A ₁
to intermediate position B ₁ , indicating that the compressor capacity is gradually reduced during this period to reduce the cooling capacity. In addition, the temperature T ₀ of the secondary air changes depending on the position of the operating device 16 on the cooling side from the intermediate position B ₁ in accordance with the change in the resistance value R, and becomes a constant value on the heating side from the intermediate position B ₁ . Reduces cooling effect.

Although one embodiment of the present invention has been described below, the present invention can also be applied to the following modifications.

(1) Regarding the compressor 1, in the above embodiment, the bypass holes 131a and 131b of the cylinder 107 were communicated with the suction passage chamber 108 via the bypass grooves 132a, 132b, 133, 134, etc.; Any space may be used as long as the pressure is lower than the internal pressure, in other words, the space has suction pressure inside.Depending on the shape of the compressor, this communication may be between the suction chamber 113 and the crank chamber (rotation of the swash plate 2). space) or in another cylinder 107 that is on the suction stroke.

(2) Although a 10-cylinder swash plate compressor is used in the above embodiment, it goes without saying that any swash plate compressor having a plurality of cylinders may be used. Further, in the above embodiment, the variable ring 12
9 and 130 are disposed within the cylindrical space on the outer periphery of the housings 105 and 106, but it goes without saying that they may also be disposed between the compressor drive shaft 101 and each cylinder 107.

(3) As long as the compressor 12 is of a variable capacity type, it is not limited to a swash plate type, and other types such as a vane type can be used.

(4) The variable capacity member is not limited to the variable rings 129, 130, and can be changed into various forms depending on the type of compressor, etc.

(5) As the drive device, in addition to the electric servo motor 3, a combination of a negative pressure diaphragm mechanism and a link mechanism, etc. can also be used.

(6) In the above example, the air temperature immediately after the evaporator was detected as the secondary air temperature of the evaporator 10, but in addition to this, the air temperature immediately after the evaporator was detected. Surface temperature may also be detected.
Furthermore, the evaporator refrigerant pressure may be detected instead of the evaporator refrigerant temperature.

(7) The structure of the link mechanism 18 that transmits the displacement of the operating device 16 or the variable resistance pattern may be modified as shown in FIGS. 11 and 12 as necessary.

According to the characteristics shown in Fig. 11, in the low temperature range, the blowing air temperature is changed only by a decrease in the compressor capacity (reduction in cooling capacity) due to a decrease in the resistance value R of the variable resistor 17, and in the high temperature range, the air The temperature of the blown air is changed only by increasing the opening degree of the mix damper 13. Further, in the intermediate range, the temperature of the blown air is changed by both a decrease in the compressor capacity due to a decrease in the resistance value R and an increase in the opening degree of the air mix damper 13.

Thereby, the temperature of the blown air can be changed in response to the amount of lever operation without drastically changing the temperature suddenly.

Moreover, as shown in the characteristics shown in FIG. 12, the resistance value R of the variable resistor 17 is
and the opening degree of the air mix damper may be changed.

(8) By detecting the displacement of the operating device 16 over its entire operating range with a variable resistor, etc., and processing the electrical signal with an electrical circuit, the servo motor 3
and the actuator of the air mix damper 13 may be controlled.

(9) A digital computer, a so-called microcomputer, may be used as part of the electric circuit.

As described above, in the present invention, by changing the capacity of the variable capacity compressor and also changing the heating capacity, an excellent effect is exhibited in that sudden changes in power consumption and temperature of the blown air can be prevented.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of the apparatus of the present invention, and FIG. 2 is a cross-sectional view showing one embodiment of the compressor 1 used in the present invention, showing the shape taken along the line DD in FIG. 3. FIG. 3 is a side view of the compressor. Figure 4 is A of Figure 7.
-A cross-sectional view showing the relationship between the bypass hole and the bypass groove of the variable ring. FIG. 5 is a diagram showing the positional relationship of each bypass groove provided in the variable ring, and is a developed view in the direction of arrow B--B in FIG. 6. 6th
The figure is a sectional view taken along the line C-C in FIG. 5, and FIG. 7 is a sectional view showing the shape of the bypass groove corresponding to each cylinder.
Fig. 8 is an explanatory diagram showing the relationship between the rotation angle of the variable ring and the net cylinder volume that performs compression work, Fig. 9 is an electrical wiring diagram showing one embodiment of the electric control circuit 6 used in the present invention, and Fig. 10. 11 is an operating characteristic diagram for explaining the operation, and FIGS. 11 and 12 are operating characteristic diagrams for explaining a modified embodiment. 1... Variable capacity compressor, 2... Electromagnetic clutch, 3... Servo motor, 5... Potentiometer, 6... Electric control circuit, 10... Evaporator (heat absorber), 11... Ventilation duct , 13... air mix damper, 14... heater, 15... secondary air temperature detection thermistor, 16... temperature control operator,
17...variable resistance, 18...link mechanism.

Claims (1)

[Scope of Claims] 1. An automobile air conditioner in which an air cooling evaporator and a heater whose heating action can be adjusted are arranged in an air conditioning unit, which has a built-in variable discharge capacity mechanism for heat absorbing medium, A refrigeration cycle that includes a driven compressor and that allows the variable mechanism to change the amount of endothermic medium passing through the evaporator to adjust the cooling effect in the evaporator, and the temperature of the air to be blown out from the air conditioning unit. commanding means for commanding the temperature from a low temperature to a high temperature; and as the temperature of the blown air commanded by the commanding means increases from a low temperature to a high temperature, the heating action of the heater is increased and at the same time the discharge capacity is increased. An air conditioner for an automobile, comprising: a control means for reducing the discharge capacity of the compressor by a variable mechanism. 2. The control means includes: heating control means that increases the heating action of the heater as the temperature of the blown air commanded by the command means increases from a low temperature to a high temperature; and a heating control means commanded by the command means. The vehicle according to claim 1, further comprising a capacity control means for reducing the discharge capacity of the compressor as the temperature of the blown air increases from a low temperature to a predetermined intermediate temperature. Air conditioner. 3. The control means: heating control means for increasing the heating action of the heater as the temperature of the blown air commanded by the command means increases from a predetermined first intermediate temperature toward a high temperature; Capacity control means for reducing the discharge capacity of the compressor as the temperature of the blown air commanded by the command means increases from a low temperature toward a second intermediate temperature higher than the first intermediate temperature. An air conditioner for an automobile according to claim 1, comprising: an air conditioner for an automobile according to claim 1; 4. The capacity control means: a cooling degree control means that controls the discharge capacity variable mechanism to change the discharge capacity of the compressor in order to make the degree of cooling of the evaporator a predetermined target value; and the command means. Correction means for reducing the discharge capacity of the compressor by correcting the target value of the capacity control means so that the degree of cooling decreases as the commanded blowing air temperature increases from a low temperature to a high temperature. An air conditioner for an automobile according to claim 2 or 3, characterized by comprising: