JP3368718B2 - Air conditioner - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner for controlling the degree of air cooling in an evaporator by using an internal variable capacity compressor configured to change its capacity according to a cooling load. The present invention relates to an air conditioner having a function of controlling the cooling degree by a capacity change according to a cooling load while operating the compressor, and a function of controlling the cooling degree by repeatedly operating and stopping the compressor.

[0002]

2. Description of the Related Art According to an example of the prior art of an air conditioner as described above, the capacity of the compressor changes according to the cooling load, and this change in capacity causes the air temperature after passing through the evaporator to reach a substantially predetermined temperature ( For example, the temperature is controlled to be constant at 0 ° C to 1 ° C. Then, when the capacity becomes the minimum (for example, 20%), the cooling capacity still remains, and when the air temperature after passing through the evaporator becomes equal to or lower than the predetermined temperature, control for repeatedly operating and stopping the compressor (hereinafter , On / off control) to prevent frost on the evaporator.

[0003]

In the case of this prior art,
If the air temperature after passing through the evaporator falls below the above specified temperature,
It has been newly found through experiments and studies by the present inventors that the power of the compressor may increase due to switching to the on / off control. Less than,
This problem will be described in detail with reference to FIG.

FIG. 8 shows that the cooling capacity at the point where the capacity control of the compressor starts (hereinafter referred to as the control start point) is Q0, the compressor power is L0, and the ratio of the actual cooling capacity Q to this cooling capacity Q0 (Q / Q0) and the ratio of the actual compressor power L to the compressor power L0 (L / L0),
The figures show the case of performing the capacity control and the case of performing the on / off control (the capacity at this time is fixed at 100%). That is, the capacity of the compressor is controlled when the cooling capacity ratio Q / Q0 is in the range of 1 or less.

As can be seen from FIG. 8, when the cooling capacity ratio Q / Q0 is less than or equal to Q1, the compressor power ratio L / L0 is better when the on / off control is performed than when the capacity control is performed. When the cooling capacity ratio Q / Q0 is Q1 or more, the power ratio L / L0 of the compressor is smaller when the capacity control is performed than when the on / off control is performed.

On the other hand, in the above-mentioned prior art, when the air temperature after passing through the evaporator becomes equal to or lower than the predetermined temperature, the on / off control is surely performed. That is, if the cooling capacity ratio Q / Q0 at this time is an arbitrary point (for example, Q2) of Q1 or more, capacity control is performed when the cooling capacity ratio Q / Q0 is Q2 or more, and on / off control is performed when Q2 or less. Will be done.

Thus, when the cooling capacity ratio Q / Q0 is switched to the on / off control within the range of Q2 or less, Q1≤Q / Q
In the range of 0≤Q2, the compressor power ratio L / L0 becomes large as compared with the case where the capacity control is performed. Therefore, in the present invention, in an air conditioner that performs both capacity control and on / off control of an internal variable capacity compressor, the cooling capacity ratio Q / Q0 is Q.
The purpose of this is to improve the power saving effect of the compressor by performing on / off control when it is 1 or less and capacity control when Q / Q0 is Q1 or more.

[0008]

Means for Solving the Problems The present inventors have conducted various studies as described below in order to achieve the above object. Depending on the load on the high-pressure side of the refrigeration cycle, the number of revolutions of the compressor, or the like, the control start point in FIG.
0 and L0 deviate. That is, since the cooling capacity ratio Q / Q0 changes depending on the above conditions, it is extremely difficult to obtain the cooling capacity ratio Q / Q0 as a fixed value.

Therefore, the inventors of the present invention have noticed that the cooling capacity ratio Q / Q0 decreases as the operating rate of the compressor (ratio of operating time of the compressor to the total operating rate of the compressor) decreases. As a result of conducting an actual experiment by anticipating that there is a certain relationship between the operating rate and the cooling capacity ratio Q / Q0, the data shown in FIG. 9 were obtained. From the data of FIG. 9, the operating rate φ and the cooling capacity ratio Q /
It turned out that Q0 is almost the same.

Next, the inventors of the present invention conducted extensive studies on a method of estimating the operating rate φ. As a result, the higher the heat load of the air passing through the evaporator, the greater the operating rate φ, and the refrigerant capacity of the evaporator (for example, the refrigerant flow rate).
Paying attention to the fact that the operating rate φ becomes smaller as the value becomes larger, it is expected that the operating rate φ can be expressed by the following Equation 1, and then the following Equation 2 is given as a specific example of the estimated operating rate φa. I was

[0011]

[Equation 1] Estimated operating rate φa = (load on air side of evaporator) /
(Evaporator refrigerant capacity)

[0012]

[Equation 2] Estimated operating rate φa = CVa (Ta1-Ta2) / Nc (C: constant, Va: air flow through evaporator, Ta1: air temperature at evaporator inlet, Ta2: air temperature at evaporator outlet, Nc: compressor rotation Number) Then, the estimated operating rate φa calculated by Equation 2 above.
As a result of actually conducting an experiment on the relationship between and the actual operating rate φ, the data shown in FIG. 10 were obtained. And this Figure 1
From the data of 0, it was found that there is no problem in assuming that the estimated operating rate φa calculated based on the above-mentioned mathematical formula 2 is almost the same as the actual operating rate φ.

In FIG. 10, the capacity of the compressor is 100%.
In the experimental data when the on / off control of the compressor is performed in the above condition, the circles in the figure indicate that the air temperature (Ter) after passing through the evaporator is 3 ° C-4 ° C as shown in Fig. 11 (a). When controlled so as to turn on and off, the triangular mark in the figure is shown in FIG.
As shown in, the case where Ter is controlled so as to turn on and off at 10 ° C to 11 ° C is shown.

As a result of the above examination, the present inventors newly found that if the estimated operating rate φa is obtained in accordance with the idea of the above-mentioned mathematical expression 1, the cooling capacity ratio Q / Q0 can be substituted with this estimated operating rate φa. I found it. The present invention has been made on the basis of the results of the above-described various studies. The characteristic feature of the present invention is that in the invention according to claim 1, a compressor (2) for sucking, compressing and discharging a refrigerant, A condenser (3) for condensing the refrigerant discharged by the compressor (2), a decompression means (5) for decompressing the refrigerant from the condenser (3), and an evaporation for evaporating the refrigerant from the decompression means (5). A refrigeration cycle (1) each equipped with an air conditioner (6), an air blower (9) for generating an air flow, the air generated by this air blower (9) is introduced into the room, and the evaporator (6) An air conditioner comprising: an air passage (8) provided in the air conditioner; and a cooling degree detecting means (11) for detecting the degree to which the evaporator (6) cools the air in the air passage (8). The capacity of the compressor (2) depends on the cooling load. While being configured as an internal variable displacement compressor of this compressor (2), the actuation of the compressor (2), it is connected to switching means (12) for switching a stop, the compressor (2)
Estimated operating rate calculating means (step 220) for calculating the estimated operating rate of
0) the estimated operating rate (φa) is larger or smaller than the predetermined operating rate (φ1), the estimated operating rate determining means (step 230) and the estimated operating rate determining means (step 230). , The estimated operating rate (φ
A first compressor control means (step 240) for controlling the switching means (12) so as to operate the compressor (2) when it is determined that a) is larger than the predetermined operating rate (φ 1). ) And the estimated operating rate determination means (step 2)
30) determines that the estimated operating rate (φa) is smaller than the predetermined operating rate (φ1), the compressor (according to the cooling degree detected by the cooling degree detecting means (11)). An air conditioner comprising a second compressor control means (steps 250 to 330) for controlling the switching means (12) so as to operate or stop 2).

According to a second aspect of the present invention, in the air conditioner according to the first aspect, of the air in the air passage (8), air for detecting the heat load of the air passing through the evaporator (6). Side load detection means (10, 11, step 21)
0) and refrigerant side capacity detecting means (51, step 210) for detecting the cooling capacity of the refrigerant flowing in the evaporator (6).
And the estimated operating rate calculation means (step 220)
Is the estimated operating rate (φa) with respect to the capacity detected by the refrigerant side capacity detecting means (51, step 210),
The air side load detection means (10, 11, step 21)
0) is calculated as the ratio of the detected load.

According to a third aspect of the invention, in the air conditioner according to the second aspect, the air side load detecting means (1
0, 11, step 210) passes through the evaporator (6) based on the product of the air volume passing through the evaporator (6) and the temperature difference of the air before and after the evaporator (6). It is characterized in that it is configured to detect the heat load of air.

Further, in the invention according to claim 4, in the air conditioner according to claim 2 or 3, the refrigerant side capacity detecting means (51, step 210) is based on the number of revolutions of the compressor (2). The cooling capacity of the refrigerant flowing through the evaporator (6) is detected.
According to a fifth aspect of the present invention, in the air conditioner according to any one of the first to fourth aspects, a rotation speed detection means (51) for detecting the rotation speed of the compressor (2) and the rotation speed detection means. The estimated operation rate determining means (step 230) is provided with a predetermined operation rate determining means for determining the predetermined operation rate (φ 1) as a larger value as the compressor rotational speed detected by (51) becomes higher. The estimated operating rate (φ calculated by the estimated operating rate calculating means (step 220)
a) is configured to determine whether it is larger or smaller than the predetermined operating rate (φ1) determined by the predetermined operating rate determining means.

According to a sixth aspect of the invention, in the air conditioner according to any one of the first to fifth aspects, the second
The compressor control means (steps 250 to 330) of the switching means for stopping the compressor (2) when the cooling degree detected by the cooling degree detecting means (11) is larger than a predetermined cooling degree. (12) is controlled, and when the detected cooling degree is smaller than the predetermined cooling degree, the switching means (12) is controlled so as to operate the compressor (2). Characterize.

Further, the reference numerals in the parentheses of the above-mentioned means indicate the corresponding relations with the concrete means of the embodiments described later.

[0020]

According to the invention of claims 1 to 6, instead of the cooling capacity ratio which is very difficult to obtain, the operating rate of the compressor which is almost the same value as this cooling capacity ratio is estimated and operated. Estimate by the rate calculation means. When the estimated operating rate is larger than the predetermined operating rate (φ1 in FIG. 8), control (capacity control) by the first compressor control means is performed. In this case, since the compressor is in the operating state, the capacity of the compressor changes according to the cooling load at that time, and due to this change in capacity, the air flowing in the air passage is cooled to almost a predetermined temperature by the evaporator, Guided indoors.

On the contrary, when the estimated operating rate is smaller than the predetermined operating rate, control (on / off control) by the second compressor control means is performed. In this case, the compressor is operated or stopped according to the cooling degree detected by the cooling degree detecting means. That is, for example, when the detected cooling degree is higher than the predetermined cooling degree, the compressor is stopped to lower the air cooling degree in the evaporator, and when the detected cooling degree is lower than the predetermined cooling degree, the compressor is stopped. Activate to increase the degree of air cooling in the evaporator. As a result, the air flowing in the air passage is cooled to a substantially predetermined temperature by the evaporator and introduced into the room.

As described above, according to the present invention, when the estimated operating rate is larger than the predetermined operating rate, that is, the cooling capacity ratio Q /
When Q0 is Q1 or more, control (capacity control) by the first compressor control means is performed, and when the estimated operating rate is smaller than the predetermined operating rate, that is, when the cooling capacity ratio Q / Q0 is Q1 or less, the second operation is performed. Since the control (on / off control) is performed by the compressor control means, the power ratio of the compressor can be minimized.

As a result of experiments conducted by the inventors of the present invention, it was found that the predetermined operating rate becomes larger as the rotation speed of the compressor becomes higher. Therefore, as in the invention described in claim 5, the predetermined operation rate determining means determines the predetermined operation rate as a larger value as the compressor rotation speed becomes higher, and the estimated operation rate determining means determines the predetermined operation rate. By performing the operation based on the predetermined operating rate determined by the rate determining means, the power ratio of the compressor can always be minimized regardless of the rotation speed of the compressor.

[0024]

EXAMPLES Next, examples of the present invention will be described. FIG. 1 is an overall configuration diagram of this embodiment. The refrigeration cycle 1 according to the present embodiment is installed in an automobile, and includes a compressor 2 that sucks, compresses, and discharges a refrigerant, and a condenser that condenses the refrigerant from the compressor 2 by heat exchange with outside air. Three
And a gas-liquid separator 4 for separating the refrigerant from the condenser 3 into gas and liquid and temporarily storing the excess refrigerant in the refrigeration cycle 1.
And a decompression means 5 for decompressing the liquid refrigerant from the gas-liquid separator 4.
(Specifically, an expansion valve) and an evaporator 6 for evaporating the low-pressure refrigerant from the pressure reducing means 5 by heat exchange with the air in the air conditioning duct 8 are respectively connected by a refrigerant pipe 7. is there.

The evaporator 6 is arranged in an air conditioning duct 8 which guides the air inside the vehicle compartment or the outside air into the vehicle compartment. Further, on the air upstream side of the air conditioning duct 8, a blower means 9 for generating an air flow in the air conditioning duct 8 is provided. This blower 9 is provided with an air conditioning control device 20 described later.
(Hereinafter, referred to as ECU. See FIG. 3). The air-blowing driving unit 9a (specifically, a blower motor) is controlled, and the fan 9b that is rotated by the driving of the air-blowing driving unit 9a.

In the air-conditioning duct 8, a detection means 10 (hereinafter, referred to as a pre-evaporator temperature sensor) for detecting the temperature of the air immediately before passing through the evaporator 6 is provided at a portion of the evaporator 6 immediately upstream of the air. ) Is provided, and a detection means 11 (hereinafter, referred to as “post-evaporator temperature sensor”) that detects the temperature of the air immediately after passing through the evaporator 6 is provided at a portion of the evaporator 6 immediately downstream of the air.

Although not shown in the figure, a heating means for reheating the cold air passing through the evaporator 6, a temperature adjusting means for adjusting the heating degree of the heating means, and the like are arranged in the air conditioning duct 8. Further, at the air downstream end of the air conditioning duct 8, a face outlet for blowing air to the upper half of the passenger in the passenger compartment, a foot outlet for blowing air to the feet inside the passenger compartment, and a defroster outlet for blowing air on the inner surface of the windshield are formed. There is.

By the way, the compressor 2 has an electromagnetic clutch 1.
It is connected to 2. The compressor 2 is connected to the ECU 20.
When the electromagnetic clutch 12 is energized based on the control signal from (FIG. 3), the power of the automobile engine 13 is transmitted to compress the refrigerant of the refrigeration cycle 1, and conversely the electromagnetic clutch 12 is deenergized. When the engine 13
Is cut off and the refrigerant compression function is lost.

Next, the internal structure of the compressor 2 will be briefly described with reference to FIG. The internal structure described below is disclosed in Japanese Patent Application Laid-Open No. 4-301189, so detailed description will be omitted. In the housing 31 of the compressor 2,
A rotary shaft 32 that rotates with the rotation of the engine 13 is provided, and a swash plate 33 is provided so as not to rotate together with the rotary shaft 32. When the cylinder case 34 rotates together with the rotary shaft 32,
A sliding member 36 provided on one end side of the piston 35 slides along the surface of the swash plate 33, whereby the piston 35 reciprocates in the cylinder chamber 37 in the left-right direction in the drawing. That is, the stroke of the piston 35, that is, the discharge capacity of the compressor 2 changes according to the inclination of the swash plate 33.

A part of the swash plate 33 is a holder 38.
It is sandwiched by and the piston 39. Here, due to the elastic force of the coil spring 40, the holder 38 is
A force for pushing the above-mentioned part of the swash plate 33 to the right in the drawing acts,
In addition, the control pressure P in the control pressure chamber 41 is applied to the piston 39.
A force that pushes the above-mentioned part of the swash plate 33 to the left in the drawing acts by c. That is, the inclination of the swash plate 33 is determined by the elastic force and the control pressure Pc.

By the way, in the control pressure chamber 41, the low pressure Ps on the side of the evaporator 6 is introduced through the communication passages 42 and 43, and the high pressure Pd which has become high by the compressor 2 itself is communicated with the communication passage 42. , 44. Further, a valve body 45 is provided in the communication portion between the communication passages 42 and 43, and the position of the valve body 45 changes, and the passage area in this communication portion changes, so that the control pressure Pc changes. Is configured to.

When the cooling load is large, the low pressure Ps becomes high, and the diaphragm 46 is pushed downward in the figure. Then, the valve body 4 is passed through the rod 47.
5, the control pressure Pc in the control pressure chamber 41 becomes high. If the control pressure Pc becomes higher, the piston 39 increases the force for pushing the above-mentioned part of the swash plate 33 to the left side in the figure, and as a result, the inclination of the swash plate 33 increases and the discharge capacity of the compressor 2 increases. growing.

On the contrary, when the cooling load is small, the low-pressure pressure Ps becomes low, so that the diaphragm 46 is pushed upward in the figure. Then, the valve element 45 is raised upward in the figure via the rod 47, so that the control pressure P in the control pressure chamber 41 is increased.
c becomes low. Therefore, as a result, the inclination of the swash plate 33 becomes smaller and the discharge capacity of the compressor 2 becomes smaller. As described above, the compressor description 2 of this embodiment is a so-called internal variable capacity compressor in which the discharge capacity automatically changes according to the cooling load, and such an internal variable capacity compressor is used. As a result, the air temperature after passing through the evaporator 6 is controlled to be substantially constant at a predetermined temperature (for example, 0 ° C. to 1 ° C.).

Next, the configuration of the control system of this embodiment will be described with reference to FIG. The ECU 20 includes, in addition to the pre-evaporator temperature sensor 10 and the post-evaporator temperature sensor 11, a rotation speed sensor 51 that detects the rotation speed of the compressor 2 (specifically, a sensor that detects the rotation speed of the engine 13). ) Or a sensor 52 (for example, a vehicle interior air temperature sensor, an outside air temperature sensor, a solar radiation amount sensor, etc.) that detects information necessary for air conditioning control. In addition to the above, a temperature setting device 53 for the passenger in the passenger compartment to set the desired temperature is connected.

Inside the ECU 20, there is a C (not shown).
A well-known microcomputer including a PU, a ROM, a RAM and the like is provided, and each of the sensors 10, 11, 51 and 5 described above is provided.
The signal from 2 is configured to be A / D converted by an input circuit (not shown) in the ECU 20, and then input to the microcomputer. The ECU 20
The power is supplied from a battery (not shown) when an ignition switch (not shown) of the engine 13 is turned on and an automatic air conditioner switch is turned on.

Next, the control process performed by the microcomputer of this embodiment will be described with reference to FIGS.
First, when the ignition switch is turned on, the ECU 20
When power is supplied to, the routine of FIG. 4 is started.
Then, in step 110, the sensors 10, 11,
A signal obtained by A / D converting each value of 51 and 52 is read, and a signal from the temperature setter 53 is read.

Then, in the next step 120, a target outlet temperature (hereinafter referred to as TAO) of the air blown into the vehicle compartment is calculated based on the signal read in the above step 110. Then, in the next step 130, the above step 1
The blower voltage corresponding to TAO calculated in 20 is stored in the ROM
Search and decide from. In step 140, the other air conditioning target values (excluding the air conditioning target value of the compressor 2) corresponding to the TAO calculated in step 130 are stored in the ROM.
Search and decide from.

Next, at step 150, the above step 1
The blower voltage determined in 30 is output to the blower driving means 9a, and in the next step 160, the air conditioning target value determined in step 140 is output to other air conditioning means (excluding the electromagnetic clutch 12). Then, the process returns to step 110 again. The microcomputer also executes the routine of FIG. 5 in addition to the routine of FIG. It should be noted that FIG. 5 is a flowchart showing a process relating to control of the compressor 2 among the processes performed by the microcomputer.

Specifically, when the ignition switch is turned on and power is supplied to the ECU 20, the routine of FIG. 5 is started. Then, in step 210, signals (Tef, T) obtained by A / D converting the respective values of the temperature sensor 10 before the evaporator, the temperature sensor 11 after the evaporator, and the rotation speed sensor 51.
er, Nc) and read step 130 in FIG.
Also read the blower voltage determined in.

Then, in the next step 220, the estimated operating rate φa is calculated based on the equation 2, and in the next step 230, it is judged whether or not the φa calculated in the step 220 is smaller than a predetermined value φ1. To do. Note that the predetermined value φ1 referred to here is the same as that of the compressor 2 shown in FIG.
It is a value obtained by preparing the experimental data shown in (1) in advance, obtaining the cooling capacity ratio Q1 from this experimental data, and correcting this Q1 to a percentage.

Then, if NO at step 230, that is, if φa ≧ φ1, at step 240, the compressor 2
The electromagnetic clutch 12 is controlled so as to be in the operating state.
That is, in this case, the capacity control is performed according to the cooling load. On the other hand, if YES is determined, step 25
At 0 to 330, on / off control of the compressor is performed based on the detection value (Ter) of the post-evaporator temperature sensor 11 so that the hysteresis characteristic shown in FIG. 6 is obtained.

Specifically, first, at step 250, it is judged if the flag BMC is set, and if it is judged that the flag BMC is set, then at step 260,
It is determined whether the detected value (Ter) is lower than the first predetermined temperature TeL. If it is determined to be low, the electromagnetic clutch 12 is controlled to stop the compressor 2, the flag BMC is reset in the next step 280, and then the process returns to step 210. On the contrary, if it is determined that the temperature is equal to or higher than the first predetermined temperature TeL, the flag BMC is set in step 290, and the process returns to step 210.

On the other hand, when it is determined in step 250 that the flag BMC is reset, in step 300, the detected value (Ter) is higher than the second predetermined temperature TeH which is higher than the first predetermined temperature TeL. Determine whether it is high or not.
If it is determined to be high, the electromagnetic clutch 12 is controlled to operate the compressor 2, the flag BMC is set in the next step 320, and the process returns to step 210. On the contrary, if it is determined that the temperature is not higher than the second predetermined temperature TeH, the flag BMC is set in step 330, and then the process returns to step 210.

As described above, in this embodiment, the blower voltage, the temperature sensor 10 before the evaporator, and the temperature sensor 1 after the evaporator 1
1, the estimated operating rate φa of the compressor 2 is obtained based on each determined value and the detected value of the compressor rotational speed, and the on / off control is performed when this φa is equal to or less than the predetermined value φ1, and the capacity control is performed when φa is equal to or more than φ1. Therefore, as can be seen from FIG. 8, the compressor 2 can be controlled so that the power ratio L / L0 of the compressor 2 becomes the smallest. Therefore, it is extremely effective in saving fuel consumption of the engine 13.

(Modification) As shown in FIG. 7, the cooling capacity ratio Q / Q0 and the compressor power ratio L / L when capacity control is performed.
The relationship with 0 depends on the compressor speed at that time. Therefore, for example, somewhere before step 230, there is provided a step (predetermined operation rate determining means of the invention according to claim 5) for determining the predetermined value φ1 based on the compressor rotation speed, and φ1 determined in this step is set. Step 2 based on
The determination of 30 may be performed. In this case, as can be seen from FIG. 7, the higher the compressor rotational speed, the larger the value of φ1 should be determined.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing the internal structure of the compressor 2 of the above embodiment.

FIG. 3 is a block diagram showing a configuration of a control system of the above embodiment.

FIG. 4 is a flowchart showing a control process performed by the microcomputer of the above embodiment.

FIG. 5 is a flowchart showing a control process performed by the microcomputer.

FIG. 6 is a characteristic diagram showing the relationship between the air temperature after evaporator and the target compressor state in the above embodiment.

FIG. 7 shows a compressor capacity control and an on-off control,
It is experimental data showing the relationship between the cooling capacity ratio and the compressor power ratio.

FIG. 8 shows a compressor capacity control and an on-off control,
It is experimental data showing the relationship between the cooling capacity ratio and the compressor power ratio.

FIG. 9 is experimental data showing the relationship between the actual compressor operating rate φ and the cooling capacity ratio.

FIG. 10 is experimental data showing the relationship between the estimated operating rate φa and the actual operating rate φ.

11A is a characteristic diagram showing the relationship between the air temperature after the evaporator and the target compressor state when the circled data in FIG. 10 is taken, and FIG. 11B is the triangle in FIG. It is a characteristic view which shows the relationship between the air temperature after an evaporator and the target compressor state when the data of a mark are taken.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Refrigeration cycle, 2 ... Compressor, 3 ... Condenser, 5 ... Expansion valve (pressure reducing means), 6 ... Evaporator, 8 ... Air conditioning duct (air passage), 9 ... Blower, 11 ... Evaporator temperature sensor (Cooling degree detecting means), 12 ... electromagnetic clutch (switching means),
51 ... Revolution sensor (revolution detection means)

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Mamoru Maeyama 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (56) References JP-A-64-90815 (JP, A) JP-A-58-96952 (JP, A) JP 59-212784 (JP, A) JP 2-237815 (JP, A) JP 59-74384 (JP, A) JP 3-25022 (JP, A) Kaihei 2-60818 (JP, A) Actual development Sho 59-120618 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B60H 1/32 623 B60H 1/32 622 B60H 1 / 32 624 F25B 1/00 341 F25B 1/00 361

Claims (6)

(57) [Claims] 1. A compressor for sucking, compressing and discharging a refrigerant, a condenser for condensing the refrigerant discharged by the compressor, a decompression means for decompressing the refrigerant from the condenser, and an evaporation of the refrigerant from the decompression means. A refrigerating cycle each including an evaporator for generating the air flow, an air blower for generating an air flow, an air passage in which the air generated by the air blower is introduced, and the evaporator is provided inside the evaporator, In an air conditioner having a cooling degree detecting means for detecting a degree of cooling the air in the air passage, the compressor is configured as an internal variable capacity compressor whose capacity changes according to a cooling load, Switching means for switching between operation and stop of the compressor is connected to the compressor, and estimated operating rate calculating means for calculating the estimated operating rate of the compressor, and the estimated operating rate. An estimated operating rate determining means for determining whether the estimated operating rate calculated by the calculating means is higher or lower than a predetermined operating rate; and the estimated operating rate determining means determines that the estimated operating rate is higher than the predetermined operating rate. When it is determined that the estimated operating rate is smaller than the predetermined operating rate by the first compressor control section that controls the switching section to operate the compressor, and the estimated operating rate determination section. A second compressor control means for controlling the switching means so as to operate or stop the compressor in accordance with the cooling degree detected by the cooling degree detecting means when determined. Air conditioning system to. 2. An air side load detecting means for detecting a heat load of air passing through the evaporator among the air in the air passage, and a refrigerant side capacity for detecting a cooling capacity of a refrigerant flowing in the evaporator. And a detection unit, wherein the estimated operating rate calculation unit is configured to calculate the estimated operating rate as a ratio of the load detected by the air side load detecting unit to the capacity detected by the refrigerant side capacity detecting unit. The air conditioner according to claim 1, wherein the air conditioner is provided. 3. The air-side load detection means determines the heat load of the air passing through the evaporator based on the product of the air volume passing through the evaporator and the temperature difference between the air before and after the evaporator. The air conditioner according to claim 2, wherein the air conditioner is configured to detect. 4. The refrigerant side capacity detecting means is configured to detect the cooling capacity of the refrigerant flowing in the evaporator based on the rotation speed of the compressor. The air conditioner described in 3. 5. A rotation speed detection means for detecting the rotation speed of the compressor, and a predetermined operation for determining the predetermined operation rate as a larger value as the compressor rotation speed detected by the rotation speed detection means becomes higher. Rate estimation means, the estimated operating rate determination means, whether the estimated operating rate calculated by the estimated operating rate calculation means is larger or smaller than the predetermined operating rate determined by the predetermined operating rate determination means. The air conditioner according to claim 1, wherein the air conditioner is configured to make a determination. 6. The second compressor control means controls the switching means to stop the compressor when the cooling degree detected by the cooling degree detecting means is larger than a predetermined cooling degree. 6. When the detected cooling degree is smaller than the predetermined cooling degree, the switching means is controlled so as to operate the compressor, and the switching means is controlled. Air conditioner.