JPS62125262A - Air conditioning compressor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an air conditioning compressor that compresses fluid circulating in a refrigeration cycle.

(Prior Art) As such an air conditioning compressor, there is a conventional compressor as shown in FIG. 6, for example. This air conditioning compressor 1 constitutes a refrigeration cycle together with an evaporator and a condenser, and sucks refrigerant gas (circulating through the refrigeration cycle) into pump chambers (compression chambers) 4 and 5 from suction ports 2 and 3. The refrigerant gas sucked into the suction port 3 and the pump chamber 4 is compressed by a plurality of vanes 8 supported so as to project freely through a plurality of slits 7 of a rotor 6 rotating in the direction of the arrow.
From 0, the discharge valves 11 and 12 are pushed open to be discharged and sent to the downstream side of the refrigeration cycle.

(Problems to be Solved by the Invention) However, in such conventional air conditioning compressors, the discharge capacity is constant (even if one of the suction ports 2 and 3 is closed to reduce the capacity to 1/2, the discharge capacity remains 1/2). 2), and the discharge capacity cannot be changed continuously, so the lower first set temperature (evaporator antifreeze temperature) is set at 1+.
A higher second set temperature t2 having a predetermined temperature difference is set, and as shown in FIG. 7(a), the temperature of the evaporator or the air blown out from it decreases to the first set temperature t1.
When the temperature reaches 1, the electromagnetic clutch is turned OFF to stop the operation of the air conditioning compressor 1, as shown in Fig. 7 1b).
When the temperature rose again and reached the second set temperature t2, the electromagnetic clutch was turned on to operate the air conditioning compressor again. If only one set temperature is set at t+, the electromagnetic clutch of the air conditioning compressor 1 will repeatedly turn on and off violently in a very short period of time, which is what is called hunting (chattering). A second set temperature t2 having a temperature difference is set. For this reason, even if hunting can be prevented,
Air conditioning compressor 1 at predetermined intervals with a longer cycle than hunting
When the electromagnetic clutch repeatedly turns ON and OFF, noise or impact is generated each time, causing an unpleasant feeling to the occupants.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention constitutes a refrigeration cycle together with an evaporator, and compresses the fluid that circulates through the refrigeration cycle, sucked in through the suction port, in a compression chamber and discharged. In an air-conditioning compressor, a temperature detection means for detecting the temperature of the evaporator or the temperature of the air blown out from the evaporator, and a temperature detection means for detecting the temperature of the air blown out from the evaporator; A suction hole closing control means for controlling the suction hole to close at a certain rate is provided.

(Function) According to such an air conditioning compressor, a predetermined rate of closing the inlet per unit time is determined based on the temperature of the evaporator detected by the temperature detection means or the temperature of the air blown out from the evaporator. By changing the temperature, the discharge capacity of the air conditioning compressor can be continuously changed to maintain the temperature near the target value. Therefore, the electromagnetic clutch of the air conditioning compressor can be prevented from repeatedly turning ON and OFF in a complicated manner as in the past, and the noise or impact caused by the ON and OFF operations can be prevented from causing unpleasant confusion to the occupants. be able to.

(Example) Hereinafter, a first example of an air conditioning compressor according to the present invention will be described based on the drawings.

In FIG. 1, 20 is an air conditioning compressor, and 22 is a condenser (condenser) that cools and liquefies a refrigerant (fluid circulating in the refrigeration cycle) such as Freon gas, which has been compressed by the air conditioning compressor 20 to a high temperature and high pressure. ), 24 is this capacitor 22
This is an evaporator that evaporates the liquefied refrigerant sent from the surrounding air, extracts heat from the surrounding air, and converts it into a gas. The refrigerant gasified in the evaporator 24 is returned to the compressor 2
0, repeating this series of refrigerant cycles,
It continues to remove heat from the air inside the vehicle to lower the temperature. Also,
Reference numeral 26 denotes a temperature sensor (temperature detection means) installed on the cooling air outlet side of the evaporator 24 to detect the temperature of the air blown out from the evaporator 24. A temperature switch, a thermistor thermometer, or the like is used as the temperature sensor 26, and the temperature sensor 26 outputs a temperature signal to the control unit 28. The control unit 28 outputs control signals to the on-off valves 30 and 31 such as electromagnetic valves based on the temperature signal from the temperature sensor 26, and outputs control signals to the inlets 33 and 3 of the air conditioning compressor 20.
The on-off valves 30 and 31 are controlled to close the valves 4 at a predetermined rate per arbitrary unit time. The control unit 28 and the on-off valves 30.31 constitute a suction hole closing control means 35. In the figure, 36 is a liquid tank that separates the refrigerant liquefied by the condenser 22 into gas and liquid, 38 is an expansion valve, and 40 is an electric fan (
blower).

As shown in FIG. 2, the air conditioning compressor a20 includes a cam ring 42 having a substantially elliptical cam surface 42a, and within this cam ring 42, a rotor 44 having substantially the same diameter as the short diameter of the cam surface 42a is mounted on the cam surface 42a. It is rotatably housed around the center of the long diameter of. A plurality of slits 45 arranged approximately radially are formed in the rotor 44, and a plurality of vanes 46 are fitted into the slits 45 so as to be able to protrude freely. A back pressure passage 47 is formed at the bottom of the slit 45, and each back pressure passage 47 communicates with a communication hole 48 formed in the rotor 44. Lubricating oil is supplied. cam ring 42
In the space between the rotor 44 and the rotor 44, pump chambers 49 and 50 are defined by adjacent vanes 46. A refrigerant such as freon gas is sucked into the pump chambers (compression chambers) 49 and 50 from the respective suction ports 33 and 34, and the rotor 44
The centrifugal force accompanying the rotation of the lubricating oil in the back pressure passage 47 (
The vane '46 slides into contact with the cam surface 42a and rotates due to the vane back pressure. As a result, the refrigerant is compressed and discharged from the corresponding discharge ports 51 and 52 by pushing open the discharge valves 53 and 54, and the refrigerant is discharged from the condenser 2 on the downstream side of the refrigeration cycle.
Sent to 2.

Next, the effect will be explained. Electromagnetic clutch not shown is ON
As a result, the air conditioning compressor 20 rotates the rotor 44 and starts operating, and the refrigerant circulates through the refrigeration cycle to cool the air. In other words, the air conditioning compressor 2
The refrigerant compressed at 0 is cooled and liquefied by the condenser 22,
Next, as the air evaporates in the evaporator 24, heat is removed from the air in the vehicle interior to cool the interior of the vehicle. At this time, the temperature sensor 26 detects the temperature of the air blown out from the evaporator 24, and sends a temperature signal corresponding to that temperature to the control unit 24.
Output to 8. The control unit 28 controls the on-off valves 30 and 31 based on the temperature signal input from the temperature sensor 26.
A control signal is output to control the opening and closing of the gate. For example, as shown in FIG. 3(a), when the temperature of the air blown out from the evaporator 24 by the operation of the air conditioning compressor 20 begins to decrease and reaches the target value temperature t2, the control unit 28 closes the intake ports 33 and 34. A duty signal is output to the on-off valves 30 and 31 so that they close at a predetermined rate per unit time. As a result, the discharge capacity of the air conditioning compressor 20 gradually decreases as shown in FIG. The temperature value t2 is reached. In response to the temperature signal from the temperature sensor 26 that detects that the air temperature has reached t2 again, the control unit 28 sends a duty signal to the on-off valves 30 and 31 so that the discharge capacity of the air conditioning compressor 20 gradually increases again. Output. When the discharge capacity of the air conditioning compressor 20 increases, the air temperature drops again and reaches the target value t2 again. By repeating such a control cycle, the discharge capacity of the air conditioning compressor [20] can be continuously changed while the electromagnetic clutch is kept ON, and the temperature of the air blown out from the evaporator 24 can be adjusted to a predetermined target value t2. It can be kept nearby. For this reason,
The electromagnetic clutch of the air conditioning compressor is turned on repeatedly as before.
.

It is possible to avoid repeating OFF, and the ON, O
It is possible to effectively prevent the occupant from being uncomfortable and confused due to the noise or impact caused by the FF. In addition, the third
1 in Figure (a) is the antifreeze temperature of the evaporator 24, and the above control can also prevent the air temperature from dropping to this temperature t1.

FIG. 4 shows a second embodiment of the present invention.

In the first embodiment, the air temperature decreases to the target value t.
2, the control unit 28 controls the air conditioning compressor 20.
In contrast, in this second embodiment, when the air temperature reaches the target value t2, the control unit 28 As shown in FIG. 4(b), a duty signal is sent to the on-off valves 3o and 31 so that the discharge capacity of the air conditioning compressor 20 is first rapidly reduced by a predetermined amount p, and then the discharge capacity is further gradually reduced. It is designed to be output. When the air temperature rises again and reaches the target value t2, the on-off valves 3o and 3
1 to output a duty signal.

By repeating such a control cycle, the increase or decrease in air temperature can be corrected more quickly than in the first embodiment, and the air temperature can be brought closer to the target value t2 than in the first embodiment. can be held. Such a second embodiment is considered to be more desirable than the first embodiment when the air temperature before cooling is high, such as in midsummer.

FIG. 5 shows a third embodiment of the present invention.

In the first embodiment, the air temperature decreases to the target value t.
2, the control unit 28 controls the air conditioning compressor 20.
The valve 30.3 is uniformly opened and closed so that the discharge capacity of the valve gradually decreases.
1, and the control state did not change until the air temperature rose again and reached t2, so even if the control state in which the discharge capacity of the air conditioning compressor 20 gradually decreased was continued. If the air temperature did not start to rise, no measures were taken. Therefore, there is a risk that the air temperature may drop to the freezing prevention temperature t of the evaporator 24 and the evaporator 24 may freeze. On the other hand, in this third embodiment, the air temperature decreases and the target value t
2, the control unit 28 controls the air conditioning compressor 20.
A duty signal is output to the on-off valves 30 and 31 so that the discharge capacity of When the anti-freezing temperature t1 is reached, the control unit 28 causes the discharge capacity of the air conditioning compressor 20 to rapidly decrease by a predetermined amount S, as shown by the solid line in FIG. The duty signal is output to the on-off valves 30 and 31 so that the discharge capacity of the air conditioning compressor 20 gradually decreases until the air temperature reaches the target value t2. After exceeding the limit, the discharge capacity is rapidly increased by a predetermined amount r to return to the same control state as in the first embodiment, and then duty is applied to the on-off valves 3o and 31 so as to gradually increase the discharge capacity. According to the third embodiment, when the air temperature before cooling is low, such as in early spring, the air temperature does not start to rise even if the discharge capacity is slightly reduced. In some cases, this is considered to be more preferable than the first embodiment.The broken line in FIG. 5 shows the first embodiment for ease of comparison with the third embodiment.

In the above embodiment, a case has been described in which the temperature sensor 26 detects the temperature of the air blown out from the evaporator 24, but the same effect can be obtained even if the temperature sensor 26 detects the temperature of the evaporator 24 itself. be able to.

(Effects of the Invention) As explained above, according to the present invention, the temperature of the evaporator or the air blown out from the evaporator is changed by changing the time ratio for closing the inlet of the compressor based on the temperature of the air blown out from the evaporator. is maintained near the target value, so the electromagnetic clutch of the air conditioning compressor is no longer repeatedly turned ON and OFF like in the past.
You can avoid repeating FF, and its 0NSOF
It is possible to effectively prevent the passenger from feeling uncomfortable due to the noise or impact caused by F. Further, according to the first embodiment, by maintaining the temperature near the target value, it is possible to prevent the temperature from dropping to the anti-freezing temperature. Further, according to the second embodiment, it is possible to correct a rise or fall in temperature more quickly than in the first embodiment, and it is better than the first embodiment, especially when the season is midsummer. Furthermore, according to the third embodiment, when the air temperature before cooling is low, such as in early spring,
This embodiment is superior to the first embodiment when the air temperature does not rise even if the discharge capacity is slightly reduced.

[Brief explanation of drawings]

1 to 3 are diagrams showing a first embodiment of an air conditioning compressor according to the present invention, FIG. 1 is an overall view of a refrigeration cycle including the air conditioning compressor, and FIG. 2 is a diagram showing the air conditioning compressor. A cross-sectional view of
Figure 3 ta) is a diagram of the relationship with time showing the temperature change due to the air conditioning compressor, Figure 3 ta) is the diagram of the relationship with time showing the change in the discharge capacity of the air conditioning compressor, and Figure 4 is a diagram of the relationship with time showing the change in the discharge capacity of the air conditioning compressor. FIG. 4(b) is a diagram showing a second embodiment of the present invention, and FIG.
1 is a diagram showing the change in discharge capacity of the air conditioning compressor as a function of time, and FIG. 5 is a diagram showing a third embodiment of the present invention.
Fig. 5(a) is a diagram showing the relationship between temperature and time due to the air conditioning compressor; , FIG. 7 is a diagram showing a conventional air conditioning compressor, FIG. 6 is a sectional view of the air conditioning compressor, and FIG. The relationship diagram, FIG. 7(b) is a time chart showing ON/OFF changes of the electromagnetic clutch of the air conditioning compressor. 20...Air conditioning compressor, 22...Capacitor , 24... Evaporator (evaporator), 26...
...Temperature sensor (temperature detection means), 28...
Regulation? IIl-L Knit, 30.31... Opening/closing valve, 33.34... Suction port, 35... Suction port closing control means, 36...
・Liquid tank, 38... Expansion valve, 40... Electric fan, 42... Cam ring, 42a... Cam surface, 44... Rotor, 45...Slit, 46...Vane, 47...Back pressure passage, 48...Communication hole, 49.50... Pump chamber (compression chamber), 51.5
2...Discharge port, 53.54...Discharge valve. Fig. 1 20: Misfortune of the branch newspaper. 24; Evaporator (certain 1. [Kane) 26;
Sakiiri Wa 35: Kiriyo 2\at,, Fl Kamiru' Town Imahara 2nd Figure 49.50i Bona Branch (Mr. #i) No. 312J Winter t. Figure 4 Love θ□ Figure 5

Claims (1)

[Claims] In an air conditioning compressor that constitutes a refrigeration cycle together with an evaporator and compresses fluid circulating in the refrigeration cycle that is sucked in from an inlet in a compression chamber and then discharges it, the temperature of the evaporator or the temperature of the air blown out from the evaporator and a suction hole closing control means for controlling the suction port to be closed at a predetermined rate per arbitrary unit time based on the temperature detected by the temperature sensing means, An air conditioning compressor, characterized in that the temperature is maintained near a target value by changing a predetermined rate at which the suction port is closed.