JPH07285325A - Operation control device for refrigerating cycle - Google Patents

Abstract

PURPOSE:To effectively reduce a shock when the operation of a compressor is started with an inexpensive structure. CONSTITUTION:This operation control device for a refrigerating cycle is provided with an opening/closing device opening a refrigerant passage while gradually increasing the flow quantity and closing the refrigerant passage while gradually decreasing the flow quantity via the on or off of a solenoid valve 12 near to the intake port of a compressor and a control device 13 controlling a VSV 17 and a magnet clutch 8 connecting or disconnecting the solenoid valve 18, the compressor, and an engine with output signals A, B based on the start and stop signals from an air conditioner switch 15. When the air conditioner switch 15 is turned on, the output signal B is turned on, the output signal A is turned on after a prescribed time delay. When the air conditioner switch 15 is turned off, the output signal A is turned off, then the output signal B is turned off after a prescribed time delay.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigeration cycle equipped with a compressor for sucking in and compressing a gas refrigerant that has been heat-exchanged with the outside air by an evaporator through a refrigerant flow path. The present invention relates to a refrigeration cycle operation control device that operates and stops.

[0002]

2. Description of the Related Art A refrigeration cycle incorporated in an air conditioner system of a vehicle, for example, comprises a compressor, a condenser, a receiver, an expansion valve, and an evaporator, which are sequentially connected in a closed loop via pipes. The compressor is configured so that the rotational force of the engine is transmitted through a magnet clutch, and the operation control circuit is operated by the operation control circuit to connect and disconnect the magnet clutch based on start and stop signals of the air conditioner. It has become so.

[0003]

By the way, in recent years,
There is a demand for further improvement in ride comfort in vehicles,
It is desired to reduce shocks that occur when the compressor of the air conditioner system is started and stopped. Therefore, it is considered that a compressor having a variable capacity is adopted and a small capacity is started at the start of operation to reduce a shock when the compressor is turned on (for example, Japanese Patent Laid-Open No. 2-264179, Shokai 60-).
39792, JP-A-3-202695).

However, with such a variable capacity compressor, although a certain shock reduction can be achieved when the compressor is turned on, the shock reduction effect is not yet sufficient, and the function and effect are divided. There was a problem that the cost became high. still,
With this variable capacity compressor, since the compressor is not always operated at a small capacity when the compressor is off, there is a problem that it is not so effective in reducing the shock when the compressor is off.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a refrigerating cycle which can effectively reduce a shock at the start of operation of a compressor and can be relatively inexpensive. To provide an operation control device.

[0006]

A refrigeration cycle operation control apparatus according to claim 1 of the present invention is provided in a refrigerant passage between an evaporator and a compressor so as to open and close the refrigerant passage, and an opening operation is performed. Occasionally, an opening / closing device configured to open the refrigerant passage while gradually increasing the flow rate of the refrigerant, and based on a start signal, start operation of the compressor in a state where the refrigerant passage is closed, and then the opening / closing device. And a control means for controlling the opening / closing device and the compressor so as to perform the opening operation. In this case, the compressor may be connected to the drive source via the clutch, and the control means may be configured to control the operation of the compressor by engaging and disengaging the clutch (the invention of claim 2).

The opening / closing device is constructed so as to close the refrigerant passage while gradually reducing the flow rate of the refrigerant even during the closing operation, and the control means is arranged to close the opening / closing device based on the stop signal. It is more effective if the operation of the compressor is stopped after the operation is performed (the invention of claim 3). Further, it is preferable that the opening / closing device is provided near the suction port of the compressor in the refrigerant flow path (the invention of claim 4).

[0008]

According to the refrigeration cycle operation control device of the first aspect of the present invention, the operation of the compressor is started in a no-load state in which the refrigerant flow path is blocked by the opening / closing device and the refrigerant is not supplied to the compressor. Therefore, the shock at the start of compressor operation is only due to inertia. Then, after the operation of the compressor is started, the refrigerant flow path is opened and the refrigerant is supplied to the compressor.At this time, the switchgear is to open the refrigerant flow path while gradually increasing the flow rate of the refrigerant. Therefore, the load on the compressor gradually increases from the no-load state, and no shock occurs during this period.

In this case, if the operation of the compressor is controlled by connecting and disconnecting the clutch that connects the compressor to the drive source (the invention of claim 2), it is effective to generate a shock when the clutch is connected and disconnected. Can be prevented.

The opening / closing device is configured to close the refrigerant passage while gradually reducing the flow rate of the refrigerant even during the closing operation, and the control means closes the opening / closing device based on the stop signal. If the operation of the compressor is stopped after the operation is performed (the invention of claim 3), when the operation of the compressor is stopped, first, the flow rate of the refrigerant gradually decreases and the load on the compressor gradually decreases. The operation of the compressor is stopped after a no-load condition. Therefore, it is possible to reduce the occurrence of shock when the compressor is stopped.

Further, when the distance from the opening / closing device to the compressor becomes long, the volume of the refrigerant flow passage between them becomes relatively large, and therefore a slight shock occurs due to the compression of that volume by the compressor. If it is arranged near the suction port of the compressor in the refrigerant flow path (the invention of claim 4), the volume of the refrigerant flow path from the switchgear to the compressor becomes smaller, and the shock is more effectively generated. Can be reduced to

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an automobile air conditioner system will be described below with reference to the drawings. First, FIG. 4 shows a basic configuration of a refrigeration cycle 1 incorporated in an air conditioning system of an automobile.

The refrigeration cycle 1 includes a compressor (compressor) 2 that sucks and compresses a gas refrigerant, and a condenser (condenser) 3 that condenses the high-temperature and high-pressure refrigerant discharged from the compressor 2 into a liquid refrigerant. , This capacitor 3
As a receiver 4 for performing gas-liquid separation of the refrigerant flowing in from and for temporarily storing the liquid refrigerant, and a throttle device for rapidly expanding the liquid refrigerant sent from the receiver 4 to form a low-temperature, low-pressure mist state Expansion valve (expansion valve)
5. Evaporator that heat-exchanges the atomized refrigerant from the expansion valve 5 with the outside air
6 are sequentially connected in a closed loop by a pipe 7 and a required amount of refrigerant is sealed therein. In FIG. 4, the flow direction of the refrigerant is indicated by black arrows.

At this time, in this embodiment, the compressor 2 is connected to an engine (not shown) as a drive source via a magnet clutch 8 also shown in FIG. 1, and the clutch 8 is disengaged. It is designed to be started and stopped by. Further, heat exchange of the condenser 3 is promoted by blowing air from the engine cooling fan 9, and the cool air generated by the evaporator 6 is supplied into the vehicle compartment by the blower 10. ing. In the present embodiment, the portion of the pipe 7 between the evaporator 6 and the compressor 2 is
Hereinafter, it will be referred to as the coolant channel 7a.

An opening / closing device 11 for opening / closing the refrigerant passage 7a is provided near the suction port of the compressor 2 in the refrigerant passage 7a. Although not shown in detail, the opening / closing device 11 includes an opening / closing valve that operates by pilot pressure to open / close the refrigerant flow path 7a and an electromagnetic valve 12 (see FIG. 1) that connects / disconnects the pilot pressure. An orifice or choke for slowing the response speed is provided in the pilot pressure introducing passage.

Thus, the switchgear 11 opens the refrigerant flow path 7a by turning on (energizing) the solenoid valve 12,
When the solenoid valve 12 is turned off (disconnected), the refrigerant flow path 7
It is designed to block a. At this time, in the opening operation, it takes several seconds to 2 to 30 seconds from when the solenoid valve 12 is turned on until the refrigerant flow path 7a is fully opened, and during that time, the flow rate of the refrigerant gradually increases. Further, during the closing operation, it takes several seconds to 2 to 30 seconds after the solenoid valve 12 is turned off until the refrigerant flow path 7a is fully closed, during which the refrigerant flow amount is gradually reduced.

The compressor 2 and the opening / closing device 11 described above are controlled by a control device 13 as a control means. FIG. 1 shows a simplified electrical configuration of an operation control device for the refrigeration cycle 1 including the control device 13. Here, the control device 13 is connected to a power source 14 such as a battery or a generator. The start (ON) and stop (OFF) signals from the air conditioner switch 15 are input. Also, air conditioner switch 1
A pressure switch 16 that is turned off when the refrigerant pressure is abnormal is provided between the control device 5 and the control device 13.

Further, the solenoid valve 12 and the magnet clutch 8 are connected to the control device 13, and a vacuum switching valve (VSV) 17 for engine idle-up is also connected. Among them, the solenoid valve 12 is controlled by the output signal A, and the magnet clutch 8 and the VSV 17 are controlled by the output signal B.

FIG. 2 is a block diagram showing a circuit configuration of the control device 13. The start and stop signals from the air conditioner switch 15 are directly input to one input terminal of the AND gate 18 and the not gate 19. , One-shot multi-vibrator 20, and a timer 21 for providing a time difference, which is then inverted and input to the other input terminal of the AND gate 18. And
An output signal A is output from the AND gate 18.

Further, the start / stop signal from the air conditioner switch 15 is directly input to one input terminal of the OR gate 22, and the one-shot multivibrator 23 and the timer 24 for providing a time difference are used to operate the OR gate 22. It is designed to be input to the other input terminal. An output signal B is output from the OR gate 22.

Thus, as shown in FIG. 3, when the air conditioner switch 15 is turned on (time T1), the output signal B is turned on (high level), and Δt1 has elapsed from time T1 (time t1). The output signal A is turned on (high level) at T2). The delay time Δt1 at this time is set to the timer 21 such that the slip time until the magnet clutch 8 is completely engaged is about 0.1 seconds, while it is slightly longer than that (1 second or less at most). It is set.

On the other hand, when the air conditioner switch 15 is turned off (time T3), the output signal A is turned off (low level), and Δt2 has elapsed from time T3 (time T3).
In 4), the output signal B is turned off (low level). The delay time Δt2 at this time is set in the timer 24 so as to be slightly longer than the response speed of the solenoid valve 12 (opening / closing device 11) described above.

Next, the operation of the above configuration will be described. When the air conditioner switch 15 is in the off state, the magnet clutch 8 is in the power-off state, the compressor 2 is disconnected from the drive source, and the solenoid valve 1 is in the stopped state.
2 is also in a power-off state, and the switching device 11 causes the refrigerant flow path 7a.
Is blocked.

When the air conditioner switch 15 is turned on from this state (time T1), as shown in FIG. 3, first, the output signal B from the control device 13 is turned on, the magnet clutch 8 is connected, and the compressor 2 of the compressor 2 is connected. When the operation is started, the VSV 17 is driven. At this time, since the opening / closing device 11 (electromagnetic valve 12) has not been opened yet, the operation of the compressor 2 is started in the unloaded state in which the refrigerant flow path 7a is closed and the refrigerant is not supplied. Therefore, the shock at the start of operation of the compressor 2 (when the magnet clutch 8 is connected) is only due to inertia,
The shock that occurs is the smallest possible.

Then, at time T2 which is delayed by time Δt1 from time T1, the output signal A from the control device 13 is turned on, the solenoid valve 12 is energized, and the opening / closing device 11 is opened. As a result, the refrigerant flow path 7a is opened and the refrigerant is supplied to the compressor 2. At this time, the switchgear 11 opens the refrigerant flow path 7a while gradually increasing the flow rate of the refrigerant. Therefore, the load on the compressor 2 gradually increases from the no-load state, and no shock occurs during this period.

On the other hand, refrigeration cycle 1 (compressor 2)
When the air conditioner switch 15 is turned off from the operating state (time T3), first, the output signal A from the control device 13 is turned off, the electromagnetic valve 12 is turned off, and the opening / closing device 11 is closed. As a result, during the time Δt2, the flow rate of the refrigerant in the refrigerant flow path 7a gradually decreases, and the load on the compressor 2 gradually decreases. Finally, the refrigerant flow path 7a becomes fully closed and the compressor 2 Becomes unloaded.

Then, after the compressor 2 has become unloaded, the output signal B from the controller 13 is turned off at time T4, the magnet clutch 8 is disengaged, the operation of the compressor 2 is stopped, and the VSV 17 Is also stopped. Therefore, the shock when the operation of the compressor 2 is stopped (when the magnet clutch 8 is disengaged) is extremely small.

By the way, when the distance from the opening / closing device 11 to the compressor 2 becomes long, the volume of the refrigerant flow path 7a between them becomes relatively large, so that the compression of the volume by the compressor 2 causes a slight shock. However, in this embodiment, since the opening / closing device 11 is arranged in the refrigerant flow path 7a in the vicinity of the suction port of the compressor 2, the volume of the refrigerant flow path 7a from the opening / closing device 11 to the compressor 2 is small. As a result, the shock can be reduced and the occurrence of shock can be reduced more effectively.

In general, at the time of starting the engine, there is a circumstance in which liquid compression is likely to occur due to the accumulation of liquid refrigerant in the compressor and in the piping, but in this embodiment, the opening / closing device 11 is performed when the engine is stopped. Is closed, and when the compressor 2 starts operating, the compressor 2
Almost no liquid refrigerant is stored inside, and the pipe 7
Since the liquid refrigerant accumulated in the (refrigerant flow path 7a) is also gradually sucked in small amounts while being throttled by the opening / closing device 11, an excessive pressure does not act and a problem such as damage to the compressor 2 due to liquid compression occurs. It is also possible to obtain an advantage that the occurrence can be prevented.

Thus, according to this embodiment, the switchgear 1
1 and the control device 13, the operation of the compressor 2 is started in the unloaded state in which the refrigerant flow path 7a is closed and the refrigerant is not supplied, and then the flow rate of the refrigerant is gradually increased. It is possible to effectively reduce the shock. In this case, the shock that can be generated is the smallest that can be considered compared to the conventional one that adopted a variable capacity compressor and started small capacity at the start of operation, and the effect of shock reduction is remarkable. Becomes

Moreover, in the present embodiment, it is not necessary to employ a variable capacity compressor, shock can be reduced with a relatively simple structure, and the cost can be reduced. Also, as for the configuration of the opening / closing device 11, if the refrigerant passage 7a is directly opened / closed by an electromagnetic valve, it becomes large in size due to the pipe resistance, which is effective, but in the present embodiment, the opening / closing device 11 serves as an opening / closing valve. Solenoid valve 1 for pilot pressure
Since the configuration of intermittent connection by 2 is adopted, the cost can be reduced.

Further, in the present embodiment, the circuit configuration of the control device 13 allows the operation of the compressor 2 to be stopped,
Since the compressor 2 is stopped after the no-load state, it is possible to effectively reduce the shock when the compressor 2 is stopped. Further, by providing the opening / closing device 11 in the vicinity of the suction port of the compressor 2, it is possible to obtain an advantage that it is possible to more effectively reduce the occurrence of shock.

As a result, particularly when applied to an air conditioner system for a vehicle, it is possible to sufficiently meet the demand for reducing the shock generated at the start and stop of the operation of the compressor 2 (when the magnet clutch 8 is disengaged). Therefore, the riding comfort of the vehicle can be further improved.

The present invention is not limited to the above-mentioned embodiments, and for example, as the structure of the opening / closing device, various structures can be used as long as the opening / closing device is configured to open / close while gradually increasing or decreasing the flow rate of the refrigerant. The structure can be adopted, and the position where the opening / closing device is provided may be any position in the refrigerant flow path between the evaporator and the compressor. Further, the configuration of the control means may be such that it is possible to shift the on / off timing as shown in FIG. 3, and the control means can be appropriately modified and implemented without departing from the spirit of the invention. .

[0035]

As is apparent from the above description, according to the present invention, the following excellent effects can be obtained. That is, according to the operation control device of the refrigeration cycle of claim 1,
An opening and closing device configured to open the refrigerant flow path while gradually increasing the flow rate of the refrigerant during the opening operation, which is provided to open and close the refrigerant flow path in the refrigerant flow path between the evaporator and the compressor, A control means for controlling the opening / closing device and the compressor so as to start the operation of the compressor in a state where the refrigerant flow path is closed based on the start signal and then perform the opening operation of the opening / closing device is provided. The shock can be effectively reduced at the start of operation, and the cost can be relatively reduced.

In this case, if the operation of the compressor is controlled by connecting and disconnecting the clutch that connects the compressor to the drive source (the operation control device of the refrigeration cycle according to claim 2), the clutch can be connected and disconnected. It is possible to effectively prevent the occurrence of shock.

The opening / closing device is configured to close the refrigerant passage while gradually reducing the flow rate of the refrigerant even during the closing operation, and the control means closes the opening / closing device based on the stop signal. If the operation of the compressor is stopped after the operation is performed (the operation control device for the refrigeration cycle according to claim 3), it is possible to reduce the occurrence of shock when the operation of the compressor is stopped.

Further, when the distance from the switchgear to the compressor becomes long, the volume of the refrigerant flow passage between them becomes relatively large, so that compression of that volume by the compressor causes a slight shock. If it is provided near the suction port of the compressor in the refrigerant flow path (the operation control device of the refrigeration cycle according to claim 4), the volume of the refrigerant flow path from the switchgear to the compressor becomes small, and the shock Occurrence can be reduced more effectively.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention and showing a simplified electrical configuration.

FIG. 2 is a block diagram showing a configuration of a control device.

FIG. 3 is a diagram showing a relationship between a signal of an air conditioner switch and output signals A and B of a control device.

FIG. 4 is a diagram showing a basic configuration of a refrigeration cycle.

[Explanation of symbols]

In the drawing, 1 is a refrigeration cycle, 2 is a compressor, 6 is an evaporator, 7a is a refrigerant flow path, 8 is a magnetic clutch, 11 is an opening / closing device, 12 is a solenoid valve, 13 is a control device (control means), and 15 is an air conditioner switch. Indicates.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display area F25B 1/053 N

Claims (4)

[Claims] 1. A refrigeration cycle including a compressor that sucks and compresses a gas refrigerant that has been heat-exchanged with the outside air by an evaporator through a refrigerant flow path, and operates and stops the compressor based on a start / stop signal. Wherein the opening and closing device is provided in the refrigerant passage so as to open and close the refrigerant passage, and is configured to open the refrigerant passage while gradually increasing the flow rate of the refrigerant during the opening operation; A control means for controlling the opening / closing device and the compressor so as to start the operation of the compressor in a state where the refrigerant flow path is closed based on the signal, and then perform the opening operation of the opening / closing device. A characteristic operation control device for a refrigeration cycle. 2. The compressor is connected to a drive source via a clutch, and the control means is configured to control the operation of the compressor by engaging and disengaging the clutch. Item 1. A refrigeration cycle operation controller according to Item 1. 3. The opening / closing device is configured to close the refrigerant flow passage while gradually reducing the flow rate of the refrigerant even during the closing operation, and the control means controls the opening / closing device based on the stop signal. The operation control device for a refrigeration cycle according to claim 1 or 2, wherein the operation of the compressor is stopped after the closing operation is performed. 4. The operation control device for a refrigerating cycle according to claim 1, wherein the opening / closing device is provided near a suction port of the compressor in the refrigerant flow path. .