JP6447153B2 - Air conditioner, vehicle, air conditioner failure detection method and program - Google Patents

Description

  The present invention relates to an air conditioner, a vehicle, an air conditioner failure detection method, and a program.

An engine-driven air conditioner that directly operates a compressor based on power generated by engine rotation is known. In such an engine-driven air conditioner, for example, an electromagnetic clutch is provided in a power transmission system (such as a belt) from the engine to the compressor, and the power transmission system between the engine and the compressor is connected or disconnected. Can be performed as desired.
In the engine-driven air conditioner, an air conditioner in which a plurality of compressors are connected to one engine has been proposed (see, for example, Patent Document 1).

JP 2009-030876 A

  In the engine-driven air conditioner as described above, when any abnormality (engine stall, abnormal engine speed fluctuation, abnormal pressure fluctuation, etc.) is confirmed in its operation, for example, a compressor failure is assumed. In this case, in order to easily determine whether or not a failure has occurred in the compressor, the engine is actually rotated by connecting an electromagnetic clutch and the operation of the compressor is attempted.

  However, depending on the compressor failure, the compressor may be unable to rotate (rotation locked state). If the compressor is in the rotation locked state and the electromagnetic clutch is connected to try to force the compressor to operate, slipping of the belt will occur, causing excessive load and damage to the power transmission system. There is a case.

  An object of the present invention has been made in view of the above-described problems, and is an air conditioner, a vehicle, and an air conditioner that can easily determine whether there is a failure in a compressor without applying an excessive load to a power transmission system. An object of the present invention is to provide a machine failure detection method and program.

  One aspect of the present invention is an engine, a compressor that operates based on power generated by rotation of the engine, a power transmission device that can connect and disconnect a power transmission system from the engine to the compressor, An air conditioner comprising: controlling the power transmission device to connect the transmission system for a predetermined time during rotation of the engine; and fluctuations in the rotational speed of the engine within the predetermined time It is an air conditioner provided with the failure determination part which determines the presence or absence of the failure in the said compressor based on.

  Further, according to one aspect of the present invention, in the above-described air conditioner, when the failure determination unit determines that there is no failure of the compressor based on the fluctuation in the rotation speed, the failure determination unit further includes the transmission system. Connection is performed to operate the compressor, and the presence or absence of a failure in the compressor is determined based on a change in pressure or discharge temperature corresponding to the operation of the compressor.

  Moreover, according to one aspect of the present invention, the above-described air conditioner includes a plurality of the compressors, and the failure determination unit determines whether or not there is a failure in one of the compressors, and then performs the other compression. Determine if there is a malfunction in the machine.

  Moreover, according to one aspect of the present invention, the above-described air conditioner further includes a pressure equalizing on / off valve disposed on a pipe connecting a discharge side and a suction side of the compressor, and the failure determination unit includes: After determining whether or not there is a failure with respect to one of the compressors, the pressure equalizing on / off valve is opened, and pressure equalization processing is performed on the pressure changed based on the operation of the compressor.

  Moreover, according to one aspect of the present invention, the above-described air conditioner selects a normal compressor from the plurality of compressors based on a determination result by the failure determination unit, and operates the selected compressor. Let

  One embodiment of the present invention is a vehicle including the above-described air conditioner.

  In one embodiment of the present invention, an engine, a compressor that operates based on power generated by the rotation of the engine, and a power transmission device that can connect and disconnect a power transmission system from the engine to the compressor A failure detection method for detecting the presence or absence of a failure in an air conditioner comprising: controlling the power transmission device to connect the transmission system for a predetermined time during rotation of the engine; An air conditioner failure detection method comprising a step of determining whether or not the compressor has failed based on fluctuations in the engine speed within the specified time.

  In one embodiment of the present invention, an engine, a compressor that operates based on power generated by the rotation of the engine, and a power transmission device that can connect and disconnect a power transmission system from the engine to the compressor A computer of an air conditioner comprising: controlling the power transmission device to connect the transmission system for a predetermined time during rotation of the engine, and rotating the engine speed within the predetermined time It is a program that functions as a failure determination means for determining whether or not there is a failure in the compressor based on the fluctuation of the compressor.

  According to the above-described air conditioner, vehicle, and air conditioner failure detection method and program, it is possible to easily determine whether there is a failure in the compressor without applying an excessive load to the power transmission system.

It is a figure which shows the function structure of the air conditioning machine which concerns on 1st Embodiment. It is a figure which shows typically the structure of the engine and compressor which concern on 1st Embodiment. It is a 1st figure which shows the processing flow of the failure determination part which concerns on 1st Embodiment. It is a 2nd figure which shows the processing flow of the failure determination part which concerns on 1st Embodiment. It is a 1st figure explaining the failure determination process of the failure determination part which concerns on 1st Embodiment. It is a 2nd figure explaining the failure determination process of the failure determination part which concerns on 1st Embodiment.

<First Embodiment>
Hereinafter, the air conditioner according to the first embodiment will be described with reference to FIGS.

(Functional configuration of air conditioner)
FIG. 1 is a diagram illustrating a functional configuration of the air conditioner according to the first embodiment.
As shown in FIG. 1, the air conditioner 1 includes an engine 10, two compressors 11 (first compressor 11A, second compressor 11B), and two electromagnetic clutches 12 (first electromagnetic clutch 12A, second compressor). The electromagnetic clutch 12B) and the operation control unit 13 are provided.
In addition, the air conditioner 1 includes a high pressure sensor P1, a discharge temperature sensor T1, a condenser C, and a suction side of the compressor 11 (see FIG. 1) arranged on the discharge side (high pressure side shown in FIG. 1) piping of the compressor 11. 1 and a low pressure sensor P2 and an evaporator E arranged on the pipe on the low pressure side shown in FIG.
Further, the air conditioner 1 includes a check valve V1 disposed upstream of the capacitor C, an expansion valve V2 disposed between the capacitor C and the evaporator E, a high-pressure side pipe, and a low-pressure side pipe. And a pressure equalizing on-off valve V3 provided on the relay pipe.

  The engine 10 is a power source that generates power by burning fuel. The engine 10 transmits power generated by the rotation to the two compressors 11 to operate the compressors 11.

The two compressors 11 suck the suction side refrigerant gas and discharge it to the discharge side by an operation (rotation) based on the power from the engine 10. As a result, the refrigerant in the suction side pipe is reduced in temperature and pressure, and the refrigerant in the discharge side pipe is increased in temperature and pressure. As a result, in the evaporator E arranged on the low pressure side and the capacitor C arranged on the high voltage side, heat is sucked and released (heat exchange), and the function as an air conditioner is exhibited.
The two compressors 11 operate based on the power of the engine 10 transmitted through a power transmission system having the electromagnetic clutch 12.

  The two electromagnetic clutches 12 are connected to a power transmission system from the engine 10 to the compressors 11 in accordance with a predetermined control signal (control signal D described later) that is input. It is one mode. Specifically, the first electromagnetic clutch 12A is provided in a power transmission system between the engine 10 and the first compressor 11A, and the second electromagnetic clutch 12B is provided between the engine 10 and the second compressor 11B. It is provided in the power transmission system. The first electromagnetic clutch 12A and the second electromagnetic clutch 12B can be independently controlled.

The operation control unit 13 is a processor that controls operation of the entire air conditioner 1. Specifically, during operation of the air conditioner 1, the operation control unit 13 is based on various detection results from the low pressure sensor P1, the high pressure sensor P2, the discharge temperature sensor T1, and the rotation speed detection sensor R1, and the engine 10, The two electromagnetic clutches 12 and the like are controlled. For example, the operation control unit 13 sets each of the first electromagnetic clutch 12A and the second electromagnetic clutch 12B to a connected state or a disconnected state according to the detection result, whereby the first compressor 11A and the second compressor 11B. The cooling capacity of the air conditioner 1 is adjusted by operating or stopping.
The operation control unit 13 has a function as the failure determination unit 130. The failure determination unit 130 detects an abnormality in the air conditioning operation of the air conditioner 1 and performs a process for specifying a cause (failure location) of the abnormal operation.

  The high-pressure sensor P1 is a sensor that is arranged in the discharge side (high pressure side) pipe of the compressor 11 and can detect the refrigerant pressure in the discharge side pipe. The low-pressure sensor P2 is a sensor that is arranged in the suction side (low pressure side) piping of the compressor 11 and can detect the refrigerant pressure in the suction side piping. The discharge temperature sensor T1 is a sensor that is disposed near the discharge port of the compressor 11 and can detect the temperature of the discharge gas.

The check valve V <b> 1 is provided between the discharge side of the compressor 11 and the condenser C, and prevents a reverse flow of refrigerant gas from the condenser C to the compressor 11. The expansion valve V2 changes the refrigerant from a high-temperature and high-pressure state through a condenser C to a low-temperature and low-pressure mist through a small hole and makes it easy to suck heat with the evaporator E.
The pressure equalizing on-off valve V3 is provided on a pipe connecting the high pressure side (the discharge side of the compressor 11) and the low pressure side (the suction side of the compressor 11), and is opened so that the high pressure side pipe and the low pressure side valve V3 are opened. Equalize (equalize) the pressure difference with the side pipe.

  According to the configuration shown in FIG. 1, the air conditioner 1 is an engine-driven air conditioner that directly operates the compressor 11 based on the power generated by the rotation of the engine 10. The air conditioner 1 is mounted on, for example, a vehicle for refrigeration transport (a refrigeration transport truck).

(Structure of engine, compressor, etc.)
FIG. 2 is a diagram schematically illustrating the structure of the engine and the compressor according to the first embodiment.
Next, the structure of the engine 10, the compressor 11, etc. will be described with reference to FIG.
As shown in FIG. 2, the first compressor 11 </ b> A and the second compressor 11 </ b> B are attached to the engine 10. The engine 10 rotates by rotating the rotating body 10a by the combustion of the fuel, so that the rotational force is transmitted to the compressors 11 through the belts B1 and B2 which are power transmission systems.
Here, the belt B1 connects the rotating body 10a and the first electromagnetic clutch 12A. Therefore, when the first electromagnetic clutch 12A is connected, the rotational force of the rotating body 10a is transmitted to the first compressor 11A through the belt B1 and the first electromagnetic clutch 12A. Similarly, the belt B2 connects the rotating body 10a and the second electromagnetic clutch 12B. Therefore, when the second electromagnetic clutch 12B is connected, the rotational force of the rotating body 10a is transmitted to the second compressor 11B through the belt B2 and the second electromagnetic clutch 12B.
As described above, the air conditioner 1 can operate the plurality of compressors 11 by the rotation of one engine 10, and can control a desired compression among the plurality of compressors 11 by controlling the electromagnetic clutch 12. Air conditioner operation can be performed by selecting a machine.

  The rotation speed detection sensor R1 outputs a pulse signal corresponding to the rotation speed of the engine 10 (rotating body 10a). The operation control unit 13 can detect the rotational speed (rpm) of the engine 10 per unit time based on the frequency of the pulse signal and the like.

(Processing flow of failure judgment unit)
3 and 4 are first and second diagrams, respectively, showing the processing flow of the failure determination unit according to the first embodiment.
Next, the processing flow of the failure determination unit 130 will be described step by step with reference to FIGS. 3 and 4. The processing flow of the failure determination unit 130 is executed when an abnormality is detected during operation of the air conditioner 1 (step S01).

  The failure determination unit 130 monitors various detection signals from the low pressure sensor P1, the high pressure sensor P2, the discharge temperature sensor T1, and the rotation speed detection sensor R1 during the operation of the air conditioner 1. Here, the failure determination unit 130 detects, for example, an engine stall, an abnormal decrease in the engine speed, an abnormal fluctuation in pressure on the high pressure side or the low pressure side (see FIG. 1), and the like (step S01).

The failure determination unit 130 immediately stops the air conditioning operation when detecting an abnormality in the air conditioning operation (step S02). Here, the failure determination unit 130 stops the operation of the engine 10 when the engine 10 is operating. Moreover, the failure determination part 130 makes both the 1st electromagnetic clutch 12A and the 2nd electromagnetic clutch 12B a disconnection state.
Next, the failure determination unit 130 performs pressure equalization processing by controlling the pressure equalization on / off valve V3 to open (step S03). Thereby, the pressure on the high pressure side or the low pressure side (see FIG. 1) is equalized.

  Next, failure determination unit 130 attempts to start engine 10 (step S04) and determines whether engine 10 has started normally (step S05). Here, the engine 10 is in a state (no load state) separated from both the first compressor 11A and the second compressor 11B. Therefore, when the engine 10 has not started normally (step S05: NO), it is determined that some kind of trouble (failure) has occurred in the engine 10, and the process is terminated. At this time, the failure determination unit 130 may perform notification processing (error display, lamp lighting, etc.) indicating that a trouble has occurred in the engine 10 to the operator.

On the other hand, when the engine 10 has started normally (step S05: YES), the failure determination unit 130 performs failure determination processing for the first compressor 11A (step S06). The failure determination unit 130 determines whether the first compressor 11A is “failure” or “normal” through this failure determination process. The failure determination process will be separately described in detail with reference to FIG.
When the failure determination process for the first compressor 11A is completed, the failure determination unit 130 opens the pressure equalization on-off valve V3 and performs the pressure equalization process again (step S07).
Subsequently, the failure determination unit 130 performs failure determination processing for the second compressor 11B (step S08). The failure determination unit 130 determines whether the second compressor 11B is “failure” or “normal” through this failure determination process.

The failure determination unit 130 determines whether or not all of the first compressor 11A and the second compressor 11B are “failed” (step S09). Here, when all of the first compressor 11A and the second compressor 11B are “failed” (step S09: YES), the failure determination unit 130 determines that the air conditioning operation of the air conditioner 1 cannot be continued. To finish the process. At this time, the failure determination unit 130 may perform notification processing indicating to the operator that all the compressors 11 have failed.
On the other hand, if either one or both of the first compressor 11A and the second compressor 11B is “normal” (step S09: NO), the “normal” compressor 11 is selected. The air conditioning operation is restarted (step S10).

FIGS. 5 and 6 are a first diagram and a second diagram, respectively, for explaining the failure determination processing of the failure determination unit according to the first embodiment.
Next, the failure determination process in step S06 (FIG. 3) will be described in detail with reference to FIG. 4, FIG. 5, and FIG.
First, at the time of step S06, both the first electromagnetic clutch 12A and the second electromagnetic clutch 12B are in a disconnected state, and the engine 10 is rotating with no load. Here, the failure determination unit 130 first connects the first electromagnetic clutch 12A for a short time, and performs short-time connection that immediately returns to the disconnected state (step S11). Then, failure determination unit 130 determines whether or not the detected rotation speed (rpm) of engine 10 has fallen below a predetermined determination threshold TH in the short-time connection through a pulse signal from rotation speed detection sensor R1. (Step S12).

Here, a description will be given of a variation with time of a normal engine speed (rpm) that occurs when the electromagnetic clutch 12 is connected, for example, at the start of an air conditioning operation.
The graph shown in FIG. 5 shows the temporal variation characteristic of the engine speed (rpm) at the normal time before and after the first electromagnetic clutch 12A is connected.

  First, consider the case where the operation control unit 13 outputs the control signal D indicating “OFF” to the first electromagnetic clutch 12A and the second electromagnetic clutch 12B before the start of the air conditioning operation (time 0 in FIG. 5). . In this case, the first electromagnetic clutch 12A and the second electromagnetic clutch 12B are disconnected in response to the control signal D that is “OFF”, and the power transmission system (belts B1, B2) is disconnected. Therefore, at this time, the engine 10 is disconnected from the first compressor 11A and the second compressor 11B and is unloaded.

As shown in FIG. 5, at the time of no load (time 0), the rotational speed (rpm) of the engine 10 per unit time is controlled to be relatively high (for example, around 1600 rpm) and stabilized.
Next, it is assumed that the operation control unit 13 switches the control signal D for the first electromagnetic clutch 12A from “OFF” to “ON” at a certain time t1 (> 0) in order to start the air conditioning operation. Then, the first electromagnetic clutch 12A is connected according to the control signal D, and the first compressor 11A is added as a load to the engine 10 that has been rotating without load. Therefore, after the time t1, the rotational speed of the engine 10 decreases. When the first compressor 11A operates normally, as shown in FIG. 5, the rotational speed of the engine 10 decreases monotonously over a predetermined time from the time t1, and then slightly lower than that at no load. (For example, around 1500 rpm) and stable.

Next, with reference to the graph shown in FIG. 6, the processes in steps S11 and S12 described above will be described in more detail.
As shown in FIG. 6, at time 0, the operation control unit 13 (failure determination unit 130) sets the control signal D for the first electromagnetic clutch 12A (and the second electromagnetic clutch 12B) to “OFF”. At this time, the engine 10 that has undergone step S04 and step S05 (FIG. 3) is in operation (rotating) with no load.

  Here, in step S11, failure determination unit 130 first switches control signal D for first electromagnetic clutch 12A from “OFF” to “ON” at time t1 during rotation of engine 10. Then, the failure determination unit 130 outputs “ON” for a predetermined time Δt after time t1, and immediately returns it to “OFF”. Here, the specified time Δt is, for example, the transmission of power to the first compressor 11A physically through the first electromagnetic clutch 12A after receiving the control signal D that the first electromagnetic clutch 12A is “ON”. It is a time required until the time is made and is defined as a time as short as possible (for example, Δt = 0.2 seconds).

As shown in FIG. 6, the failure determination unit 130 outputs the control signal D that is “OFF” again after the lapse of the specified time Δt from the time t1, thereby causing the first electromagnetic clutch 12A to be in a disconnected state.
When the first compressor 11A is normal, as shown in the solid line graph of FIG. 6, within the specified time Δt during which the control signal D that is “ON” is output, it is the same as the fluctuation characteristics shown in FIG. Shows a decreasing trend. On the other hand, when the first compressor 11A has failed and is in a rotation locked state (non-rotatable state), the load on the first compressor 11A becomes excessive, so as shown in the dashed line graph in FIG. The engine speed is greatly reduced within the specified time Δt from the moment (time t1 + Δt) when the first electromagnetic clutch 12A is engaged.
Then, for example, the engine speed at time t1 + Δt has a significant difference depending on whether or not the first compressor 11A is in the rotation locked state. Therefore, failure determination unit 130 determines in step S12 whether or not the engine speed at time t1 + Δt is equal to or less than a predetermined determination threshold TH (for example, TH = 1500 rpm).

In FIG. 4, when the engine speed is equal to or less than the determination threshold TH as a result of the short-time connection to the first electromagnetic clutch 12A (step S11) (step S12: YES), the failure determination unit 130 performs the first compression. It is determined that the machine 11A is in the rotation locked state, and it is determined that the first compressor 11A is “failure” (step S13).
On the other hand, as a result of the short-time connection to the first electromagnetic clutch 12A, when the engine speed exceeds the determination threshold value TH (step S12: NO), the failure determination unit 130 indicates that the first compressor 11A is at least rotationally locked. It is determined that it is not in a state (“normal” at this point). Then, the failure determination unit 130 again outputs the control signal D that is “ON” to the first electromagnetic clutch 12A, and starts the operation of the first compressor 11A (step S14).

  When the first compressor 11A operates normally, the discharge-side piping and the suction-side piping (FIG. 5) are equalized by the pressure equalization processing (step S03) according to the suction and discharge processing by the first compressor 11A. 1)) again. The failure determination unit 130 monitors the pressure fluctuation based on the operation of the first compressor 11A through the high pressure sensor P1 and the low pressure sensor P2, and determines whether or not there is an abnormality in the pressure fluctuation on the discharge side and the suction side. (Step S15). Specifically, for example, the failure determination unit 130 determines whether or not the detected pressure values on the discharge side and the suction side are consistent with fluctuations assumed during normal operation.

If there is an abnormality in the pressure fluctuation on the discharge side and the suction side (step S15: YES), there is some abnormality in the operation of the first compressor 11A (for example, sufficient power is not transmitted through the belt B1). The first compressor 11A is determined as “failure” (step S13).
On the other hand, when there is no abnormality in the pressure fluctuation on the discharge side and the suction side (step S15: NO), the failure determination unit 130 determines that the first compressor 11A is “normal” (step S16).
After determining “normal” in step S16 or determining “failure” in step S13, the failure determination unit 130 disconnects the first electromagnetic clutch 12A and stops the operation of the first compressor 11A ( Step S17).
As described above, the failure determination unit 130 completes the failure determination process (step S06 (FIG. 3)) for the first compressor 11A through the processes of steps S11 to S17.
The failure determination unit 130 performs the same process as the above-described steps S11 to S17 also in the failure determination process (step S08 (FIG. 3)) for the second compressor 11B.
Moreover, when the failure determination unit 130 determines in step S12 that the first compressor 11A is in the rotation locked state (failure), the pressure equalization process in step S07 (FIG. 3) may be omitted. .

(Function and effect)
As described above, according to the air conditioner 1 according to the first embodiment, the failure determination unit 130 controls the electromagnetic clutch 12 to connect the transmission system for the predetermined time Δt during the rotation of the engine 10. The presence or absence of a failure in the compressor 11 is determined based on the fluctuation in the rotational speed of the engine 10 within the specified time Δt (see steps S11 and S12 (FIG. 4)).

Here, when the compressor 11 is in the rotation locked state, if the electromagnetic clutch 12 is connected and the compressor 11 is forced to operate, slipping of the belts B1 and B2 occurs, and the power transmission system is excessive. May cause damage and damage.
However, as described above, the electromagnetic clutch 12 is connected only for a minimum time (that is, the specified time Δt) in which it can be determined whether or not the compressor 11 to be determined is in the rotation locked state. . Therefore, even if the compressor 11 is in the rotation locked state, it is possible to suppress the maximum load on the power transmission system.

  Further, when the compressor 11 in the rotation locked state is forcibly connected and belt slipping or the like occurs, abnormal noise or noise may be generated based on the belt slipping or the like. However, according to the air conditioner 1 which concerns on 1st Embodiment, since the connection of the electromagnetic clutch 12 is stopped in the minimum time as mentioned above, generation | occurrence | production of abnormal noise and noise is suppressed. Therefore, it is possible to prevent unnecessary anxiety, operation mistakes, and the like from being caused to the operator of the air conditioner 1 (for example, the driver of a vehicle for refrigerated transport) due to generation of abnormal noise and noise.

  Moreover, according to the air conditioner 1 which concerns on 1st Embodiment, since it can be determined in a very short time whether the compressor 11 exists in a rotation lock state, failure determination processing can be performed rapidly.

Moreover, when it determines with the air conditioner 1 which concerns on 1st Embodiment not having a failure of the compressor 11 based on the fluctuation | variation of the rotation speed of the engine 10, it connects a transmission system further and the compressor 11 is further connected. Is operated, and the presence or absence of a failure in the compressor 11 is determined based on the pressure fluctuation according to the operation of the compressor 11 (see steps S14 and S15 (FIG. 4)).
By doing in this way, even if the abnormality of the symptom different from the rotation lock state occurs in the compressor 11, whether or not the pressure fluctuation on the discharge side and the suction side of the compressor 11 is made normal is determined. Judgment can be made appropriately. Therefore, the accuracy of the failure determination of the compressor 11 can be improved.

In addition, the air conditioner 1 according to the first embodiment includes the plurality of compressors 11 (the first compressor 11A and the second compressor 11B) as described above, and the failure determination unit 130 performs one compression. After determining the presence / absence of a failure in the machine 11, the presence / absence of a failure in another compressor 11 is determined.
By doing in this way, when operating the some compressor 11 with the single engine 10, it can be discriminate | determined appropriately which of the some compressors 11 is out of order.

The air conditioner 1 according to the first embodiment further includes a pressure equalizing on-off valve V3 provided on a pipe connecting the discharge side and the suction side of the compressor 11, and the failure determination unit 130 includes After determining whether or not there is a failure in the compressor, the pressure equalizing process is performed on the pressure fluctuated based on the operation of the compressor using the pressure equalizing on-off valve V3 (see step S07 (FIG. 3)).
By doing in this way, initialization (pressure equalization) is performed at the time of the failure determination processing of the other compressor 11 following the failure determination processing of the one compressor 11. In the failure determination process, the accuracy of failure determination based on pressure fluctuation can be increased.

In the air conditioner 1 according to the first embodiment, the operation control unit 13 selects an operable (normal) compressor 11 from the plurality of compressors 11 based on the determination result by the failure determination unit 130. At the same time, the selected compressor 11 is operated to restart the air conditioning operation (see step S10 (FIG. 3)).
By doing in this way, even if any one of the plurality of compressors 11 has failed, the compressor 11 that is automatically determined to be operable (normal) is selected and immediately air-conditioned. Resume operation. Therefore, the air conditioner 1 can suppress that the air conditioning operation is stopped due to the failure of the compressor 11 and the quality of the object to be cooled (frozen food, fresh food, etc.) is impaired.
In addition, when the air conditioner 1 is mounted on a vehicle for refrigerated transport, even if a failure of one compressor 11 occurs and the air conditioning operation is stopped, the driver (the operator of the air conditioner 1) does not do anything. Therefore, it is possible to immediately return to the normal air-conditioning operation without paying for this, so that not only the quality maintenance performance of the object to be cooled can be improved, but also the efficiency of the transportation work can be improved.

  As described above, the air conditioner 1 according to the first embodiment can easily determine the presence or absence of a failure in the compressor 11 without applying an excessive load to the power transmission system.

<Other embodiments>
As mentioned above, although 1st Embodiment was described in detail, the specific aspect of the air conditioner 1 which concerns on each embodiment is not limited to the above-mentioned thing, In the range which does not deviate from a summary, various designs It is possible to make changes.

  For example, although the air conditioner 1 according to the first embodiment has been described as having two compressors 11, the present embodiment is not limited to this mode in other embodiments. In other words, the air conditioner 1 according to another embodiment may have three or more compressors 11. In this case, the failure determination unit 130 sequentially performs failure determination processing (steps S06 and S08) for each of the three or more compressors 11.

Moreover, the air conditioner 1 which concerns on 1st Embodiment demonstrated as what restarts an air conditioning driving | operation using the other compressor 11 which can operate | move, when either one of the two compressors 11 fails. Here, the air conditioner 1 according to another embodiment may further perform notification processing indicating to the operator that a failure has occurred in one compressor 11 that has resumed air conditioning operation.
As a result, the driver (operator) can recognize that one compressor 11 is out of order and, for example, after a transportation operation, it is necessary to take care of failure diagnosis, repair, and the like. Moreover, since the two compressors 11 cannot be driven simultaneously, it can be recognized that a high cooling capacity cannot be exhibited.

Further, the failure determination unit 130 according to the first embodiment first determines whether or not the compressor 11 is in the rotation locked state (see step S12 (FIG. 4)), and is determined not to be in the rotation locked state. It is determined whether or not the compressor 11 is functioning normally based on the pressure fluctuation (
Step S15 (see FIG. 4) is described. However, other embodiments are not limited to this aspect.
For example, the failure determination unit 130 according to another embodiment adds to the compressor 11 based on the temperature detection value acquired through the discharge temperature sensor T1 in addition to the process of step S15 (or instead of the process of step S15). It may be determined whether or not is a failure.

Further, the failure determination unit 130 according to the first embodiment performs the engine speed after the short-time connection (time t1 + Δt (FIG. 6)) in the short-time connection processing of the electromagnetic clutch 12 (see step S11 (FIG. 4)). It is assumed that the connection is made only for the minimum time (specified time Δt) in which a significant difference appears.
Here, the failure determination unit 130 according to another embodiment further sets the upper limit value of the specified time Δt to the maximum value at which the engine 10 does not stall even if the determination target compressor 11 is in the rotation locked state. It may be defined as time.
By doing in this way, even if the compressor 11 is in the rotation locked state, the load is disconnected before the engine stall occurs, and the rotation of the engine 10 is continued even after the short-time connection process. Processing can be performed quickly.

In each of the above-described embodiments, a program for realizing various functions of the failure determination unit 130 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system. Various processes are performed by executing. Here, various processes of the failure determination unit 130 described above are stored in a computer-readable recording medium in the form of a program, and the above-described various processes are performed by the computer reading and executing the program. The computer-readable recording medium is a magnetic disk, a magneto-optical disk, a CD-ROM, a DVD-ROM, a semiconductor memory, or the like. Alternatively, the computer program may be distributed to the computer via a communication line, and the computer that has received the distribution may execute the program.
Moreover, the aspect with which the various functions of the failure determination part 130 are comprised in the one or some apparatus connected by a wireless network etc. may be sufficient.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof, as long as they are included in the scope and gist of the invention.

DESCRIPTION OF SYMBOLS 1 Air conditioner 10 Engine 10a Rotating body 11 Compressor 11A 1st compressor 11B 2nd compressor 12 Electromagnetic clutch (power transmission device)
12A 1st electromagnetic clutch (power transmission device)
12B Second electromagnetic clutch (power transmission device)
13 Operation control unit 130 Failure determination unit P1 Low pressure sensor P2 High pressure sensor T1 Discharge temperature sensor R1 Rotational speed detection sensor V1 Check valve V2 Expansion valve V3 Pressure equalizing on / off valve C Capacitor E Evaporator

Claims (8)

Engine,
A compressor that operates based on power generated by rotation of the engine;
A power transmission device capable of connecting and disconnecting a power transmission system from the engine to the compressor;
An air conditioner comprising:
The power transmission device is controlled to connect the transmission system for a predetermined time during rotation of the engine, and the compressor malfunctions based on fluctuations in the engine speed within the predetermined time. Air conditioner equipped with a failure determination unit that determines the presence or absence. The failure determination unit
When it is determined that there is no failure of the compressor based on the fluctuation of the rotation speed, the pressure or discharge temperature corresponding to the operation of the compressor is further operated by connecting the transmission system and operating the compressor. The air conditioner of Claim 1. The presence or absence of the failure in the said compressor is determined based on the fluctuation | variation of this. Comprising a plurality of said compressors;
The failure determination unit
The air conditioner according to claim 1, wherein after determining whether or not there is a failure in one of the compressors, it is determined whether or not there is a failure in the other compressor. A pressure equalizing on / off valve disposed on a pipe connecting the discharge side and the suction side of the compressor;
The failure determination unit
The air conditioner according to claim 3, wherein after determining whether or not there is a failure in one of the compressors, the pressure equalizing on / off valve is opened to perform pressure equalization processing on the pressure that varies based on the operation of the compressor. The air conditioner according to claim 3 or 4, wherein a normal compressor is selected from the plurality of compressors based on a determination result by the failure determination unit, and the selected compressor is operated.   A vehicle comprising the air conditioner according to any one of claims 1 to 5. Engine,
A compressor that operates based on power generated by rotation of the engine;
A power transmission device capable of connecting and disconnecting a power transmission system from the engine to the compressor;
A failure detection method for detecting the presence or absence of a failure in an air conditioner comprising:
The power transmission device is controlled to connect the transmission system for a predetermined time during the rotation of the engine, and the compressor malfunctions based on fluctuations in the engine speed within the predetermined time. A method for detecting a failure of an air conditioner, comprising the step of determining the presence or absence of an air conditioner. Engine,
A compressor that operates based on power generated by rotation of the engine;
A power transmission device capable of connecting and disconnecting a power transmission system from the engine to the compressor;
Air conditioner computer equipped with
The power transmission device is controlled to connect the transmission system for a predetermined time during rotation of the engine, and the compressor malfunctions based on fluctuations in the engine speed within the predetermined time. A program that functions as a failure determination means for determining the presence or absence of a fault

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