BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention relates to an engine driving type air conditioner for variably
controlling the rotational number of an engine and circulating refrigerant discharged
from a compressor driven by the engine to thereby carry out an air conditioning operation
and a method of controlling the engine driving type air conditioner, and also relates
to an overload control operation of the engine.
2. Description of the Related Art
[0002] There has been hitherto known a so-called engine driving type air conditioner in
which a compressor of an outdoor unit is driven by an engine using gas or the like
as fuel to compress and circulate refrigerant.
[0003] In some of this type of engine driving type air conditioners, the engine rotational
number is variably controlled in accordance with an air conditioning load, the discharge
pressure of the refrigerant at the exit of the compressor, the suction pressure of
the refrigerant at the entrance of the compressor and the temperature at the refrigerant
inlet/outlet port of a heat exchanger are measured, the shaft output of the compressor
is calculated from the measurement result and then it is judged on the basis of the
shaft output whether the engine is under overload state or not (for example,
JP-A-6-137701).
[0004] When the engine load is estimated from the shaft output of the compressor as described
above, it is required to consider the volumetric efficiency and power efficiency of
the compressor. However, the volumetric efficiency and power efficiency of the compressor
are not fixed, and some difference which is not negligible occurs in accordance with
the rotational velocity of the compressor or refrigerant pressure. Therefore, there
has been a problem that it is difficult to estimate the engine load with high precision.
[0005] EP 1 334 852 A2 discloses an engine driving type air conditioner according to the preamble of claim
1.
[0006] US 5,454,229 A describes a refrigeration unit in which a control unit receives inputs from sensors
including an engine RPM-sensor.
SUMMARY OF THE INVENTION
[0007] Therefore, the present invention has been implemented in view of the foregoing situation,
and has an object to provide an engine driving type air conditioner and a control
method therefore in which it is accurately judged whether an engine is under overload
state or not, and the overload state of the engine can be properly avoided on the
basis of the judgment result.
[0008] In order to attain the above object, according to a first aspect of the present invention,
an engine driving type air conditioner that is equipped with a compressor driven by
an engine, an outdoor unit having an outdoor heat exchanger, an outdoor expansion
valve and an outdoor fan and an indoor unit having an indoor heat exchanger, an indoor
expansion valve and an indoor fan, and variably controls the rotational number of
an engine in accordance with an air conditioning load and circulating
refrigerant discharged from the compressor between the outdoor heat exchanger and
the indoor heat exchanger to thereby carry out an air conditioning operation, comprises:
a judging unit for achieving information on at least one of the rotational number
of the engine, the opening degree of a fuel adjusting valve and the opening degree
of a throttle, and judging on the basis of the information thus achieved whether the
engine to be controlled in accordance with an air conditioning load is under overload
state or not; and a control unit for carrying out engine load reducing control of
reducing the load of the engine if it is judged by the judging unit that the engine
is under overload state.
[0009] According to a second aspect of the present invention, the above engine driving type
air conditioner further comprises a storage unit for mapping at least one of the rotational
number of the engine, the opening degree of the fuel adjusting valve and the opening
degree of the throttle and at least one of the torque value of the engine, an ignition
demand voltage and an excess air factor in association with each other and storing
a mapping result, wherein the judging unit refers to the information stored in the
storage unit to specify at least one of the torque value of the engine, the ignition
demand voltage and the excessive air factor on the basis of the information thus achieved,
compares the specified value with a predetermined setting value and judges on the
basis of the comparison result whether the engine is under overload state.
[0010] According to a third aspect of the present invention, the above engine driving type
air conditioner further comprises a storage unit for storing a calculation equation
of calculating at least one of the torque value of the engine, an ignition demand
voltage and an excess air factor from at least one of the rotational number of the
engine, the opening degree of the fuel adjusting valve and the opening degree of the
throttle, wherein the judging unit specifies at least one of the torque value of the
engine, the ignition demand voltage and the excessive air factor on the basis of the
information thus achieved by using the calculation equation stored in the storage
unit, compares the specified value with a predetermined setting value and judges on
the basis of the comparison result whether the engine is under overload state.
[0011] According to a fourth aspect of the present invention, the above engine driving type
air conditioner further comprises a bypass pipe connected between a refrigerant high
pressure side and a refrigerant lowpressure side with respect to the compressor to
return apart of the refrigerant at the refrigerant high pressure side of the compressor
to the refrigerant low pressure side of the compressor, and a bypass valve disposed
in the bypass pipe to adjust the refrigerant amount to be returned, wherein when it
is judged that the engine is under overload state, the control unit carries out at
least one of adjustment of the expansion valve corresponding to one heat exchanger
functioning as an evaporator out of the outdoor heat exchanger and the indoor heat
exchanger, adjustment of the rotational velocity of the fan corresponding to the other
heat exchanger functioning as a condenser out of the outdoor heat exchanger and the
indoor heat exchanger, adjustment of the rotational number of the engine and adjustment
of the opening degree of the bypass valve in the bypass pipe provided between the
refrigerant high pressure side and the refrigerant low pressure side.
[0012] According to a fifth aspect of the present invention, in the above engine driving
type air conditioner, wherein in accordance with the air conditioning load, the control
unit changes at least one of the lower limit value of the opening degree of the expansion
valve corresponding to the heat exchanger functioning as the evaporator when the opening
degree concerned is adjusted, the upper limit value of the rotational velocity of
the fan corresponding to the heat exchanger functioning as the condenser when the
rotational velocity concerned is adjusted, the lower limit value of the rotational
number of the engine when the rotational number of the engine is adjusted, and the
upper limit value of the opening degree of the bypass valve when the opening degree
concerned is adjusted.
[0013] According to a sixth aspect of the present invention, a method of controlling an
engine driving type air conditioner that is equipped with a compressor driven by an
engine, an outdoor unit having an outdoor heat exchanger, an outdoor expansion valve
and an outdoor fan and an indoor unit having an indoor heat exchanger, an indoor expansion
valve and an indoor fan, and variably controls the rotational number of an engine
in accordance with an air conditioning load and circulating refrigerant discharged
from the compressor between the outdoor heat exchanger and the indoor heat exchanger
to thereby carry out an air conditioning operation, comprising the steps of: achieving
information on at least one of the rotational number of the engine, the opening degree
of a fuel adjusting valve and the opening degree of a throttle; judging on the basis
of the information thus achieved whether the engine to be controlled in accordance
with an air conditioning load is under overload state or not; and carrying out engine
load reducing control of reducing the load of the engine if it is judged that the
engine is under overload state.
[0014] According to a seventh aspect of the present invention, the above method further
comprises the steps of: mapping at least one of the rotational number of the engine,
the opening degree of the fuel adjusting valve and the opening degree of the throttle
and at least one of the torque value of the engine, an ignition demand voltage and
an excess air factor in association with each other; creating a data base from the
mapping result; referring to the data base to specify at least one of the torque value
of the engine, the ignition demand voltage and the excessive air factor from the information
on at least one of the rotational number of the engine, the opening degree of the
fuel adjusting valve and the opening degree of the throttle; comparing the specified
value with a predetermined setting value; and judging on the basis of the comparison
result whether the engine is under overload state.
[0015] According to an eighth aspect of the present invention, the above method further
comprises the steps of: creating a calculation equation of calculating at least one
of the torque value of the engine, an ignition demand voltage and an excess air factor
from at least one of the rotational number of the engine, the opening degree of the
fuel adjusting valve and the opening degree of the throttle; specifying at least one
of the torque value of the engine, the ignition demand voltage and the excessive air
factor on the basis of the information on at least one of the rotational number of
the engine, the opening degree of the fuel adjusting valve and the opening degree
of the throttle by using the calculation equation; comparing the specified value with
a predetermined setting value; and judging on the basis of the comparison result whether
the engine is under overload state.
[0016] According to a ninth aspect of the present invention, in the above method wherein
the air conditioner further comprises a bypass pipe connected between a refrigerant
high pressure side and a refrigerant low pressure side with respect to the compressor
to return apart of the refrigerant at the refrigerant high pressure side of the compressor
to the refrigerant low pressure side of the compressor, and a bypass valve disposed
in the bypass pipe to adjust the refrigerant amount to be returned, and when it is
judged that the engine is under overload state, at least one of adjustment of the
expansion valve corresponding to one heat exchanger functioning as an evaporator out
of the outdoor heat exchanger and the indoor heat exchanger, adjustment of the rotational
velocity of the fan corresponding to the other heat exchanger functioning as a condenser
out of the outdoor heat exchanger and the indoor heat exchanger, adjustment of the
rotational number of the engine and adjustment of the opening degree of the bypass
valve in the bypass pipe provided between the refrigerant high pressure side and the
refrigerant low pressure side.
[0017] According to a tenth aspect of the present invention, the above method further comprises
a step of, in accordance with the air conditioning load, changing at least one of
the lower limit value of the opening degree of the expansion valve corresponding to
the heat exchanger functioning as the evaporator when the opening degree concerned
is adjusted, the upper limit value of the rotational velocity of the fan corresponding
to the heat exchanger functioning as the condenser when the rotational velocity concerned
is adjusted, the lower limit value of the rotational number of the engine when the
rotational number of the engine is adjusted, and the upper limit value of the opening
degree of the bypass valve when the opening degree concerned is adjusted.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018]
Fig. 1 is a diagram showing the construction of an engine driving type air conditioner
according to an embodiment;
Fig. 2 is block diagram showing the construction of a control device;
Fig. 3 is a diagram showing a data base; and
Fig. 4 is a flowchart showing engine load reducing processing.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] Preferred embodiments according to the present invention will be described hereunder
with reference to the accompanying drawings.
[0020] Fig. 1 is a diagram showing the construction of an engine driving type air conditioner
100 according to an embodiment.
[0021] The engine driving type air conditioner 100 comprises one outdoor unit 1 and a plurality
of (for example, two) indoor units 2a, 2b which are connected to each other through
a refrigerant pipe (inter-unit pipe) 3 comprising a gas pipe 3a and a liquid pipe
3b. The engine driving type air conditioner 100 is further equipped with a control
device 4 for controlling the driving of the air conditioner 100 and an operating unit
5 for carrying out operations such as driving instruction, etc. of the control device
4.
[0022] The operating unit 5 is a so-called remote controller for operating/stopping the
indoor units 2a, 2b, etc., a remote operating device for carrying out various kinds
of settings and the driving state of the indoor units 2a, 2b and the outdoor unit
1 or the like. In this embodiment, the engine driving type air conditioner 100 is
designed so as to circulate alternative refrigerant R410 which is high in refrigerant
performance per unit volume and small in pressure loss.
[0023] The outdoor unit 1 is disposed outdoors. The outdoor unit 1 is equipped with an engine
10 for generating driving force by combusting fuel gas or the like, a compressor 11
which is connected to the engine 10 through a driving force transmitting unit (not
shown) and compressing and discharging the alternative refrigerant R410a, a four-way
valve 12 for inverting the circulation direction of the refrigerant, an outdoor heat
exchanger 13 for carrying out the heat exchange between the refrigerant and the outside
air, an outdoor expansion valve 14 for reducing the pressure of the refrigerant, and
an accumulator 15 for carrying out gas-liquid separation on the refrigerant sucked
in the compressor 11, these elements being connected to one another through the refrigerant
pipe. An outdoor fan 16 for blowing air to the outdoor heat exchanger 13 id disposed
in proximity to the outdoor heat exchanger 13.
[0024] The outdoor unit 1 is equipped with a bypass pipe 17 which is connected between a
refrigerant high-pressure side (the discharge side of the compressor 11) and a refrigerant
low-pressure side (the entrance side of the accumulator 15 in Fig. 1), and a bypass
valve (electrically-operated valve) 18 provided in the bypass pipe. By adjusting the
opening degree of the bypass valve 18, the return amount of a part of the refrigerant
which is discharged from the compressor 11 and returned through the bypass pipe 17
to the suction side of the compressor 11 is adjusted, whereby the circulation amount
of the refrigerant circulated through the outdoor unit 1 and the indoor units 2a,
2b is adjusted.
[0025] Furthermore, the outdoor unit 1 is further equipped with a liquid-refrigerant pipe
40 for suitably supplying liquid-refrigerant flowing through the pipe 19 (corresponding
to the liquid pipe 3b at the outdoor unit 1 side) to the entrance of the accumulator
15 provided at the suction side of the compressor 11, and also a liquid valve (electrically-operated
valve) 41 provided in the liquid pipe 40. The liquid valve 41 is normally closed.
However, when the temperature of the refrigerant discharged from the compressor 11
exceeds a predetermined temperature (this temperature is varied in accordance with
the kind of the refrigerant, and for example it is set to about 115°C or the like),
the liquid valve 41 is opened, and the liquid refrigerant whose temperature is low
is supplied from the pipe 19 at the outdoor unit 1 side through the liquid-refrigerant
pipe 40 to the entrance side of the accumulator 15. Accordingly, the temperature of
the gas refrigerant sucked into the compressor 11 is reduced, and thus overheat of
the refrigerant discharged from the compressor 11 can be prevented.
[0026] The indoor unit 2a, 2b is equipped with an indoor heat exchanger 20a, 20b for carrying
out the heat exchange between the refrigerant and indoor air in a room in which the
indoor unit 2a, 2b is secured, and an indoor expansion valve 21a, 21b for controlling
the refrigerant amount of the refrigerant flowing into the indoor unit 2a, 2b, the
indoor heat exchangers 20a, 20b and the indoor expansion valves 21a, 21b being connected
to one another through the refrigerant pipe. Furthermore, an indoor fan 22a, 22b for
blowing air to the indoor heat exchanger 20a, 20 is disposed in proximity to the indoor
heat exchanger 20a, 20b.
[0027] Furthermore, air-fuel mixture is supplied from an engine fuel supply device 31 into
the combustion chamber of the engine 10 for driving the compressor 11. The engine
fuel supply device 31 includes fuel cutoff valves 33, a zero governor 34, a fuel adjusting
valve 35 and a throttle valve 36 which are successively disposed in a fuel supply
pipe 32 in this order, and the throttle valve 36 is connected to the combustion chamber
of the engine 10. The fuel cutoff valves 33 constitute a close type fuel cutoff valve
mechanism, and one of the cutoff of the fuel gas with no leakage and the intercommunication
of the fuel gas is selectively performed by fully closing or opening the fuel cutoff
valves 33.
[0028] Fig. 2 is a block diagram showing the construction of a control device 4. The control
device 4 is equipped with a setting unit 47 for setting a driving instruction, etc.
to the engine 10 and the compressor 11, EEPROM (storage unit) 42 for storing various
kinds of setting data of the engine driving type air conditioner 100, control programs,
control data and a data base 50 (see Fig. 3), etc., CPU 43 for controlling the whole
of the engine driving type air conditioner 100 on the basis of the control programs,
etc. stored in EEPROM 42, RAM 44 for temporarily storing various kinds of data, a
transceiver 45 for making communications with the operating unit 5, and an interface
(I/F) 46 for transmitting/receiving signals to/from the respective units of the engine
driving type air conditioner 100.
[0029] The control device 4 is further connected through the I/F 46 to a rotational number
detector (not shown) for detecting the rotational number of the engine 10, and temperature
sensors (an indoor temperature sensor for measuring the indoor temperature (not shown),
temperature sensors for measuring the refrigerant temperature at the inlet/outlet
ports of each of the heat exchangers 13, 20a, 20b (not shown), and temperature sensors
23a, 23b for measuring the air blow-out temperature of the indoor fans 22a, 22b of
the indoor units 2a, 2b (not shown)), and it is designed so as to achieve the information
on the rotational number of the engine and the temperature at each place.
[0030] When the operating unit 5 is manipulated, the control device 4 controls each of the
engine 10, the four-way valve 12, the outdoor expansion valve 14 and the outdoor fan
16 of the outdoor unit 1 and the indoor expansion valves 21a, 21b and the indoor fans
22a, 22b of the indoor units 2a, 2b.
[0031] Specifically, the control device 4 switches the four-way valve 12 to set the air
conditioner 1 to cooling operation or heating operation. That is, when the four-way
valve 12 is switched to the cooling side, the refrigerant flows as indicated by a
broken-line arrow, the outdoor heat exchanger 13 functions as a condenser and the
indoor heat exchangers 20a, 20b function as evaporators, so that the operation state
of the air conditioner is set to a cooling operation state and each of the indoor
heat exchangers 20a, 20b cools a room. When the control device 4 switches the four-way
valve 12 to the heating side, the refrigerant flows as indicated by a solid-line arrow,
the indoor heat exchangers 20a, 20b function as condensers and the outdoor heat exchanger
13 functions as an evaporator, so that the operation state of the air conditioner
is set to a heating operation state and each of the indoor heat exchangers heats a
room.
[0032] Furthermore, the control device 4 controls the opening degrees of the fuel adjusting
valve 35 and throttle valve 36 (the fuel adjusting valve opening degree, the throttle
opening degree) on the basis of the difference between the set temperature set by
the operating unit 5 and the indoor temperature achieved from the indoor temperature
sensor, etc. to variably control the rotational number of the engine 10, and also
it controls the opening degrees of the outdoor expansion valve 14 and indoor expansion
valves 21a, 21b on the basis of the refrigerant temperature difference between the
refrigerant inlet/outlet ports of the heat exchangers 13, 20a, 20b.
[0033] Under the air conditioning operation, the control device 4 judges whether the engine
10 controlled in accordance with the air conditioning load is under overload state
or not. If it is judged that the engine 10 is under overload state, the control device
4 carried out the processing of reducing the engine load (the engine load reducing
processing) . In this embodiment, the control device 4 achieves information indicating
the present control state of the engine 10 (control information) such as the rotational
number of the engine 10, the fuel adjusting valve opening degree and the throttle
opening degree, refers to a data base 50 on the basis of these information and judges
whether the engine 10 is under overload state or not. Fig. 3 shows an example of a
data base 50.
[0034] The data base 50 describes the engine number of the engine, the fuel adjusting valve
opening degree, the throttle opening degree, the torque value of the engine, the engine
heat efficiency, the IG (ignition) demand voltage, the fuel gas flow amount and λ
(excess air factor) in association with one another. The engine rotational number,
the fuel adjusting valve opening degree and the throttle opening degree are measurable
information under control of the engine 10, and the torque value, the IG demand voltage
and λ are information needed to judge whether the engine 10 is under overload state
or not. That is, if the torque value is excessively large, the durability of the engine
is lowered. If the IG demand voltage is high, the coil lifetime is lowered. Furthermore,
if λ is reduced, knocking occurs and the engine may be damaged. That is, these information
is information for specifying a situation that the engine load is high (load specifying
information). Furthermore, the engine heat efficiency is information for judging whether
the engine is driven at a rotational speed which provides an excellent engine heat
efficiency under power saving operation. Furthermore, the fuel gas flow amount is
information suitably used under gas demand control or under power saving operation.
[0035] For example, the data base 50 is achieved as follows. That is, torques of 1, 3, 5,
7, 9, 11 and 13 (Kg·m) are respectively applied as a load to the engine 10, and the
fuel adjusting valve opening degree and the throttle opening degree are adjusted so
that the engine 10 is rotated at 1000 (rpm) under each torque. Furthermore, various
parameters such as the fuel adjusting valve opening degree, the throttle opening degree,
the fuel gas flow amount, the torque value, the engine heat efficiency, the IG demand
voltage, the fuel gas flow amount and λ under the above state are achieved by measurements
or the like. Furthermore, with respect to the engine rotational number of 1200 (rpm),
1400 (rpm), .., 2000 (rpm), the fuel adjusting valve opening degree, the throttle
opening degree, the fuel gas flow amount, the engine heat efficiency, the IG demand
voltage, the fuel gas flow amount and λ under each torque are likewise achieved by
measurements or the like. The measurement data thus achieved are mapped to create
the data base 50. The data base 50 thus achieved is stored in EEPROM 42 of the control
device 42. The creation of the data base 50 is not limited to the actual measurement,
and it may be created by simulation or the like. For example, various parameters as
described above are determined by simulation while the driving condition of the engine
10 is variously varied, and the data base 50 is created on the basis of these parameters.
[0036] Fig. 4 is a flowchart showing the engine load reducing processing.
[0037] First, the control device 4 achieves the information on the present engine rotational
number, fuel adjusting valve opening degree and throttle opening degree, refers to
the data base 50 stored in EEPROM 42 and achieves the information on the present torque
value, IG demand voltage and λ on the basis of the engine rotational number, the fuel
adjusting valve opening degree and the throttle opening degree from the data base
50 (step S1). In this case, when the torque value, the IG demand voltage and λ cannot
be directly specified from the data base 50, they may be achieved by carrying out
an interpolative calculation from a driving condition having parameters near to the
present engine rotational number, fuel adjusting valve opening and throttle opening
degree.
[0038] Subsequently, the control device 4 judges on the basis of the torque value, IG demand
voltage and λ thus achieved whether the engine 10 is under overload state or not (step
S2). Specifically, the control device 4 judges whether the torque value is higher
than a predetermined torque upper limit value, whether the IG demand voltage is higher
than a predetermined voltage upper limit value and whether λ is smaller than a predetermined
λ lower limit value. If at least one of these conditions is satisfied, it is judged
that the engine 10 is under overload state. If there is no condition satisfied, it
is judged that the engine 10 is not under overload state.
[0039] If it is judged that the engine 10 is under overload state (step S2: YES), the control
device 4 carries out the engine load reducing processing of reducing the load of the
engine 10.
[0040] The engine load reducing processing will be describedbelow in detail.
[0041] First, the control device 4 judges whether the opening degree of the expansion value
at the evaporator side (the indoor expansion valves 21a, 21b under cooling operation,
the outdoor expansion valve 14 under heating operation) is coincident with a predetermined
lower limit value L1 (step S3). If the opening degree is not coincident with the lower
limit value L1 (if the opening degree is larger than the lower limit value L1), the
control device 4 reduces the opening degree of the expansion valve by a predetermined
amount (step S4). Here, the lower limit value L1 of the expansion valve is set to
such a value that the air conditioning performance is not remarkably degraded, and
by reducing the expansion valve opening degree so that the air conditioning performance
is not remarkably degraded, the circulation amount of the refrigerant can be reduced,
and thus the engine load can be reduced.
[0042] The control device 4 shifts to the processing of step S1 after the expansion valve
opening degree is reduced or if it is judged that the engine 10 is not under overload
state, so that it is continuously judged whether the engine 10 is under overload state
or not. Therefore, the control device 4 gradually reduces the expansion valve opening
degree at the evaporator side and thus gradually reduces the engine load every time
it is judged that the engine 10 is under overload state. Nevertheless, if it is still
judged that the engine 10 is under overload state and the opening degree of the expansion
valve at the evaporator side is reduced till the lower limit value L1 (step S3: lower
limit value L1), the control device 4 shifts to the processing of step S5.
[0043] In the processing of step S5, the control device 4 judges whether the rotational
velocity of the fan at the condenser side (the outdoor fan 16 under cooling operation,
the indoor fans 22a, 22b under heating operation) is coincident with a predetermined
upper limit value U2. If the rotational velocity of the fan is not coincident with
the predetermined upper limit value U2 (if the rotational velocity is smaller than
the upper limit value U2), the control device 4 increases the rotational velocity
of the fan by a predetermined amount (step S6). Here, the upper limit value U2 is
set to the permissible upper limit rotational velocity of the fan or the upper limit
rotational velocity within the permissible range of noise caused by the fan. By increasing
the rotational velocity of the fan as described above, the condensing pressure can
be increased, and the load of the engine 10 can be reduced.
[0044] After the rotational velocity of the fan is increased, the control device 4 shifts
to the processing of the step S1 to gradually increase the rotational velocity of
the fan every time it is judged again that the engine 10 is under overload state.
Nevertheless, if it is judged that the engine 10 is still under overload state and
the rotational velocity of the fan reaches the upper limit value U2 (step S5: upper
limit value U2), the control device 4 shifts to the processing of step S7.
[0045] In the processing of step S7, the control device 4 judges whether the rotational
number of the engine is coincident with the lower limit value L3, and if it is not
coincident with the lower limit value L3 (if it is larger than a lower limit value
L3), the control device reduces the rotational number of the engine by a predetermined
amount (stepS8). Here, the lower limit value L3 is set to such an engine rotational
number that the air conditioning performance is not remarkably degraded. By reducing
the engine rotational number as described above, the compression ratio of the compressor
11 is lowered and thus the engine load can be reduced.
[0046] After the rotational number of the engine 10 is lowered, the control device 4 shifts
to the processing of step S1 to gradually reduce the rotational number of the engine
every time it is judged again that the engine 10 is under overload state. Nevertheless,
if it is judged that the engine 10 is under overload state and the rotational number
of the engine reaches the lower limit value L3 (step S7: lower limit value L3), the
control device 4 shifts to the processing of step S9.
[0047] In the processing of step S9, the control device 4 judges whether the opening degree
of the bypass valve 18 is coincident with a predetermined upper limit value L4. If
it is not coincident with the upper limit value L4 (if it is smaller than the upper
limit value L4), the opening degree of the bypass valve 18 is increased by a predetermined
amount (step S10). Here, the upper limit value L4 is set to such an opening degree
of the bypass valve that the air conditioning performance is not remarkably degraded.
By opening the bypass valve 18 as described above, the compression ratio of the compressor
11 is lowered, and the engine load can be reduced.
[0048] After the bypass valve 18 is opened, the control device 4 shifts to the processing
of step S1 to gradually increase the opening degree of the bypass valve 18 every time
it is judged again that the engine 10 is under overload state. Nevertheless, if it
is judged that the engine 10 is still under overload state, the opening degree of
the bypass valve 18 is finally increased up to the upper limit value L4.
[0049] As described above, when the engine falls into the overload state, the adjustment
of the expansion valve opening degree at the evaporator side, the adjustment of the
speed of the fan at the condenser, the adjustment of the rotational number of the
engine and the adjustment of the bypass valve opening degree are successively carried
out, so that the engine 10 can be returned from the overload state to the normal load
state in some step. However, if it is judged that the engine 10 is still under overload
even when all the steps have been carried out, it may be considered that some abnormality
such as an error or the like occurs in the engine rotational number, the fuel adjusting
valve opening degree and the throttle opening degree achieved. Therefore, the control
device 4 preferably carries out the processing of outputting a predetermined alarm
or the like.
[0050] The upper limit value L1, the upper limit value L2, the lower limit value L3 and
the upper limit value L4 are set to the opening degree of the expansion valve at the
evaporator side, the rotational velocity of the fan at the condenser side, the engine
rotational number and the bypass opening degree at which the air conditioning performance
is not remarkably degraded. If these values are set to fixed values, for example,
if the lower limit value L1 is set in conformity with a case where the air conditioning
load is large, there may occur such a case that the engine load can be reduced without
remarkably degrading the air conditioning performance even when the expansion valve
opening degree is set to a value lower than the lower limit value L1 in the case of
a small air conditioning load. Therefore, the adjustment amount of the engine load
is limited.
[0051] Therefore, according to this embodiment, the control device 4 controls to change
at least one of the lower limit value L1, the upper limit value L2, the lower limit
value L3 and the upper limit value L4 in accordance with the present air conditioning
load. Specifically, the control device 4 achieves the information on the blow-out
air temperature of the indoor units 2a, 2b from the temperature sensors 23a, 23b,
and changes the values L1 to L4 in accordance with the blow-out air temperature. For
example, the control device 4 identifies which one of the following temperature ranges
the blow-out air temperature belongs to under cooling operation: a first temperature
range of 8°C or less, a second temperature range from 8°C to 12°C, a third temperature
range from 12°C to 16°C and a fourth range of 16°C or more, and changes the respective
values L1 to L4 in accordance with the identified temperature range. Accordingly,
each of the opening degree of the expansion value at the evaporator, the rotational
velocity of the fan at the condenser, the engine rotational number and the bypass
valve opening degree can be varied over a broad range. That is, the adjustment amount
of the engine load can be sufficiently secured, and the engine 10 can be more surely
avoided from the overload state.
[0052] As described above, according to the engine driving type air conditioner 100 of this
embodiment, on the basis of the engine rotational number, the fuel adjusting valve
opening degree and the throttle opening degree, it is judged whether the engine 10
is under overload state, whereby the engine load can be judged on the basis of the
present control state of the engine 10. Accordingly, as compared with the case where
it is indirectly judged from the shaft output of the compressor whether the engine
is under overload state or not, it can be judged with high precision whether the engine
10 is under overload state or not.
[0053] Furthermore, when the engine 10 is under overload state, the engine load is reduced
in the following order: reducing the opening degree of the expansion valve at the
evaporator side till the lower limit value L1, increasing the speed of the fan at
the condenser side up to the upper limit value L2, reducing the engine rotational
number till the lower limit value L3 and increasing the opening degree of the bypass
valve 18 up to the upper limit value L4, whereby the engine load can be reduced while
preferentially controlling the opening degree of the expansion valve at the evaporator
side which is generally carried out when the engine load is reduced, and also the
engine 10 can be surely avoided from the overload state.
[0054] Still furthermore, the respective values L1 to L4 are varied I n accordance with
the air conditioning load on a real-time basis, and the adjustment amount of the engine
load can be broadly secured, so that the engine 10 can be more surely avoided from
the overload state.
[0055] The present invention is not limited to the above embodiment. For example, the respective
setting values and the construction of the pipes are not limited to the above embodiment,
and various modifications may be suitably made without departing from the subject
matter of the present invention.
[0056] For example, in the above embodiment, all the information on the engine rotational
number, the fuel adjusting valve opening degree and the throttle opening degree are
achieved, and then it is judged on the basis of these information whether the engine
10 is under overload state. However, it may be modified so that any one or two of
these information is achieved, and then it is judged on the basis of the information
whether the engine 10 is under overload state. In this case, it is also judged from
the actual state (control state) of the engine 10 whether the engine 10 is under overload
state, and thus the overload state of the engine 10 can be judged with higher precision
as compared with the case where the overload state of the engine is indirectly judged
on the basis of the shaft output of the compressor.
[0057] Furthermore, in the above embodiment, the engine rotational number, the fuel adjusting
valve opening degree, the throttle opening degree, the torque value of the engine
10, the engine heat efficiency, the IG demand voltage, the fuel gas flow amount and
λ are mapped to create the data base, and the data base thus created is stored in
the storage unit. However, the engine heat efficiency and the fuel gas flow amount
maybe omitted. Furthermore, experiment data achieved by measuring the engine rotational
number, the fuel adjusting valve opening degree, the throttle opening degree, the
torque value, the IG demand voltage and λ in advance are learned by using a neural
network serving as an information processing mechanism constructed by imitating the
structure of human's brain to create a calculation equation of calculating at least
one of the torque value, the IG demand voltage and λ from at least one of the engine
rotational number, the fuel adjusting valve opening degree and the throttle opening
degree, and the calculation equation thus created is stored in a storage unit. According
to this modification, the use amount of EEPROM 42 can be suppressed.
[0058] Furthermore, in the above embodiment, when the engine 10 is under overload state,
the adjustment of the expansion valve opening degree at the evaporator side, the adjustment
of the speed of the fan at the condenser side, the adjustment of the engine rotational
number and the adjustment of the bypass valve opening degree are successively carried
out. However, all the engine load reducing control steps as described above are not
necessarily carried out, and anyone or plural of the above control steps may be carried
out.
1. An engine driving type air conditioner (100) that is equipped with a compressor (11)
driven by an engine (10), an outdoor unit (1) having an outdoor heat exchanger (13),
an outdoor expansion valve (14) and an outdoor fan (16) and an indoor unit (2a, 2b)
having an indoor heat exchanger (20a, 20b), an indoor expansion valve (21a, 21b) and
an indoor fan (22a, 22b), and variably controls a rotational number of the engine
in accordance with an air conditioning load and circulating refrigerant discharged
from the compressor between the outdoor heat exchanger and the indoor heat exchanger
to thereby carry out an air conditioning operation,
characterized by comprising:
a storage unit (42) configured to store a torque value of the engine, the rotational
number of the engine, an opening degree of a fuel adjusting valve, an opening degree
of a throttle, an ignition demand voltage and an excess air factor in association
with one another;
a control device (4) comprising a judging unit configured to measure the rotational
number of the engine, the opening degree of the fuel adjusting valve and the opening
degree of the throttle under the air conditioning operation, to achieve information
on the torque value of the engine, the ignition demand voltage and the excess air
factor on the basis of the information that is stored in the storage unit and that
is measured under the air conditioning operation and to judge on the basis of the
achieved information whether the engine is under overload state or not; and
a control unit configured to carry out engine load reducing control of reducing the
load of the engine if it is judged by the judging unit that the engine is under overload
state.
2. The engine driving type air conditioner (100) according to claim 1, wherein the storage
unit (42) is configured to store the torque value of the engine, the rotational number
of the engine, the opening degree of the fuel adjusting valve, the opening degree
of the throttle, the ignition demand voltage and the excess air factor achieved by
a measurement while a predetermined torque is applied as a load to the engine, and
the fuel adjusting valve opening degree and the throttle opening degree are adjusted
so that the engine is rotated at a predetermined rotational number.
3. The engine driving type air conditioner (100) according to claim 2, wherein:
the storage unit (42) is configured to map the torque value of the engine, the rotational
number of the engine, the opening degree of the fuel adjusting valve, the opening
degree of the throttle, the ignition demand voltage and the excess air factor achieved
by multiple measurements by varying the torque applied to the engine and the rotational
number of the engine, and to store a mapping result; and
the judging unit refers to the information stored in the storage unit to specify the
torque value of the engine, the ignition demand voltage and the excessive air factor
on the basis of the rotational number of the engine, the opening degree of the fuel
adjusting valve, the opening degree of the throttle measured under the air conditioning
operation, compares the specified value with a predetermined setting value and judges
on the basis of the comparison result whether the engine (10) is under overload state.
4. The engine driving type air conditioner (100) according to any one of claims 1 to
3, wherein:
the storage unit (42) is configured to store a calculation equation of calculating
the torque value of the engine, the ignition demand voltage and the excess air factor
on a basis of the rotational number of the engine, the opening degree of the fuel
adjusting valve and the opening degree of the throttle measured under the air conditioning
operation; and
the judging unit specifies the torque value of the engine, the ignition demand voltage
and the excessive air factor on the basis of the information thus achieved by using
the calculation equation stored in the storage unit, compares the specified value
with a predetermined setting value and judges on the basis of the comparison result
whether the engine (10) is under overload state.
5. The engine driving type air conditioner according to claim 1, further comprising a
bypass pipe (17) connected between a refrigerant high pressure side and a refrigerant
low pressure side with respect to the compressor (11) to return a part of the refrigerant
at the refrigerant high pressure side of the compressor (11) to the refrigerant low
pressure side of the compressor, and a bypass valve (18) disposed in the bypass pipe
to adjust the refrigerant amount to be returned.
6. The engine driving type air conditioner according to claim 5, wherein when it is judged
that the engine is under overload state, the control unit carries out at least one
of adjustment of the expansion valve (14) corresponding to one heat exchanger functioning
as an evaporator out of the outdoor heat exchanger and the indoor heat exchanger,
adjustment of the rotational velocity of the fan corresponding to the other heat exchanger
functioning as a condenser out of the outdoor heat exchanger and the indoor heat exchanger,
adjustment of the rotational number of the engine (10) and adjustment of the opening
degree of the bypass valve in the bypass pipe provided between the refrigerant high
pressure side and the refrigerant low pressure side.
7. The engine driving type air conditioner according to claim 5, wherein in accordance
with the air conditioning load, the control unit changes at least one of the lower
limit value of the opening degree of the expansion valve corresponding to the heat
exchanger functioning as the evaporator when the opening degree concerned is adjusted,
the upper limit value of the rotational velocity of the fan corresponding to the heat
exchanger functioning as the condenser when the rotational velocity concerned is adjusted,
the lower limit value of the rotational number of the engine (10) when the rotational
number of the engine is adjusted, and the upper limit value of the opening degree
of the bypass valve when the opening degree concerned is adjusted.
8. A method of controlling an engine driving type air conditioner (100) that is equipped
with a compressor (11) driven by an engine (10), an outdoor unit (1) having an outdoor
heat exchanger (13), an outdoor expansion valve (14) and an outdoor fan (16) and an
indoor unit (2a, 2b) having an indoor heat exchanger (20a, 20b), an indoor expansion
valve (21a, 21b) and an indoor fan (22a, 22b), and variably controls a rotational
number of an engine in accordance with an air conditioning load and circulating refrigerant
discharged from the compressor between the outdoor heat exchanger and the indoor heat
exchanger to thereby carry out an air conditioning operation,
characterized by comprising the steps of:
storing a torque value of the engine, the rotational number of the engine, an opening
degree of a fuel adjusting valve, an opening degree of a throttle, an ignition demand
voltage and an excess air factor in association with one another;
measuring the rotational number of the engine, the opening degree of the fuel adjusting
valve and the opening degree of the throttle under the air conditioning operation,
to achieve information on the torque value of the engine, the ignition demand voltage
and the excess air factor on the basis of the information that is stored in the storage
unit and that is measured under the air conditioning operation and to judge on the
basis of the achieved information whether the engine is under overload state or not;
and
carrying out engine load reducing control of reducing the load of the engine if it
is judged by the judging unit that the engine is under overload state.
9. The method according to claim 8, wherein the storage step is configured to store the
torque value of the engine, the rotational number of the engine, the opening degree
of the fuel adjusting valve, the opening degree of the throttle, the ignition demand
voltage and the excess air factor achieved by a measurement while a predetermined
torque is applied as a load to the engine, and the fuel adjusting valve opening degree
and the throttle opening degree are adjusted so that the engine is rotated at a predetermined
rotational number.
10. The method according to claim 9, wherein:
the storage step is configured to map the torque value of the engine, the rotational
number of the engine, the opening degree of the fuel adjusting valve, the opening
degree of the throttle, the ignition demand voltage and the excess air factor achieved
by multiple measurements by varying the torque applied to the engine and the rotational
number of the engine, and to store a mapping result; and
the judging step refers to the information stored in the storage unit to specify the
torque value of the engine, the ignition demand voltage and the excessive air factor
on the basis of the rotational number of the engine, the opening degree of the fuel
adjusting valve, the opening degree of the throttle measured under the air conditioning
operation, compares the specified value with a predetermined setting value and judges
on the basis of the comparison result whether the engine (10) is under overload state.
11. The method according to any one of claims 8 to 10, wherein:
the storage step is configured to store a calculation equation of calculating the
torque value of the engine, the ignition demand voltage and the excess air factor
on a basis of the rotational number of the engine, the opening degree of the fuel
adjusting valve and the opening degree of the throttle measured under the air conditioning
operation; and
the judging step specifies the torque value of the engine, the ignition demand voltage
and the excessive air factor on the basis of the information thus achieved by using
the calculation equation stored in the storage unit, compares the specified value
with a predetermined setting value and judges on the basis of the comparison result
whether the engine (10) is under overload state.
12. The method according to claim 8, wherein the air conditioner further comprises a bypass
pipe connected between a refrigerant high pressure side and a refrigerant low pressure
side with respect to the compressor to return a part of the refrigerant at the refrigerant
high pressure side of the compressor to the refrigerant low pressure side of the compressor,
and a bypass valve disposed in the bypass pipe to adjust the refrigerant amount to
be returned, and when it is judged that the engine is under overload state, at least
one of adjustment of the expansion valve corresponding to one heat exchanger functioning
as an evaporator out of the outdoor heat exchanger and the indoor heat exchanger,
adjustment of the rotational velocity of the fan corresponding to the other heat exchanger
functioning as a condenser out of the outdoor heat exchanger and the indoor heat exchanger,
adjustment of the rotational number of the engine and adjustment of the opening degree
of the bypass valve in the bypass pipe provided between the refrigerant high pressure
side and the refrigerant low pressure side.
13. The method according to claim 12, further comprising a step of, in accordance with
the air conditioning load, changing at least one of the lower limit value of the opening
degree of the expansion valve corresponding to the heat exchanger functioning as the
evaporator when the opening degree concerned is adjusted, the upper limit value of
the rotational velocity of the fan corresponding to the heat exchanger functioning
as the condenser when the rotational velocity concerned is adjusted, the lower limit
value of the rotational number of the engine when the rotational number of the engine
is adjusted, and the upper limit value of the opening degree of the bypass valve when
the opening degree concerned is adjusted.
1. Motorbetriebene Klimaanlage (100), die mit einem Kompressor (11), der von einem Motor
(10) betrieben wird, einer Außeneinheit (1) mit einem Außen-Wärmetauscher (13), einem
Außen-Expansionsventil (14) und einem Außengebläse (16) und einer Inneneinheit (2a,
2b) mit einem Innen-Wärmetauscher (20a, 20b), einem Innen-Expansionsventil (21a, 21b)
und einem Innengebläse (22a, 22b) versehen ist und variabel eine Drehzahl des Motors
in Übereinstimmung mit einer Klimatisierungslast steuert und Kühlmittel, das von dem
Kompressor abgegeben wird, zwischen dem Außen-Wärmetauscher und dem Innen-Wärmetauscher
zirkuliert, um dadurch einen Klimatisierungsvorgang durchzuführen,
gekennzeichnet durch:
eine Speichereinheit (42), die ausgebildet ist, um einen Drehmomentwert des Motors,
die Drehzahl des Motors, einen Öffnungsgrad eines Brennstoff-Einstellventils, einen
Öffnungsgrad einer Drossel, eine Zündungs-Anforderungsspannung und einen Luft-Überschussfaktor
in Zuordnung zueinander zu speichern,
eine Steuervorrichtung (4) mit einer Beurteilungseinheit, die ausgebildet ist, um
die Drehzahl des Motors, den Öffnungsgrad des Brennstoff-Einstellventils und den Öffnungsgrad
der Drossel bei dem Klimatisierungsvorgang zu messen,
Informationen hinsichtlich des Drehmomentwerts der Maschine, der Zündungs-Anforderungsspannung
und des Luft-Überschussfaktors auf Grundlage der Informationen, die in der Speichereinheit
gespeichert sind und die bei dem Klimatisierungsvorgang gemessen werden, zu erhalten
und auf Grundlage der erhaltenen Informationen zu beurteilen, ob der Motor in einem
Überlastzustand ist oder nicht, und
eine Steuereinheit, die ausgebildet ist, um eine Motor-Lastreduktionssteuerung zur
Verminderung der Last des Motors durchzuführen, falls durch die Beurteilungseinheit festgestellt wird, dass der Motor in einem Überlastzustand
ist.
2. Motorbetriebene Klimaanlage (100) nach Anspruch 1, wobei die Speichereinheit (42)
ausgebildet ist, um den Drehmomentwert des Motors, die Drehzahl des Motors, den Öffnungsgrad
des Brennstoff-Einstellventils, den Öffnungsgrad der Drossel, die Zündungs-Anforderungsspannung
und den Luft-Überschussfaktor zu speichern, die durch eine Messung erhalten werden,
während ein vorgegebenes Drehmoment als eine Last an den Motor angelegt wird, wobei
der Öffnungsgrad des Brennstoff-Einstellventils und der Drossel-Öffnungsgrad so eingestellt
werden, dass der Motor mit einer vorgegebenen Drehzahl dreht.
3. Motorbetriebene Klimaanlage (100) nach Anspruch 2, wobei:
die Speichereinheit (42) ausgebildet ist, um den Drehmomentwert des Motors, die Drehzahl
des Motors, den Öffnungsgrad des Brennstoff-Einstellventils, den Öffnungsgrad der
Drossel, die Zündungs-Anforderungsspannung und den Luft-Überschussfaktor, die durch
mehrere Messungen durch Variation des an den Motor angelegten Drehmoments und der
Drehzahl des Motors gemessen wurden, zu kartieren und das Kartierungsergebnis zu speichern,
und
die Beurteilungseinheit sich auf die Informationen, die in der Speichereinheit gespeichert
sind, bezieht, um den Drehmomentwert des Motors, die Zündungs-Anforderungsspannung
und den Luft-Überschussfaktor auf Grundlage der Drehzahl des Motors, des Öffnungsgrads
des Brennstoff-Einstellventil, des Öffnungsgrads der Drossel, die bei dem Klimatisierungsvorgang
gemessen wurden, zu spezifizieren, den spezifizierten Wert mit einem vorgegebenen
Einstellwert zu vergleichen und auf Grundlage des Vergleichsergebnisses zu beurteilen,
ob der Motor (10) in einem Überlastzustand ist.
4. Motorbetriebene Klimaanlage (100) nach einem der Ansprüche 1 bis 3, wobei die Speichereinheit
(42) ausgebildet ist, um eine Berechnungsgleichung zur Berechnung des Drehmomentwert
des Motors, der Zündungs-Anforderungsspannung und des Luft-Überschussfaktors auf Grundlage
der Drehzahl des Motors, des Öffnungsgrads des Brennstoff-Einstellventils und des
Öffnungsgrads der Drossel, die bei dem Klimatisierungsvorgang gemessen wurden, zu
speichern und
die Beurteilungseinheit den Drehmomentwert des Motors, die Zündungs-Anforderungsspannung
und den Luft-Überschussfaktor auf Grundlage der Informationen, die so erhalten wurden,
durch Verwendung der Berechnungsgleichung, die in der Speichereinheit gespeichert
ist, zu spezifizieren, den spezifizierten Wert mit einem vorgegebenen Einstellwert
zu vergleichen und auf Grundlage des Vergleichsergebnisses zu beurteilen, ob der Motor
(10) in einem Überlastzustand ist.
5. Motorbetriebene Klimaanlage nach Anspruch 1 mit ferner einer Umgehungsleitung (70),
die zwischen einer Kühlmittel-Hochdruckseite und einer Kühlmittel-Niederdruckseite
bezüglich des Kompressors (11) angeordnet ist, um einen Teil des Kühlmittels an der
Kühlmittel-Hochdruckseite des Kompressors (11) zu der Kühlmittel-Niederdruckseite
des Kompressors zurückzuführen, und einem Umgehungsventil (18), das in der Umgehungsleitung
angeordnet ist, um den zurückzuführenden Anteil des Kühlmittels einzustellen.
6. Motorbetriebene Klimaanlage nach Anspruch 5, wobei, wenn beurteilt wird, dass der
Motor in einem Überlastzustand ist, die Steuereinheit mindestens eines der Einstellung
des Expansionsventils (14) entsprechend einer Wärmetauscherfunktion als einer von
dem Außen-Wärmetauscher und dem Innen-Wärmetauscher, eine Einstellung der Drehgeschwindigkeit
des Gebläses entsprechend dem anderen Wärmetauscher von dem Außen-Wärmetauscher und
dem Innen-Wärmetauscher, der als Kondensor funktioniert, eine Einstellung der Drehzahl
des Motors (10) und eine Einstellung des Öffnungsgrads des Umgehungsventils in der
Umgehungsleitung, die zwischen der Kühlmittel-Hochdruckseite und der Kühlmittel-Niederdruckseite
vorgesehen ist, durchführt.
7. Motorbetriebene Klimaanlage nach Anspruch 5, wobei in Übereinstimmung mit der Klimatisierungslast
die Steuereinheit mindestens eines aus dem unteren Grenzwert des Öffnungsgrades des
Expansionsventils entsprechend dem Wärmetauscher, der als Verdampfer funktioniert,
wenn der betreffende Öffnungsgrad, eingestellt wird, dem oberen Grenzwert der Drehgeschwindigkeit
des Gebläses entsprechend dem Wärmetauscher, der als der Kondensor dient, wenn die
Drehgeschwindigkeit eingestellt wird, dem unteren Grenzwert der Drehzahl des Motors
(10), wenn die Drehzahl des Motors eingestellt wird, und dem oberen Grenzwert des
Öffnungsgrades des Umgehungsventils, wenn der betreffende Öffnungsgrad eingestellt
wird, ändert.
8. Verfahren der Steuerung einer motorbetriebenen Klimaanlage (100), die mit einem Kompressor
(11) ausgestattet ist, der durch einen Motor (10) betrieben wird, einer Außeneinheit
(1) mit einem Außen-Wärmetauscher (13), einem Außen-Expansionsventil (14) und einem
Außengebläse (16) und einer Inneneinheit (2a, 2b) mit einem Innen-Wärmetauscher (20a,
20b), einem Innen-Expansionsventil (21a, 21b) und einem Innengebläse (22a, 22b) und
der eine Drehzahl eines Motors in Übereinstimmung mit einer Klimatisierungslast steuert
und Kühlmittel, das aus dem Kompressor abgegeben wird, zwischen dem Außen-Wärmetauscher
und dem Innen-Wärmetauscher zirkuliert, um dadurch einen Klimatisierungsvorgang zu
steuern,
gekennzeichnet durch die Schritte:
Speichern eines Drehmomentwerts des Motors, der Drehzahl des Motors, eines Öffnungsgrades
eines Brennstoff-Einstellventils, eines Öffnungsgrades einer Drossel, einer Zündungs-Anforderungsspannung
und einem Luft-Überschussfaktor in Zuordnung zueinander,
Messen der Drehzahl des Motors, des Öffnungsgrades des Brennstoff-Einstellventils
und des Öffnungsgrades der Drossel bei dem Klimatisierungsvorgang, um Informationen
hinsichtlich des Drehmomentwerts des Motors, der Zündungs-Anforderungsspannung und
des Luft-Überschussfaktors auf Grundlage der Informationen, die in der Speichereinheit
gespeichert sind und die bei dem Klimatisierungsvorgang gemessen werden, zu erhalten
und aufgrund der erhaltenen Informationen zu beurteilen, ob der Motor in einem Überlastzustand
ist oder nicht, und Durchführen einer Motorlast-Reduktionssteuerung der Reduktion
der Last auf den Motor, falls durch die Beurteilungseinheit beurteilt wird, dass der Motor in einem Überlastzustand ist.
9. Verfahren Anspruch 8, wobei der Speicherschritt ausgebildet ist, um den Drehmomentwert
des Motors, die Drehzahl des Motors, den Öffnungsgrad des Brennstoff-Einstellventils,
den Öffnungsgrad der Drossel, die Zündungs-Anforderungsspannung und den Luft-Überschussfaktor
zu speichern, die durch Messung erhalten werden, während ein vorgegebenes Drehmoment
als eine Last an den Motor angelegt wird, wobei der Öffnungsgrad des Brennstoff-Einstellventils
und der Öffnungsgrad der Drossel so eingestellt werden, dass der Motor mit einer vorgegebenen
Drehzahl dreht.
10. Verfahren nach Anspruch 9, wobei:
der Speicherschritt ausgebildet ist, um den Drehmomentwert des Motors, die Drehzahl
des Motors, den Öffnungsgrad des Brennstoff-Einstellventils, den Öffnungsgrad der
Drossel, die Zündungs-Anforderungsspannung und den Luft-Überschussfaktor, die durch
mehrere Messungen durch Variation des an den Motor angelegten Drehmoments und der
Drehzahl des Motors gemessen wurden, zu kartieren und das Kartierungsergebnis zu speichern,
und
der Beurteilungsschritt sich auf die Informationen, die in der Speichereinheit gespeichert
sind, bezieht, um den Drehmomentwert des Motors, die Zündungs-Anforderungsspannung
und den Luft-Überschussfaktor auf Grundlage der Drehzahl des Motors, des Öffnungsgrads
des Brennstoff-Einstellventils, des Öffnungsgrads der Drossel, die bei dem Klimatisierungsvorgang
gemessen wurden, zu spezifizieren, den spezifizierten Wert mit einem vorgegebenen
Einstellwert zu vergleichen und auf Grundlage des Vergleichsergebnisses zu beurteilen,
ob der Motor (10) in einem Überlastzustand ist.
11. Verfahren nach einem der Ansprüche 8 bis 10, wobei:
der Speicherschritt ausgebildet ist, um eine Berechnungsgleichung zur Berechnung des
Drehmomentwerts des Motors, der Zündungs-Anforderungsspannung und des Luft-Überschussfaktors
auf Grundlage der Drehzahl des Motors, des Öffnungsgrads des Brennstoff-Einstellventils
und des Öffnungsgrads der Drossel, die bei dem Klimatisierungsvorgang gemessen wurden,
zu speichern und der Beurteilungsschritt den Drehmomentwert des Motors, die Zündungs-Anforderungsspannung
und den Luft-Überschussfaktor auf Grundlage der Informationen, die so erhalten wurden,
durch Verwendung der Berechnungsgleichung, die in der Speichereinheit gespeichert
ist, zu spezifizieren, den spezifizierten Wert mit einem vorgegebenen Einstellwert
zu vergleichen und auf Grundlage des Vergleichsergebnisses zu beurteilen, ob der Motor
(10) in einem Überlastzustand ist.
12. Verfahren nach Anspruch 8, wobei die Klimaanlage ferner eine Umgehungsleitung aufweist,
die zwischen einer Kühlmittel-Hochdruckseite und einer Kühlmittel-Niederdruckseite
bezüglich des Kompressors angeordnet ist, um einen Teil des Kühlmittels an der Kühlmittel-Hochdruckseite
des Kompressors zu der Kühlmittel-Niederdruckseite des Kompressors zurückzuführen,
und ein Umgehungsventil, das in der Umgehungsleitung angeordnet ist, um den zurückzuführenden
Anteil des Kühlmittels einzustellen, wobei, wenn beurteilt wird, dass der Motor in
einem Überlastzustand ist, mindestens eines der Einstellung des Expansionsventils
entsprechend einer Wärmetauscherfunktion als einer von dem Außen-Wärmetauscher und
dem Innen-Wärmetauscher, eine Einstellung der Drehgeschwindigkeit des Gebläses entsprechend
dem anderen Wärmetauscher von dem Außen-Wärmetauscher und dem Innen-Wärmetauscher,
der als Kondensor funktioniert, eine Einstellung der Drehzahl des Motors und eine
Einstellung des Öffnungsgrades des Umgehungsventils in der Umgehungsleitung, die zwischen
der Kühlmittel-Hochdruckseite und der Kühlmittel-Niederdruckseite vorgesehen ist.
13. Verfahren nach Anspruch 12 mit ferner einem Schritt, in Übereinstimmung mit der Klimatisierungslast,
der Änderung von mindestens einem aus dem unteren Grenzwert des Öffnungsgrades des
Expansionsventils entsprechend dem Wärmetauscher, der als Verdampfer funktioniert,
wenn der betreffende Öffnungsgrad, eingestellt wird, dem oberen Grenzwert der Drehgeschwindigkeit
des Gebläses entsprechend dem Wärmetauscher, der als der Kondensor dient, wenn die
betreffende Drehgeschwindigkeit eingestellt wird, dem unteren Grenzwert der Drehzahl
des Motors, wenn die Drehzahl des Motors eingestellt wird, und dem oberen Grenzwert
des Öffnungsgrades des Umgehungsventils, wenn der betreffende Öffnungsgrad, eingestellt
wird.
1. Climatiseur du type à entraînement par un moteur à combustion interne (100) qui est
équipé d'un compresseur (11) entraîné par un moteur à combustion interne (10), d'une
unité extérieure (1) comportant un échangeur de chaleur extérieur (13), un détendeur
extérieur (14) et un ventilateur extérieur (16), et d'une unité intérieure (2a, 2b)
comportant un échangeur de chaleur intérieur (20a, 20b), un détendeur intérieur (21a,
21b) et un ventilateur intérieur (22a, 22b), et qui commande de manière variable un
nombre de tours du moteur à combustion interne conformément à une charge de climatisation
et un fluide frigorigène en circulation déchargé du compresseur entre l'échangeur
de chaleur extérieur et l'échangeur de chaleur intérieur pour, de ce fait, effectuer
une opération de climatisation,
caractérisé en ce qu'il comprend :
une unité de mémorisation (42) configurée pour mémoriser une valeur de couple du moteur
à combustion interne, le nombre de tours du moteur à combustion interne, un degré
d'ouverture d'une soupape d'ajustement de carburant, un degré d'ouverture d'un papillon,
une tension de demande d'allumage et un facteur d'air en excès en association les
uns avec les autres ;
un dispositif de commande (4) comprenant une unité de jugement configurée pour mesurer
le nombre de tours du moteur à combustion interne, le degré d'ouverture de la soupape
d'ajustement de carburant et le degré d'ouverture du papillon pendant l'opération
de climatisation, pour obtenir des informations concernant la valeur de couple du
moteur à combustion interne, la tension de demande d'allumage et le facteur d'air
en excès sur la base des informations qui sont mémorisées dans l'unité de mémorisation
et qui sont mesurées pendant l'opération de climatisation et pour juger, sur la base
des informations obtenues, si le moteur à combustion interne est dans un état de surcharge
ou non ; et
une unité de commande configurée pour effectuer une commande de réduction de charge
de moteur à combustion interne pour réduire la charge du moteur à combustion interne
s'il est jugé par l'unité de jugement que le moteur à combustion interne est dans
un état de surcharge.
2. Climatiseur du type à entraînement par un moteur à combustion interne (100) selon
la revendication 1, dans lequel l'unité de mémorisation (42) est configurée pour mémoriser
la valeur de couple du moteur à combustion interne, le nombre de tours du moteur à
combustion interne, le degré d'ouverture de la soupape d'ajustement de carburant,
le degré d'ouverture du papillon, la tension de demande d'allumage et le facteur d'air
en excès obtenus par une mesure alors qu'un couple prédéterminé est appliqué en tant
que charge au moteur à combustion interne, et le degré d'ouverture de soupape d'ajustement
de carburant et le degré d'ouverture de papillon sont ajustés de sorte que le moteur
à combustion interne soit mis en rotation à un nombre de tours prédéterminé.
3. Climatiseur du type à entraînement par un moteur à combustion interne (100) selon
la revendication 2, dans lequel :
l'unité de mémorisation (42) est configurée pour mapper la valeur de couple du moteur
à combustion interne, le nombre de tours du moteur à combustion interne, le degré
d'ouverture de la soupape d'ajustement de carburant, le degré d'ouverture du papillon,
la tension de demande d'allumage et le facteur d'air en excès obtenus par de multiples
mesures en modifiant le couple appliqué au moteur à combustion interne et le nombre
de tours du moteur à combustion interne, et pour mémoriser un résultat de mappage
; et
l'unité de jugement se réfère aux informations mémorisées dans l'unité de mémorisation
pour spécifier la valeur de couple du moteur à combustion interne, la tension de demande
d'allumage et le facteur d'air en excès sur la base du nombre de tours du moteur à
combustion interne, du degré d'ouverture de la soupape d'ajustement de carburant,
du degré d'ouverture du papillon mesurés pendant l'opération de climatisation, compare
la valeur spécifiée avec une valeur de réglage prédéterminée et juge, sur la base
du résultat de comparaison, si le moteur à combustion interne (10) est dans un état
de surcharge.
4. Climatiseur du type à entraînement par un moteur à combustion interne (100) selon
l'une quelconque des revendications 1 à 3, dans lequel :
l'unité de mémorisation (42) est configurée pour mémoriser une équation de calcul
pour calculer la valeur de couple du moteur à combustion interne, la tension de demande
d'allumage et le facteur d'air en excès sur la base du nombre de tours du moteur à
combustion interne, du degré d'ouverture de la soupape d'ajustement de carburant et
du degré d'ouverture du papillon mesurés pendant l'opération de climatisation ; et
l'unité de jugement spécifie la valeur de couple du moteur à combustion interne, la
tension de demande d'allumage et le facteur d'air en excès sur la base des informations
ainsi obtenues en utilisant l'équation de calcul mémorisée dans l'unité de mémorisation,
compare la valeur spécifiée avec une valeur de réglage prédéterminée et juge, sur
la base du résultat de comparaison, si le moteur à combustion interne (10) est dans
un état de surcharge.
5. Climatiseur du type à entraînement par un moteur à combustion interne selon la revendication
1, comprenant en outre un tuyau de dérivation (17) relié entre un côté haute pression
de fluide frigorigène et un côté basse pression de fluide frigorigène par rapport
au compresseur (11) pour renvoyer une partie du fluide frigorigène du côté haute pression
de fluide frigorigène du compresseur (11) vers le côté basse pression de fluide frigorigène
du compresseur, et une soupape de dérivation (18) disposée dans le tuyau de dérivation
pour ajuster la quantité de fluide frigorigène à renvoyer.
6. Climatiseur du type à entraînement par un moteur à combustion interne selon la revendication
5, dans lequel, lorsqu'il est jugé que le moteur à combustion interne est dans un
état de surcharge, l'unité de commande effectue au moins l'un d'un ajustement du détendeur
(14) correspondant à un échangeur de chaleur fonctionnant en tant qu'évaporateur parmi
l'échangeur de chaleur extérieur et l'échangeur de chaleur intérieur, d'un ajustement
de la vitesse de rotation du ventilateur correspondant à l'autre échangeur de chaleur
fonctionnant en tant que condenseur parmi l'échangeur de chaleur extérieur et l'échangeur
de chaleur intérieur, d'un ajustement du nombre de tours du moteur à combustion interne
(10) et d'un ajustement du degré d'ouverture de la soupape de dérivation dans le tuyau
de dérivation prévu entre le côté haute pression de fluide frigorigène et le côté
basse pression de fluide frigorigène.
7. Climatiseur du type à entraînement par un moteur à combustion interne selon la revendication
5, dans lequel, conformément à la charge de climatisation, l'unité de commande modifie
au moins l'une de la valeur de limite inférieure du degré d'ouverture du détendeur
correspondant à l'échangeur de chaleur fonctionnant en tant qu'évaporateur lorsque
le degré d'ouverture concerné est ajusté, de la valeur de limite supérieure de la
vitesse de rotation du ventilateur correspondant à l'échangeur de chaleur fonctionnant
en tant que condenseur lorsque la vitesse de rotation concernée est ajustée, de la
valeur de limite inférieure du nombre de tours du moteur à combustion interne (10)
lorsque le nombre de tours du moteur à combustion interne est ajusté, et de la valeur
de limite supérieure du degré d'ouverture de la soupape de dérivation lorsque le degré
d'ouverture concerné est ajusté.
8. Procédé de commande d'un climatiseur du type à entraînement par un moteur à combustion
interne (100) qui est équipé d'un compresseur (11) entraîné par un moteur à combustion
interne (10), d'une unité extérieure (1) comportant un échangeur de chaleur extérieur
(13), un détendeur extérieur (14) et un ventilateur extérieur (16) et d'une unité
intérieure (2a, 2b) comportant un échangeur de chaleur intérieur (20a, 20b), un détendeur
intérieur (21a, 21b) et un ventilateur intérieur (22a, 22b), et qui commande de manière
variable un nombre de tours d'un moteur à combustion interne conformément à une charge
de climatisation et un fluide frigorigène en circulation déchargé du compresseur entre
l'échangeur de chaleur extérieur et l'échangeur de chaleur intérieur pour, de ce fait,
effectuer une opération de climatisation,
caractérisé en ce qu'il comprend les étapes :
de mémorisation d'une valeur de couple du moteur à combustion interne, du nombre de
tours du moteur à combustion interne, d'un degré d'ouverture d'une soupape d'ajustement
de carburant, d'un degré d'ouverture d'un papillon, d'une tension de demande d'allumage
et d'un facteur d'air en excès en association les uns avec les autres ;
de mesure du nombre de tours du moteur à combustion interne, du degré d'ouverture
de la soupape d'ajustement de carburant et du degré d'ouverture du papillon pendant
l'opération de climatisation, pour obtenir des informations concernant la valeur de
couple du moteur à combustion interne, la tension de demande d'allumage et le facteur
d'air en excès sur la base des informations qui sont mémorisées dans l'unité de mémorisation
et qui sont mesurées pendant l'opération de climatisation et pour juger, sur la base
des informations obtenues, si le moteur à combustion interne est dans un état de surcharge
ou non ; et
d'exécution d'une commande de réduction de charge de moteur à combustion interne pour
réduire la charge du moteur à combustion interne s'il est jugé par l'unité de jugement
que le moteur à combustion interne est dans un état de surcharge.
9. Procédé selon la revendication 8, dans lequel l'étape de mémorisation est configurée
pour mémoriser la valeur de couple du moteur à combustion interne, le nombre de tours
du moteur à combustion interne, le degré d'ouverture de la soupape d'ajustement de
carburant, le degré d'ouverture du papillon, la tension de demande d'allumage et le
facteur d'air en excès obtenus par une mesure alors qu'un couple prédéterminé est
appliqué en tant que charge au moteur à combustion interne, et le degré d'ouverture
de soupape d'ajustement de carburant et le degré d'ouverture de papillon sont ajustés
de sorte que le moteur à combustion interne soit mis en rotation à un nombre de tours
prédéterminé.
10. Procédé selon la revendication 9, dans lequel :
l'étape de mémorisation est configurée pour mapper la valeur de couple du moteur à
combustion interne, le nombre de tours du moteur à combustion interne, le degré d'ouverture
de la soupape d'ajustement de carburant, le degré d'ouverture du papillon, la tension
de demande d'allumage et le facteur d'air en excès obtenus par de multiples mesures
en modifiant le couple appliqué au moteur à combustion interne et le nombre de tours
du moteur à combustion interne, et pour mémoriser un résultat de mappage ; et
l'étape de jugement se réfère aux informations mémorisées dans l'unité de mémorisation
pour spécifier la valeur de couple du moteur à combustion interne, la tension de demande
d'allumage et le facteur d'air en excès sur la base du nombre de tours du moteur à
combustion interne, du degré d'ouverture de la soupape d'ajustement de carburant,
du degré d'ouverture du papillon mesurés pendant l'opération de climatisation, compare
la valeur spécifiée avec une valeur de réglage prédéterminée et juge, sur la base
du résultat de comparaison, si le moteur à combustion interne (10) est dans un état
de surcharge.
11. Procédé selon l'une quelconque des revendications 8 à 10, dans lequel :
l'étape de mémorisation est configurée pour mémoriser une équation de calcul pour
calculer la valeur de couple du moteur à combustion interne, la tension de demande
d'allumage et le facteur d'air en excès sur la base du nombre de tours du moteur à
combustion interne, du degré d'ouverture de la soupape d'ajustement de carburant et
du degré d'ouverture du papillon mesurés pendant l'opération de climatisation ; et
l'étape de jugement spécifie la valeur de couple du moteur à combustion interne, la
tension de demande d'allumage et le facteur d'air en excès sur la base des informations
ainsi obtenues en utilisant l'équation de calcul mémorisée dans l'unité de mémorisation,
compare la valeur spécifiée avec une valeur de réglage prédéterminée et juge, sur
la base du résultat de comparaison, si le moteur à combustion interne (10) est dans
un état de surcharge.
12. Procédé selon la revendication 8, dans lequel le climatiseur comprend en outre un
tuyau de dérivation relié entre un côté haute pression de fluide frigorigène et un
côté basse pression de fluide frigorigène par rapport au compresseur pour renvoyer
une partie du fluide frigorigène du côté haute pression de fluide frigorigène du compresseur
vers le côté basse pression de fluide frigorigène du compresseur, et une soupape de
dérivation disposée dans le tuyau de dérivation pour ajuster la quantité de fluide
frigorigène à renvoyer, et lorsqu'il est jugé que le moteur à combustion interne est
dans un état de surcharge, au moins l'un de l'ajustement du détendeur correspondant
à un échangeur de chaleur fonctionnant en tant qu'évaporateur parmi l'échangeur de
chaleur extérieur et l'échangeur de chaleur intérieur, de l'ajustement de la vitesse
de rotation du ventilateur correspondant à l'autre échangeur de chaleur fonctionnant
en tant que condenseur parmi l'échangeur de chaleur extérieur et l'échangeur de chaleur
intérieur, de l'ajustement du nombre de tours du moteur à combustion interne et de
l'ajustement du degré d'ouverture de la soupape de dérivation dans le tuyau de dérivation
prévu entre le côté haute pression de fluide frigorigène et le côté basse pression
de fluide frigorigène est effectué.
13. Procédé selon la revendication 12, comprenant en outre une étape, conformément à la
charge de climatisation, de modification d'au moins l'une de la valeur de limite inférieure
du degré d'ouverture du détendeur correspondant à l'échangeur de chaleur fonctionnant
en tant qu'évaporateur lorsque le degré d'ouverture concerné est ajusté, de la valeur
de limite supérieure de la vitesse de rotation du ventilateur correspondant à l'échangeur
de chaleur fonctionnant en tant que condenseur lorsque la vitesse de rotation concernée
est ajustée, de la valeur de limite inférieure du nombre de tours du moteur à combustion
interne lorsque le nombre de tours du moteur à combustion interne est ajusté, et de
la valeur de limite supérieure du degré d'ouverture de la soupape de dérivation lorsque
le degré d'ouverture concerné est ajusté.