JP7243488B2 - Apparatus for calculating ignition plug maintenance timing for heat pump engine and method for calculating maintenance timing for ignition plug of heat pump engine - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spark plug maintenance timing calculation device for a heat pump engine and a maintenance timing calculation method for a spark plug of a heat pump engine.

In this technical field, every time the cumulative operating time of an engine heat pump such as a gas-engine driven heat pump (GHP) reaches a predetermined value (eg, 10,000 hours), for example, replenishment of components is performed. and/or maintenance such as replacement is generally performed. However, the rate of deterioration of engine heat pump components varies depending on operating conditions, such as operating conditions (eg, engine speed and load) and environmental conditions (eg, outside air temperature). Also, the direction (acceleration or deceleration) and magnitude of change in the deterioration rate associated with changes in the operating state of the engine heat pump differ depending on the component. Therefore, if it is possible to accurately estimate the degree of deterioration according to the operating state of each component of the engine heat pump, the timing of maintenance of the engine heat pump can be accurately calculated, and the frequency of maintenance can be made more appropriate. It should be possible.

In particular, with regard to engine spark plugs, excessive wear of the electrodes that cause spark discharge causes fluctuations in the engine rotation speed due to, for example, misfires, etc., making it difficult to operate the engine heat pump normally. There is a risk of becoming. In addition, until the wear amount of the electrode exceeds a predetermined threshold, it is difficult for detectable abnormalities to occur, for example, in the operating conditions of the engine. There are many. Therefore, it is extremely important to accurately estimate the degree of deterioration of the spark plugs of the engine.

Therefore, in this technical field, the required voltage of the spark plug is calculated based on the in-cylinder pressure detected by the in-cylinder pressure acquisition means, and the parameter representing the relationship between the required voltage and the wear amount of the electrode and the calculated value of the required voltage are calculated. There has been proposed a technique for accurately detecting the amount of electrode wear based on (see, for example, Patent Document 1). According to this, appropriate control can be executed according to the progress of wear of the electrode of the spark plug.

However, in order to detect the in-cylinder pressure as described above, in-cylinder pressure acquisition means such as an in-cylinder pressure sensor is essential. Equipping an engine with an in-cylinder pressure sensor may lead to problems such as an increase in the number of parts, a complicated configuration, and an increase in cost.

On the other hand, in an engine-type generator having a plurality of engines, an engine in a failure state or a quasi-failure state (a state with a high possibility of failure) is specified based on the operating state data measured for each engine. Techniques have been proposed (see Patent Literature 2, for example). According to this, it is possible to accurately identify an engine in a failure state or a quasi-failure state, and prompt replacement with a spare engine.

However, the above technology replaces an engine that has fallen into a failure state or a near-failure state after the fact. It is premised that the power generation can be continued by the remaining normal engines even in a quasi-failure state.

An engine heat pump generally has one engine as a drive source for the compressor. is difficult to maintain in good working order. In addition, the configuration including a plurality of engines as described above may lead to problems such as an increase in the size of equipment, an increase in the number of parts, a complication of the configuration, and an increase in cost.

JP 2011-157904 A JP 2018-206302 A

As described above, in the technical field, there is a demand for a calculation device and calculation method for the maintenance timing of spark plugs of a heat pump engine that can appropriately set the maintenance timing that accurately corresponds to the degree of deterioration of the spark plugs. ing.

In view of the above problems, as a result of intensive research, the present inventors have found the first data indicating the relationship between the spark plug required voltage and the state quantity group (engine rotation speed and load), the deterioration rate of the spark plug and the state quantity group second data indicating the relationship between is stored in advance, the required voltage is estimated based on the first data from the state quantity group detected from time to time, the state quantity group detected from time to time, the cumulative operating time and The degree of deterioration of the spark plug is calculated from the required voltage based on the second data, and the operating time when the calculated degree of deterioration reaches the upper limit is calculated as the maintenance timing of the spark plug. It has been found that the maintenance timing can be appropriately set to accurately correspond to .

In view of the above, a maintenance timing calculation device for a spark plug of a heat pump engine according to the present invention (hereinafter sometimes referred to as "the device of the present invention") calculates a maintenance timing for a spark plug provided in a heat pump engine. It is a maintenance timing calculation device for a spark plug of a heat pump engine. The heat pump includes at least an engine, at least one compressor, a circulation path, at least a pair of heat exchangers, and a controller. The compressor is driven by the engine. The circulation path is a path for circulating the heat medium from the discharge port of the compressor to the suction port of the compressor. The heat exchanger is interposed in the circulation path. The control unit is configured to control operating states of the engine and/or the compressor.

The device of the present invention includes a time measurement section, a state quantity detection section, a calculation section, and a data storage section. The time measuring unit is configured to measure the accumulated operating time of the engine from the time when the spark plug is attached or replaced to the present time. The state quantity detection unit includes detection means configured to detect a state quantity group, which is a group of a plurality of state quantities including at least the rotation speed and the load of the engine. The calculation unit is configured to calculate the maintenance timing. The data storage unit stores first data and second data. The first data is data indicating the relationship between at least the required voltage, which is the voltage applied to the discharge electrode of the spark plug, and the group of state quantities. On the other hand, the second data is data indicating at least the relationship between the deterioration speed, which is the speed of change in the degree of deterioration of the spark plug, and the state quantity group.

The calculation unit is configured to execute a maintenance timing calculation process, which is a process including first to sixth steps listed below.

1st step: Acquire the cumulative operating time at the present time from the time measuring section.
Second step: acquiring the state quantity group at the current time from the state quantity detection unit.
Third step: Calculate the required voltage based on the first data from the group of state quantities at the current time.
Fourth step: From the operating time, which is the difference between the cumulative operating time at the previous time when the previous maintenance timing was calculated and the cumulative operating time at the present time, the state quantity group, and the required voltage, the second data is obtained. Based on this, the amount of deterioration, which is the amount of change in the degree of deterioration of the spark plug during the calculation period between the previous time point and the current time point, is calculated.
Fifth step: Calculate the deterioration degree at the present time from the deterioration amount and the previous deterioration degree at the previous time.
Sixth step: Based on at least the degree of deterioration at the present time and the cumulative operating time at the present time, the cumulative operating time when the degree of deterioration of the spark plug reaches a predetermined upper limit is determined as the maintenance timing for the spark plug. calculate.

In a preferred aspect, the control section is configured to execute the first control at predetermined intervals. The first control changes the operating conditions of the engine and/or the compressor according to the required circulation amount when the required circulation amount of the heat medium changes, and changes the required circulation amount. If there is no such control, the operation conditions of the engine and/or the compressor are not changed.

In this case, the computing unit changes the operating conditions of the engine and/or the compressor in the first control at least when the operating conditions of the engine and/or the compressor are changed in the first control. The maintenance timing calculation process is not executed until the first period, which is a period having a predetermined length, elapses from the point in time when the maintenance timing calculation process is performed.

Furthermore, as described at the beginning of this specification, the present invention provides a maintenance timing calculation method for a spark plug of a heat pump engine (hereinafter referred to as "method of the present invention") that is executed by the above-described device of the present invention. There is.) is also related. The details of the method of the invention are apparent from the above description of the device of the invention and will not be repeated here.

According to the device of the present invention, there is provided a calculation device and calculation method for the maintenance timing of the ignition plug of the engine heat pump engine, which can appropriately set the maintenance timing corresponding to the degree of deterioration of the ignition plug of the engine heat pump engine. can do.

Other objects, features and attendant advantages of the present invention will be readily understood from the description of each embodiment of the present invention described with reference to the following drawings.

FIG. 1 is a schematic diagram showing an example of a configuration of a heat pump in which a maintenance timing for an engine spark plug is calculated by a calculation unit included in a spark plug maintenance timing calculation device (first device) for a heat pump engine according to a first embodiment of the present invention; is. FIG. 2 is a schematic diagram showing a configuration of a plurality of compressors used in the heat pump shown in FIG. 1 and an engine that drives these compressors; It is a typical block diagram showing an example of composition of the 1st device. It is a flowchart which shows an example of the flow of a process in the calculation routine of the maintenance timing performed by the calculating part with which a 1st apparatus is provided. FIG. 4 is a schematic graph showing that deterioration of a spark plug of a heat pump engine progresses (the degree of deterioration increases) as the operation time becomes longer. FIG. FIG. 4 is a schematic graph showing that the higher the rotational speed of the engine, the steeper the slope of the graph representing the increase in the wear amount of the electrode of the spark plug with the increase in operating time; FIG. 4 is a schematic graph showing that the higher the required voltage of the spark plug, the steeper the slope of the graph representing the increase in the wear amount of the electrode of the spark plug with the increase in operating time. 10 is a flow chart showing an example of a flow of processing in a maintenance timing calculation routine executed by a calculation unit included in a spark plug maintenance timing calculation device (second device) for a heat pump engine according to a second embodiment of the present invention. A first control routine executed by a control unit provided in a heat pump in which a maintenance timing for an engine spark plug is calculated by a heat pump engine ignition plug maintenance timing calculation device (third device) according to a third embodiment of the present invention. is a flow chart showing an example of the flow of processing in . It is a flowchart which shows one example of the flow of a process in the calculation routine of the maintenance timing performed by the calculating part with which a 3rd apparatus is provided. FIG. 11 is a flowchart showing another example of the flow of processing in a maintenance timing calculation routine executed by a computing unit provided in the third device; FIG. FIG. 11 is a flowchart showing an example of a flow of a processing routine in deterioration degree correction processing executed by a calculation unit included in a spark plug maintenance timing calculation device (fourth device) for a heat pump engine according to a fourth embodiment of the present invention; FIG.

<<1st Embodiment>>
Hereinafter, a maintenance timing calculation device for a spark plug of a heat pump engine according to a first embodiment of the present invention (hereinafter sometimes referred to as "first device") will be described.

The first device is a maintenance timing calculation device for a spark plug of a heat pump engine, which calculates maintenance timing for a spark plug provided in the heat pump engine. A specific example of maintenance performed on spark plugs is, for example, replacement of spark plugs.

The heat pump includes at least an engine, at least one compressor, a circulation path, at least a pair of heat exchangers, and a controller. The compressor is driven by the engine. The circulation path is a path for circulating the heat medium from the discharge port of the compressor to the suction port of the compressor. The heat exchanger is interposed in the circulation path. The control unit is configured to control operating states of the engine and/or the compressor.

FIG. 1 is a schematic diagram showing an example of the configuration of an engine heat pump in which a maintenance timing for engine spark plugs is calculated by a first device. Although FIG. 1 exemplifies a heat pump used in an air conditioner, the engine heat pump whose component maintenance timing is individually calculated by the first device is not limited to the heat pump used in the air conditioner. , and its configuration is not limited to the configuration illustrated in FIG.

The air conditioner 100 includes an outdoor unit 200 and an indoor unit 300, between which a heat medium is circulated through pipes 330 and 340. That is, the pipes 330 and 340 constitute the "circulation path". The outdoor unit 200 includes three compressors 211 to 213, an oil separator 230, a four-way valve 240, a heat exchanger 250 and an accumulator 260. Although the configuration of the compressors 211 to 213 is not particularly limited, for example, all of the three compressors 211 to 213 are scroll compressors. Meanwhile, the indoor unit 300 includes an electronic expansion valve 310 and a heat exchanger 320 . Furthermore, an indoor temperature sensor 284 is provided to detect the temperature in the room to be air-conditioned. The heat exchanger 250 of the outdoor unit 200 and the heat exchanger 320 of the indoor unit 300 constitute the "pair of heat exchangers".

Further, predetermined points of piping for circulating the heat medium between these components include a buffer 221, strainers 222, 223 and 224, a filter dryer 225, an oil bypass regulating valve 270, and a high pressure switch (SW) 281. , and a high pressure sensor 282 are provided. In addition, the outdoor unit 200 is provided with an outdoor temperature sensor 283 that detects the outdoor temperature.

The heat pump electronic control unit (HP-ECU) 110 detects, for example, the indoor temperature detected by the indoor temperature sensor 284 and the outdoor temperature detected by the outdoor temperature sensor 283. The operation of the compressors 211 to 213 is controlled according to the number of indoor units (the number of indoor units in operation), the installation locations of the indoor units, and/or the operating conditions of the heat pump and/or the environmental conditions. The HP-ECU 110 is, for example, an electronic control unit (ECU) having a microcomputer including a CPU, ROM, RAM, interface, etc. as main components.

Furthermore, the outdoor unit 200 includes a heat medium passage that communicates between the oil separator 230, the discharge side (downstream side), and the intake side (upstream side) of the accumulator 260, and a hot gas bypass valve 290 that shuts off and opens the passage. ,including. When the hot gas bypass valve 290 opens the passage, the heat medium discharged from the compressors 211 to 213 bypasses the heat exchanger 250 and returns to the compressors 211 to 213 . By opening the hot gas bypass valve 290, the amount of work required to circulate the heat medium from the discharge side to the suction side of the compressors 211 to 213 is greatly reduced, and the power of the compressors 211 to 213 is increased. can be lowered.

In addition, the compressors 211-213 each include passages for returning the heat transfer medium from the respective intermediate compression chambers to the suction ports, and capacity solenoid valves 291-293 for blocking and opening the passages. By opening the capacity solenoid valves 291-293, the amount of work downstream from the intermediate compression chambers of the compressors 211-213 can be greatly reduced, and the power of the compressors 211-213 can be reduced.

The flow direction of the heat medium in the air conditioner 100 varies depending on the operation mode of the air conditioner 100 (cooling mode and heating mode). However, the circulation path (discharge side path) from the compressors 211 to 213 to the four-way valve 240 via the oil separator 230 and the circulation path (suction side path) from the four-way valve 240 to the compressors 211 to 213 via the accumulator 260 and the strainer 224 side path), as indicated by the arrows in the figure, the flow direction of the heat medium is always the same regardless of the operation mode of the air conditioner 100 .

During cooling, the heat exchanger 320 of the indoor unit 300 functions as a heat transfer source (low temperature side) by the heat pump, and the heat exchanger 250 of the outdoor unit 200 functions as a heat transfer destination (high temperature side) by the heat pump. . On the other hand, during heating, the heat exchanger 250 of the outdoor unit 200 functions as a heat transfer source (low temperature side) by the heat pump, and the heat exchanger 320 of the indoor unit 300 functions as a heat transfer destination (high temperature side) by the heat pump. Function.

In FIG. 1, an engine 400 that drives the compressors 211 to 213 and an engine electronic control unit (ENG-ECU) 410 that controls the operation of the engine 400 are omitted. Therefore, these will be described below with reference to FIG.

The specific configuration of engine 400, such as the number of cylinders, cylinder layout, ignition method, and fuel, is not particularly limited. The engine 400 illustrated in FIG. 1 is a multi-cylinder (in-line four-cylinder in this example), four-cycle, reciprocating piston, spark ignition gas engine.

As described above, the HP-ECU 110 detects, for example, the indoor temperature detected by the indoor temperature sensor 284, the outdoor temperature detected by the outdoor temperature sensor 283, and the number of operating indoor units 300. The operation of the compressors 211 to 213 is controlled according to (the number of operating indoor units 300) and the installation location of the indoor units 300, the operating status of the heat pump, and/or the environmental conditions.

Note that the heat pump used by the air conditioner 100 includes a plurality of compressors 211 to 213, and in at least some of the plurality of compressors 211 to 213, heat is supplied from the engine 400 to the compressor. and a transmission state in which the driving force is transmitted from the engine 400 to the compressor, and a cutoff state in which the driving force is not transmitted from the engine 400 to the compressor.

Specifically, as shown in FIG. 2, three compressors 211 to 213 are belt-driven by an engine 400 . The two compressors 211 and 212 out of the compressors 211 to 213 are always in the transmission state, and only the compressor 213 is configured to be able to switch between the transmission state and the cut-off state by means of a clutch (not shown). there is Thereby, the HP-ECU 110 can switch between operating all of the compressors 211 to 213 or operating only the compressors 211 and 212 according to the operating state of the heat pump and/or the environmental conditions.

The ENG-ECU 410 is an electronic control unit (ECU) having a microcomputer including, for example, a CPU, a ROM, a RAM, an interface, etc., as a main component. The ENG-ECU 410 receives detection signals from various sensors that detect various parameters related to the operating state of the engine 400, and transmits instruction signals for operating the engine 400 and the compressors 211 to 213 to various actuators. controls the operation of the engine 400 according to the amount of work required of the compressors 211-213.

As described above, the HP-ECU 110 and the ENG-ECU 410 constitute the "control section" of the engine heat pump in which the maintenance timings of the components are individually calculated by the first device. However, the configuration of the control unit is not limited to the above, and each ECU may be configured to perform any of the various controls described above. Also, the function as the control section may be achieved in a distributed manner by a plurality of ECUs as described above, or all functions may be achieved by one ECU.

FIG. 3 is a schematic block diagram showing an example of the configuration of the first device. A first device 500 illustrated in FIG. 3 includes a time measurement unit 510, a state quantity detection unit 520, a calculation unit 530, and a data storage unit 540. The time measurement unit 510 is configured to measure the cumulative operating time of the engine 400 in the period from the installation or replacement of the spark plug to the present time. Specifically, the time measurement unit 510 can acquire the operating time of the engine from, for example, the control unit (that is, the HP-ECU 110 and/or the ENG-ECU 410).

The state quantity detection unit 520 includes detection means configured to detect a state quantity group, which is a group of a plurality of state quantities including at least the rotational speed and load of the engine. Specifically, the rotational speed of the engine is determined, for example, based on a signal (actually the time between adjacent pulse signals) from a crank position sensor (not shown) provided in the cylinder block of engine 400. can be detected. Further, the load of engine 400 can be detected, for example, based on the degree of opening of a throttle valve (not shown) interposed in the intake pipe of engine 400 . In this case, the detection means for detecting the load of the engine 400 is, for example, a throttle position sensor (not shown). Alternatively, the load of engine 400 can be detected based on, for example, the pressure difference between the discharge side and the suction side of compressors 211 and 212 . In this case, the detection means for detecting the load of the engine 400 is, for example, pressure sensors (not shown) disposed on the discharge side and the suction side of the compressors 211 and 212 .

The calculation unit 530 is configured to calculate the maintenance timing described above. The calculation unit 530 is also an electronic control unit (ECU) having a microcomputer including, for example, a CPU, a ROM, a RAM, and an interface as main components. In the calculation unit 530, a program corresponding to an algorithm for causing the CPU to execute various processes included in a maintenance timing calculation routine, which will be described later, is stored in the ROM, and the CPU executes the routine according to the program.

The data storage unit 540 stores first data and second data. The first data is data indicating the relationship between at least the required voltage, which is the voltage applied to the discharge electrode of the spark plug, and the group of state quantities. As is well known to those skilled in the art, the required voltage is the voltage applied between the electrodes of the spark plug required to generate spark discharge between the electrodes, and the pressure in the combustion chamber of the engine (i.e. , in-cylinder pressure), the higher the required voltage. The first data is data indicating the relationship between the requested voltage and the group of state quantities (that is, at least the rotational speed and load of engine 400). Therefore, as will be described later in detail, the requested voltage of the spark plug at that point in time can be specified from the group of state quantities at that point in time based on this first data.

The first data as described above can be obtained, for example, by previously conducting an experiment to specify the relationship between the required voltage of the spark plug and various operating conditions. More specifically, for example, the first data can be obtained by conducting an experiment in advance to measure the required voltage of the spark plugs in various combinations of the rotation speed of the engine 400 and the load.

On the other hand, the second data is data indicating at least the relationship between the deterioration speed, which is the speed of change in the degree of deterioration of the spark plug, and the state quantity group. The "deterioration degree" is a value that indicates a state that serves as an index in determining whether maintenance of the spark plug is necessary. Specifically, for example, the degree of wear and/or contamination of the electrode of the spark plug can be used as the degree of deterioration. The "deterioration rate" is the amount of change (increment) in the degree of deterioration per unit time. The second data is data indicating the correspondence relationship between various combinations of the state quantities forming the group of state quantities and the degradation rate of the spark plug. Therefore, as will be described later in detail, it is possible to specify the degradation rate of the spark plug at that point in time based on this second data from the group of state quantities at that time.

The second data as described above can be obtained, for example, by conducting an experiment in advance to identify the relationship between the operating time and the degree of deterioration of the component in various operating states. More specifically, for example, the second data can be obtained by conducting an experiment in advance to observe changes in the degree of deterioration with the lapse of operating time in various combinations of the rotational speed and load of the engine 400. .

In addition to the rotation speed and load of the engine 400, the state quantity group can include other state quantities that affect the spark plug required voltage and/or the deterioration rate. Specific examples of such state quantities include, for example, the degree of deterioration of the spark plugs at each point in time and the cumulative operating time of the engine 400 .

The data storage unit 540 is a storage device such as ROM and/or RAM, and the first data and the second data are stored in the data storage unit 540 as electronic data. Also, the first data and the second data can be stored in the data storage unit 540 as a data table (map) representing the relationship described above or as a function representing the relationship.

In the process of calculating the maintenance time, which will be described later in detail, the CPU that constitutes the calculation unit 530, for example, refers to the first data as a data table, or calculates each state quantity that constitutes the state quantity group in the first data as a function. is input as a variable, the required voltage of the spark plug can be specified or calculated. Similarly, in the process of calculating the maintenance time, which will be described later in detail, the CPU that constitutes the computing unit 530, for example, refers to the second data as a data table, or configures the state quantity group in the second data as a function. By inputting each state quantity as a variable, the degradation rate of the spark plug can be specified or calculated.

The calculation unit is configured to execute a maintenance timing calculation process, which is a process including first to sixth steps listed below.

1st step: Acquire the cumulative operating time at the present time from the time measuring section.
Second step: acquiring the state quantity group at the current time from the state quantity detection unit.
Third step: Calculate the required voltage based on the first data from the group of state quantities at the current time.
Fourth step: From the operating time, which is the difference between the cumulative operating time at the previous time when the previous maintenance timing was calculated and the cumulative operating time at the present time, the state quantity group, and the required voltage, the second data is obtained. Based on this, the amount of deterioration, which is the amount of change in the degree of deterioration of the spark plug during the calculation period between the previous time point and the current time point, is calculated.
Fifth step: Calculate the deterioration degree at the present time from the deterioration amount and the previous deterioration degree at the previous time.
Sixth step: Based on at least the degree of deterioration at the present time and the cumulative operating time at the present time, the cumulative operating time when the degree of deterioration of the spark plug reaches a predetermined upper limit is determined as the maintenance timing for the spark plug. calculate.

FIG. 4 is a flow chart showing an example of the flow of processing in a maintenance timing calculation routine executed by the calculation unit 530 included in the first device 500 . This routine will be described in detail below with reference to FIG. Note that the routine is executed at a predetermined short cycle by the CPU that constitutes the calculation unit 530 .

When the routine is started, the CPU executes the above-described first step in step S110. Specifically, the current cumulative driving time T _(n) is obtained from the driving time measuring unit 510 . The cumulative operating time T _(n) is, as described above, the cumulative operating time (cumulative operating time) of the engine 400 in the period from when the spark plug is attached or replaced to the present time. As described above, the operating time measurement unit 510 measures cumulative operation from the control unit (the HP-ECU 110 and/or the ENG-ECU 410) that controls the operating states of the engine 400 and/or the compressors 211 to 213 that constitute the heat pump. Data regarding time _(n) can be obtained.

By the way, basically, deterioration of the spark plug of the heat pump engine progresses (that is, the degree of deterioration increases) as the operation time becomes longer, as represented by the graph shown in FIG. 5, for example. However, the deterioration speed of the spark plugs changes according to the operating conditions of engine 400 (for example, the rotation speed and load of engine 400, etc.).

More specifically, for example, as the rotation speed of the engine increases, the number of ignitions per operating time increases, so the deterioration rate of the spark plugs increases. Therefore, as represented by the graph shown in FIG. 6, for example, as the engine rotation speed NE increases, the slope of the graph representing the increase in the wear amount of the spark plug electrode with the increase in the operating time increases (NE1 <NE2<NE3). Also, for example, the higher the required voltage of the spark plug, the faster the spark plug deteriorates. Therefore, for example, as represented by the graph shown in FIG. 7, the higher the required voltage V of the spark plug, the greater the slope of the graph representing the increase in the wear amount of the spark plug electrode with the increase in operating time ( V1<V2<V3).

Therefore, the CPU proceeds to the next step S120 and executes the above-described second step. Specifically, state quantities (a group of state quantities) corresponding to operating conditions (for example, the rotational speed and load of the engine 400) that affect the degree of deterioration of the spark plug are obtained from the detection unit 520. do.

As described above, the state quantities forming the group of state quantities are not limited to the rotational speed and load of engine 400 . For example, depending on the accuracy required for the calculated maintenance timing, other state quantities that affect the degree of deterioration of the spark plugs (for example, the degree of deterioration of the spark plugs from time to time, the cumulative operating time of the engine, etc.) may be added to the quantity group. The state quantities constituting the state quantity group may be state quantities that directly affect the degree of deterioration of the spark plug, or state quantities that indirectly affect the degree of deterioration of the spark plug. Alternatively, it may be another state quantity having a correlation with the state quantity that affects the degree of deterioration of the spark plug.

Note that the execution order of the above-described first step and second step (that is, steps S110 and S120) does not necessarily have to be as described above, and the first step may be executed after the second step is executed, or You may perform a 1st step and a 2nd step simultaneously. The CPU proceeds to the next step S130, executes the above-described third step, and specifies or calculates the required voltage V _(n) of the spark plug. Specifically, as described above, the requested voltage V _(n) of the spark plug is specified or calculated from the group of state quantities at the present time based on the first data.

Then, the CPU proceeds to the next step S140, executes the above-described fourth step, and calculates the cumulative operation time T _(n−1) at the time before the calculation of the previous maintenance timing and the current time. From the operation time ΔT (=T ( _{n )} −T _(n−1) ), which is the difference from the cumulative operation time T (n), the required voltage V _(n) , and the state quantity group, the second data Based on this, the amount of deterioration ΔD _(n) , which is the amount of change in the degree of deterioration of the spark plug during the calculation period between the previous point in time and the present point in time, is calculated.

The difference ΔT (=T _(n) −T _(n−1) ) between the cumulative operating time T _(n−1) at the previous time and the cumulative operating time T _(n ) at the present time is the operating time of the engine 400 during the calculation period. (operating hours). As described above, the longer the operation time is, the more the ignition plug deteriorates (that is, the amount of deterioration increases). Further, the degradation rate of the spark plugs at this time varies depending on the rotational speed NE of the engine 400 and the required voltage V of the spark plugs. Therefore, in the fourth step, for example, from the rotational speed NE of the engine 400 at the present time and the required voltage V of the spark plugs, the degradation rate of the spark plugs at the present time is specified or calculated based on the second data described above, and calculated. A deterioration amount ΔD _(n) of the spark plug during the calculation period is calculated from the operating time ΔT and the deterioration rate of the spark plug during the period.

Next, the CPU proceeds to the next step S150 and executes the fifth step. Specifically, the CPU determines the current deterioration of the spark plug based on the deterioration degree D _(n−1) at the previous time and the deterioration amount ΔD _(n) specified or calculated in the fourth step (step S140). Calculate the degree D _(n) .

As described above, the CPU that constitutes the calculation unit 530 executes the routine at predetermined short intervals. Therefore, each time the routine is executed, the current deterioration degree D can be calculated and stored in the data storage unit 540 . On the other hand, in the fourth step described above, the amount of deterioration ΔD _(n) of the spark plugs during the calculation period is calculated. The CPU can calculate the current deterioration degree D _{(n) based on the deterioration degree D (n-1)} at the previous time and the deterioration amount ΔD ( _{n )} during the calculation period. Typically, the degree of deterioration D _(n) at the present time is obtained, for example, from the degree of deterioration D _(n−1) at the previous time and the amount of deterioration ΔD _(n) calculated in the fourth step, using the following formula (1 ) can be calculated by

Next, the CPU proceeds to the next step S160 and executes the sixth step. Specifically, the CPU determines, from at least the deterioration degree D _(n) and the cumulative operating time T _(n) at the present time, the cumulative operating time T when the deterioration degree D reaches a predetermined upper limit value. Calculate as time.

The "upper limit value" is a value corresponding to the degree of deterioration for which maintenance should be performed as described above. It is the value corresponding to the maximum value. A specific value of the upper limit can be appropriately determined, for example, by conducting an experiment in advance to measure the degree of deterioration of the spark plug when the heat pump engine becomes unable to operate normally.

Further, a specific method for calculating the cumulative operating time T when the deterioration degree D reaches a predetermined upper limit value from at least the current deterioration degree D _(n) and the cumulative operating time T _(n) is not particularly limited. However, for example, depending on the accuracy required for the finally calculated maintenance timing, the processing capacity of the CPU that constitutes the calculation unit 530, the capacity and data transfer speed of the data storage unit 540, etc. It can be appropriately selected from various methods.

For example, maintenance can be performed by linear interpolation based on the current (that is, the latest) deterioration degree D _(n) , the cumulative operating time T _(n) , and the origin (the deterioration degree D ₍₀₎ = 0 at the cumulative operating time T = 0). time can be calculated. Alternatively, a plurality of degrees _of deterioration (D _(n) , D _(n-1) , D _{(n-2 ) . 1)} , T _(n−2) . Furthermore, the pattern of transition of the degree of deterioration D of the spark plug with an increase in the accumulated operating time T is obtained by, for example, prior experiments, and at least the degree of deterioration D _(n) and the accumulated operating time T _(n) at the present time are determined. The maintenance time may be calculated by applying to the pattern.

The ignition plug maintenance timing calculated as described above can be confirmed by, for example, a person in charge of maintenance by connecting a measuring device or a diagnostic device to a connector or the like provided in the first device. Alternatively, for example, the maintenance time may be displayed by a display device such as a liquid crystal display provided in the first device. Furthermore, the maintenance time calculated as described above may be automatically transmitted to a server used by a maintenance company, for example, via a network such as the Internet and/or a telephone network.

As described above, according to the first device, the first data indicating the relationship between the required voltage of the spark plug and the group of state quantities (for example, the rotation speed and load of the engine) is stored in advance. The required voltage can be estimated based on the first data from the group of state quantities detected at . Therefore, there is no need to provide an expensive in-cylinder pressure sensor or other in-cylinder pressure acquisition means to detect the in-cylinder pressure, as in the above-described prior art, and problems such as an increase in the number of parts, a complicated configuration, and an increase in cost are required. can be avoided.

Further, according to the first device, the second data indicating the relationship between the deterioration rate of the spark plug and the state quantity group is stored in advance, and the state quantity group and the accumulated operating time detected from time to time, and the above-mentioned The degree of deterioration of the spark plug can be accurately calculated based on the second data from the required voltage estimated in this manner. Furthermore, by calculating the operation time when the degree of deterioration calculated in this manner reaches the upper limit value as the maintenance timing of the spark plug, the maintenance timing that accurately corresponds to the degree of deterioration of the spark plug can be appropriately set. be able to.

<<Second embodiment>>
A maintenance timing calculation device for a spark plug of a heat pump engine (hereinafter sometimes referred to as a "second device") according to a second embodiment of the present invention will be described below.

As described above, in the first device, the first data indicating the relationship between the required voltage of the spark plug and the group of state quantities (at least the rotational speed and load of the engine) is stored in advance, and is detected from time to time. The required voltage can be estimated based on the first data from the state quantity group. Then, the second data indicating the relationship between the deterioration rate of the spark plug and the state quantity group is stored in advance, and the state quantity group and the accumulated operating time detected from time to time, and the required voltage estimated as described above. Therefore, the degree of deterioration of the spark plug can be accurately calculated based on the second data.

However, for example, the operating conditions (for example, engine speed, load, etc.) may change due to, for example, changes in the conditions set by the user of the heat pump, changes in temperature due to natural phenomena, and the like. Alternatively, the operating conditions may change suddenly due to some sudden disturbance. Calculating the maintenance timing based on the state quantity group acquired in such a transitional state in the change of the operating state may lead to problems such as deterioration of accuracy of the maintenance timing, for example.

Therefore, the second device is the above-described first device, and the computing unit performs the maintenance timing calculation process only in a state in which the variation width of the state quantity constituting the state quantity group is less than the predetermined first threshold value. is a maintenance timing calculation device for a spark plug of a heat pump engine.

The "first threshold" is, for example, a state assumed in a steady state, not a transient state in a change in operating state caused by a change in condition settings, natural phenomena and/or sudden disturbances as described above It can be appropriately determined according to the fluctuation range of each state quantity that constitutes the quantity group. The calculation unit included in the second device does not execute the maintenance timing calculation process in a state where the fluctuation range of each state quantity is equal to or greater than the first threshold, and only in a state where the fluctuation range of each state quantity is less than the first threshold. Execute maintenance timing calculation processing.

FIG. 8 is a flow chart showing an example of the flow of processing in a maintenance timing calculation routine executed by the calculation unit 530 provided in the second device. This routine will be described in detail below with reference to FIG. Note that the routine is executed at a predetermined short cycle by the CPU that constitutes the calculation unit 530 .

When the routine is started, the CPU determines in step S100 whether or not the variation width of each state quantity constituting the state quantity group is less than a predetermined first threshold. Specifically, the CPU acquires each state quantity forming the state quantity group from the detection unit 520, and determines whether or not the fluctuation range of each state quantity in a predetermined period is smaller than the first threshold. The length of the "predetermined period" is, for example, in a transient state in which the operating state of the engine is in a transitional state due to changes in the operating state caused by changes in the condition settings, natural phenomena and/or sudden disturbances as described above. It is determined to be long enough to determine whether or not it is in a steady state. The specific length of the predetermined period is, for example, the fluctuation width of each state quantity when the engine is in a transient state and the fluctuation width of each state quantity when the engine is in a steady state. can be determined by conducting an experiment in advance to compare the

When the variation width of each state quantity constituting the state quantity group is less than the first threshold value (that is, when the operating state of the engine is in a steady state), the CPU determines "Yes" in the above step S100, and proceeds to the next step. The process proceeds to step S110. The flow of processing after step S110 is the same as the flow chart shown in FIG. 4 referred to in the description of the first device, so description thereof will be omitted here. On the other hand, if the fluctuation width of each state quantity constituting the state quantity group is equal to or greater than the first threshold value (that is, if the operating state of the engine is in a transitional state), the CPU determines "No" in step S100. and terminate the routine.

As a result of the above, according to the second device, the state obtained in the steady state rather than the transient state in the change in the operating state caused by the change in the condition setting, the natural phenomenon and/or the sudden disturbance as described above A spark plug maintenance timing is calculated based on the quantity group. Therefore, it is possible to effectively reduce problems such as a decrease in accuracy of maintenance timing, for example.

<<Third embodiment>>
A maintenance timing calculation device for a spark plug of a heat pump engine according to a third embodiment of the present invention (hereinafter sometimes referred to as a "third device") will be described below.

As described above, in the second device, the maintenance timing calculation process is executed only in a state where the fluctuation range of the state quantities forming the state quantity group is less than the first threshold. As a result, it is possible to reduce problems such as a decrease in accuracy of the maintenance timing due to the calculation of the maintenance timing based on the state quantity group acquired in the transitional state due to the change in the operating state as described above. can.

By the way, in this technical field, for example, changes in the difference between the temperature in the room to be air-conditioned and the set temperature, changes in the number of indoor units in operation, changes in the condition settings by users, etc. The presence or absence of a change in the required circulation amount of the heat medium) is detected at a predetermined cycle (for example, every 30 seconds), and only when a change in the load is detected, the operating conditions such as the engine rotation speed are changed, There is known an engine heat pump that is controlled to continue steady operation under constant operating conditions without changing the operating conditions when no load fluctuation is detected.

In the heat pump as described above, the timing at which the operating conditions can be changed by the control is determined in advance. Therefore, by not executing the maintenance timing calculation process in the period from when the operating condition is changed by the above control until the operating state becomes a steady state, the state quantity group acquired in the transient state It is possible to more reliably and easily reduce problems such as deterioration in accuracy of the maintenance timing due to calculation of the maintenance timing based on the above.

Therefore, in the third device, the control unit provided in the heat pump is configured to perform the first control at predetermined intervals. "First control" refers to (for example, changes in the difference between the temperature in the room to be air-conditioned and the set temperature, changes in the number of indoor units in operation, changes in the user's condition settings, etc.) If there is a change in the required circulation amount of the heat medium (due to fluctuations, etc.), the operating conditions of the engine and/or compressor are changed according to the required circulation amount, and if there is no change in the required circulation amount, the engine and/or the operation condition of the compressor is not changed.

Furthermore, in the third device, at least when the operating conditions of the engine and/or the compressor are changed in the first control, a predetermined The calculation unit is configured so as not to execute the maintenance timing calculation process until the first period, which is a period having a length, has passed.

The specific length of the "first period" is, for example, the operating conditions of the engine when the required circulation amount of the heat medium in the target heat pump is changed variously and/or each state corresponding to the operating conditions It can be appropriately determined according to the length of time required for the value of the quantity to stabilize. Such a length of time can be measured, for example, by preliminary experiments in which the required circulation amount of the heat medium is variously changed in the target heat pump.

Further, as described above, the computing unit provided in the third device changes the operating conditions of the engine and/or the compressor in the first control at least when the operating conditions of the engine and/or the compressor are changed in the first control. is changed until a predetermined first period elapses, the maintenance timing calculation process is not executed. On the other hand, when the operating conditions of the engine and/or the compressor are not changed in the first control, the maintenance timing calculation process can be executed at predetermined intervals as described in the explanation regarding the first device.

FIG. 9 shows an example of the flow of processing in the first control routine executed by the control unit (HP-ECU 110 and ENG-ECU 410) provided in heat pump 100 in which the maintenance timing of the spark plugs of engine 400 is calculated by the third device. It is a flow chart showing. This routine will be described in detail below with reference to FIG. The routine is executed at a predetermined short period (for example, every 30 seconds) by the CPU that constitutes the control unit provided in the heat pump 100 .

When the routine is started, the CPU determines in step S210 whether or not engine 400 is in operation. If the engine 400 is not in operation (that is, if the engine 400 is stopped), the CPU makes a "No" determination and terminates the routine. On the other hand, if the engine 400 is in operation, the CPU determines "Yes" and proceeds to the next step S220. In step S220, the CPU determines whether or not the required circulation amount of the heat medium in heat pump 100 has changed.

If there is no change in the required circulation amount of the heat medium, the CPU determines "No" and temporarily ends the routine. On the other hand, if the required circulation amount of the heat medium has changed, the CPU determines "Yes" and proceeds to the next step S230. In step S230, the CPU determines, for example, the rotational speed of the engine 400, the number of operating compressors 211 and 212, and/or the opening degrees of the capacity solenoid valves 291 to 293 of the compressors 211 to 213, according to the required circulation amount of the heat medium. For example, an instruction signal for changing the operating state of heat pump 100 is sent. As a result, for example, the rotational speed of engine 400, the number of compressors in operation, and/or the opening degree of a capacity solenoid valve, etc. change, and the operating state of engine 400 temporarily becomes a transitional state. Therefore, the CPU proceeds to the next step S240 and clears the flag FLG indicating that the operating state of the engine 400 is in the steady state (sets the value of the flag FLG to "0 (zero)").

Next, the CPU advances the process to the next step S250, and determines whether or not the first period P1 has passed since the time when the instruction signal was sent (that is, when the operating state of the engine 400 reaches a steady state and each whether or not the variation width of the state quantity is less than a predetermined first threshold value Th1). When the first period P1 has not passed since the instruction signal was sent (that is, the operating state of the engine 400 has not yet reached a steady state, and the variation range of each state quantity is equal to or greater than the first threshold value Th1 case), the CPU determines “No” in step S250, returns the process to before step S250, and waits until the first period P1 elapses. On the other hand, when the first period P1 has passed since the time when the instruction signal was sent (that is, when the operating state of the engine 400 reaches a steady state and the variation range of each state quantity is less than the first threshold value Th1). , the CPU determines "Yes" in step S250, and proceeds to the next step S260.

In the next step S260, the CPU sets a flag FLG (sets the value of the flag FLG to "1") indicating that the operating state of engine 400 is in a steady state, and ends the routine.

As described above, the control unit provided in the heat pump 100 changes the operating conditions of the engine 400 and/or the compressors 211 to 213 in accordance with the required circulation amount of the heat medium when the required circulation amount of the heat medium changes. If there is no change in the required circulation amount of the heat medium, control (first control) that does not change the operating conditions of the engine 400 and/or the compressors 211 to 213 is executed at predetermined intervals. In addition, the control unit provided in heat pump 100 determines whether a first period, which is a period having a predetermined length, has passed since the time when the operating conditions of engine 400 and/or compressors 211 to 213 were changed in the first control. The value of flag FLG indicating whether or not (that is, whether or not the operating state of engine 400 has reached a steady state) is set appropriately.

Therefore, by referring to the value of the flag FLG, the calculation unit provided in the third device calculates a predetermined length from the time when the operating conditions of the engine 400 and/or the compressors 211 to 213 are changed in the first control. The maintenance timing calculation process can be executed only after the first period, which is the period of time, has passed. That is, the calculation unit provided in the third device can calculate the spark plug maintenance timing only when the operating state of the engine 400 is not in a transient state but in a steady state, based on the flag FLG.

FIG. 10 is a flow chart showing an example of the flow of processing in a maintenance timing calculation routine executed by the calculation unit 530 provided in the third device. This routine will be described in detail below with reference to FIG. Note that the routine is executed at a predetermined short cycle by the CPU that constitutes the calculation unit 530 .

When the routine is started, the CPU configuring the calculation unit 530 determines whether or not the value of the flag FLG described above is "1" in step S150. Specifically, the CPU configuring the calculation unit 530 acquires the value of the flag FLG from the control unit of the heat pump 100, and determines whether or not the value of the flag FLG is "1". If the value of flag FLG is not "1" (that is, if the operating state of engine 400 is not in a steady state), the CPU makes a "No" determination in step S150, and terminates the routine. On the other hand, if the value of flag FLG is "1" (that is, if the operating state of engine 400 is in a steady state), the CPU determines "Yes" in step S150, and proceeds to the next step S110. . The flow of processing after step S110 is the same as the flow chart shown in FIG. 4 referred to in the description of the first device, so description thereof will be omitted here.

As described above, in the third device, in the engine heat pump in which the above-described first control is executed, at least when the operating conditions of the engine and/or the compressor are changed in the first control, the engine and/or the maintenance timing calculation process is not executed until the first period, which is a period having a predetermined length, elapses after the operating condition of the compressor is changed. As a result, the state quantity group can be obtained more reliably and easily in the steady state rather than in the transient state in the change of the operating state caused by the load fluctuation, so the state obtained in the transient state It is possible to more reliably and easily reduce problems such as a decrease in accuracy of the maintenance timing due to calculation of the maintenance timing based on the quantity group.

Note that even if the operating conditions of the engine and/or the compressor are not changed in the first control, maintenance is not performed until a predetermined first period elapses from the time when it is confirmed whether or not there is a change in the required circulation amount of the heat medium. The timing calculation process may not be executed. For example, if the first period is sufficiently short with respect to the period for checking whether the required circulation amount of the heat medium has changed, regardless of whether the operating conditions of the engine and/or the compressor are changed by the first control, Even if the maintenance timing calculation process is not executed until the first period elapses after confirming whether or not there is a change in the required circulation amount of the heat medium, acquisition of the state quantity group is not hindered. In addition, since there is no need to change the timing of executing the maintenance timing calculation process depending on whether or not there is a change in the required circulation amount of the heat medium, the routine executed by the CPU of the calculation unit can be simplified.

In the example described with reference to FIGS. 9 and 10, whether or not the maintenance timing calculation process is to be executed depends on the value of the flag FLG which is appropriately set in steps S240 and S260 of the flowchart shown in FIG. is controlled (see step S150 in the flowchart shown in FIG. 10). However, as represented by the flowchart shown in FIG. 11, for example, if the operating conditions of the engine and/or the compressor are changed in at least the first control without using the flag FLG, the engine and/or / Alternatively, the calculation unit may be configured so as not to execute the maintenance timing calculation process until a first period, which is a period having a predetermined length, elapses after the operating condition of the compressor is changed.

<<Fourth embodiment>>
A maintenance timing calculation device for a spark plug of a heat pump engine according to a fourth embodiment of the present invention (hereinafter sometimes referred to as a "fourth device") will be described below.

According to various devices of the present invention including the above-described first device to third device, the required voltage of the spark plug is estimated from the operating state of the engine without providing a cylinder pressure acquisition means such as an expensive cylinder pressure sensor. , the degree of deterioration of the spark plug can be accurately calculated. Furthermore, by calculating the operation time when the degree of deterioration calculated in this manner reaches the upper limit value as the maintenance timing of the spark plug, the maintenance timing that accurately corresponds to the degree of deterioration of the spark plug can be appropriately set. be able to.

However, it is also possible that there may be a discrepancy between the degree of deterioration calculated by the device of the present invention and the actual degree of deterioration due to, for example, variations in the quality of spark plugs during manufacture and/or variations in the degree of deterioration due to use. be done. For example, if the actual degree of deterioration is greater than the degree of deterioration calculated by the device of the present invention, malfunction of the spark plug (for example, misfire of the engine) occurs at an unexpected time, causing the heat pump to operate stably. It may become difficult to operate.

On the other hand, if the deviation between the calculated deterioration degree and the actual deterioration degree as described above is assumed from the beginning and the maintenance timing is calculated early, the maintenance timing that accurately corresponds to the deterioration degree of the spark plug can be calculated. It may become difficult to achieve the purpose of the present invention to set appropriately.

Therefore, the fourth device is a device of the present invention including the above-described first device to third device, wherein the engine rotation when the ignition output of the spark plug is temporarily reduced by a predetermined first amount The calculation unit is configured to execute the deterioration degree correction process when the variation width of the speed is equal to or greater than a predetermined second threshold. The "second threshold value" is a value corresponding to the fluctuation range of the engine rotation speed in a state where the engine rotation speed makes it difficult for the heat pump to operate normally due to the occurrence of a misfire or the like. Such a second threshold can be specified, for example, by conducting an experiment in advance to observe the operating status of the heat pump when the heat pump is operated by an engine equipped with spark plugs having various degrees of deterioration.

Further, the above-mentioned "first amount" is such that, for example, even if the ignition output of a spark plug that does not require maintenance (for example, replacement, etc.) is reduced by the first amount, the fluctuation range of the engine rotation speed is the first. Although not equal to or greater than two thresholds, it is determined such that when the ignition output of the spark plug in the state requiring maintenance is reduced by the first amount, the fluctuation range of the engine rotation speed becomes equal to or greater than the second threshold. Specifically, the first amount is such that, for example, even if the ignition output of a spark plug having a degree of deterioration that has not yet reached the upper limit value described above is reduced by the first amount, the fluctuation range of the engine rotation speed is the second amount. It is determined so that if the ignition output of the spark plug whose degree of deterioration has already reached the upper limit value is reduced by the first amount, the fluctuation range of the engine rotation speed will be equal to or greater than the second threshold value, although it will not be equal to or greater than the threshold value. . The specific magnitude of the first quantity may be a predetermined fixed value, or may be a variable value that is determined to decrease as the degree of deterioration of the spark plug at that time increases. good.

Note that the arithmetic unit included in the fourth device is configured to reduce the ignition output of the spark plug by the first amount by reducing the energization time and/or the applied voltage to the spark plug. Specifically, the arithmetic unit provided in the fourth device, for example, through the control unit (ENG-ECU) provided in the heat pump, shortens the energization time to the electrode for causing spark discharge of the spark plug, or The ignition output of the ignition plug is reduced by a first amount by lowering the voltage applied to the ignition plug.

The deterioration degree correction process is a process for increasing the current deterioration degree of the spark plug by a predetermined second amount. The above-mentioned "second amount" may be, for example, an absolute amount of the degree of deterioration of the spark plug (for example, the amount of wear of the electrode for causing spark discharge). It may be a relative value (ratio). Further, the specific magnitude of the second amount may be a predetermined fixed value, or a variation that is determined to increase as the range of variation in the rotational speed of the engine detected from time to time increases. can be a value.

FIG. 12 is a flowchart showing an example of the flow of a processing routine in the deterioration degree correction processing executed by the computing section 530 provided in the fourth device. This routine will be described in detail below with reference to FIG. Note that this routine is executed at a predetermined short period (for example, every one hundred hours to several hundred hours) by the CPU that constitutes the computing unit 530 .

When the routine is started, in step S310, the CPU sends an instruction signal to the control unit (ENG-ECU 410) of heat pump 100 to reduce the energization time and/or applied voltage to the spark plug. This reduces the ignition output of the spark plugs of engine 400 by the first amount. Next, the CPU advances the process to step S320, and measures the rotation speed NE of engine 400 over a predetermined period.

The length of the "predetermined period" is, for example, the period from when the ignition output of the spark plug in the state requiring maintenance is reduced by the first amount to when the rotational speed NE of the engine 400 fluctuates. It can be determined appropriately according to the length. A specific length of such a period is, for example, a period from when the ignition output of the spark plug in a state requiring maintenance is reduced by the first amount to when fluctuations occur in the rotation speed NE of the engine 400. can be determined by conducting an experiment in advance to measure the length of

Next, the CPU advances the process to step S330 and determines whether or not variation width ΔNE of rotation speed NE of engine 400 is greater than or equal to second threshold value Th1 described above. When the fluctuation range ΔNE of the rotation speed NE of the engine 400 is less than the second threshold value Th1, the difference between the current deterioration degree D _(n) of the spark plug calculated by the above-described maintenance timing calculation process and the actual deterioration degree is can be determined to be sufficiently small. Therefore, the CPU makes a "No" determination in step S330, and terminates the routine without correcting the current deterioration degree D _(n) of the spark plug.

On the other hand, when the fluctuation range ΔNE of the rotation speed NE of the engine 400 is equal to or greater than the second threshold value Th1, the current deterioration degree D _(n) of the spark plug calculated by the maintenance timing calculation process and the actual deterioration degree are It can be judged that the divergence is large. Therefore, the CPU determines "Yes" in step S330, and proceeds to the next step S340.

In step S340, the CPU corrects the current deterioration degree D _(n) of the spark plug. Specifically, the CPU increases the current deterioration degree D _(n) of the spark plug by a predetermined second amount ΔD2.

As described above, in the fourth device, when the fluctuation range of the engine rotation speed when the ignition output of the spark plug is temporarily reduced by the predetermined first amount is equal to or greater than the second threshold, the current ignition The degradation of the plug is increased by a second amount. As a result, for example, due to variations in quality during manufacture of spark plugs and/or variations in deterioration due to use, etc., there may be a deviation between the degree of deterioration calculated by the device of the present invention and the actual degree of deterioration. Also, the deviation can be reduced, and the maintenance timing of the spark plug can be calculated more accurately.

<<Fifth Embodiment>>
A method for calculating maintenance timing for a spark plug of a heat pump engine according to a fifth embodiment of the present invention (hereinafter sometimes referred to as a "fifth method") will be described below.

As described at the beginning of this specification, the present invention provides a maintenance timing calculation method for a spark plug of a heat pump engine (this Inventive method).

Therefore, the fifth method includes at least an engine, at least one compressor driven by the engine, a circulation path that is a passage for circulating the heat medium from the discharge port of the compressor to the suction port of the compressor, and In a heat pump comprising at least one pair of heat exchangers intervening in a path and a control unit configured to control the operating state of an engine and/or a compressor, calculating maintenance timing of spark plugs provided in the engine, A maintenance timing calculation method for a spark plug of a heat pump engine.

A fifth method includes a time measuring unit configured to measure the cumulative operating time of the engine from the time of installation or replacement of the spark plug to the present time, and a plurality of state quantities including at least the rotation speed and load of the engine. a state quantity detection unit including a detection means configured to detect a state quantity group that is a group consisting of; a calculation unit configured to calculate maintenance timing; first data, which is data indicating the relationship between the required voltage, which is the voltage at which the spark plug is required, and the group of state quantities; and a data storage section storing the second data.

Specifically, a maintenance timing calculation process, which is a process including first to sixth steps listed below, is executed by the calculation unit.

1st step: Acquire the cumulative operating time at the present time from the time measuring section.
Second step: acquiring the state quantity group at the current time from the state quantity detection unit.
Third step: Calculate the required voltage based on the first data from the group of state quantities at the current time.
Fourth step: From the operating time, which is the difference between the cumulative operating time at the previous time when the previous maintenance timing was calculated and the cumulative operating time at the present time, the state quantity group, and the required voltage, the second data is obtained. Based on this, the amount of deterioration, which is the amount of change in the degree of deterioration of the spark plug during the calculation period between the previous time point and the current time point, is calculated.
Fifth step: Calculate the deterioration degree at the present time from the deterioration amount and the previous deterioration degree at the previous time.
Sixth step: Based on at least the degree of deterioration at the present time and the cumulative operating time at the present time, the cumulative operating time when the degree of deterioration of the spark plug reaches a predetermined upper limit is determined as the maintenance timing for the spark plug. calculate.

The details of the heat pump, the spark plug maintenance timing calculation device for the heat pump engine, and the first to sixth steps have already been described in the description of the first device, so descriptions thereof are omitted here. do.

According to the fifth method, the first data indicating the relationship between the required voltage of the spark plug and the state quantity group (for example, engine speed and load) is stored in advance, and the state quantity group detected from time to time is stored in advance. , the required voltage can be estimated based on the first data. Therefore, there is no need to provide an expensive in-cylinder pressure sensor or other in-cylinder pressure acquisition means to detect the in-cylinder pressure, as in the above-described prior art, and problems such as an increase in the number of parts, a complicated configuration, and an increase in cost are required. can be avoided.

Further, according to the fifth method, the second data indicating the relationship between the deterioration rate of the spark plug and the state quantity group is stored in advance, and the state quantity group and the accumulated operating time detected from time to time, and the above-mentioned The degree of deterioration of the spark plug can be accurately calculated based on the second data from the required voltage estimated in this way. Furthermore, by calculating the operation time when the degree of deterioration calculated in this manner reaches the upper limit value as the maintenance timing of the spark plug, the maintenance timing that accurately corresponds to the degree of deterioration of the spark plug can be appropriately set. be able to.

<<Sixth embodiment>>
A method for calculating maintenance timing of a spark plug for a heat pump engine according to a sixth embodiment of the present invention (hereinafter sometimes referred to as "sixth method") will be described below.

The sixth method is the above-described fifth method, in which the calculation unit executes the maintenance timing calculation process only in a state where the variation width of the state quantities constituting the state quantity group is less than a predetermined first threshold. A maintenance timing calculation method for a spark plug of a heat pump engine.

As described above, the sixth method is a maintenance timing calculation method for a spark plug of a heat pump engine corresponding to the above-described second device. Therefore, the details of the sixth method have already been described in the description of the second device, and therefore the description thereof will be omitted here.

According to the sixth method, as described in the description of the second device, it is acquired in a steady state rather than a transient state in changes in operating conditions caused by changes in condition settings, natural phenomena and/or sudden disturbances. The ignition plug maintenance timing is calculated based on the group of state quantities obtained. Therefore, it is possible to effectively reduce problems such as a decrease in accuracy of maintenance timing, for example.

<<Seventh embodiment>>
A method for calculating maintenance timing of a spark plug for a heat pump engine according to the seventh embodiment of the present invention (hereinafter sometimes referred to as "seventh method") will be described below.

The seventh method is the above-described fifth method or sixth method, in which the control unit provided in the engine heat pump controls the engine and/or compressor according to the required circulation amount when the required circulation amount of the heat medium changes. change the operating conditions of the compressor and do not change the operating conditions of the engine and/or the compressor if there is no change in the required circulation amount, and perform the first control at predetermined intervals. is configured as

Furthermore, at least when the operating conditions of the engine and/or the compressor are changed in the first control, the computing unit performs the operation for a predetermined length from the time when the operating conditions of the engine and/or the compressor are changed in the first control. The maintenance timing calculation process is not executed until the first period, which is a period having

As described above, the seventh method is a maintenance timing calculation method for a spark plug of a heat pump engine corresponding to the third device described above. Therefore, the details of the seventh method have already been described in the description of the third device, and therefore description thereof will be omitted here.

In the seventh method, in the engine heat pump in which the above-described first control is executed, if the operating conditions of the engine and/or the compressor are changed at least in the first control, the engine and/or the compressor in the first control The maintenance timing calculation process is not executed until the first period, which is a period having a predetermined length, elapses after the operating condition is changed. As a result, the state quantity group can be obtained more reliably and easily in the steady state rather than in the transient state in the change of the operating state caused by the load fluctuation, so the state obtained in the transient state It is possible to more reliably and easily reduce problems such as a decrease in accuracy of the maintenance timing due to calculation of the maintenance timing based on the quantity group.

<<Eighth Embodiment>>
A method for calculating maintenance timing of a spark plug for a heat pump engine according to the eighth embodiment of the present invention (hereinafter sometimes referred to as "eighth method") will be described below.

The eighth method is a method of the present invention including the fifth method to the seventh method described above, wherein the calculation unit reduces the energization time and/or the applied voltage to the spark plug, thereby reducing the ignition output of the spark plug. is temporarily decreased by a predetermined first amount, and if the fluctuation range of the engine rotation speed is equal to or greater than a predetermined second threshold, the current deterioration degree of the spark plug is increased by a predetermined second amount. is a maintenance timing calculation method for a spark plug of a heat pump engine, in which deterioration degree correction processing is executed.

As described above, the eighth method is a maintenance timing calculation method for a spark plug of a heat pump engine corresponding to the fourth device described above. Therefore, the details of the eighth method have already been described in the description of the fourth device, so description thereof will be omitted here.

In the eighth method, if the fluctuation range of the engine rotation speed when the ignition output of the spark plug is temporarily reduced by a predetermined first amount is equal to or greater than the second threshold, the current deterioration degree of the spark plug is Increased by a second amount. As a result, there may be a discrepancy between the degree of deterioration calculated by the method of the present invention and the actual degree of deterioration due to, for example, variations in the quality of spark plugs during manufacture and/or variations in the degree of deterioration due to use. Also, the deviation can be reduced, and the maintenance timing of the spark plug can be calculated more accurately.

Although several embodiments having specific configurations have been described, at times with reference to the accompanying drawings, for the purpose of illustrating the present invention, the scope of the present invention is not limited to these exemplary embodiments. It should not be construed as limiting, and it goes without saying that modifications can be made as appropriate within the scope of the claims and the matters described in the specification.

DESCRIPTION OF SYMBOLS 100... Air conditioning apparatus (including heat pump), 110... Heat pump electronic control unit (HP-ECU), 200... Outdoor unit, 211, 212 and 213... Compressor, 221... Buffer, 222, 223 and 224... Strainer, 225 Filter dryer 230 Oil separator 240 Four-way valve 250 Heat exchanger (outdoor unit) 260 Accumulator 270 Oil bypass control valve 281 High pressure switch (SW) 282 High pressure sensor 283 Outdoor temperature sensor 284 Indoor temperature sensor 290 Hot gas bypass valve 291, 292 and 293 Capacity solenoid valve 300 Indoor unit 310 Electronic expansion valve 320 Heat exchanger (indoor unit) 330 and 340...Piping, 400...Multi-cylinder engine (engine), 410...Engine electronic control unit (ENG-ECU), 500...Maintenance timing calculation device for engine heat pump outdoor unit (first device), 510...Operating time measurement section, 520...detection section, 530...calculation section, and 540...data storage section.

Claims (8)

at least an engine; at least one compressor driven by the engine; a circulation path that is a passage for circulating a heat medium from a discharge port of the compressor to an intake port of the compressor; and a control unit configured to control the operating state of the engine and/or the compressor, in which the maintenance timing of the spark plug provided in the engine is calculated, A maintenance timing calculation device for a spark plug of a heat pump engine,
A time measuring unit configured to measure the cumulative operating time of the engine from the time of installation or replacement of the spark plug to the present time, and a plurality of state quantities including at least the rotational speed and load of the engine. A state quantity detection unit including detection means configured to detect a group of state quantities, a calculation unit configured to calculate the maintenance timing, and a voltage applied to at least the discharge electrode of the spark plug. First data, which is data indicating the relationship between the required voltage, which is the voltage that is the voltage, and the group of state quantities; a data storage unit storing certain second data,
The calculation unit is
a first step of acquiring the current cumulative operating time from the time measuring unit;
a second step of acquiring the state quantity group at the current time from the state quantity detection unit;
a third step of calculating the required voltage based on the first data from the state quantity group at the current point;
Based on the second data, from the operating time, which is the difference between the cumulative operating time at the previous time when the previous maintenance timing is calculated and the cumulative operating time at the current time, the state quantity group, and the required voltage, the a fourth step of calculating the amount of deterioration, which is the amount of change in the degree of deterioration of the spark plug during the calculation period, which is the period between the previous point in time and the present point in time;
A fifth step of calculating the degree of deterioration at the present time from the degree of deterioration and the amount of deterioration at the previous time;
A sixth step of calculating, from at least the deterioration degree at the present time and the accumulated operation time at the present time, the accumulated operating time when the degree of deterioration of the spark plug reaches a predetermined upper limit value as the maintenance timing of the spark plug. step,
is configured to execute a maintenance timing calculation process that is a process including
A device for calculating the maintenance timing of ignition plugs for heat pump engines. A maintenance timing calculation device for a spark plug of a heat pump engine according to claim 1,
The calculation unit is configured to execute the maintenance timing calculation process only in a state in which a fluctuation range of the state quantities constituting the state quantity group is less than a predetermined first threshold.
A device for calculating the maintenance timing of ignition plugs for heat pump engines. A maintenance timing calculation device for a spark plug of a heat pump engine according to claim 1 or claim 2,
The control unit changes the operating conditions of the engine and/or the compressor according to the required circulation amount when the required circulation amount of the heat medium changes, and changes the required circulation amount. If there is not, it is configured to execute a first control, which is a control for performing a process of not changing the operating conditions of the engine and / or the compressor, at each predetermined cycle,
At least when the operating conditions of the engine and/or the compressor are changed in the first control, the calculation unit calculates the timing at which the operating conditions of the engine and/or the compressor are changed in the first control. is configured not to execute the maintenance timing calculation process until a first period, which is a period having a predetermined length, elapses from
A device for calculating the maintenance timing of ignition plugs for heat pump engines. A maintenance timing calculation device for a spark plug of a heat pump engine according to any one of claims 1 to 3,
The calculation unit reduces the energization time and/or the voltage applied to the spark plug, thereby temporarily reducing the ignition output of the spark plug by a predetermined first amount. When the width is equal to or greater than a predetermined second threshold, deterioration degree correction processing, which is processing for increasing the current deterioration degree by a predetermined second amount, is executed.
A device for calculating the maintenance timing of ignition plugs for heat pump engines. at least an engine; at least one compressor driven by the engine; a circulation path that is a passage for circulating a heat medium from a discharge port of the compressor to an intake port of the compressor; and a control unit configured to control the operating state of the engine and/or the compressor, in which the maintenance timing of the spark plug provided in the engine is calculated, A maintenance timing calculation method for a spark plug of a heat pump engine, comprising:
A time measuring unit configured to measure the cumulative operating time of the engine from the time of installation or replacement of the spark plug to the present time, and a plurality of state quantities including at least the rotational speed and load of the engine. A state quantity detection unit including detection means configured to detect a group of state quantities, a calculation unit configured to calculate the maintenance timing, and a voltage applied to at least the discharge electrode of the spark plug. First data, which is data indicating the relationship between the required voltage, which is the voltage that is the voltage, and the group of state quantities; A maintenance timing calculation device for a spark plug of a heat pump engine, comprising: a data storage unit storing certain second data;
The calculation unit is
a first step of acquiring the current cumulative operating time from the time measuring unit;
a second step of acquiring the state quantity group at the current time from the state quantity detection unit;
a third step of calculating the required voltage based on the first data from the state quantity group at the current point;
Based on the second data, from the operating time, which is the difference between the cumulative operating time at the previous time when the previous maintenance timing is calculated and the cumulative operating time at the current time, the state quantity group, and the required voltage, the a fourth step of calculating the amount of deterioration, which is the amount of change in the degree of deterioration of the spark plug during the calculation period, which is the period between the previous point in time and the present point in time;
A fifth step of calculating the degree of deterioration at the present time from the degree of deterioration and the amount of deterioration at the previous time;
A sixth step of calculating, from at least the deterioration degree at the present time and the accumulated operation time at the present time, the accumulated operating time when the degree of deterioration of the spark plug reaches a predetermined upper limit value as the maintenance timing of the spark plug. step,
Execute maintenance timing calculation processing, which is processing including
A maintenance timing calculation method for a spark plug of a heat pump engine. A maintenance timing calculation method for a spark plug of a heat pump engine according to claim 5,
The calculation unit executes the maintenance timing calculation process only in a state in which a fluctuation range of the state quantities constituting the state quantity group is less than a predetermined first threshold.
A maintenance timing calculation method for a spark plug of a heat pump engine. A maintenance timing calculation method for a spark plug of a heat pump engine according to claim 5 or claim 6,
The control unit changes the operating conditions of the engine and/or the compressor according to the required circulation amount when the required circulation amount of the heat medium changes, and changes the required circulation amount. If there is not, it is configured to execute a first control, which is a control for performing a process of not changing the operating conditions of the engine and / or the compressor, at each predetermined cycle,
At least when the operating conditions of the engine and/or the compressor are changed in the first control, the calculation unit calculates the timing at which the operating conditions of the engine and/or the compressor are changed in the first control. The maintenance timing calculation process is not executed until a first period, which is a period having a predetermined length, has elapsed from
A maintenance timing calculation method for a spark plug of a heat pump engine. A maintenance timing calculation method for a spark plug of a heat pump engine according to any one of claims 5 to 7,
The calculation unit reduces the energization time and/or the voltage applied to the spark plug, thereby temporarily reducing the ignition output of the spark plug by a predetermined first amount. When the width is equal to or greater than a predetermined second threshold, executing deterioration degree correction processing, which is processing for increasing the current deterioration degree by a predetermined second amount;
A maintenance timing calculation method for a spark plug of a heat pump engine.

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