Patent Description:
When working with a construction machine, for example, an excavator, some operators may set a high-power mode, even when performing light-load operations. However, such a habit may lead to fuel wastage.

In the related art, a method of recommending an appropriate power mode to an operator has been proposed in order to overcome the problem of fuel wastage. Such a power mode recommendation method is designed to recommend a power mode indicating a lowest amount of fuel consumption on a single output curve of an engine fuel map.

However, the power mode recommendation method of the related art may have limited ability, since the operating speeds of excavators are not considered. For example, when engine angular velocity decreases and output torque increases under the same power conditions, fuel consumption tends to decrease. When a system controlling this power mode recommendation method only recommends a power mode consuming a lowest amount of fuel, engine angular velocity may decrease. Accordingly, an operator may not be satisfied by the operating speed under light-load conditions, since the maximum operating speed is determined by engine angular velocity under light-load conditions. According to its abstract, <CIT> relates to device for recommending a mode. The device comprises: an engine; a hydraulic pump driven by the engine; a control unit for pre-storing a suitable relationship between power and a mode; and an output unit, wherein the control unit calculates power by using the torque of the hydraulic pump and the number of revolutions of the engine, extracts, as a recommended mode, a mode corresponding to the calculated power from the relationship between power and a mode, and transmits the recommended mode to the output unit, and the output unit outputs the received recommended mode to a driver. Further <CIT> describes in its abstract a system for providing information about fuel efficiency of construction machinery, comprising: a TMS controller obtaining information about reference fuel efficiency through a communication network from a server, and providing the information about the reference fuel efficiency as display information; and an equipment controller calculating information about current fuel efficiency by analyzing operations of constituent elements of the construction machinery.

Various aspects of the present disclosure provide a power mode recommendation system for a construction machine that can recommend an efficiency power mode to an operator by analyzing not only the amount of fuel consumed by the construction machine, but also flow rates of working fluid in use and operating speeds.

According to an aspect, provided is a power mode recommendation system for recommending a power mode from among a plurality of power modes for operation of an engine of a construction machine, the construction machine including a hydraulic system driven by working fluid supplied by a hydraulic pump, the hydraulic system including a pressure sensor for sensing pressure of working fluid. The power mode recommendation system may include: a controller configured to analyze engine torque, flow rates of working fluid in use, amounts of fuel consumption of the plurality of power modes and to recommend a power mode indicating lowest fuel consumption, from among the plurality of power modes, using the analysis; and a human-machine interface (HMI) device displaying the power mode recommended by the controller to an operator.

The controller includes:
a torque calculator configured to calculate torque amounts of the engine according to the plurality of power modes, and based on the calculated torque amounts, select first candidate power modes from among the plurality of power modes; a minimum recommended power mode calculator configured to calculate minimum recommended power modes according to flow rates of working fluid, and based on the calculated minimum recommended power modes, select second candidate power modes from among the first candidate power modes; and a fuel consumption calculator configured to calculate amounts of fuel consumption of the second candidate power modes.

The torque calculator may include: a first calculator configured to calculate output torque and power of the engine in a current state, based on flow rates of working fluid discharged by the hydraulic pump, angular velocity of the engine, and pressure of hydraulic fluid transferred by the pressure sensor; and a second calculator configured to calculate torque amounts, capable of generating the same power as the power calculated by the first calculator, according to the plurality of power modes.

The torque calculator may further include a first determiner. When the torque amount of a specific power mode among the plurality of power modes, calculated by the second calculator, is greater than a preset maximum torque amount of the specific power mode, the first determiner may exclude the specific power mode from among the first candidate power modes.

The minimum recommended power mode calculator selects power modes from among the first candidate power modes, having higher engine angular velocity than the minimum recommended power modes, as the second candidate power modes.

The fuel consumption calculator may include a third calculator calculating amounts of fuel consumption of the second candidate power modes using fuel consumption data including torque and angular velocity.

The fuel consumption calculator may further include a second determiner selecting one power mode from among the second candidate power modes, indicating lowest fuel consumption during a monitoring period, as a final recommendation power mode, based on the calculated amounts of fuel consumption of the second candidate power modes.

The controller may further include an output unit transferring the final recommendation power mode, selected by the second determiner, to the HMI device.

The controller may further include a fuel efficiency calculator calculating average fuel efficiencies of the plurality of power modes.

The fuel efficiency calculator may calculate average loads of the plurality of power modes and calculate average fuel efficiencies during a specific period using the calculated average loads.

The fuel efficiency calculator may calculate real-time fuel efficiencies of the plurality of power modes, and based on the real-time fuel efficiencies, determine the average fuel efficiencies of the plurality of power modes.

The power mode recommendation may further include a power mode selecting device connected to the controller, wherein the power mode selecting device is manipulated by the operator to select one power mode from among the plurality of power modes.

As set forth above, the above-described power mode recommendation method according to the present disclosure can analyze not only the amount of fuel consumption of a construction machine, but also flow rates of working fluid in use and operating speeds, and based on the analysis, recommend an efficient power mode, in particular, an optimal power mode, to an operator as long as productivity is significantly reduced. This can consequently minimize fuel wastage while satisfying the operating speed of the construction machine.

According to the present disclosure, flow rates of working fluid are monitored, and even if there is a power mode, the fuel consumption of which is lower than the fuel consumption of the current power mode using a higher flow rate of working fluid, the power mode may not be recommended in consideration of the operating speed of the construction machine. Rather, another power mode indicating lower fuel consumption while maintaining the operating speed of the construction machine to a specific extent is recommended. It is thereby possible to satisfy both the amount of fuel consumption and the operating speed of the construction machine.

The methods and apparatuses of the present disclosure have other features and advantages that will be apparent from or that are set forth in greater detail in the accompanying drawings which are incorporated herein, and in the following Detailed Description, which together serve to explain certain principles of the present disclosure.

Hereinafter, a power mode recommendation system for a construction machine according to exemplary embodiments will be described in detail with reference to the accompanying drawings.

Throughout this document, reference should be made to the drawings, in which the same reference numerals and symbols will be used to designate the same or like components. In the following description, detailed descriptions of known functions and components incorporated in the present disclosure will be omitted in the case in which the subject matter of the present disclosure is rendered unclear by the inclusion thereof.

Referring to <FIG>, a power mode recommendation system according to an exemplary embodiment is a system for recommending a most efficient power mode, among a plurality of power modes for setting the output of an engine <NUM> in a construction machine, e.g. an excavator, to an operator, in which the recommended power mode is set to satisfy the operating speed of the excavator while minimizing fuel wastage.

The excavator includes a hydraulic system <NUM> for operating an actuator to move an attachment, such as a boom, an arm, and a bucket. The hydraulic system is driven by working fluid supplied by at least one hydraulic pump <NUM>. A hydraulic line is disposed between the hydraulic pump <NUM> and the hydraulic system <NUM> to provide a path along which working fluid flows, and a pressure sensor <NUM> is disposed on the hydraulic line to sense the pressure of working fluid supplied to the hydraulic system <NUM> by the hydraulic pump <NUM>.

The power mode recommendation system according to the exemplary embodiment analyzes not only the amount of fuel consumption, depending on the angular velocity of the engine, but also information regarding flow rates of working fluid provided by the pressure sensor <NUM> or the operating speed of the actuator, and based on the analysis, recommends an efficient or optimal power mode to the operator.

In this regard, the power mode recommendation system according to the exemplary embodiment includes a controller and a human-machine interface (HMI) device <NUM>.

The controller <NUM> controls flow rates of working fluid discharged by the hydraulic pump <NUM>. The controller <NUM> is connected to the engine <NUM> and the pressure sensor <NUM> to receive information regarding engine angular velocity and the pressure of working fluid therefrom. In addition, the controller <NUM> is connected to the HMI device <NUM> to transfer a selected power mode to the HMI device <NUM>, so that the HMI device <NUM> displays the power mode to be recommended to the operator. Then, the operator can visually recognize the recommended power mode displayed on the HMI device <NUM> and determine whether or not to apply the recommended power mode.

As described above, the controller <NUM> according to the exemplary embodiment analyzes torque, a flow rate of working fluid in use, an amount of fuel consumption in each of the plurality of power modes to recommend an efficient power mode to the operator via the HMI device <NUM>. Based on the analysis, the controller <NUM> recommends a power mode from among the plurality of power modes, indicating a lowest amount of fuel consumption without significantly decreasing the operating speed.

As apparent from the fuel map illustrated in <FIG>, according to the exemplary embodiment, a first power mode PwrMod_1, a second power mode PwrMod_2, a third power mode PwrMod_3, and a fourth power mode PwrMod_4 are set as a group of candidate power modes, depending on engine angular velocity. However, the group of candidate power modes may be set to include more than four power modes, and the group of candidate power modes, i.e. the plurality of power modes, are not limited to the first power mode PwrMod_1, the second power mode PwrMod_2, the third power mode PwrMod_3, and the fourth power mode PwrMod_4.

According to the exemplary embodiment, a currently applied power mode, i.e. a power mode in use prior to power mode recommendation by the controller <NUM>, is taken to be the third power mode PwrMod_3.

As illustrated in <FIG>, the controller <NUM> includes a receiver <NUM>, a torque calculator <NUM>, a minimum recommended power mode calculator <NUM>, a fuel consumption calculator <NUM>, and an output unit <NUM> to recommend a single most efficient power mode from among the above-stated plurality of power modes.

The receiver <NUM> receives a pressure of working fluid sensed by the pressure sensor <NUM>. The receiver <NUM> receives information regarding an engine angular velocity from the engine <NUM>. In addition, the receiver <NUM> transfers information regarding the pressure of working fluid and engine angular velocity to the torque calculator <NUM>.

The torque calculator <NUM> calculates the torque amounts of the engine <NUM> according to the plurality of power modes, and based on the calculated torque amounts, selects first candidate power modes from among the plurality of power modes. In this regard, as illustrated in <FIG>, the torque calculator <NUM> may include a first calculator <NUM>, a second calculator <NUM>, and a first determiner <NUM>.

The first calculator <NUM> calculates the output torque and power of the engine <NUM> in the current state, based on the flow rate of working fluid discharged by the hydraulic pump, the angular velocity of the engine <NUM>, and the pressure of working fluid.

The second calculator <NUM> calculates torque amounts, capable of generating the same power as the power calculated by the first calculator <NUM>, according to the plurality of power modes. <FIG> is a fuel map illustrating a constant power curve drawn by connecting the torque amounts of the plurality of power modes calculated by the second calculator <NUM>. Referring to <FIG>, power at a single point in a specific power mode can also be obtained at points in the remaining power modes. However, at the points indicating the same power, the plurality of power modes consume different amounts of fuel.

As illustrated in <FIG>, although power at a specific point (designated with a circle) in the third power mode PwrMod_3 is equal to power at a specific point (designated with a triangle) in the fourth power mode PwrMod_4, the specific point in the third power mode PwrMod_3 indicates lower fuel consumption than the specific point in the fourth power mode PwrMod_4.

In contrast, although power at the specific point in the third power mode PwrMod_3 is equal to power at a specific point (designated with a square) in the second power mode PwrMod_2, the specific point in the third power mode PwrMod_3 indicates higher fuel consumption than the specific point in the second power mode PwrMod_2.

When the torque amount of a specific power mode among the plurality of power modes, calculated by the second calculator <NUM>, is greater than a preset maximum torque amount of the specific power mode, the first determiner <NUM> excludes the specific power mode from among the first candidate power modes.

Referring to <FIG>, the calculated torque amount of the first power mode PwrMod_1, greater than the preset maximum torque amount of the first power mode PwrMod_1, may be excluded from among the first candidate power modes. This is because, when the operator changes the power mode of the excavator from the currently-operating mode, i.e. the third power mode PwrMod_3, to the first power mode PwrMod_1, the same amount of power as that of the third power mode PwrMod_3 cannot be generated. When the power mode of the excavator is changed from the currently-operating third power mode PwrMod_3 to the first power mode PwrMod_1, fuel consumption is lowered, with the compromise of operating speed. This may consequently lower workability, dissatisfying the operator.

<FIG> illustrates a fuel map different from the fuel map of <FIG>. Since the fuel map represents unique characteristics of the engine <NUM>, a variety of power modes may be recommended depending on the conditions of the excavator.

The minimum recommended power mode calculator <NUM> calculates minimum recommended power modes according to flow rates of working fluid. The minimum recommended power mode calculator <NUM> also selects second candidate power modes from among the first candidate power modes, based on the calculated minimum recommended power modes. Specifically, the minimum recommended power mode calculator <NUM> selects power modes from among the first candidate power modes, having higher engine angular velocity than the minimum recommended power modes, as the second candidate power modes.

Due to the above-described minimum recommended power mode calculator <NUM>, even in the case in which the operator changes the currently-operating power mode, e.g. the third power mode PwrMod_3, to a lower power mode, working fluid having a flow rate capable of maintaining the current operating speed to a specific extent can be supplied to the hydraulic system <NUM>.

Describing in more detail with reference to <FIG>, first, Tm indicates a period of time for which flow rates of working fluid of the power modes are monitored. T1 indicates a cumulative time for which a required flow rate Qdmd is greater than a maximum flow rate Qmax@PwrMod_1 of the first power mode PwrMod_1. T2 indicates a cumulative time for which the required flow rate Qdmd is greater than a maximum flow rate Qmax@PwrMod_2 of the second power mode PwrMod_2. The required flow rate Qdmd is controlled by the controller <NUM> so as not to be greater than a maximum flow rate Qmax@PwrMod_3 of the third power mode PwrMod_3.

In this condition, when a value T2/Tm is less than a minimum recommended power mode set value, the second power mode PwrMod_2 can be selected as a second candidate power mode. In contrast, when the value T1/Tm is greater than the minimum recommended power mode set value, the first power mode PwrMod_1 cannot be selected as a second candidate power mode. The minimum recommended power mode set value is a tuning parameter that does not significantly lower performance.

For example, a case in which T2/Tm is <NUM>%, T1/Tm is <NUM>%, and the minimum recommended power mode set value is <NUM>% is taken. In this condition, when the operator changes the currently-operating third power mode PwrMod_3 to the second power mode PwrMod_2, <NUM>% of the current operating speed can be satisfied. In contrast, if the operator changes the currently-operating third power mode PwrMod_3 to the first power mode PwrMod_1, <NUM>% of the current operating speed can be satisfied.

Since the minimum recommended power mode set value without a significant effect on operating speed is set to be <NUM>% according to the exemplary embodiment, the first power mode PwrMod_1 exceeding this value cannot be selected as a second candidate power mode, as in the selection of first candidate power modes.

According to the exemplary embodiment, the first power mode PwrMod_1 is excluded from among the candidate power modes by the torque calculator <NUM> and the minimum recommended power mode calculator <NUM>, and the second power mode PwrMod_2, the third power mode PwrMod_3, and the fourth power mode PwrMod_4 remain as the second candidate power modes.

The fuel consumption calculator <NUM> calculates amounts of fuel consumption of the second candidate power modes. As illustrated in <FIG>, the fuel consumption calculator <NUM> may include a third calculator <NUM> and a second determiner <NUM>.

The third calculator <NUM> calculates amounts of fuel consumption of the second candidate power modes, i.e. the second power mode PwrMod_2, the third power mode PwrMod_3, and the fourth power mode PwrMod_4, using fuel consumption data including torque Tq and angular velocity ω.

The second determiner <NUM> selects one power mode from among the second candidate power modes, indicating lowest fuel consumption during the monitoring period, as a final recommendation power mode, based on the amounts of fuel consumption of the second candidate power modes calculated by the third calculator <NUM>.

Referring to <FIG>, the second power mode PwrMod_2 indicates lower fuel consumption than the third power mode PwrMod_3 and the fourth power mode PwrMod_4. Thus, according to the exemplary embodiment, the second determiner <NUM> selects the second power mode PwrMod_2 as the final recommendation power mode for an efficient operation.

The above-described power mode recommendation method can recommend an efficient power mode, in particular, an optimal power mode, to the operator as long as productivity is significantly reduced. This can consequently minimize fuel wastage while satisfying the operating speed of the construction machine.

The output unit <NUM> transfers the second power mode PwrMod_2, i.e. the final recommendation power mode selected by the second determiner <NUM>, to the HMI device <NUM>.

The controller <NUM> according to the exemplary embodiment may further include a fuel efficiency calculator <NUM>. The fuel efficiency calculator <NUM> calculates average fuel efficiencies of the plurality of power modes. After average loads of the plurality of power modes are calculated, the fuel efficiency calculator <NUM> may calculate average fuel efficiencies during a specific period using the calculated average loads. However, the average fuel efficiencies may be inaccurate when calculated in this manner.

To overcome this problem, according to another exemplary embodiment, the fuel efficiency calculator <NUM> may calculate fuel efficiencies of the plurality of power modes in real time, and based on the real-time fuel efficiencies, determine average fuel efficiencies of the plurality of power modes.

The HMI device <NUM> may be disposed in the cab of the excavator. The HMI device <NUM> displays the final recommendation power mode recommended by the controller <NUM>, e.g. the second power mode PwrMod_2, to be visually recognizable by the operator.

The power mode recommendation system according to the exemplary embodiment may further include a power mode selecting device <NUM>.

The power mode selecting device <NUM> may be disposed in the cab of the excavator together with the HMI device <NUM>. The operator manipulates the power mode selecting device <NUM> to select one power mode from among the plurality of power modes. The operator ultimately determines a power mode to be applied through reference to the final recommendation power mode displayed on the HMI device <NUM>. When a single power mode is selected by the operator, the power mode selecting device <NUM> connected to the controller <NUM> transfers the selected power mode to the controller <NUM>.

The power mode selected by the operator may be the final recommendation power mode recommended by the controller <NUM>. However, final selection of a power mode depends on the operator.

Hereinafter, an operation of the power mode recommendation system for a construction machine according to an exemplary embodiment will be described with reference to <FIG>. As for the reference numerals of the components, <FIG> will be referred to.

As illustrated in <FIG>, in a first step S1, the power mode recommendation system for a construction machine according to the exemplary embodiment calculates output torque and power of the engine <NUM>, based on a flow rate of working fluid discharged by the hydraulic pump <NUM>, a angular velocity of the engine <NUM>, and a pressure of working fluid.

Afterwards, in a second step S2, torque amounts capable of generating the same power as calculated in the first step S1 are calculated, according to a plurality of power modes.

In sequence, in a third step S3, when the torque amount of a specific power mode among the plurality of power modes, calculated in the second step S2, is greater than a preset maximum torque amount of the specific power mode, the specific power mode is excluded from among first candidate power modes.

Afterwards, in a fourth step S4, a minimum recommended power mode is calculated depending on the flow rate of working fluid. Here, in S4-<NUM>, a power mode having a higher flow rate of working fluid than the flow rate of working fluid of the minimum recommended power mode is selected as a candidate power mode.

In sequence, in a fifth step S5, amounts of fuel consumption of the candidate power modes are calculated using fuel consumption data S5-<NUM> including torque Tq and angular velocity ω.

Afterwards, in a sixth step S6, one power mode among the candidate power modes, indicating lowest fuel consumption during the monitoring period, is selected as a final recommendation power mode, based on the amounts of fuel consumption of the candidate power modes.

Finally, in a seventh step S7, the selected power mode is recommended to the operator. The selected power mode may be displayed on the HMI device <NUM> to be visually recognizable to the operator. Then, the operator can check the displayed power mode and can ultimately select a power mode to be applied to the excavator by manipulating the power mode selecting device <NUM>.

Claim 1:
A power mode recommendation system for recommending a power mode from among a plurality of power modes for operation of an engine(<NUM>) of a construction machine, the construction machine including a hydraulic system (<NUM>) driven by working fluid supplied by a hydraulic pump (<NUM>), the hydraulic system including a pressure sensor (<NUM>) for sensing pressure of working fluid, the power mode recommendation system comprising:
a controller (<NUM>) configured to analyze engine torque, flow rates of working fluid in use, amounts of fuel consumption of the plurality of power modes and to recommend a power mode indicating lowest fuel consumption, from among the plurality of power modes, using the analysis; and
a human-machine interface device (<NUM>) displaying the power mode recommended by the controller to an operator,
wherein the controller comprises:
a torque calculator (<NUM>) configured to calculate torque amounts of the engine according to the plurality of power modes, and based on the calculated torque amounts, select first candidate power modes from among the plurality of power modes;
a minimum recommended power mode calculator configured to calculate minimum recommended power modes according to flow rates of working fluid, and based on the calculated minimum recommended power modes, select second candidate power modes from among the first candidate power modes; and
a fuel consumption calculator (<NUM>) configured to calculate amounts of fuel consumption of the second candidate power modes,
wherein the minimum recommended power mode calculator selects power modes from among the first candidate power modes, having higher engine angular velocity than the minimum recommended power modes, as the second candidate power modes.