System and method for operating engine of work machine

Abstract

A method of operating an engine of a work machine via a controller includes: detecting a request for a transmission shift of a transmission of the work machine from a neutral gear to a desired start gear; determining a current transmission output speed of the transmission; determining a desired transmission output speed of the transmission corresponding to the desired starting gear; determining a desired minimum speed of the engine based on a difference between the current transmission output speed and the desired transmission output speed; and based on the request for the transmission shift, operating the engine at or above the desired minimum speed prior to completion of the transmission shift from the neutral to the desired start gear.

Description

Technical Field

[0001] This disclosure relates to working machines (such as motorized graders) used in earthmoving operations, and more specifically, to systems and methods for operating an internal combustion engine of a working machine in response to directly starting the working machine into a high-speed starting gear. Background Technology

[0002] A type of work machine applicable to construction and mining environments (such as a motorized grader or loader) typically includes a transmission that transmits rotational power from the machine's power source (e.g., an internal combustion engine) to one or more traction devices. In doing so, the transmission facilitates the movement of the machine. Such transmissions typically switch between multiple gears (e.g., neutral, forward, and reverse) to appropriately allow the machine to travel at different speeds.

[0003] If you attempt to start (or accelerate) the work machine to an alternative high-speed starting gear (e.g., fourth gear) instead of a standard low-speed starting gear (such as first, second, or third gear) while the engine is running at or near its minimum idle speed, the engine may experience a surge in drivetrain load. Such a surge in drivetrain load can lead to insufficient engine power or stalling.

[0004] U.S. Patent 11,591,774 discloses a system and method for compensating for reduced track speed due to engine deceleration of a working machine. The system includes a frame, an attachment coupled to the frame, a ground engagement mechanism adapted to support the frame, an engine, a motor, a track speed sensor, an engine speed sensor, and a controller. The engine can drive the ground engagement mechanism and the attachment. The engine can be coupled to the ground engagement mechanism and the attachment via a variable speed transmission. The variable speed transmission may include a hydrostatic circuit. When the working machine engages an increased load, the controller is adapted to send an increased transmission command signal based on a decrease in the engine speed signal. This increased transmission command signal can increase the motor speed to increase the track speed, thereby compensating for at least a portion of the reduced track speed caused by the decrease in engine speed. Summary of the Invention

[0005] In one aspect, this disclosure relates to a method for operating the engine of a work machine via a controller. The method includes detecting a request to shift a transmission gear of the work machine from neutral to a desired starting gear. Furthermore, the method includes determining a current transmission output speed of the transmission. Furthermore, the method includes determining a desired transmission output speed of the transmission corresponding to the desired starting gear. Furthermore, the method includes determining a desired minimum speed of the engine based on the difference between the current transmission output speed and the desired transmission output speed. Furthermore, the method includes, based on the request to shift the transmission gear, causing the engine to operate at the desired minimum speed or a speed higher than the desired minimum speed before completing the transmission shift from neutral to the desired starting gear.

[0006] In another aspect, this disclosure relates to a working machine. The working machine includes: an engine; a transmission operatively coupled to the engine to transmit power to one or more traction devices of the working machine, thereby facilitating machine movement; and a control system for operating the engine. The control system includes a controller. The controller is configured to detect a request to shift the transmission from neutral to a desired starting gear. The controller is further configured to determine the current transmission output speed of the transmission. Furthermore, the controller is configured to determine a desired transmission output speed of the transmission corresponding to the desired starting gear. Additionally, the controller is configured to determine a desired minimum speed of the engine based on the difference between the current transmission output speed and the desired transmission output speed. Furthermore, the controller is configured to, based on the request to shift the transmission, cause the engine to operate at the desired minimum speed or a speed higher than the desired minimum speed before completing the transmission shift from neutral to the desired starting gear.

[0007] In another aspect, this disclosure relates to a control system for an engine used to operate a work machine. The control system includes a controller. The controller is configured to detect a request to shift a transmission gear of the work machine from neutral to a desired starting gear. The controller is further configured to determine the current transmission output speed of the transmission. Furthermore, the controller is configured to determine a desired transmission output speed of the transmission corresponding to the desired starting gear. Additionally, the controller is configured to determine a desired minimum speed of the engine based on the difference between the current transmission output speed and the desired transmission output speed. Furthermore, the controller is configured to, based on the request to shift the transmission gear, cause the engine to operate at the desired minimum speed or a speed higher than the desired minimum speed before completing the transmission shift from neutral to the desired starting gear. Attached Figure Description

[0008] Figure 1 Exemplary operating machines according to embodiments of the present disclosure are illustrated;

[0009] Figure 2 This is a schematic diagram of the power system of a machine, depicting a combination of the machine's control system and various other components according to embodiments of the present disclosure.

[0010] Figure 3 This is a flowchart illustrating a method of operating the engine of a work machine according to an embodiment of the present disclosure; and

[0011] Figure 4 The following graphs are illustrated according to embodiments of the present disclosure: (a) engine speed and time; (b) selected gear and time; (c) transmission output speed and time; and (d) micro pedal position and time. Detailed Implementation

[0012] Reference will now be made in detail to specific embodiments or features, examples of which are illustrated in the accompanying drawings. Generally, corresponding reference numerals may be used throughout the drawings to refer to the same or corresponding parts; for example, 1, 1', 1'', 101, and 201 may refer to one or more equivalent components used in the same and / or different depicted embodiments.

[0013] refer to Figure 1 An exemplary working machine 100 (hereinafter referred to as "machine 100") is shown. Machine 100 can perform a variety of operations associated with industries such as construction, mining, farming, transportation, or any other industry known in the art. As an example, machine 100 is embodied as a motorized grader 100', which is configured to perform functions such as earthmoving functions on the ground or working surface 102 via one or more of its implements, including moving, expanding, distributing, leveling, and smoothing materials such as soil.

[0014] Alternatively, machine 100 can be any working machine, including but not limited to backhoe loaders, excavators, tractor-trailers, bulldozers, tracked tractors, forklifts, skid steer loaders, and multi-terrain loaders. Therefore, it is understood that aspects of this disclosure are not limited to any particular type of machine, and references to machine 100 (which is depicted above and considered to be a motorized grader) are purely exemplary.

[0015] Machine 100 may include a frame 104. Frame 104 may include a rigid structure to which virtually every other component (and / or sub-component) of machine 100 may be coupled. Furthermore, machine 100 may include one or more traction devices 108. The traction device 108 may be in the form of a wheeled, tracked traction device, or a combination thereof. The traction device 108 may be supported on frame 104. Actuation of the traction device 108 allows frame 104 (and thus machine 100) to move on ground 102.

[0016] Furthermore, as shown in the figure, machine 100 may include a front end portion 116 and a rear end portion 120. It can be noted that, as used herein, the terms “front” and “rear” in relation to the ends (i.e., front end portion 116 and rear end portion 120) and other aspects are related to the exemplary direction of travel of machine 100 (e.g., Figure 1 (As indicated by the arrow T). The direction of travel is exemplarily defined as extending from the rear end 120 of machine 100 toward the front end 116 of machine 100, as shown. It is understood that arrow T indicates the forward direction of machine 100.

[0017] refer to Figure 1 and Figure 2 The machine 100 may also include several other components and subsystems, such as a power compartment 124, which may be supported on the frame 104 and house the power source 128 of the machine 100. The power source 128 may include an internal combustion engine (or simply engine 132 below) for generating power to operate various functions associated with the machine 100. For example, the engine 132 may be part of the power system 136 of the machine 100 and may be operatively coupled to a traction device 108 via various other components of the power system 136 to power the operation of the traction device 108 and enable the machine 100 to move on the ground 102. The engine 132 may operate on fuel such as diesel, gasoline, or natural gas, which may be used alone or in combination in the engine 132. Various discussions in this disclosure refer to the engine 132 and its associated components; however, all such references to the engine 132 may be considered exemplary, as the power source 128 may also include suitable equivalents or other types of power generation devices, such as hybrid power generation devices.

[0018] The machine 100 may also include a transmission 140 as part of the powertrain 136. The transmission 140 facilitates the regulation of the power generated by the engine 132 and transmits that power all the way to the traction device 108 of the machine 100. Similar to the power source 128, the transmission 140 may also be supported on the frame 104. The transmission 140 may define a number of different gears (e.g., neutral, first forward gear, fourth forward gear, second reverse gear, etc.) (not shown), which may be selectively engaged via one or more clutches (not shown) to enable the machine 100 to move at varying speeds in both the forward direction (arrow T) and the reverse direction.

[0019] The transmission 140 may be adapted to be operatively coupled to a power source 128 (e.g., engine 132) to receive power from the power source 128 (e.g., engine 132). Such coupling may be exemplarily achieved by selectively using one or more clutches (such as one or more first clutches and one or more second clutches (not shown)). As an example, if movement in the forward direction is required in a first forward gear, the one or more first clutches may be engaged to operatively engage the input shaft (not shown) of the transmission 140 with the output end (e.g., flywheel) of the engine 132, such that the machine 100 can achieve the movement at a first desired speed in the first forward gear; and if movement in the forward direction is required in a second forward gear, the one or more second clutches may be engaged to operatively engage the input shaft with the output end of the engine 132, such that the machine 100 can achieve the movement at a second desired speed in the second forward gear, and so on.

[0020] Furthermore, the transmission 140 may also include a transmission output shaft 144 through which power output (e.g., rotational power output) received from the power source 128 (e.g., engine 132) can be transmitted to other components of the powertrain 136. For example, such power output could be transmitted to a propeller shaft 148 of the powertrain 136, which could then further transmit the power output to a traction device 108 to facilitate machine movement. It should be understood that transmission types other than those discussed herein are conceivable. For example, a hydraulic transmission or a hybrid transmission could be used if desired. Furthermore, as... Figure 2 The layout of the powertrain 136, as illustrated and described herein, is also exemplary.

[0021] In some embodiments, each of the power source 128 and the transmission 140 may include a corresponding electronic control module (i.e., ECM). For example, when an engine 132 is included, the power source 128 may include an engine ECM 152, and the transmission 140 may include a transmission ECM 156. Among other engine-related functions, the engine ECM 152 may also be configured to regulate the fuel supply to the engine 132 to power the engine 132. Among other transmission-related functions, the transmission ECM 156 may also be configured to enable the transmission 140 to shift gears between various gears to allow the machine 100 to achieve different speeds and / or to enable the machine 100 to move in different (i.e., forward or backward) directions.

[0022] In addition, continue to refer to Figure 1 and Figure 2Machine 100 may include an operator's cab 160 mounted on top of frame 104. The operator's cab 160 allows one or more operators of machine 100 to be accommodated and reside therein. The operator's cab 160 may include various controls and operator interfaces in the form of displays, joysticks, touchscreens, control panels, and joysticks (see [link to relevant documentation]). Figure 2 The joystick 164 and micro pedal 168, among other controls and operator interfaces, enable one or more operators of machine 100 to feed requests or inputs to control a variety of functions of machine 100. For example, operators can use such controls to control the operation of power source 128 and transmission 140, thereby facilitating and controlling machine movement. For example, by using such controls (e.g., joystick 164 and micro pedal 168), one or more operators can request, for example, a transmission shift from neutral to a desired starting gear. While it has been discussed that various controls (e.g., joystick 164) be housed within operator cab 160, optionally or additionally, such controls may also be positioned remotely from machine 100.

[0023] In addition, machine 100 may include various sensors. For example, machine 100 may include a speed sensor 172 that facilitates the detection of the ground speed of machine 100. For example, speed sensor 172 may be configured to detect the transmission output speed (e.g., rotational speed in revolutions per minute (RPM)) of the transmission output shaft 144, based on which the ground speed of machine 100 can be inferred (e.g., in real time). The speed sensor 172 may be communicatively coupled to transmission ECM 156, such that data from speed sensor 172 can be received, processed, stored, etc., by transmission ECM 156.

[0024] Furthermore, in some embodiments, machine 100 may include a position sensor (not shown) that facilitates the detection of the position of the micro pedal 168. This position sensor may generate a signal proportional to the position of the micro pedal 168, which in one embodiment may be expressed as a percentage, where 100% is a fully depressed pedal and 0% is a fully extended pedal. It should be understood that during operation, when the micro pedal 168 is 100% depressed, one or more clutches of transmission 140 may be disengaged to disengage the input shaft (not shown) of transmission 140 from the output of engine 132 (e.g., flywheel) to limit power transmission from engine 132 to traction device 108, while when the micro pedal is 0% depressed (i.e., fully extended), one or more clutches of transmission 140 may be disengaged to engage the input shaft (not shown) of transmission 140 with the output of engine 132 (e.g., flywheel), thereby facilitating power transmission from engine 132 to traction device 108. The position sensor can be communicatively connected to the transmission ECM 156, so that data from the position sensor can be received, processed, and stored by the transmission ECM 156.

[0025] One or more aspects of this disclosure relate to a control system 176 of machine 100, which controls the operation of engine 132 when a transmission shift is requested to start (or accelerate) machine 100 to a desired starting gear instead of a standard starting gear. It should be understood that the term "standard starting gear" can be used for a low gear of transmission 140, where, once engaged, the drivetrain load applied to engine 132 cannot exceed the torque capacity of engine 132 at its minimum idle speed, and the term "desired starting gear" can be used for a high gear of transmission 140 (above the standard starting gear), where, upon engagement, the drivetrain load applied to engine 132 can exceed the torque capacity of engine 132 at its minimum idle speed, resulting in insufficient power or stalling of engine 132. Furthermore, it should be noted that the standard starting gear and the desired starting gear can vary depending on the type of machine 100 (e.g., machine weight), engine configuration (e.g., torque capacity), transmission configuration (e.g., gear ratio), and / or other factors. For example, for a motorized grader 100' (such as...), the term "desired starting gear" can vary depending on the type of machine 100 (e.g., machine weight), engine configuration (e.g., torque capacity), transmission configuration (e.g., gear ratio), and / or other factors. Figure 1 As shown), the standard starting gears may include the first, second, and third gears in both forward and reverse drive, while the desired starting gears may include any available gear above the third gear, such as the fourth gear, etc.

[0026] Control system 176 can operate engine 132 in a manner that facilitates successful starting (or acceleration) of machine 100 to the requested desired starting gear. To this end, control system 176 includes controller 180, which can control the operation of engine 132 in a manner that facilitates starting or accelerating machine 100 to the desired starting gear without causing engine 132 to become underpowered or stall. In other words, controller 180 controls the operation of engine 132 such that, in response to a request for a transmission shift from neutral to the desired starting gear (above the standard starting gear), the minimum speed of engine 132 is appropriately controlled (e.g., increased and / or decreased) before the transmission shift from neutral to the desired starting gear is completed. Various aspects related to controller 180 will be discussed further below.

[0027] Controller 180 may (e.g., wirelessly or via a suitable data link) be communicatively coupled to the ECM of each of engine 132 and transmission 140. For example, controller 180 may be communicatively coupled to engine ECM 152 and transmission ECM 156. According to one embodiment of this disclosure, controller 180 may operate in a closed-loop manner relative to one or more of engine ECM 152 and transmission ECM 156, dynamically (e.g., in real time) determining differences associated with machine motion, and may provide instructions to engine 132 via its corresponding engine ECM 152 such that machine 100 may be appropriately started or accelerated to a higher desired starting gear (e.g., fourth or fifth forward gear) without causing engine 132 to become underpowered or stall.

[0028] Furthermore, controller 180 may be communicatively coupled to one or more controls (e.g., joystick 164). According to one aspect of this disclosure, joystick 164 may be an input device 184, the use and / or manipulation of which facilitates input feeding or a request for gear shifting of transmission 140. Additionally, controller 180 may be coupled to memory unit 188, which may store various instruction sets, from which controller 180 may retrieve and execute one or more instruction sets. In doing so, controller 180 may control the operation of engine 132 by controlling (e.g., raising and / or lowering) a minimum speed of engine 132, and enable a smooth execution of starting (or accelerating) of machine 100 into a higher desired starting gear. The detailed operation of controller 180 implemented through this scheme is illustrated later in this disclosure with some examples.

[0029] Controller 180 may be integrated with and / or connected to any module in the machine's modules (such as a safety module or a dynamic module), or may be configured as a separate entity. Optionally, controller 180 may be integrated and may be any one of the aforementioned ECMs of machine 100, as discussed above. In some embodiments, these ECMs (i.e., engine ECM 152 and transmission ECM 156) may be integrated together into a single control module entity to define controller 180. Alternatively, controller 180 may form part of one or more of the aforementioned ECMs, although controller 180 may be independent and separate as a completely different entity.

[0030] Furthermore, controller 180 may be a microprocessor-based device and / or may be conceived as an application-specific integrated circuit or other logic device providing controller functionality, and such devices are known to those skilled in the art. In one example, controller 180 may include or represent one or more controllers having processing units configured individually or integrally to process various data (or inputs). Additionally, controller 180 may be optimally suited for housing within certain machine panels or sections, maintaining accessibility from these panels or sections for ease of use, maintenance, calibration, and repair.

[0031] In some cases, controller 180 may be hardwired to joystick 164 and connected to various other components and devices associated with machine 100, such as ECMs (i.e., engine ECM 152 and transmission ECM 156) and sensors (i.e., position sensors) connected to machine 100. Optionally, controller 180 may also be deployed at a remote site, either close to or far from joystick 164.

[0032] The processing unit used to convert and / or process signals / data from joystick 164, speed sensor 172, position sensor, etc. may include, but is not limited to, x86 processor, reduced instruction set computing (RISC) processor, application-specific integrated circuit (ASIC) processor, complex instruction set computing (CISC) processor, advanced RISC machine (ARM) processor, or any other processor.

[0033] Examples of memory unit 188 may include hard disk drives (HDDs) and secure digital storage (SD) cards. Furthermore, memory unit 188 may include non-volatile / volatile memory units, such as random access memory (RAM) / read-only memory (ROM), which may include associated input and output buses. Memory unit 188 may be configured to store the instruction set, which can be executed by controller 180 to perform methods for operating engine 132 in response to a request for a transmission shift from neutral to a higher desired starting gear, as discussed in this disclosure.

[0034] Industrial applicability

[0035] During exemplary operation, when machine 100 is parked stationary on ground 102 (e.g., at a road intersection), and when transmission 140 is in neutral and the engine is running at its minimum idle speed, the operator of machine 100 may wish to drive (or start) machine 100 through the road intersection at a higher speed. To do this, the operator may request a transmission shift from neutral to a desired starting gear (e.g., a higher gear, such as fourth gear) higher than the standard starting gear (low gear, such as first, second, or third gear). When shifting from neutral to such a higher desired starting gear, engine 132 may experience a surge in drivetrain load. Engine 132 running at minimum idle speed may not be able to generate sufficient power to meet such a surge in drivetrain load. This may result in insufficient engine power or stalling.

[0036] The control system 176 of this disclosure facilitates control over the operation of the engine 132, enabling the machine 100 to be started or accelerated to a desired starting gear (rather than a standard starting gear or a low gear) without causing the engine 132 to become underpowered or stall. In other words, the controller 180 controls the operation of the engine 132 such that, in response to a request for a transmission shift from neutral to the desired starting gear (fourth forward gear), the minimum speed of the engine 132 is appropriately controlled (e.g., increased and decreased) before the transmission shift from neutral to the desired starting gear is completed.

[0037] refer to Figure 3 The operation of the control system 176 for operating the engine 132 of machine 100 is explained by way of example. The method is as follows: Figure 3 The flowchart 300 shown provides examples and discussions, and also incorporates... Figure 1 , Figure 2 and Figure 4 The discussion took place. The method begins at step 304.

[0038] At step 304, when machine 100 is parked at a road intersection, transmission 140 is in neutral, and the engine is running at its minimum idle speed, the operator of machine 100 may wish to drive (or start) machine 100 through the road intersection at a higher speed. For this purpose, the operator may request a transmission shift from neutral to the desired starting gear (e.g., fourth forward gear) (see [link to relevant documentation]). Figure 4 The selected gear and time curve AB of graph 192. The request can be fed through input device 184 (e.g., joystick 164). Since controller 180 can operatively communicate with input device 184, controller 180 can detect such requests. Figure 4 As shown, during this phase (i.e., at time T1), engine 132 operates at approximately 800 RPM (see...). Figure 4 Point C on the engine speed curve (shown as solid curve 196) of the engine speed versus time graph 200, and the micro pedal 168 is in the 100% depressed position (see...). Figure 4 Point D on curve 204 of graph 208 (the position-time curve of the micro-pedal) disengages engine 132 from transmission 140. As used herein, the term "approximately" may refer to a value "within engineering tolerances". For example, unless otherwise indicated, approximately 800 RPM may mean between 780 RPM and 820 RPM, and so on.

[0039] In response to a request to shift gears, at step 308, controller 180 may determine the current transmission output speed of transmission output shaft 144 (of transmission 140), and at step 312, controller may determine the desired transmission output speed of transmission output shaft 144 corresponding to the selected desired starting gear.

[0040] To determine the current transmission output speed of the transmission output shaft 144, the controller 180 may retrieve data related to the speed of the transmission output shaft 144 (e.g., rotational speed in RPM) from the speed sensor 172 or from the transmission ECM 156, which is in communication with the speed sensor 172. In one example, at this stage (i.e., at time T1), the controller 180 may determine the current transmission output speed of the engine 132 as zero (see [reference]). Figure 4 Point E on curve 212 of graph 216 (output speed versus time of the transmission).

[0041] To determine the desired transmission output speed corresponding to the selected desired starting gear on the transmission output shaft 144, the controller 180 may retrieve data related to the speed of the transmission output shaft 144 (e.g., rotational speed in RPM) from the memory unit 188. For example, upon detecting a transmission shift from neutral to fourth forward gear, the controller 180 may use a lookup table (pre-stored in the memory unit 188 of the controller 180) to determine that the desired transmission output speed is approximately 400 RPM. In some embodiments, the controller 180 may receive the desired transmission output speed data from the transmission ECM 156.

[0042] The controller 180 can compare the current transmission output speed with the desired transmission output speed to infer the difference between the two. Based on the difference between the current and desired transmission output speeds, at step 316, the controller 180 can determine the desired minimum speed of the engine 132. In one example, if the difference between the current and desired transmission output speeds is below a threshold (pre-stored in the memory unit 188 of the controller 180), the controller 180 can determine that the desired minimum speed is equal to the current minimum idle speed of the engine 132 (e.g., approximately 800 RPM) (pre-stored in the memory unit 188 of the controller 180).

[0043] If the difference between the current transmission output speed and the desired transmission output speed is higher than a threshold, the controller 180 may determine that the desired minimum speed is higher than the current minimum idle speed of the engine 132. That is, when it is determined that the current transmission output speed is significantly lower than the desired transmission output speed, and the engine 132, operating at the current minimum idle speed at the time of a transmission shift, may not generate sufficient power to drive the machine 100 at the desired transmission output speed, the controller 180 may determine that the desired minimum speed is higher than the current minimum idle speed, and therefore raises the minimum speed from the current minimum idle speed to the desired minimum speed. In one example, such as Figure 4 As shown by the dashed line 220 (indicating the desired speed of engine 132) in the engine speed versus time graph 200, the controller 180 can increase the minimum speed of engine 132 from its current value of approximately 800 RPM (current minimum idle speed) to a relatively higher desired minimum speed value, for example, to approximately 900 RPM (see point F in dashed line 220).

[0044] Once the minimum speed is increased to the desired minimum speed, at step 320, the controller 180 can cause the engine 132 to operate at the desired minimum speed or a speed higher than the desired minimum speed (e.g., at 900 RPM or higher) before completing the transmission shift from neutral to the desired starting gear (e.g., fourth gear). To this end, the controller 180 can command the engine 132 (e.g., via engine ECM 152) to increase the fuel supply to a level such that the output speed of the engine 132 can be increased and maintained at or above the desired minimum speed (e.g., 900 RPM). The controller 180 may execute steps 308 to 320 in the same time period, during which one or more clutches begin to move from a fully disengaged position (e.g., when the micro pedal 168 is in a 100% depressed position (for disengaging the engine 132 and transmission 140, i.e. at point D) toward a fully engaged (or locked) position (e.g., when the micro pedal 168 is in a 0% depressed position) for engaging the engine 132 and transmission 140.

[0045] The controller 180 can increase the minimum speed of the engine 132 from the current minimum idle speed to the desired minimum speed at an increase rate proportional to the difference between the current transmission output speed and the desired transmission output speed. That is, the greater the difference between the current transmission output speed and the desired transmission output speed, the higher the increase rate. This increase rate can define how quickly the minimum speed can rise from the current minimum idle speed to the desired minimum speed. The increase rate can be defined in engine speeds per second (RPM). Furthermore, the controller 180 can limit the increase rate of the minimum speed below a predefined increase rate, for example, to eliminate any sudden spikes in the engine speed and improve the driving capability of the machine 100. This predefined increase rate can be pre-stored in the memory unit 188 of the controller 180, or alternatively, it can be input by the operator.

[0046] Furthermore, controller 180 may repeat steps 308 to 320 until the ground speed of machine 100 begins to increase (e.g., until machine 100 begins to move from a standstill). In other words, controller 180 may further increase the desired minimum speed of engine 132 from its current value to a relatively higher value, and may operate engine 132 at a relatively higher value than or above the desired minimum speed. For example, if it is determined that engine 132 operating at the desired minimum speed (e.g., approximately 900 RPM) may not provide sufficient power (torque) to propel machine 100 (from a standstill), controller 180 may further increase the minimum speed of engine 132 from its current value of the desired minimum speed (e.g., approximately 900 RPM) to a relatively higher value (e.g., approximately 1100 RPM) (see point G on dashed curve 220), and operate engine 132 at that relatively higher value than or above the desired minimum speed.

[0047] The controller 180 can continue to increase the desired minimum speed until the machine 100 begins to move from a standstill. For example, as Figure 4 As shown, controller 180 can detect movement of machine 100 (from rest) (at time T2) in response to running engine 132 at a speed of 1300 RPM or higher (the increase in desired minimum speed) (see point H in dashed curve 220). From point H, controller 180 may not further increase the desired minimum speed to a value higher than 1300 RPM.

[0048] Once machine 100 begins to move (accelerate) from rest (i.e., at time T2), controller 180 can reduce the minimum speed of engine 132 from the current value of the desired minimum speed (i.e., 1300 RPM, point H), for example, to equalize with the engine speed requested by the operator (i.e., the engine speed corresponding to the accelerator pedal position, for example, 1000 RPM) (see point I on dashed curve 220). Controller 180 can reduce the minimum speed of engine 132 from the desired minimum speed to equalize with the engine speed requested by the operator before completing the requested transmission shift, thereby avoiding any engine speed overshoot that could produce undesirable acceleration or jerking motion during the startup of machine 100.

[0049] The controller 180 can reduce the minimum speed from a desired minimum speed to an operator-requested engine speed at a decreasing rate. This decreasing rate defines how quickly the minimum speed can decrease from the desired minimum speed to the operator-requested engine speed. This decreasing rate can be defined in engine speeds per second (RPM). The controller 180 can set this decreasing rate based on the difference between the desired minimum speed and the operator-requested engine speed and / or the remaining time required to complete the requested transmission shift, i.e., the difference between time periods T2 and T3 (the time it takes for the microped to reach 0% depress to fully engage the engine 132 and transmission 140). The controller 180 can limit this decreasing rate of the minimum speed below a predefined decreasing rate. This predefined decreasing rate can be pre-stored in the controller 180's memory unit 188, or alternatively, it can be input by the operator.

[0050] Because control system 176 facilitates controlling the minimum speed of engine 132 when starting (or accelerating) machine 100 directly from a standstill to a high gear instead of a standard starting gear, as mentioned above, the output speed of engine 132 is sufficiently increased to the desired minimum speed at which, before completing the transmission shift to the selected high gear, engine 132 can provide sufficient power (torque) to propel machine 100 to the selected high gear, thus preventing stalling or underpowerment. Furthermore, control system 176 facilitates a reduction in the minimum speed, for example, equalizing the engine speed with the operator's requested speed once the machine begins to move before completing the transmission shift. This is to avoid any engine speed overshoot that could produce unwanted acceleration or jerking motion during the start-up of machine 100.

[0051] Unless explicitly excluded, the use of the singular to describe a component, structure, or operation does not preclude the use of multiple such components, structures, operations, or their equivalents. In the context of describing the invention (particularly in the context of the appended claims), the use of the terms “a,” “an,” “the,” and “at least one,” or the terms “one or more,” and similar indicators, should be interpreted to cover both the singular and the plural, unless otherwise stated herein or clearly contradicted by the context. The use of the term “at least one” following a list of one or more items (e.g., “at least one of A and B” or “one or more of A and B”) should be interpreted to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B; A, A and B; A, B and B), unless otherwise stated herein or clearly contradicted by the context. Similarly, the word “or” as used herein refers to any possible permutation of a set of items. For example, the phrase “A, B or C” refers to at least one of A, B, C or any combination thereof, such as any one of the following: A; B; C; A and B; A and C; B and C; A, B and C; or multiple items such as A and A; B, B and C; A, A, B, C and C; etc.

[0052] It will be apparent to those skilled in the art that various modifications and variations can be made to the control systems, working machines, and / or methods of this disclosure without departing from the scope of this disclosure. Other embodiments will be apparent to those skilled in the art in light of the description and practice of the control systems, working machines, and / or methods disclosed herein. The description and examples are intended to be considered exemplary only, and the true scope of this disclosure is indicated by the following claims and their equivalents.

Claims

1. A method for operating the engine of a work machine via a controller, the method comprising: Detect a request to shift the transmission of the machine from neutral to the desired starting gear; Determine the current transmission output speed of the transmission; Determine the desired transmission output speed of the transmission corresponding to the desired starting gear; The desired minimum speed of the engine is determined based on the difference between the current transmission output speed and the desired transmission output speed; as well as Based on the request to shift gears in the transmission, the engine is operated at the desired minimum speed or a speed higher than the desired minimum speed before the transmission shift from neutral to the desired starting gear is completed.

2. The method according to claim 1, further comprising: If the current transmission output speed is lower than the desired transmission output speed, then the engine minimum speed is increased from the current minimum idle speed to the desired minimum speed.

3. The method of claim 2, wherein the minimum speed is increased from the current minimum idle speed to the desired minimum speed at an increase rate proportional to the difference between the current transmission output speed and the desired transmission output speed.

4. The method according to claim 3, further comprising: The boost rate of the minimum speed is limited to below a predefined boost rate.

5. The method according to claim 3, further comprising: Once the machine begins to move from a standstill, the minimum speed of the engine is reduced from the desired minimum speed to the engine speed requested by the operator.

6. The method of claim 5, wherein the minimum speed is reduced from the desired minimum speed to the engine speed requested by the operator at a decreasing rate, and wherein the method comprises: The rate of decrease of the minimum speed is limited to below a predefined rate of decrease.

7. The method of claim 2, wherein the desired starting gear corresponds to a gear, and once the gear is engaged, the transmission load applied to the engine exceeds the torque capacity of the engine at the current minimum idle speed.

8. A working machine, the working machine comprising: engine; A transmission, operably coupled to the engine to transmit power to one or more traction devices of the working machine, thereby facilitating machine movement; and A control system for operating the engine and comprising: The controller is configured to: Detect a request for a gear shift from neutral to the desired starting gear in the transmission; Determine the current transmission output speed of the transmission; Determine the desired transmission output speed of the transmission corresponding to the desired starting gear; and The desired minimum speed of the engine is determined based on the difference between the current transmission output speed and the desired transmission output speed; and Based on the request to shift gears in the transmission, the engine is operated at the desired minimum speed or a speed higher than the desired minimum speed before the transmission shift from neutral to the desired starting gear is completed.

9. A control system for an engine used to operate a work machine, the control system comprising: The controller is configured to: Detect a request to shift the transmission of the machine from neutral to the desired starting gear; Determine the current transmission output speed of the transmission; Determine the desired transmission output speed of the transmission corresponding to the desired starting gear; The desired minimum speed of the engine is determined based on the difference between the current transmission output speed and the desired transmission output speed; as well as Based on the request to shift gears in the transmission, the engine is operated at the desired minimum speed or a speed higher than the desired minimum speed before the transmission shift from neutral to the desired starting gear is completed.

10. The control system of claim 9, wherein the controller is configured to: If the current transmission output speed is lower than the desired transmission output speed, then the engine minimum speed is increased from the current minimum idle speed to the desired minimum speed. The controller increases the minimum speed from the current minimum idle speed to the desired minimum speed at a rate proportional to the difference between the current transmission output speed and the desired transmission output speed.

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