Vehicle system

Abstract

A vehicle system includes a vehicle engine, a plurality of intake and exhaust valves coupled to the vehicle engine configured to adjust performance of the vehicle engine, and a camshaft coupled to the plurality of intake and exhaust valves and configured to control timing of the intake and exhaust valves. The vehicle system also includes a camshaft phaser configured to adjust a position of the engine camshaft. Further, the vehicle system includes a vehicle processor. The vehicle processor is configured to store data including vehicle data and apply an increased oil pressure to the camshaft phaser based on the vehicle data such that the oil pressure increases within a predetermined range of vehicle data in which the camshaft phaser is unstable to prevent future camshaft position instability.

Description

[0001] introduction

[0002] The information provided in this section is for the purpose of generally presenting the context of the present disclosure. The work of the presently named inventors, to the extent described in this section, and in aspects of the description that may not otherwise be considered prior art at the time of filing, is neither explicitly nor implicitly admitted to be prior art against the present disclosure. Technical Field

[0003] The present disclosure relates generally to a vehicle system, and more particularly to a vehicle system having a vehicle engine. Background Art

[0004] A vehicle engine is a major component of a vehicle. A vehicle engine is configured to convert chemical energy from a fuel into mechanical energy that helps to power the engine, and thus the vehicle. A vehicle engine includes various components, including one or more camshafts configured to operate a plurality of valves, including intake and exhaust valves. The movement of the camshafts corresponds to the opening and closing of the valves. Therefore, the camshaft position determines when the intake or exhaust valves open and close, and is a key factor in the amount of power produced by the vehicle engine. During operation, a particular camshaft position may increase power at high engine speeds, but may result in less torque being produced at low engine speeds.

[0005] In addition, the vehicle engine includes one or more camshaft phasers configured to adjust the position of the camshaft. During some vehicle engine operations, including a combination of high or medium engine speeds and low torque requirements, the camshaft phasers may become unstable, resulting in reduced vehicle performance. A system is needed to address this instability. Summary of the invention

[0006] In one configuration, a vehicle system includes a vehicle engine and a plurality of intake and exhaust valves coupled to the vehicle engine and configured to adjust performance of the vehicle engine. The vehicle system also includes a camshaft coupled to the plurality of intake and exhaust valves and configured to control timing of the intake and exhaust valves. Additionally, the vehicle system includes a camshaft phaser configured to adjust a position of the camshaft. The vehicle system also includes a vehicle processor. The vehicle processor is configured to store data including vehicle data and apply increased oil pressure to the camshaft phaser based on the vehicle data such that the oil pressure increases within a predetermined vehicle data range where the camshaft phaser is unstable to prevent future camshaft position instability.

[0007] The vehicle system may also include one or more of the following optional features. For example, the vehicle data may include data related to engine load such that oil pressure increases as engine load decreases. Additionally, the boundaries of a predetermined vehicle data range may be consistently updated based on the vehicle data. The vehicle processor may also be configured to compare a current camshaft position to a predetermined desired camshaft position and apply increased oil pressure based on the vehicle data or if the current camshaft position and the desired camshaft position have a difference greater than a predetermined error amount. Additionally, the vehicle may include a vehicle system.

[0008] In another configuration, a vehicle engine system includes a vehicle processor configured to store data including vehicle data and camshaft data. Additionally, the vehicle processor is configured to determine whether a camshaft phaser is within a predetermined instability range based on one or more of the vehicle data and the camshaft data. Additionally, the vehicle processor is further configured to apply an incremental oil pressure increase to the camshaft phaser to prevent future instability if the camshaft phaser is determined to be within the predetermined instability range.

[0009] The vehicle system may also include one or more of the following optional features. For example, the incremental oil pressure increase may be a single maximum oil pressure increase. Additionally, the predetermined instability range may be continuously updated based on vehicle data feedback, the vehicle data feedback including one or more of: a camshaft peak-to-peak camshaft position error measured over a time period, a camshaft position bank-to-bank correlation, a camshaft position peak-to-peak amplitude, a camshaft position error greater than a threshold, and a filtered position value minus an instantaneous position value greater than a threshold. The vehicle processor may also be configured to determine a diagnostic value based on one or more of the vehicle feedback, the vehicle feedback including one or more of: a camshaft peak-to-peak camshaft position error measured over a time period, a camshaft position bank-to-bank correlation, a camshaft position peak-to-peak amplitude, a camshaft position error greater than a threshold, and a filtered position value minus an instantaneous position value greater than a threshold. Additionally, the vehicle processor may be configured to identify a camshaft phaser error condition if it is determined that the diagnostic value is greater than a predetermined value, such that the vehicle processor is configured to re-evaluate whether the camshaft phaser is within the predetermined instability range after a predetermined amount of time before applying the incremental oil pressure increase. Furthermore, the incremental oil pressure increases may continue until the camshaft phaser no longer exceeds a predetermined instability range. Additionally, the incremental oil pressure increases are learned and stored in the vehicle processor such that the incremental oil pressure increases may be implemented whenever the vehicle is operating in an unstable region based on vehicle data, regardless of the phaser instability criteria. Additionally, the vehicle may include a vehicle system.

[0010] In another configuration, a vehicle system includes a vehicle processor configured to store data including vehicle data and determine whether a camshaft phaser is within a predetermined unstable region based on the vehicle data. Additionally, the vehicle processor is configured to command a predetermined increased oil pressure from an oil pump and override one or more feedback loops from the oil pump to maintain the increased oil pressure from the oil pump.

[0011] The vehicle system may also include one or more of the following optional features. For example, one or more feedback loops are one or more of a proportional feedback loop, an integral feedback loop, or a differential feedback loop. In addition, the predetermined unstable range may be continuously updated based on vehicle data feedback. The vehicle processor may also be configured to store a vehicle mode, and the determination of whether the camshaft phaser is within a predetermined unstable region may also be based on the vehicle mode. In addition, the predetermined increase in oil pressure from the oil pump may be a maximum increase in oil pressure. Furthermore, the vehicle data may include an oil temperature of oil configured to flow through the camshaft phaser, and the increase in oil pressure or the maximum increase in oil pressure may vary based on the oil temperature. In addition, the vehicle may include a vehicle system. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings described herein are for illustrative purposes only of selected configurations and are not intended to limit the scope of the present disclosure.

[0013] Figure 1 is a perspective external view of a vehicle including a vehicle system according to the present disclosure;

[0014] Figure 2 is a perspective view of a camshaft of a vehicle system according to the present disclosure; and

[0015] Figure 3 is an exemplary operational flowchart of a vehicle system according to the present disclosure.

[0016] Corresponding reference characters indicate corresponding parts throughout the several views of the drawings. DETAILED DESCRIPTION

[0017] Example configurations will now be described more fully with reference to the accompanying drawings. Example configurations are provided so that the present disclosure will be thorough and will fully convey the scope of the present disclosure to those of ordinary skill in the art. Specific details, such as examples of specific components, devices, and methods, are set forth to provide a thorough understanding of the configurations of the present disclosure. It will be apparent to those of ordinary skill in the art that specific details need not be employed, that example configurations may be embodied in many different forms, and that the specific details and example configurations should not be construed as limiting the scope of the present disclosure.

[0018] The terms used herein are only used for the purpose of describing specific exemplary configurations and are not intended to be limiting. As used herein, the singular articles "a", "an" and "the" may also be intended to include plural forms unless the context clearly states otherwise. The terms "comprises", "comprising", "including" and "having" are inclusive and therefore specify the presence of features, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, steps, operations, elements, parts and / or groups thereof. The method steps, processes and operations described herein should not be interpreted as necessarily requiring them to be performed in the specific order discussed or shown, unless specifically identified as an execution order. Additional or alternative steps may be adopted.

[0019] When an element or layer is referred to as being "on another element or layer," "engaged to," "connected to," "attached to," or "coupled to" another element or layer, it may be directly on, directly engaged with, connected to, attached to, or coupled to another element or layer, or there may be intermediate elements or layers. Conversely, when an element is referred to as being "directly on another element or layer," "directly engaged to," "directly connected to," "directly attached to," or "directly coupled to" another element or layer, there may be no intermediate elements or layers. Other words used to describe the relationship between elements should be interpreted in a similar manner (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.). As used herein, the term "and / or" includes any and all combinations of one or more associated listed items.

[0020] The terms "first", "second", "third", etc. may be used in this article to describe various elements, components, regions, layers and / or parts. These elements, components, regions, layers and / or parts should not be limited by these terms. These terms may only be used to distinguish an element, component, region, layer or part from another region, layer or part. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply an order or sequence. Therefore, without departing from the teaching of the example configuration, the first element, component, region, layer or part discussed below may be referred to as a second element, component, region, layer or part.

[0021] In this application, including the definitions below, the term "module" may be replaced with the term "circuit". The term "module" may refer to, be part of, or include: an application specific integrated circuit (ASIC); a digital, analog, or mixed analog / digital discrete circuit; a digital, analog, or mixed analog / digital integrated circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor (shared, dedicated, or group) that executes code; a memory (shared, dedicated, or group) that stores code executed by the processor; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system on a chip.

[0022] The term "code" as used above may include software, firmware and / or microcode, and may refer to a program, a routine, a function, a class and / or an object. The term "shared processor" covers a single processor that executes some or all codes from multiple modules. The term "group processor" covers a processor that executes some or all codes from one or more modules in combination with an additional processor. The term "shared memory" covers a single memory that stores some or all codes from multiple modules. The term "group memory" covers a memory that stores some or all codes from one or more modules in combination with an additional memory. The term "memory" may be a subset of the term "computer-readable medium". The term "computer-readable medium" does not cover transient electrical signals and electromagnetic signals propagated through the medium, and therefore can be considered to be tangible and non-transient memory. Non-limiting examples of non-temporary memory include tangible computer-readable media, which include non-volatile memory, magnetic memory, and optical memory.

[0023] The apparatus and methods described in this application may be implemented in part or in whole by one or more computer programs executed by one or more processors. The computer program includes processor executable instructions stored on at least one non-transitory tangible computer readable medium. The computer program may also include and / or rely on stored data.

[0024] A software application (i.e., software resource) may refer to computer software that enables a computing device to perform tasks. In some examples, a software application may be referred to as an "application," "app," or "program." Example applications include, but are not limited to, system diagnostic applications, system management applications, system maintenance applications, word processing applications, spreadsheet applications, messaging applications, media streaming applications, social networking applications, and gaming applications.

[0025] Non-transitory memory can be a physical device used to temporarily or permanently store programs (e.g., sequences of instructions) or data (e.g., program state information) for use by a computing device. Non-transitory memory can be volatile and / or non-volatile addressable semiconductor memory. Examples of non-volatile memory include, but are not limited to, flash memory and read-only memory (ROM) / programmable read-only memory (PROM) / erasable programmable read-only memory (EPROM) / electrically erasable programmable read-only memory (EEPROM) (e.g., commonly used for firmware, such as bootloaders). Examples of volatile memory include, but are not limited to, random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), phase change memory (PCM), and disk or tape.

[0026] These computer programs (also referred to as programs, software, software applications, or code) include machine instructions for a programmable processor and may be implemented in high-level procedural and / or object-oriented programming languages ​​and / or assembly / machine languages. As used herein, the terms "machine-readable medium" and "computer-readable medium" refer to any computer program product, non-transitory computer-readable medium, apparatus, and / or device (e.g., disk, optical disk, memory, programmable logic device (PLD)) for providing machine instructions and / or data to a programmable processor, including a machine-readable medium that receives machine instructions as a machine-readable signal. The term "machine-readable signal" refers to any signal for providing machine instructions and / or data to a programmable processor.

[0027] Various implementations of the systems and techniques described herein can be implemented in digital electronic and / or optical circuits, integrated circuits, specially designed ASICs (application specific integrated circuits), computer hardware, firmware, software, and / or combinations thereof. These various implementations may include implementations in one or more computer programs executable and / or interpretable on a programmable system that includes at least one programmable processor, which may be special purpose or general purpose, coupled to receive data and instructions from a storage system, at least one input device, and at least one output device, and to send data and instructions to the storage system, at least one input device, and at least one output device.

[0028] The process and logic flow described in this specification can be performed by one or more programmable processors (also referred to as data processing hardware), which execute one or more computer programs to perform functions by operating on input data and generating output. The process and logic flow can also be performed by a dedicated logic circuit (e.g., FPGA (field programmable gate array) or ASIC (application-specific integrated circuit)). As an example, a processor suitable for executing a computer program includes both general-purpose and special-purpose microprocessors, and any one or more processors of any type of digital computer. Typically, the processor will receive instructions and data from a read-only memory or a random access memory or both. The basic elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Typically, a computer will also include one or more mass storage devices (e.g., magnetic disks, magneto-optical disks, or optical disks) for storing data, or be operably connected to receive data from it or transmit data to it or both. However, a computer does not need to have such a device. Computer-readable media suitable for storing computer program instructions and data include all forms of nonvolatile memory, media, and memory devices, including, for example, semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD ROM and DVD-ROM disks. The processor and memory may be supplemented by, or incorporated in, special purpose logic circuitry.

[0029] To provide interaction with a user, one or more aspects of the present disclosure may be implemented on a computer having a display device (e.g., a CRT (cathode ray tube), LCD (liquid crystal display) monitor, or touch screen) for displaying information to the user and optionally a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other kinds of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback, such as visual feedback, auditory feedback, or tactile feedback; and input from the user may be received in any form, including sound, voice, or tactile input. In addition, the computer may interact with the user by sending documents to and receiving documents from a device used by the user; for example, by sending a web page to a web browser on a user's client device in response to a request received from the web browser.

[0030] Now refer to Figures 1 to 3 In the example shown in FIG. 1 , a vehicle system is shown at reference numeral 10 . In some examples, such as Figure 1In the example shown in , the vehicle system 10 is incorporated into a vehicle 12. The vehicle 12 can be a hybrid electric vehicle (HEV) that includes electric vehicle (EV) and internal combustion engine (ICE) components and capabilities, or can include only ICE components and capabilities. Although the vehicle 12 can be a HEV, the vehicle 12 will be described as including only ICE components and capabilities. Therefore, the vehicle 12 will be described and shown below and in the figures as including an engine 14.

[0031] The vehicle engine 14 may be an ICE and includes various components configured to provide various operations requiring power for the vehicle 12. For example, the vehicle engine 14 may be an eight-cylinder ICE (V8) having two groups (a first group and a second group) of four cylinders, wherein each of the two groups shares a common crankshaft (not shown). The vehicle engine 14 also includes various other components, including one or more camshafts 16 and a camshaft phaser 18, wherein the one or more camshafts 16 are configured to operate a plurality of valves (not shown), including intake valves and exhaust valves. In addition, the intake valves and exhaust valves are configured to adjust the performance of the vehicle engine 14. More specifically, the movement of the camshaft 16 corresponds to the opening and closing of the intake valves and the exhaust valves, which affects the oil pressure within the vehicle system 10. Therefore, the position of the camshaft 16 determines the opening and closing timing of the intake valves and / or the exhaust valves, and is a key factor in the amount of power generated by the vehicle engine 14. For example, a particular position of the camshaft 16 may increase power at high engine speeds, but may result in less torque being generated at low engine speeds. Although the vehicle engine 14 may include one or more camshafts 16 and associated phasers 18 , the vehicle engine 14 will be described and illustrated hereinafter as including two (2) camshafts 16 and associated phasers 18 .

[0032] like Figure 1 and Figure 2 As best shown in FIG. 1 , the vehicle engine 14 includes a camshaft phaser 18 attached to the camshaft 16. The camshaft phaser 18 is configured to adjust the rotational position of the camshaft 16 based on commands from the vehicle processor 200 to adjust the performance of the vehicle engine 14. In the example shown, the camshaft phaser 18 is one or more hydraulic actuators configured to electromechanically adjust the position of the camshaft 16, however, various other configurations are also contemplated, including fully mechanical or fully electrical configurations.

[0033] The camshaft phaser 18 relies on engine oil pressure to operate. The oil can originate from an oil pump coupled to the vehicle engine 14, or from another source as desired. In addition, the oil pump can be a variable control oil pump or other oil storage device commanded by the vehicle processor 200. In addition, the oil pump can be controlled using typical proportional-integral-derivative (PID) control.

[0034] During some vehicle engine operations, including combinations of high or medium engine speeds and low torque demands, the camshaft phaser 18 may become unstable, resulting in performance issues with the vehicle 12. The vehicle system 10 as described herein is configured to prevent camshaft phaser 18 instability. However, if camshaft instability occurs, the vehicle system 10 is configured to quickly detect the instability and make adjustments to one or more of the camshafts 16 via the camshaft phaser 18 to correct the instability.

[0035] The vehicle system 10 also includes a vehicle processor 200, which is configured to store data and control the movement of the camshaft phaser 18. The vehicle processor 200 can be an engine control unit (ECU) or other vehicle controller. In addition, the vehicle processor 200 is configured to store data including vehicle data 202 and camshaft data 204. The vehicle data 202 includes one or more of oil temperature and / or pressure, vehicle speed, vehicle torque, and vehicle mode. The oil temperature and / or pressure is generally related to the current temperature and / or pressure of the oil flowing through the camshaft phaser 18. The oil temperature and / or pressure can be determined by a sensor (not shown) within the system, or can be measured or obtained from another source. In some examples, the oil temperature and / or pressure can be constantly changing so that the temperature and / or pressure of the oil can be continuously sensed and / or obtained during vehicle operation.

[0036] The vehicle speed is generally related to the current speed of the vehicle 12. The vehicle speed may be obtained, sensed, measured and / or calculated from one or more vehicle sensors 22 and / or cameras 24. Additionally or alternatively, the vehicle speed is generally related to the speed of the vehicle engine 14. More specifically, the vehicle engine speed may be expressed as "revolutions per minute" or RPM, and represents the number of times the crankshaft of the vehicle engine 14 makes a complete rotation every 60 seconds. Additionally, in addition to being stored in the vehicle processor 200, the RPM may also be displayed on the vehicle instrument panel. Furthermore, the vehicle speed may be constantly changing, such that the vehicle speed may be continuously sensed and / or obtained during vehicle operation.

[0037] The vehicle torque is generally related to the amount of power produced by the vehicle engine 14. The vehicle torque may be measured, sensed, or obtained by various vehicle sensors 22 or other devices. The vehicle torque may be related to the current amount of torque produced by the vehicle engine 14. Additionally or alternatively, the vehicle torque may be related to the desired amount of torque. Furthermore, it is also contemplated that the vehicle torque may be additionally or alternatively related to the difference between the current amount of torque produced and the desired amount of torque.

[0038] The vehicle mode generally refers to the mode of the vehicle. The vehicle mode includes, but is not limited to, a performance mode, a thermal mode, and / or a normal driving mode. The vehicle mode may be measured, sensed, or obtained by various vehicle sensors 22, or determined by the vehicle processor 200.

[0039] The camshaft data 204 generally relates to specific data related to the camshaft 16. For example, the camshaft data 204 may include the current position of the camshaft 16. The current position of the camshaft 16 is generally related to the position at which the camshaft 16 is currently located. The position may be measured, sensed, or otherwise obtained from the vehicle sensor 22 and / or the vehicle processor 200 in the vehicle 12. Additionally or alternatively, the camshaft data 204 may also include the desired position of the camshaft 16, which may also be measured, sensed, or otherwise obtained. In addition, the desired position of the camshaft 16 may be predetermined based on the vehicle data 202 or other information. For example, a predetermined desired camshaft position may be calculated or determined based on the vehicle engine speed and the vehicle engine load. Additionally or alternatively, the camshaft data 204 may also include a camshaft position error, which may be calculated using the current camshaft position and the desired camshaft position. In addition, the camshaft position error may be calculated using the current camshaft position and the desired camshaft position and an offset value. The offset value may be a predetermined value and / or may be based on the vehicle data 202. Additionally or alternatively, the position of the camshaft phaser 18 may be used to calculate the camshaft position error. More specifically, the camshaft position error may be calculated using the position difference between the camshaft phaser 18 coupled to the intake valve and the camshaft phaser 18 coupled to the exhaust valve. Additionally or alternatively, the camshaft position error may be calculated using an integrated value of the position of the camshaft phaser 18 and a filtered position of the position of the camshaft phaser 18 to detect rapid camshaft phaser oscillations. In addition, the camshaft data 204 may also include data related to a camshaft peak-to-peak camshaft position error over a period of time, a camshaft peak-to-peak amplitude, and a comparison of camshaft positions between multiple groups within the vehicle engine 14.

[0040] In addition, the vehicle processor 200 is also configured to compare the current camshaft position to a predetermined desired camshaft position. In addition, if the current camshaft position is different from the desired camshaft position, the vehicle processor 200 can command an increase in oil pressure to one or more camshaft phasers 18 so that the oil pressure within the vehicle system 10 is increased, thereby providing stability to the camshaft phasers 18. The increased oil pressure can be drawn from a variable control oil pump or other oil storage device and commanded by the vehicle processor 200. In addition, the oil pump can be controlled using typical proportional-integral-derivative (PID) control. The increased oil pressure from the oil pump prevents future camshaft position instability by increasing the oil pressure before one or more of the camshaft phasers 18 become unstable.

[0041] In addition, the vehicle processor 200 can be configured to increase the oil pressure to the camshaft phaser 18 based on the vehicle data 202, including but not limited to the vehicle engine speed and the vehicle torque. The increase in oil pressure can be an increment of the increased oil pressure that occurs multiple times over a period of time. However, in some examples, the increase in oil pressure can be a single maximum oil pressure increase, so that the vehicle processor 200 commands the oil pump to increase the oil pressure to a maximum amount. In addition, if the vehicle data 202 is within a predetermined range, the increased oil pressure can be applied. The predetermined range can be based on any vehicle data 202, including but not limited to the vehicle engine speed and the vehicle torque. For example, a high engine speed and a low torque requirement can trigger an increased oil pressure. By commanding an increased oil pressure based on the vehicle data 202 within the predetermined range, the vehicle processor 200 can prevent future camshaft position instability. In addition, in order to continuously improve the boundaries of the predetermined range, the predetermined range can be consistently updated based on the updated vehicle data 202.

[0042] Still reference Figure 1-3 , the vehicle processor 200 may also be configured to determine whether the camshaft phaser 18 is operating in an unstable manner based on a predetermined instability threshold within a predetermined instability range. Determining whether one or more of the camshaft phasers 18 are unstable (i.e., within the predetermined instability range) allows the vehicle processor 200 to implement additional oil pressure before the camshaft phaser 18 reaches an instability that cannot be corrected. The determination of whether the camshaft phaser 18 is unstable (i.e., within the predetermined instability range) may be based on the vehicle data 202. The vehicle data 202 used to determine the instability of the camshaft phaser 18 may include one or more of a camshaft peak-to-peak camshaft position error over a period of time, a camshaft position correlation between groups within the engine, a camshaft peak-to-peak amplitude, and a camshaft position error. Additionally, the predetermined instability range may be associated with a high vehicle engine speed and a low engine torque.

[0043] Additionally, the instability criteria (i.e., the boundaries of the predetermined instability range) for the camshaft phaser 18 may be continuously updated based on the vehicle data 202, which includes one or more of a camshaft peak-to-peak camshaft position error over a period of time, a comparison of camshaft positions between multiple groups of the engine 14, a camshaft peak-to-peak amplitude, and a camshaft position error. For example, if it is determined that the camshaft 16 has a camshaft position error for more than a predetermined amount of time (e.g., the current camshaft position is different from the predetermined position), then it may be determined that the associated camshaft phaser 18 is unstable. In another example, if the difference between the current camshaft position near the intake valve and the current camshaft position value near the exhaust valve is greater than a predetermined value, then the camshaft phaser 18 may be determined to be within the predetermined instability range. Additionally, in another example, if the filtered camshaft phaser position minus the current camshaft position is greater than a predetermined value, then it may be determined that the camshaft phaser 18 is within the instability range.

[0044] If it is determined that the camshaft phaser 18 is unstable (i.e., within a predetermined instability range), the vehicle processor 200 can be configured to apply incremental oil pressure increases to the camshaft phaser 18 to prevent further instability. However, in some examples, the incremental oil pressure increases can be a single maximum oil pressure increase if desired. The incremental oil pressure increases can continue until the camshaft phaser 18 no longer meets the criteria for being considered unstable.

[0045] In addition, the vehicle processor 200 is configured to identify or flag a camshaft phaser error condition if it is determined that the camshaft phaser 18 is within a predetermined unstable range. This flag allows the vehicle processor 200 to closely monitor the camshaft phaser 18 and repeat the camshaft phaser error calculation after a predetermined amount of time to verify instability. The increase in oil pressure may be activated only when the number of flags exceeds a predetermined threshold. However, it is also contemplated that the increase in oil pressure may be activated after a single flag, if desired.

[0046] In addition, the vehicle processor 200 can be configured to determine a diagnostic value based on one or more of the feedback of the vehicle data 202, the vehicle data 202 including one or more of a measured camshaft peak-to-peak position error over a period of time, a correlation of camshaft positions between multiple engine groups, a camshaft peak-to-peak amplitude, a camshaft position error greater than a threshold, and a filtered position value minus an instantaneous position value greater than a threshold. In addition, the vehicle processor 200 is further configured to flag a camshaft phaser error condition if the diagnostic value is determined to be greater than a predetermined value. As described above, the flag allows the vehicle processor 200 to closely monitor the camshaft phaser 18 and repeat the calculation of whether the camshaft phaser 18 is within a predetermined unstable range after a predetermined amount of time before applying an incremental oil pressure increase. The diagnostic value can also be used by the vehicle processor 200 or other vehicle systems to diagnose vehicle engine problems or other related problems.

[0047] In addition, the predetermined unstable range may be affected by the oil temperature. More specifically, if the oil temperature is above a predetermined threshold, an increase in oil pressure may not be commanded to prevent damage to the vehicle system 10. However, in some examples, if the oil temperature is below a certain threshold, the amount of increased oil pressure may be adjusted to account for the oil temperature. The predetermined threshold temperature may be a known value, or may be calculated and / or determined based on the vehicle data 202. In addition, whether the increase in oil pressure is incremental or a maximum increase may be based on the oil temperature. For example, if a maximum increase is desired but the oil temperature is too cold to produce a maximum increase, the increase in oil pressure may instead be determined as an incremental increase.

[0048] In addition, the vehicle processor 200 can also be configured to maintain increased oil pressure by overriding one or more feedback loops from the oil pump. For example, the vehicle processor 200 can be configured to override an integral feedback loop. In other examples, the vehicle processor 200 is configured to override a proportional feedback loop. In other examples, the vehicle processor 200 is configured to override a differential feedback loop. In addition, in other examples, the vehicle processor 200 can also be configured to override more than one of an integral feedback loop, a proportional feedback loop, and a differential feedback loop. In addition, if the oil temperature is above a predetermined threshold temperature, the override of one or more feedback loops can be commanded only by the vehicle processor 200.

[0049] In some examples, the amount of increase in oil pressure may also be based on the vehicle mode. For example, if the vehicle 12 is in a performance mode, the amount of increase in oil pressure required may be different than the amount of increase in oil pressure in a conventional driving mode. In another example, if the vehicle 12 is in a heat mode, such that the vehicle 12 determines that the weather is very hot and adjusts accordingly, the amount of increase in oil pressure required may be different than the amount of increase in oil pressure in a conventional driving mode.

[0050] Reference now Figure 3 In the example shown in FIG. 1 , in operation, the vehicle 12 is operated at normal oil pressure using normal control at step 500. The vehicle processor 200 performs calculations at step 502 using the vehicle data 202, which includes the camshaft positions of the intake camshaft 16 and the exhaust camshaft 16 on the first group of the engine at 504, the camshaft positions of the intake camshaft 16 and the exhaust camshaft 16 on the second group at 506, and the desired camshaft position at 508. The calculations may include one or more of the calculation of the camshaft peak-to-peak position error over a period of time, the comparison of the camshaft positions between multiple engine groups, and the camshaft peak-to-peak amplitude. Other calculations shown here include subtracting the desired camshaft position and the current camshaft position at step 510, and comparing the camshaft positions at step 512. The vehicle processor 200 inputs the vehicle engine speed and engine torque at step 513, and determines at step 514 whether any calculation is found to exceed a predetermined threshold. In addition, at step 516, the vehicle processor 200 determines whether the camshaft phaser 18 is within a predetermined unstable range. If any predetermined threshold is exceeded and / or if the camshaft phaser 18 is within a predetermined unstable range, then at step 518, the oil pressure may be incrementally increased to prevent future camshaft phaser instabilities. Additionally, at step 520, the oil pump duty cycle may be set to a calibrated value. Then, at step 524, an adjustment value may be applied to the oil pump based on the oil temperature. Additionally, the vehicle processor 200 may freeze or reset one or more of the integral feedback loop or the proportional feedback loop at step 522. The vehicle processor 200 continues steps 518, 520, 522, and 524 until the calculation is below a predetermined threshold and / or outside the unstable range.

[0051] During some vehicle engine operations, including a combination of high or medium vehicle engine speeds and low torque demands, the camshaft phaser 18 may become unstable, resulting in vehicle performance issues. The vehicle system 10 as described herein is configured to prevent camshaft phaser instability altogether by incrementally increasing oil pressure when the difference between the current camshaft position and the desired camshaft position is above a predetermined threshold. In addition, the vehicle system 10 as described herein is configured to quickly detect camshaft phaser instability before the camshaft phaser instability becomes unrecoverable by increasing oil pressure when the camshaft phaser 18 is determined to be within a predetermined instability range. By preventing and / or diagnosing and reversing camshaft phaser instability, oil pressure can be maintained at a lower oil pressure value during normal operation. This results in a number of benefits, including fuel economy, lower thermal shock, lower oil aeration, more oil volume retained in the oil tank for a dry sump system, and improved oil pump life.

[0052] Many embodiments have been described. However, it should be understood that various modifications can be made without departing from the spirit and scope of the present disclosure. Therefore, other embodiments are within the scope of the appended claims.

[0053] The foregoing description is provided for the purpose of illustration and description. It is not intended to be exhaustive or to limit the present disclosure. The individual elements or features of a particular configuration are generally not limited to that particular configuration, but are interchangeable where applicable and can be used in a selected configuration, even if not specifically shown or described. It can also be varied in many ways. Such variations should not be considered as departing from the present disclosure, and all such modifications are intended to be included within the scope of the present disclosure.

Claims

1. A vehicle system, comprising: a vehicle engine including a camshaft phaser configured to adjust performance of the vehicle engine; as well as A vehicle processor configured to: storing data including vehicle data; as well as Increased oil pressure is applied to the camshaft phaser based on the vehicle data such that the oil pressure is increased within a predetermined vehicle data range where the camshaft phaser is unstable to prevent future camshaft position instabilities. 2 . The vehicle system of claim 1 , wherein the vehicle data includes data related to engine load, such that the oil pressure increases as the engine load decreases. 3 . The vehicle system of claim 1 , wherein the boundaries of the predetermined vehicle data range are consistently updated based on the vehicle data.

4. The vehicle system of claim 1 , wherein the vehicle processor is further configured to compare a current camshaft position to a predetermined desired camshaft position and apply increased oil pressure based on vehicle data if the current camshaft position and the desired camshaft position have a difference greater than a predetermined error amount.

5. The vehicle system of claim 1 wherein the increased oil pressure is a plurality of incremental oil pressure increases.

6. The vehicle system of claim 1, wherein the increased oil pressure is a single maximum increase in oil pressure. 7 . The vehicle system of claim 1 , further comprising an oil pump, and the server is configured to override one or more feedback loops from the oil pump to maintain increased oil pressure from the oil pump.

8. The vehicle system of claim 1 , wherein the vehicle processor is configured to determine a diagnostic value based on feedback from the vehicle data, the vehicle data comprising one or more of: a camshaft position error peak-to-peak amplitude measured over a period of time, a comparison of camshaft positions between multiple groups within a vehicle engine, a camshaft peak-to-peak amplitude, a camshaft position error greater than a threshold, and a filtered position value minus an instantaneous position value greater than a threshold.

9. The vehicle system of claim 1 , wherein the vehicle processor is configured to determine whether a camshaft phaser is within a predetermined instability range based on vehicle data, and to continuously update the predetermined instability range based on vehicle data feedback including one or more phaser instability criteria, the phaser instability criteria including a camshaft position error peak-to-peak amplitude measured over a period of time, a comparison of camshaft positions between a plurality of groups within a vehicle engine, a camshaft peak-to-peak amplitude, a camshaft position error greater than a threshold, and a filtered position value minus an instantaneous position value greater than a threshold.

10. A vehicle comprising the vehicle system according to claim 1.

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