Switching control method, device, terminal and medium for valve lift

Abstract

The application belongs to the technical field of automobile control, and particularly relates to a valve lift switching control method and device, a terminal and a medium. The valve lift switching control method comprises the following steps: acquiring an advance energization angle, wherein the advance energization angle is a first preset angle determined according to the response time of an electromagnetic valve; if the advance energization angle is less than an energization angle threshold, sending a pin extension instruction to the electromagnetic valve when the crank angle of the engine reaches the advance energization angle, wherein the pin extension instruction is used to instruct the electromagnetic valve to extend a pin, so that the pin cooperates with a valve switching drive device to realize valve lift switching. The application sends the pin extension instruction to the electromagnetic valve when the crank angle of the engine reaches the advance energization angle, which can control the electromagnetic valve to extend the pin for valve lift switching earlier, and does not need to compensate for the response delay characteristics of the electromagnetic valve by reducing the limit allowable speed of the engine crank, thereby improving the performance of the engine.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to a valve lift switching control method, device, terminal, and medium. Background Technology

[0002] Variable valve lift technology matches the appropriate valve lift at different engine speeds and loads. When the engine is at low speed and light load, a smaller valve lift is used, which helps save fuel. When the engine is at high speed and heavy load, a larger valve lift is used, which reduces valve throttling losses, significantly increases intake volume, and enhances power performance, thus balancing engine power performance and economy.

[0003] Based on the aforementioned variable valve lift technology, the commonly used valve lift switching scheme in the industry involves using a solenoid valve to control the extension or retraction of a pin. This pin engages with a valve switching drive mechanism mounted on the camshaft sleeve of the engine, causing axial displacement of the camshaft sleeve. This allows different cams corresponding to different valve lifts to mate with the valves, ultimately achieving valve lift switching. However, to ensure smooth valve lift switching within the common base circle angle of the cams mate with the valves, this scheme limits the crankshaft's maximum permissible speed, thus restricting engine performance.

[0004] Therefore, how to optimize the valve lift switching process to improve engine performance is a pressing problem that needs to be solved in the field of mechanical control technology. Summary of the Invention

[0005] The main objective of this invention is to provide a valve lift switching control method, device, terminal, and medium, which aims to improve engine performance by optimizing the valve lift switching process at the software control level.

[0006] According to one aspect of the embodiments of this application, a valve lift switching control method is disclosed, including:

[0007] The advance energizing angle is obtained, which is a first preset angle determined based on the response time of the solenoid valve;

[0008] If the advance energizing angle is less than the energizing angle threshold, when the crankshaft angle of the engine reaches the advance energizing angle, a pin extension command is sent to the solenoid valve. The pin extension command is used to instruct the solenoid valve to extend the pin so that the pin cooperates with the valve switching drive device to achieve valve lift switching.

[0009] In some embodiments of this application, based on the above technical solutions, obtaining the advance energization angle includes:

[0010] If the required valve lift does not match the current valve lift, a lift switching command is triggered;

[0011] The current system operating parameters are detected according to the lift switching command, and the response time of the solenoid valve is obtained according to the system operating parameters.

[0012] The current engine speed is obtained, and the advance energizing angle is calculated based on the engine speed and the response time.

[0013] In some embodiments of this application, based on the above technical solutions, before triggering a lift switching command if the required valve lift does not match the current valve lift, the switching control method further includes:

[0014] The changes in the state parameters fed back by the solenoid valve are obtained, wherein different position states of the pin correspond to different state parameters;

[0015] The position state of the pin is determined based on the changes in the state parameters;

[0016] The current valve lift is determined based on the position of the pin.

[0017] In some embodiments of this application, based on the above technical solutions, the energizing angle threshold is the first rotation angle value corresponding to the rotation cycle of the engine crankshaft. If the advance energizing angle is less than the energizing angle threshold, before sending the pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle, the switching control method further includes:

[0018] The pre-energization angle is compared with the first rotation angle value.

[0019] In some embodiments of this application, based on the above technical solutions, after sending a pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle if the advance energizing angle is less than the energizing angle threshold, the switching control method further includes:

[0020] The early power-off angle is obtained, which is a second preset angle determined based on the response time of the solenoid valve. The second preset angle is different from the first preset angle.

[0021] If the advance power-off angle reaches the power-off angle threshold, when the crankshaft angle of the engine reaches the advance power-off angle, a pin retraction command is sent to the solenoid valve. The pin retraction command is used to instruct the solenoid valve to retract the pin.

[0022] In some embodiments of this application, based on the above technical solutions, if the early power-off angle reaches the power-off angle threshold, when the crankshaft angle of the engine reaches the early power-off angle, a pin retraction command is sent to the solenoid valve, including:

[0023] The preset proportion of the target axial displacement required for the engine cam sleeve to complete the valve lift switching is obtained, and the second rotation angle value of the engine crankshaft is obtained accordingly.

[0024] The third rotation angle value of the engine crankshaft is obtained according to the system operating parameters when the pin separates from the valve switching drive device during the valve lift switching process.

[0025] The power-off angle threshold is determined within a numerical range greater than the second rotation angle value and the third rotation angle value.

[0026] If the pre-cut-off angle reaches the pre-cut-off angle threshold, a pin retraction command is sent to the solenoid valve when the crankshaft angle of the engine reaches the pre-cut-off angle.

[0027] In some embodiments of this application, based on the above technical solutions, before obtaining the advance energization angle, the switching control method further includes:

[0028] Obtain the extreme value of the energizing angle used to control the extension pin of the solenoid valve, wherein the extreme value of the energizing angle is the maximum or minimum energizing angle corresponding to the valve lift switching that enables the extension pin of the solenoid valve to be switched.

[0029] The energizing angle range is generated based on the extreme values ​​of the energizing angle.

[0030] The advance energizing angle is determined within the energizing angle range; and / or,

[0031] Obtain the extreme value of the de-energizing angle for controlling the retraction pin of the solenoid valve, wherein the extreme value of the de-energizing angle is the maximum or minimum de-energizing angle corresponding to the valve lift switching that enables the retraction pin of the solenoid valve to be controlled.

[0032] The power-off angle range is generated based on the extreme values ​​of the power-off angle.

[0033] The early power-off angle is determined within the range of power-off angles.

[0034] According to one aspect of the embodiments of this application, a valve lift switching control device is disclosed, the valve lift switching control device comprising:

[0035] The acquisition module is configured to acquire the advance energization angle, which is a first preset angle determined based on the response time of the solenoid valve.

[0036] The sending module is configured to send a pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle if the advance energizing angle is less than the energizing angle threshold. The pin extension command is used to instruct the solenoid valve to extend the pin so that the pin cooperates with the valve switching drive device to realize valve lift switching.

[0037] According to one aspect of the embodiments of this application, an electronic device is provided, the electronic device comprising: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to perform a valve lift switching control method as described above by executing the executable instructions.

[0038] According to one aspect of the embodiments of this application, a computer program product or computer program is provided, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the valve lift switching control method as described in the above technical solutions.

[0039] The valve lift switching control method provided in this application, when it is necessary to switch the valve lift, such as switching from high lift to low lift, or from low lift to high lift, obtains an advance energizing angle. This advance energizing angle is a first preset angle determined based on the response time of the solenoid valve. Therefore, this advance energizing angle is less than the actual crankshaft angle of the engine when the solenoid valve control pin extends. The advance energizing angle is compared with an energizing angle threshold. If the advance energizing angle is less than the energizing angle threshold, it indicates that the advance energizing angle is feasible. When the crankshaft angle of the engine reaches the advance energizing angle, a pin extension command is sent to the solenoid valve. The pin extension command is used to instruct the solenoid valve to extend the pin. The pin cooperates with the valve switching drive device provided on the cam sleeve of the engine, thereby driving the cam sleeve to perform axial displacement, so that the different cams corresponding to different valve lifts are connected to the valves, and finally the valve lift switching is realized.

[0040] Thus, the valve lift switching control method provided in this application sends a pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle. Compared with the conventional solution, the energizing angle for controlling pin extension is smaller, which means that the solenoid valve can extend the pin to switch valve lift earlier. This effectively addresses the response lag characteristic of the solenoid valve and maximizes the utilization of the common base circle angle of the cam that interfaces with the valve. It eliminates the need to reduce the maximum allowable speed of the engine crankshaft to compensate for the response lag characteristic of the solenoid valve, thereby improving engine performance.

[0041] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0042] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0043] Figure 1 A schematic diagram of a valve lift switching device according to one embodiment of this application is shown. Figure 1 'a' indicates that the system is in a low lift state. Figure 1 b indicates the system is in a high-lift state; 1 is the ECU electronic controller unit; 2 is the solenoid valve; 2-1 is the left pin of the solenoid valve; 2-2 is the right pin of the solenoid valve; 3 is the cam sleeve; 3-1 is the valve switching drive device; 3-2 is the high-lift cam; 3-3 is the low-lift cam; 4 is the cam spindle; 5 is the engine valve.

[0044] Figure 2 A flowchart illustrating the steps of a valve lift switching control method according to one embodiment of this application is shown.

[0045] Figure 3 The diagram illustrates the displacement of the solenoid valve pin under different system operating parameters in one embodiment of this application.

[0046] Figure 4 The diagram shows a curve illustrating the change in contact force on the cam sleeve during valve lift switching according to an embodiment of this application.

[0047] Figure 5 This illustration shows a time diagram of optimizing the valve lift switching process based on the advance power-on time and advance power-off time in one embodiment of this application.

[0048] Figure 6 A schematic diagram of the forces acting on the cam sleeve in one embodiment of this application is shown, wherein 6 is the thrust steel ball and 7 is the thrust spring.

[0049] Figure 7 A flowchart illustrating the application of the valve lift switching control method in one embodiment of this application is shown.

[0050] Figure 8 A schematic block diagram of the valve lift switching control device provided in an embodiment of this application is shown.

[0051] Figure 9A schematic diagram of a computer system architecture suitable for implementing the embodiments of this application is shown. Detailed Implementation

[0052] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0053] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0054] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0055] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily need to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0056] Figure 1 A schematic diagram of a valve lift switching device according to one embodiment of this application is shown. The ECU (Electronic Control Unit) 1 is connected to the solenoid valve 2 and is used to send pin extension and pin retraction commands to the solenoid valve 2. The solenoid valve 2 has a left pin 2-1 and a right pin 2-2 for cooperating with the valve switching drive device 3-1. The left pin 2-1 drives the cam sleeve 3 to move axially to the right, so that the low-lift cam 3-3 connected to the cam sleeve 3 engages with the engine valve 5, thereby allowing the engine to enter the following position: Figure 1 As shown in Figure a, the low-lift stage is achieved by the right pin 2-2 driving the cam sleeve 3 to move axially to the left, so that the high-lift cam 3-2 connected to the cam sleeve 3 engages with the engine valve 5, thereby allowing the engine to enter the low-lift stage. Figure 1 The low lift phase is shown in b.

[0057] The following detailed description of the valve lift switching control method, device, terminal, and medium provided in this application, in conjunction with specific embodiments, provides a detailed explanation of the technical solutions.

[0058] Figure 2 A flowchart illustrating the steps of a valve lift switching control method according to one embodiment of this application is shown, as follows: Figure 2 As shown, the valve lift switching control method can mainly include the following steps S100 and S200.

[0059] Step S100: Obtain the advance energizing angle, which is a first preset angle determined based on the response time of the solenoid valve.

[0060] Step S200: If the advance energizing angle is less than the energizing angle threshold, when the crankshaft angle of the engine reaches the advance energizing angle, a pin extension command is sent to the solenoid valve. The pin extension command is used to instruct the solenoid valve to extend the pin so that the pin cooperates with the valve switching drive device to achieve valve lift switching.

[0061] The valve lift switching control method provided in this application, when it is necessary to switch the valve lift, such as switching from high lift to low lift, or from low lift to high lift, obtains an advance energizing angle. This advance energizing angle is a first preset angle determined based on the response time of the solenoid valve. Therefore, this advance energizing angle is less than the actual crankshaft angle of the engine when the solenoid valve control pin extends. The advance energizing angle is compared with an energizing angle threshold. If the advance energizing angle is less than the energizing angle threshold, it indicates that the advance energizing angle is feasible. When the crankshaft angle of the engine reaches the advance energizing angle, a pin extension command is sent to the solenoid valve. The pin extension command is used to instruct the solenoid valve to extend the pin. The pin cooperates with the valve switching drive device provided on the cam sleeve of the engine, thereby driving the cam sleeve to perform axial displacement, so that the different cams corresponding to different valve lifts are connected to the valves, and finally the valve lift switching is realized.

[0062] Thus, the valve lift switching control method provided in this application sends a pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle. Compared with the conventional solution, the energizing angle for controlling pin extension is smaller, which means that the solenoid valve can extend the pin to switch valve lift earlier. This effectively addresses the response lag characteristic of the solenoid valve and maximizes the utilization of the common base circle angle of the cam that interfaces with the valve. It eliminates the need to reduce the maximum allowable speed of the engine crankshaft to compensate for the response lag characteristic of the solenoid valve, thereby improving engine performance.

[0063] The following sections will provide a detailed explanation of each step in the valve lift switching control method.

[0064] Step S100: Obtain the advance energizing angle, which is a first preset angle determined based on the response time of the solenoid valve.

[0065] Specifically, in this embodiment, since the advance energizing angle is smaller than the energizing angle in the conventional valve lift switching process, that is, the time for issuing the pin extension command to the solenoid valve is earlier, in order to cope with the response hysteresis characteristics of the solenoid valve, the advance energizing angle needs to be calculated based on the response time of the solenoid valve.

[0066] Step S200: If the advance energizing angle is less than the energizing angle threshold, when the crankshaft angle of the engine reaches the advance energizing angle, a pin extension command is sent to the solenoid valve. The pin extension command is used to instruct the solenoid valve to extend the pin so that the pin cooperates with the valve switching drive device to achieve valve lift switching.

[0067] Specifically, after obtaining the advance energizing angle for sending the pin extension command to the solenoid valve, the advance energizing angle is compared with a pre-set energizing judgment threshold to determine whether the advance energizing angle is usable. If the advance energizing angle is less than the energizing angle threshold, it proves that the advance energizing angle is usable. When the crankshaft angle of the engine reaches the advance energizing angle, the pin extension command is sent to the solenoid valve. After receiving the pin extension command, the solenoid valve controls the pin to extend after a response time. The pin cooperates with the valve switching drive device located on the cam sleeve of the engine, thereby driving the cam sleeve to perform axial displacement, so that different cams corresponding to different valve lifts are connected to the valves, and finally the valve lift switching is realized.

[0068] Furthermore, based on the above embodiments, obtaining the advance power-on angle in step S100 includes the following steps S101 to S103.

[0069] Step S101: If the required valve lift does not match the current valve lift, a lift switching command is triggered.

[0070] When a user-selected required valve lift is detected, or when the system automatically selects a required valve lift that does not match the current valve lift, a lift switching command is triggered to initiate the valve lift switching process.

[0071] Step S102: Detect the current system operating parameters according to the lift switching command, and obtain the response time of the solenoid valve according to the system operating parameters.

[0072] Specifically, because solenoid valves have a hysteresis response characteristic, and their response time changes under the influence of different system operating parameters, including voltage and oil temperature, it can be understood that the higher the voltage, the faster the solenoid valve's response speed and the shorter the response time; conversely, the higher the oil temperature, the slower the solenoid valve's response speed and the longer the response time. In practical applications, the response time of the solenoid valve corresponding to different system operating parameters can be obtained through pre-calculation or actual testing, and recorded to generate a data table. Therefore, when switching valve lift, the real-time response time of the solenoid valve can be obtained from this data table based on the real-time system operating parameters.

[0073] Step S103: Obtain the current engine speed and calculate the advance energizing angle based on the engine speed and the response time.

[0074] The current engine speed is obtained. By multiplying the engine speed by the response time of the solenoid valve, the corresponding adjustment angle can be obtained. Then, the actual crankshaft rotation angle of the engine when the solenoid valve extends the pin is subtracted from the adjustment angle to obtain the advance energizing angle used to counteract the hysteresis response characteristics of the solenoid valve.

[0075] Figure 3 This shows the time required for the pin to reach the same target displacement under system operating parameters A and B, respectively. Specifically, the solid and dashed lines represent the response curves of the solenoid valve pin under different voltage and temperature conditions, i.e., conditions A and B, respectively. T3(0) is the energizing moment, T1A is the moment the solenoid valve pin is fully extended under condition A, and T1B is the moment the solenoid valve pin is fully extended under condition B. T1A-T3 is the advance energizing time under condition A, which can be converted to crankshaft angle using δA = n / 60*360*(T1A-T3). T1B-T3 is the advance energizing time under condition B, which can also be converted to crankshaft angle using δA = n / 60*360*(T1B-T3). Figure 3 It is known that the preset parameters for the advance power-on time will change with conditions such as voltage and temperature, and need to be fitted and calibrated in advance through simulation and actual measurement data.

[0076] Thus, this embodiment provides a specific method for calculating the advance energizing angle based on the response time of the solenoid valve, so that the advance energizing angle can accurately offset the hysteresis response characteristics of the solenoid valve, thereby precisely controlling the time when the solenoid valve extends the pin during valve lift switching.

[0077] Furthermore, based on the above embodiments, before triggering the lift switching command in step S200 if the required valve lift does not match the current valve lift, the switching control method further includes the following steps S201 to S203.

[0078] Step S201: Obtain the changes in the state parameters fed back by the solenoid valve, wherein different position states of the pin correspond to different state parameters.

[0079] Specifically, the solenoid valve's feedback parameters include current and voltage. During valve lift switching, the engine's camshaft slide moves forward or backward axially in cooperation with the solenoid valve's pin and the valve switching drive device, so that the cam corresponding to different valve lifts can engage with the valve. Thus, the solenoid valve's pin includes multiple pins for driving the camshaft slide to move axially in different directions. The position state of these multiple pins, i.e., the extended state or the non-extended state, corresponds to different currents and voltages in the solenoid valve.

[0080] Step S202: Determine the position state of the pin based on the changes in the state parameters.

[0081] Specifically, based on the changes in the state parameters fed back by the solenoid valve, such as the shape of the voltage and current curves, the position state of the solenoid valve pins can be determined, such as pin A retracting from the extended state to the non-extended state, or both pin A and pin B being in the non-extended state.

[0082] Step S203: Determine the current valve lift based on the position of the pin.

[0083] After determining the position of the solenoid valve pin based on changes in the status parameters fed back by the solenoid valve, the current valve lift can be further determined based on the pin's position, since the pin can cooperate with the valve switching drive to achieve valve lift switching. For example, pin A is used to drive the camshaft sleeve to move forward axially so that the high-lift cam connected to the camshaft sleeve engages with the valve. If pin A is detected to be in an extended state, the current valve lift is determined to be high lift.

[0084] Thus, this embodiment provides a specific method for determining the current valve lift based on the status parameters fed back by the solenoid valve. Compared to installing a displacement sensor on the camshaft and determining the current valve lift by detecting the displacement of the camshaft, this method is less costly and difficult to implement.

[0085] Furthermore, based on the above embodiments, the energizing angle threshold is the first rotation angle value corresponding to the rotation cycle of the engine crankshaft. If the advance energizing angle in step S100 is less than the energizing angle threshold, before sending the pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle, the switching control method further includes the following step S104.

[0086] Step S104: Compare the pre-energization angle with the first rotation angle value.

[0087] Since the advance energizing angle is actually the crankshaft angle of the engine corresponding to the time when the command to extend the pin to the solenoid valve is sent earlier than usual, if this advance energizing angle cannot be less than the first rotation angle value corresponding to the rotation cycle of the engine crankshaft, i.e., 720°CA, it means that the valve lift switching corresponding to this advance energizing angle cannot be completed within one rotation cycle of the engine crankshaft. Therefore, the effect of "sending the command to the solenoid valve in advance - controlling the solenoid valve to extend the pin in advance" cannot be truly achieved, and in this case, the advance energizing angle is unusable. Based on this, the advance energizing angle is only usable when it is less than 720°CA.

[0088] Thus, this embodiment specifically limits the energizing angle threshold to ensure that the action of extending the pin by controlling the solenoid valve through early energizing is completed within the current rotation cycle of the engine crankshaft. This avoids situations where the action of extending the pin by controlling the solenoid valve cannot be completed within the current rotation cycle, thereby preventing the pin from extending in advance and causing other unexpected situations due to changes in system operating parameters in different rotation cycles.

[0089] Furthermore, based on the above embodiments, in step S200, if the advance energizing angle is less than the energizing angle threshold, after sending a pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle, the switching control method further includes the following steps S204 and S205.

[0090] Step S204: Obtain the early power-off angle, which is a second preset angle determined based on the response time of the solenoid valve. The second preset angle is different from the first preset angle.

[0091] Step S205: If the advance power-off angle reaches the power-off angle threshold, when the crankshaft angle of the engine reaches the advance power-off angle, a pin retraction command is sent to the solenoid valve. The pin retraction command is used to instruct the solenoid valve to retract the pin.

[0092] When the system controls the solenoid valve to extend the pin, the pin engages with the valve switching drive device located on the camshaft sleeve of the engine, thereby driving the camshaft sleeve to move axially. In the latter half of the valve lift switching process, the camshaft sleeve separates from the pin under the push of inertial force and internal force. At this time, the extended pin has no actual driving or guiding effect on the camshaft sleeve. Keeping the pin extended at this time will increase system energy consumption. Based on this, the early power-off angle is calculated by the response time of the solenoid valve. When the early power-off angle is less than the power-off angle threshold, the early power-off angle is usable. When the crankshaft angle of the engine reaches the early power-off angle, a pin retraction command is sent to the solenoid valve. Thus, the solenoid valve is controlled to retract the extended pin in the time period after the pin separates from the camshaft sleeve and before the valve lift switching process is completed, thereby effectively dealing with the hysteresis response characteristics of the solenoid valve and reducing system energy consumption.

[0093] Figure 4 This diagram illustrates the contact force experienced by the camshaft sleeve during valve lift switching according to an embodiment of this application. Figure 4 As shown, the solid line and the dotted line represent the axial displacement of the camshaft sleeve and the contact force generated by the left or right pin in the solenoid valve contacting the valve switching drive device on the camshaft sleeve at a certain engine speed. At time T4, the pin separates from the valve switching drive device. Therefore, after time T4, the camshaft sleeve undergoes free deceleration under the action of internal forces and is not driven by the pin. Figure 4 T2-T4 in the equation represents the advance power-off time, which can be converted into crankshaft rotation angle using δA = n / 60*360*(T2-T4).

[0094] Figure 5 This illustration shows a schematic diagram of optimized control of the valve lift switching process based on advance energization time and advance de-energization time in one embodiment of this application. Figure 5 As shown, the horizontal axis represents the crankshaft angle of the engine, and the vertical axis represents the output valve lift and the axial displacement of the camshaft sleeve. The high-lift and low-lift profiles of the engine valve output are aligned in the opening section. Since they are corresponding profiles of adjacent power cylinders, they appear at intervals of 180°CA (720°CA = 0°CA). The axial displacement of the camshaft sleeve occurs in the common base circle segment of the corresponding cylinder profiles and completes the entire displacement process before the second engine valve opening.

[0095] like Figure 5As shown, it can be understood that when controlling the solenoid valve to extend the pin, the conventional control method activates solenoid valve 2 at angle A1. Since the high-lift profile is completely closed at angle A1, switching at this time can maximize the use of the common base circle segment of the cam. However, the solenoid valve requires a hysteresis time of tens to hundreds of milliseconds from receiving the control current to fully extending the pin. Therefore, activating the solenoid valve at angle A1 may significantly delay the actual switching angle, which may waste the switching window or, in severe cases, cause the pin to fail to enter the slot, resulting in switching failure. This embodiment compensates for the hysteresis by activating the solenoid valve at angle A3 based on the hysteresis response characteristics of the solenoid valve, thereby ensuring that either the left or right pin can be fully extended at angle A1.

[0096] like Figure 5 As shown, it can be understood that when controlling the solenoid valve to retract the pin, the conventional control method would de-energize the solenoid valve at angle A2. Since the axial displacement of the cam sleeve is basically completed at angle A2, retracting either the left or right pin of the solenoid valve at this time can ensure a smooth switching process. However, according to actual testing, in the latter half of the valve lift switching stroke, the cam sleeve separates from the pin under the push of inertial force and internal forces. The pin has no actual driving or guiding effect on the cam sleeve, and keeping the pin extended at this time will only increase system energy consumption. This embodiment reduces system energy consumption by de-energizing the solenoid valve at angle A4 according to the system dynamics characteristics.

[0097] Furthermore, based on the above embodiments, if the advance power-off angle reaches the power-off angle threshold in step S205, a pin retraction command is sent to the solenoid valve when the crankshaft angle of the engine reaches the advance power-off angle, including the following steps S2051 to S2054.

[0098] Step S2051: Obtain the preset proportion of the target axial displacement required for the engine cam sleeve to complete the valve lift switching, and the second rotation angle value corresponding to the engine crankshaft.

[0099] Step S2052: Obtain the third rotation angle value of the engine crankshaft when the pin separates from the valve switching drive device during the valve lift switching process, based on the system operating parameters.

[0100] Step S2053: Determine the power-off angle threshold within a numerical range greater than the second rotation angle value and the third rotation angle value.

[0101] Step S2054: If the early power-off angle reaches the power-off angle threshold, when the crankshaft angle of the engine reaches the early power-off angle, a pin retraction command is sent to the solenoid valve.

[0102] Since the advance power-off angle is actually the crankshaft angle of the engine corresponding to the time when the pin retraction command is sent to the solenoid valve is advanced relative to the conventional time, this advance power-off angle should be the crankshaft angle of the engine within the time period between the separation of the pin from the valve switching drive and the target axial displacement required for the camshaft sleeve to complete the valve lift switching. Simultaneously, the axial displacement of the camshaft sleeve corresponding to this advance power-off angle should reach a preset proportion of the target axial displacement, which is 50% in this embodiment, to ensure that the camshaft sleeve has passed the switching point of the valve lift switching process and can continue to move axially to the target position to complete the valve lift switching in an undriven autonomous state. Only on this basis is the advance power-off angle usable. When the pin separates from the valve switching drive, the crankshaft angle of the engine will vary under different system operating parameters, such as engine speed and temperature. Therefore, when using advance power-off to retract the pin, it is necessary to determine the crankshaft angle corresponding to the separation of the pin from the valve switching drive under the current system operating parameters and ensure that the advance power-off angle is greater than this crankshaft angle.

[0103] Figure 6 A schematic diagram of the forces acting on the cam sleeve in one embodiment of this application is shown. Figure 6 As shown, F1 is the contact force generated by the contact between the left or right solenoid valve pin and the valve switching drive device, and its direction is always the same as the movement direction of the cam sleeve. F2 is the frictional force between the cam sleeve and the camshaft, and its direction is always opposite to the movement direction of the cam sleeve. F3 is the component force of the cam sleeve resisting the thrust ball 6 in the first half of the switching stroke, and F3' is the component force of the cam sleeve resisting the thrust ball 6 in the second half of the switching stroke. In the first half of the switching stroke, F3' is in the same direction as F2, and in the second half of the switching stroke, F3' is in the opposite direction to F2. When F1 + F3' > F2, the cam sleeve will separate from the pin under the resultant force of the internal forces, thus resulting in… Figure 4 The diagram shows the situation where the cam sleeve decelerates freely to the target position during the latter half of the stroke. In this embodiment, the axial displacement of the cam sleeve at the moment of early power-off must reach a preset ratio of the target axial displacement. This is to ensure that the thrust ball 6 can overcome the elastic force of the thrust spring 7 and pass over the protrusion between the two slots during the valve lift switching process. This protrusion corresponds to the switching point during the valve lift switching process, thereby ensuring that the valve lift switching can be successfully achieved.

[0104] Figure 7 The following is a flowchart illustrating the application of a valve lift switching control method in one embodiment of this application, including the following steps S701 to S706.

[0105] Step S701: The system detects whether the required valve lift, which is actively set by the user or automatically determined, is consistent with the current actual valve lift.

[0106] In step S702, if the required valve lift is consistent with the current actual valve lift, there is no need to perform a valve lift switching action; if the required valve lift is inconsistent with the current actual valve lift, the advance energizing angle is calculated based on the current solenoid valve response time and engine speed.

[0107] Step S703: Compare the advance power-on angle with 720°CA. If the advance power-on angle is less than 720°CA, the advance power-on angle is determined to be usable, and the calculation stage of the advance power-off angle begins.

[0108] Step S704: Calculate the advance power-off angle based on the current solenoid valve response time and engine speed.

[0109] Step S705: Determine the threshold range of the early power-off angle, that is, compare the early power-off angle with the crankshaft angle of the engine when the cam sleeve completes the target axial displacement, and compare the axial displacement of the cam sleeve corresponding to the early power-off angle with the preset ratio of the target axial displacement.

[0110] Step S706: If the early power-off angle meets the threshold range, then the solenoid valve is controlled and adjusted according to the aforementioned early power-on angle and early power-off angle.

[0111] Furthermore, based on the above embodiments, before obtaining the advance power-on angle in step S100, the switching control method further includes the following steps S105 to S110.

[0112] Step S105: Obtain the extreme value of the energizing angle for controlling the extension pin of the solenoid valve. The extreme value of the energizing angle is the maximum or minimum energizing angle corresponding to the valve lift switching that enables the extension pin of the solenoid valve to complete.

[0113] Step S106: Generate the energizing angle range based on the extreme values ​​of the energizing angle.

[0114] Step S107: Determine the advance energizing angle within the energizing angle range.

[0115] Step S108: Obtain the extreme value of the de-energizing angle for controlling the retracting pin of the solenoid valve. The extreme value of the de-energizing angle is the maximum or minimum de-energizing angle corresponding to the valve lift switching that enables the retracting pin of the solenoid valve to be controlled.

[0116] Step S109: Generate a power-off angle range based on the extreme values ​​of the power-off angle.

[0117] Step S110: Determine the advance power-off angle within the power-off angle range.

[0118] Specifically, in this embodiment, through theoretical calculations or actual testing, the extreme value of the energizing angle corresponding to the limit state that enables the solenoid valve to extend the pin and complete the valve lift switching under various response times of the solenoid valve and engine speed conditions is obtained. Based on this extreme value, an energizing angle range is determined. Furthermore, a universal energizing angle is selected from this range and applied as the advance energizing angle during the valve lift switching process. This eliminates the need to calculate the advance energizing angle for each valve lift switching, thereby reducing the system's computational burden and cost. It can be understood that for the extraction de-energizing angle for controlling the solenoid valve to retract the pin, a universal de-energizing angle can be determined within the de-energizing angle range using the same determination method as the universal energizing angle, thus eliminating the need for repeated calculations of the extraction de-energizing angle.

[0119] The following describes an embodiment of the apparatus of this application, which can be used to execute the valve lift switching control method in the above embodiments of this application. Figure 8 A schematic block diagram of the valve lift switching control device provided in an embodiment of this application is shown. Figure 8 As shown, the valve lift switching control device includes:

[0120] The acquisition module is configured to acquire the advance energization angle, which is a first preset angle determined based on the response time of the solenoid valve.

[0121] The sending module is configured to send a pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle if the advance energizing angle is less than the energizing angle threshold. The pin extension command is used to instruct the solenoid valve to extend the pin so that the pin cooperates with the valve switching drive device to realize valve lift switching.

[0122] In one embodiment of this application, based on the above embodiments, the acquisition module includes:

[0123] The command triggering unit is configured to trigger a lift switching command if the required valve lift does not match the current valve lift.

[0124] The parameter detection unit is configured to detect the current system operating parameters according to the lift switching command, and to obtain the response time of the solenoid valve according to the system operating parameters;

[0125] An angle calculation unit is configured to acquire the current engine speed and calculate the advance energization angle based on the engine speed and the response time.

[0126] In one embodiment of this application, based on the above embodiments, the valve lift switching control device further includes:

[0127] The valve lift determination module is configured to acquire changes in state parameters fed back by the solenoid valve, wherein different position states of the pin correspond to different state parameters; and to determine the position state of the pin based on the changes in the state parameters; and to determine the current valve lift based on the position state of the pin.

[0128] In one embodiment of this application, based on the above embodiments, the valve lift switching control device further includes:

[0129] An angle comparison module is configured to compare the pre-energization angle with the first rotation angle value.

[0130] In one embodiment of this application, based on the above embodiments, the valve lift switching control device further includes:

[0131] The power-off control module is configured to acquire an early power-off angle, which is a second preset angle determined based on the response time of the solenoid valve, the second preset angle being different from the first preset angle; and, if the early power-off angle reaches a power-off angle threshold, when the crankshaft angle of the engine reaches the early power-off angle, a pin retraction command is sent to the solenoid valve, the pin retraction command being used to instruct the solenoid valve to retract the pin.

[0132] In one embodiment of this application, based on the above embodiments, the power failure control module includes:

[0133] The power-off threshold determination unit is configured to acquire a second rotation angle value corresponding to the engine crankshaft when the engine cam sleeve reaches a preset proportion of the target axial displacement required to complete valve lift switching; and to acquire a third rotation angle value corresponding to the engine crankshaft when the pin separates from the valve switching drive device during valve lift switching, based on system operating parameters; and to determine the power-off angle threshold within a numerical range greater than the second rotation angle value and the third rotation angle value.

[0134] The power-off control unit is configured to send a pin retraction command to the solenoid valve when the crankshaft angle of the engine reaches the power-off angle threshold if the early power-off angle reaches the power-off angle threshold.

[0135] In one embodiment of this application, based on the above embodiments, the valve lift switching control device further includes:

[0136] An extreme energizing angle determination module is configured to acquire an extreme energizing angle for controlling the extension pin of the solenoid valve, wherein the extreme energizing angle is the maximum or minimum energizing angle corresponding to the valve lift switching that enables the extension pin of the solenoid valve to be switched; and to generate an energizing angle range based on the extreme energizing angle; and to determine the advance energizing angle within the energizing angle range.

[0137] The de-energizing extreme value determination module is configured to acquire the extreme value of the de-energizing angle for controlling the retraction pin of the solenoid valve, wherein the extreme value of the de-energizing angle is the maximum or minimum de-energizing angle corresponding to the valve lift switching that enables the retraction pin of the solenoid valve; and to generate a de-energizing angle range based on the extreme value of the de-energizing angle; and to determine the advance de-energizing angle within the de-energizing angle range.

[0138] Figure 9 A schematic block diagram of a computer system architecture for implementing an electronic device according to embodiments of the present application is shown.

[0139] It should be noted that, Figure 9 The computer system 900 of the electronic device shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments of this application.

[0140] like Figure 9 As shown, the computer system 900 includes a central processing unit (CPU) 901, which can perform various appropriate actions and processes based on programs stored in read-only memory (ROM) 902 or programs loaded from storage section 908 into random access memory (RAM). The RAM 903 also stores various programs and data required for system operation. The CPU 901, ROM 902, and RAM 903 are interconnected via a bus 904. An input / output interface 905 (I / O interface) is also connected to the bus 904.

[0141] The following components are connected to the input / output interface 905: an input section 906 including a keyboard, mouse, etc.; an output section 907 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 908 including a hard disk, etc.; and a communication section 909 including a network interface card such as a local area network card, modem, etc. The communication section 909 performs communication processing via a network such as the Internet. A drive 910 is also connected to the input / output interface 905 as needed. A removable medium 911, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on the drive 910 as needed so that computer programs read from it can be installed into the storage section 908 as needed.

[0142] Specifically, according to embodiments of this application, the processes described in the various method flowcharts can be implemented as computer software programs. For example, embodiments of this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication section 909, and / or installed from removable medium 911. When the computer program is executed by central processing unit 901, it performs various functions defined in the system of this application.

[0143] It should be noted that the computer-readable medium shown in the embodiments of this application can be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), flash memory, optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such transmitted data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to wireless, wired, etc., or any suitable combination thereof.

[0144] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0145] It should be noted that although several modules or units for the device used to perform actions have been mentioned in the detailed description above, this division is not mandatory. In fact, according to the embodiments of this application, the features and functions of two or more modules or units described above can be embodied in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided and embodied by multiple modules or units.

[0146] Through the above description of the embodiments, those skilled in the art will readily understand that the exemplary embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solutions according to the embodiments of this application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, external hard drive, etc.) or on a network, including several instructions to cause a computing device (such as a personal computer, server, touch terminal, or network device, etc.) to execute the method according to the embodiments of this application.

[0147] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0148] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A method for switching valve lift, characterized in that, The switching control method includes: The advance energizing angle is obtained, which is a first preset angle determined based on the response time of the solenoid valve; If the advance energizing angle is less than the energizing angle threshold, when the crankshaft angle of the engine reaches the advance energizing angle, a pin extension command is sent to the solenoid valve. The pin extension command is used to instruct the solenoid valve to extend the pin so that the pin cooperates with the valve switching drive device to achieve valve lift switching. The early power-off angle is obtained, which is a second preset angle determined based on the response time of the solenoid valve. The second preset angle is different from the first preset angle. The preset proportion of the target axial displacement required for the engine cam sleeve to complete the valve lift switching is obtained, and the second rotation angle value of the engine crankshaft is obtained accordingly. The third rotation angle value of the engine crankshaft is obtained according to the system operating parameters when the pin separates from the valve switching drive device during the valve lift switching process. The power-off angle threshold is determined within a numerical range greater than the second rotation angle value and the third rotation angle value. If the pre-power-off angle reaches the pre-power-off angle threshold, when the crankshaft angle of the engine reaches the pre-power-off angle, a pin retraction command is sent to the solenoid valve. The pin retraction command is used to instruct the solenoid valve to retract the pin.

2. The valve lift switching control method as described in claim 1, characterized in that, Obtain the pre-energization angle, including: If the required valve lift does not match the current valve lift, a lift switching command is triggered; The current system operating parameters are detected according to the lift switching command, and the response time of the solenoid valve is obtained according to the system operating parameters. The current engine speed is obtained, and the advance energizing angle is calculated based on the engine speed and the response time.

3. The valve lift switching control method as described in claim 2, characterized in that, Before triggering a lift switching command if the required valve lift does not match the current valve lift, the switching control method further includes: The changes in the state parameters fed back by the solenoid valve are obtained, wherein different position states of the pin correspond to different state parameters; The position state of the pin is determined based on the changes in the state parameters; The current valve lift is determined based on the position of the pin.

4. The valve lift switching control method as described in claim 1, characterized in that, The energizing angle threshold is the first rotation angle value corresponding to the rotation cycle of the engine crankshaft. If the advance energizing angle is less than the energizing angle threshold, before sending the pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle, the switching control method further includes: The pre-energization angle is compared with the first rotation angle value.

5. The valve lift switching control method as described in claim 1, characterized in that, Before obtaining the advance energization angle, the switching control method further includes: Obtain the extreme value of the energizing angle used to control the extension pin of the solenoid valve, wherein the extreme value of the energizing angle is the maximum or minimum energizing angle corresponding to the valve lift switching that enables the extension pin of the solenoid valve to be switched. The energizing angle range is generated based on the extreme values ​​of the energizing angle. The advance energizing angle is determined within the energizing angle range; and / or, Obtain the extreme value of the de-energizing angle for controlling the retraction pin of the solenoid valve, wherein the extreme value of the de-energizing angle is the maximum or minimum de-energizing angle corresponding to the valve lift switching that enables the retraction pin of the solenoid valve to be controlled. The power-off angle range is generated based on the extreme values ​​of the power-off angle. The early power-off angle is determined within the range of power-off angles.

6. A valve lift switching control device, characterized in that, The valve lift switching control device is configured to perform the valve lift switching control method according to any one of claims 1 to 5, the valve lift switching control device comprising: The acquisition module is configured to acquire the advance energization angle, which is a first preset angle determined based on the response time of the solenoid valve. The sending module is configured to send a pin extension command to the solenoid valve when the crankshaft angle of the engine reaches the advance energizing angle if the advance energizing angle is less than the energizing angle threshold. The pin extension command is used to instruct the solenoid valve to extend the pin so that the pin cooperates with the valve switching drive device to realize valve lift switching.

7. A terminal device, characterized in that, The terminal device includes: a memory, a processor, and a valve lift switching control program stored in the memory and executable on the processor. When the valve lift switching control program is executed by the processor, it implements the valve lift switching control method as described in any one of claims 1 to 5.

8. A storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements the valve lift switching control method as described in any one of claims 1 to 5.

Images