Control method of lifting bridge with locking function

Abstract

The invention relates to a lifting axle control method with a locking function, which comprises the following steps that: after a vehicle is powered on, in a static state or when the running speed is less than V, an ECAS acquires height information acquired by a suspension height sensor, converts the height information into whole vehicle load information, and sends the whole vehicle load information to a whole vehicle controller VECU through a CAN bus; the VECU compares the load information with the set light-load and heavy-load suspension height values and autonomously judges the current load condition of the vehicle; at the moment, a lifting air bag loop is connected, a lifting inflation valve or a descending deflation valve is powered on, inflation or deflation of the lifting air bag is achieved, and lifting or descending of the lifting bridge is completed; and if the vehicle speed exceeds V, the VECU locks logic controlled by the ECAS lifting air bag and the switch, and at the moment, lifting or descending of the lifting axle cannot be achieved, so that the stability of the vehicle is kept. The suspension height information of the ECAS is shared to the vehicle control unit VECU, the vehicle load condition is judged through the suspension height, the vehicle automatic weighing function is achieved, and automatic lifting and descending of the lifting axle are executed.

Description

Technical Field

[0001] The invention relates to the field of chassis suspension control, and in particular to a lifting bridge control method with a locking function. Background Art

[0002] Lifting axles are common configurations for multi-axle heavy-duty commercial vehicles, and drivers can choose to switch between light-load and heavy-load scenarios. Lifting axles usually also have a follow-up steering function, which can be locked and unlocked when the vehicle is in forward gear, and must be locked when in reverse gear to prevent tire and axle collisions. The lifting / lowering and locking / unlocking functions of the lifting axle are equipped with corresponding switches and status indicators in the cab for the driver to select operations.

[0003] Most of the lifting axles currently on the market are manually controlled. The driver makes judgments based on the actual driving conditions, and the controller receives control signals from the cab switches to adjust the chassis height of the vehicle. This control method is greatly affected by the driver's subjective factors and cannot respond accurately and promptly to various working conditions. Summary of the invention

[0004] To solve the above problems, the present invention provides a lifting axle control method with a locking function, which determines the vehicle load condition by the suspension height, realizes the vehicle automatic weighing function, and performs automatic lifting and lowering of the lifting axle.

[0005] The technical solution adopted by the present invention is: a lifting bridge control method with a locking function, characterized in that it includes the following steps: after the vehicle is powered on, in a stationary state or when the driving speed is less than V, ECAS (Electronic-controlled air suspension electronically controlled air suspension system) collects height information collected by the suspension height sensor, converts it into vehicle load information, and sends the vehicle load information to the vehicle controller VECU (vehicle electronic control unit) through the CAN bus, and the VECU compares the load information with the set light load and heavy load suspension height values ​​to independently judge the current load condition of the vehicle; at this time, the lifting airbag circuit is connected, the lifting inflation valve or the lowering deflation valve is energized, the lifting airbag is inflated or deflated, and the lifting or lowering of the lifting bridge is completed; if the vehicle speed exceeds V, the VECU locks the logic of the ECAS lifting airbag and switch control, and the lifting or lowering of the lifting bridge cannot be achieved at this time to maintain the stability of the vehicle.

[0006] As a preferred embodiment, the lifting axle gear control mode is: when engaging the reverse gear, no matter what state the follow-up steering control switch is in, the vehicle controller VECU pin connected to the locking relay control end only outputs a low-level pulse to activate the locking inflation valve, complete the inflation, and lock the lifting and lowering function of the lifting axle; when exiting the reverse gear, the vehicle controller VECU pin connected to the unlocking relay automatically outputs a low-level pulse to activate the unlocking exhaust valve, complete the exhaust, and unlock the lifting and lowering function of the lifting axle.

[0007] As a preferred option, the manual control mode of the lifting axle is activated when the gear is in neutral, and the vehicle controller VECU reads the status signal of the follow-up steering control switch in real time; the switch is manually operated to lock the gear, and the vehicle controller VECU reads the high-level signal of the switch lock and outputs a high-level pulse to the locking relay control end, thereby activating the locking inflation valve, completing the inflation, and locking the lifting and lowering function of the lifting axle; the switch is manually operated to unlock the gear, and the vehicle controller VECU reads the high-level signal of the switch unlock, and outputs a high-level pulse to the unlocking relay control end, thereby activating the unlocking exhaust valve, completing the exhaust, and unlocking the lifting and lowering function of the lifting axle.

[0008] Preferably, the lifting inflation valve, the lowering deflation valve, the locking inflation valve and the unlocking exhaust valve are all two-position three-way solenoid valves, and the working medium is compressed air.

[0009] Preferably, the lifting inflation valve, the lowering deflation valve, the locking inflation valve and the unlocking exhaust valve are all controlled by high-level pulse signals with a duration of less than 30ms. They take action after receiving the electrical signal and maintain the state after the action.

[0010] Preferably, the two coils of the lifting inflation valve, the lowering deflation valve, the locking inflation valve and the unlocking exhaust valve are driven independently and do not work at the same time. The coils are driven by pulse signals and matched with non-self-locking self-resetting switches.

[0011] Preferably, an on-off air pressure alarm is installed on the lifting airbag to sense the inflation and deflation status of the airbag. The alarm is connected to the instrument cluster, and the instrument lights up the status indicator light corresponding to the airbag according to the change of the electric level.

[0012] Preferably, V is 15 km / h.

[0013] Preferably, the vehicle controller VECU reads the transmission gear status through the CAN bus and monitors two hard-wired signals of the status of the follow-up steering control switch; the vehicle controller VECU has two outputs to independently drive the follow-up unlocking relay and the follow-up locking relay control terminals.

[0014] The beneficial effects achieved by the present invention are as follows: the suspension height information of ECAS is shared with the vehicle controller VECU, the vehicle load condition is judged by the suspension height, the vehicle automatic weighing function is realized, and the automatic lifting and lowering of the lifting bridge is performed; the vehicle speed signal enabling switch control circuit is designed, and the switch and relay adapted to the high-level pulse triggering solenoid valve are selected (a circuit composed of a non-self-locking non-self-resetting rocker switch and an electronic relay is selected to drive the solenoid valve); the logical relationship between the gear position and the switch control follow-up steering unlocking and locking is identified, and the automatic mode of the gear position control is entered only in the reverse gear, and the hardware circuit and driver program that do not interfere with the switch control when not in the reverse gear are designed; the present invention has the following advantages:

[0015] 1. The vehicle is equipped with a built-in weighing function to identify the load condition and realize automatic lifting and lowering of the lifting axle;

[0016] 2. The pneumatic actuator for lifting the lifting axle and locking the follow-up steering has a memory function, which can keep the function activated after a short-term output of the electrical drive to avoid the electrical drive unit being powered on all the time;

[0017] 3. The follow-up steering function of the lifting axle in the lowered state when the vehicle is in reverse gear must be locked, regardless of whether the driver manually presses the lock switch;

[0018] 4. The priority of reverse gear is higher than manual control. When the vehicle is in reverse gear, it will be automatically locked and unlocked when the reverse gear is over, thus realizing the gear control follow-up steering mode;

[0019] 5. The vehicle does not enter the gear control follow-up steering mode when it is not in reverse gear, and the switch needs to be manually operated to lock or unlock;

[0020] 6. When the lifting axle is in the lifting or steering lock state, the instrument provides sound and light signals to remind the driver. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the lifting bridge lifting and steering locking control circuit of the present invention;

[0022] Figure 2 It is a schematic diagram of the solenoid valve structure;

[0023] Figure 3 Schematic diagram of switch positions;

[0024] Figure 4 It is the schematic diagram of the lifting bridge status indicator circuit;

[0025] In the figure: 1. VECU; 2. ECAS; 3. Lifting inflation valve; 4. Lowering deflation valve; 5. Lifting relay; 6. Lowering relay; 7. Lifting axle lifting control switch; 8. Locking inflation valve; 9. Unlocking exhaust valve; 10. Unlocking relay; 11. Locking relay; 12. Follow-up steering control switch; 13. Instrument cluster; s1. Lifting axle lifting airbag pressure switch; s2. Lifting axle lowering airbag pressure switch; s3. Follow-up steering locking airbag pressure switch; s4. Follow-up steering unlocking airbag pressure switch; L1. Lifting axle lifting indicator light; L2. Lifting axle lowering indicator light; L3. Follow-up steering locking indicator light; L4. Follow-up steering unlocking indicator light. DETAILED DESCRIPTION

[0026] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0028] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] like Figure 1-4As shown, a lifting axle control method with a locking function of the present invention, after the vehicle is powered on, in a stationary state or when the driving speed is less than V, ECAS (Electronic-controlled air suspension) collects height information collected by the suspension height sensor, converts it into vehicle load information, and sends the vehicle load information to the vehicle controller VECU (vehicle electronic control unit) through the CAN bus, and VECU compares the load information with the set light load and heavy load suspension height values ​​to independently determine the current load condition of the vehicle; at this time, the lifting airbag circuit is connected, and the lifting inflation valve 3 or the lowering deflation valve 4 is energized to realize the inflation or deflation of the lifting airbag, and complete the lifting or lowering of the lifting axle; if the vehicle speed exceeds V, VECU locks the logic of the ECAS lifting airbag and switch control, and the lifting or lowering of the lifting axle cannot be realized at this time to maintain the stability of the vehicle.

[0030] In this embodiment, the lifting axle gear control mode is: when engaging the reverse gear, no matter what state the follow-up steering control switch 12 is in, the vehicle controller VECU pin connected to the control end of the locking relay 11 only outputs a low-level pulse to activate the locking inflation valve 8, complete the inflation, and lock the lifting and lowering function of the lifting axle; when exiting the reverse gear, the vehicle controller VECU pin connected to the unlocking relay 10 automatically outputs a low-level pulse to activate the unlocking exhaust valve 9, complete the exhaust, and unlock the lifting and lowering function of the lifting axle.

[0031] In this embodiment, the manual control mode of the lifting axle is activated when the gear is in neutral, and the vehicle controller VECU reads the status signal of the follow-up steering control switch 12 in real time; the switch is manually operated to lock the gear, and the vehicle controller VECU reads the high-level signal of the switch lock and outputs a high-level pulse to the control end of the locking relay 11, activates the locking inflation valve 8, completes the inflation, and locks the lifting and lowering function of the lifting axle; the switch is manually operated to unlock the gear, and the vehicle controller VECU reads the high-level signal of the switch unlock, and outputs a high-level pulse to the control end of the unlocking relay 10, activates the unlocking exhaust valve 9, completes the exhaust, and unlocks the lifting and lowering function of the lifting axle.

[0032] In this embodiment, the lifting inflation valve 3, the lowering deflation valve 4, the locking inflation valve 8 and the unlocking exhaust valve 9 are all two-position three-way solenoid valves, and the working medium is compressed air.

[0033] In this embodiment, the lifting inflation valve 3, the lowering deflation valve 4, the locking inflation valve 8 and the unlocking exhaust valve 9 are all controlled by high-level pulse signals with a duration of less than 30ms. After receiving the electrical signal, they generate an action and maintain the state after the action.

[0034] In this embodiment, the two coils of the lifting inflation valve 3, the lowering deflation valve 4, the locking inflation valve 8 and the unlocking exhaust valve 9 are driven independently and do not work at the same time. The coils are driven by pulse signals and matched with non-self-locking self-resetting switches.

[0035] Combination Figure 4 As shown, in this embodiment, an on-off air pressure alarm is installed on the lifting airbag to sense the inflation and deflation status of the airbag. The alarm is connected to the instrument cluster 13, and the instrument cluster 13 lights up the status indicator light corresponding to the airbag according to the level change.

[0036] In this embodiment, a lifting bridge control method with a locking function includes the following steps:

[0037] After the vehicle is powered on, in a stationary state or when the vehicle speed is less than 15km / h (calibrable), ECAS collects the height information collected by the suspension height sensor, converts it into vehicle load information, and sends the load information to the vehicle controller VECU through the CAN bus. VECU compares the signal with the set light load and heavy load suspension height values, autonomously determines the current load of the vehicle, and automatically lifts and lowers the lifting axle. At this time, VECU connects the circuit controlled by the lifting axle lifting control switch 7, and can also manually operate the single-pole double-throw three-state switch to actively select the lifting airbag lifting inflation valve 3 or the lowering deflation valve 4 to energize, so as to inflate or deflate the airbag and complete the lifting or lowering of the lifting axle.

[0038] If the vehicle speed exceeds the calibrated value (15km / h), the EVCU will lock the logic of the ECAS automatic airbag lifting and lowering control switch 7. At this time, the airbag cannot be raised or lowered to maintain the stability of the vehicle.

[0039] Since the airbag only has two states, lifting and lowering, it is only necessary to install an on-off air pressure alarm on the airbag to sense the inflation and deflation state of the airbag, and the alarm is connected to the instrument cluster 13. The instrument cluster 13 lights up the status indicator corresponding to the airbag according to the level change.

[0040] The steering lock function is divided into gear position control mode and manual control mode. The specific implementation methods are as follows:

[0041] The reverse gear has the highest priority. When the reverse gear is engaged at any speed, no matter what state the follow-up steering control switch 12 is in, the vehicle controller pin connected to the control end of the locking relay 11 only outputs a low-level pulse to activate the locking inflation valve 8 to complete inflation; when exiting the reverse gear, the vehicle controller pin connected to the unlocking relay 10 automatically outputs a low-level pulse to activate the unlocking exhaust valve 9 to exhaust - this is the gear control mode;

[0042] The manual control mode is only activated when the gear is in neutral, and the vehicle controller reads the status signal of the follow-up steering control switch 12 in real time. When the vehicle is in neutral (no speed limit), when the switch is manually operated to lock the gear, the vehicle controller reads the high-level signal of the switch lock and outputs a high-level pulse to the control end of the lock relay 11, activating the lock inflation valve 8 to complete the inflation; when the switch is manually operated to unlock the gear, the vehicle controller reads the high-level signal of the switch unlock and outputs a high-level pulse to the control end of the unlock relay 10, activating the unlock exhaust valve 9 to exhaust - this is the manual control mode.

[0043] The present invention has the following functions:

[0044] 1. Automatic weighing function

[0045] The air suspension control unit ECAS sends the collected suspension height sensor position signal to the vehicle controller VECU through the CAN bus. VECU compares the signal with the set light load and heavy load suspension height values, independently determines the current load condition of the vehicle, and automatically lifts and lowers the lifting axle.

[0046] 2. Solenoid valve with memory function (combined with Figure 2 (shown)

[0047] The solenoid valve is a two-position three-way structure. The working medium is compressed air. It includes an air charging solenoid valve and an exhaust solenoid valve. It is controlled by a high-level pulse signal with a duration of less than 30ms. After receiving the electrical signal, the solenoid valve will act and maintain the state after the action.

[0048] 3. Selection of control switch (combined with Figure 3 (shown)

[0049] The two coils of the solenoid valve are driven independently and will not work at the same time, so a three-state switch is selected, and the contact structure is single-pole double-throw; the coil is driven by a pulse signal, that is, inching control, and needs to be matched with a non-self-locking self-reset switch.

[0050] 4. Vehicle speed signal enables lifting and lowering circuit of lifting bridge

[0051] Only when the vehicle speed reaches the set value, the lifting axle lifting control switch 7 is enabled, otherwise it will not respond to the driver's switch operation; this scheme adopts relays (lifting relay 5 and lowering relay 6) in series into the lifting and lowering switch circuit of the lifting axle, and the control ends of the two relays are driven by the high side of the same pin of the vehicle controller. When the vehicle speed is lower than the set value (which can be calibrated), a high-level pulse is output to enable the switch control circuit; when the vehicle speed is higher than the set value, the switch control circuit is cut off, making the switch invalid.

[0052] 5. Gear position and manual steering lock function circuit

[0053] The vehicle controller reads the gear position status of the transmission through the CAN bus and monitors two hard-wired signals of the status of the follow-up steering control switch 12. The vehicle controller has two outputs to independently drive the control terminals of the unlocking relay 10 and the locking relay 11.

[0054] 6. Lifting and steering lock state sensing element of lifting axle (combined with Figure 4 (shown)

[0055] The lifting / lowering and unlocking / locking airbags of the lifting axle are operated by compressed air. A pressure sensor or a pressure switch can be selected to sense the airbag pressure. Since it is only necessary to sense the pressure change after the airbag is inflated and deflated, and there is no need to continuously monitor the airbag pressure, it is more appropriate to choose a pressure switch, which is also more advantageous in terms of cost and technical difficulty. The normal air pressure value of the vehicle is greater than 8Mpa, and the time it takes for the airbag to inflate or deflate is less than 10S. Consider using a normally open pressure switch with an alarm value of 7Mpa. The pressure switch signal is directly connected to the alarm light pin of the instrument cluster. The light goes out when it is open, and the light turns on when the pin is grounded when it is closed.

[0056] The above shows and describes the basic principles and main structural features of the present invention. The present invention is not limited to the above examples. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

[0057] It should be noted that the description of the above technical solutions is exemplary, and this specification can be embodied in different forms and should not be interpreted as being limited to the technical solutions set forth herein. On the contrary, providing these descriptions will make the disclosure of the present invention thorough and complete, and will fully convey the scope disclosed in this specification to those skilled in the art. In addition, the technical solutions of the present invention are limited only by the scope of the claims.

[0058] The shapes, sizes, ratios, angles, and numbers disclosed for describing various aspects of the present specification and claims are merely examples, and therefore, the present specification and claims are not limited to the details shown. In the following description, when the detailed description of the related known functions or configurations is determined to be unnecessarily obscuring the focus of the present specification and claims, the detailed description will be omitted.

[0059] In the case of using “including”, “having” and “comprising” described in the present specification, unless otherwise used, there may also be another part or other parts, and the terms used may generally be in the singular but may also represent the plural form.

[0060] It should be noted that although the terms "first", "second", "top", "bottom", "one side", "the other side", "one end", "the other end", etc. may appear and be used in this specification to describe various components, these components and parts should not be limited by these terms. These terms are only used to distinguish one component and part from another component and part. For example, without departing from the scope of this specification, the first component can be called the second component, and similarly, the second component can be called the first component. The components at the top and bottom can also be swapped or converted with each other under certain circumstances; the components at one end and the other end can have the same or different performances.

[0061] When describing a positional relationship, for example, when the positional sequence is described as "on ...", "above ...", "below ..." and "next", unless words or terms such as "just" or "directly" are used, situations where they are not in contact or in contact may also be included. If it is mentioned that a first element is "on" a second element, it does not mean that the first element must be above the second element in the figure. The upper and lower parts of the component will change according to the change of the angle and orientation of observation. Therefore, in the drawings or in the actual construction, if it is involved that the first element is "on" the second element, the situation where the first element is "below" the second element and the situation where the first element is "above" the second element may be included. When describing a temporal relationship, unless "just" or "directly" is used, when describing "after", "subsequently", "subsequently" and "before", situations where the steps are not continuous may be included. The features of various embodiments of the present invention may be partially or completely combined or spliced ​​with each other, and may be performed in various different configurations as can be fully understood by those skilled in the art. The embodiments of the present invention may be performed independently of each other, or may be performed together in a mutually dependent relationship.

[0062] Finally, it should be pointed out that the above embodiments are only representative examples of the present invention. Obviously, the present invention is not limited to the above embodiments, and there are many variations. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention should be considered to belong to the protection scope of the present invention.

Claims

1. A lifting bridge control method with locking function, characterized in that: The following steps are involved: After the vehicle is powered on, when it is stationary or traveling at a speed less than V, ECAS collects the height information collected by the suspension height sensor, converts it into vehicle load information, and sends the vehicle load information to the vehicle controller VECU through the CAN bus. VECU compares the load information with the set light load and heavy load suspension height values, and independently determines the current load condition of the vehicle; at this time, the lifting airbag circuit is connected, and the lifting inflation valve or the lowering deflation valve is energized to inflate or deflate the lifting airbag, completing the lifting or lowering of the lifting axle; if the vehicle speed exceeds V, VECU locks the logic of the ECAS lifting airbag and switch control, and the lifting or lowering of the lifting axle cannot be achieved at this time to maintain the stability of the vehicle.

2. The lifting bridge control method with locking function according to claim 1, characterized in that: Lifting axle gear control mode: When engaging reverse gear, no matter what state the follow-up steering control switch is in, the vehicle controller VECU pin connected to the locking relay control end only outputs a low-level pulse to activate the locking inflation valve, complete the inflation, and lock the lifting and lowering function of the lifting axle; when exiting reverse gear, the vehicle controller VECU pin connected to the unlocking relay automatically outputs a low-level pulse to activate the unlocking exhaust valve, complete the exhaust, and unlock the lifting and lowering function of the lifting axle.

3. The lifting bridge control method with locking function according to claim 1 or 2, characterized in that: The manual control mode of the lifting axle is activated when the gear is in neutral. The vehicle controller VECU reads the status signal of the follow-up steering control switch in real time; the switch is manually operated to lock the gear. After the vehicle controller VECU reads the high-level signal of the switch lock, it outputs a high-level pulse to the locking relay control end, activates the locking inflation valve, completes the inflation, and locks the lifting and lowering function of the lifting axle; the switch is manually operated to unlock the gear. After the vehicle controller VECU reads the high-level signal of the switch unlock, it outputs a high-level pulse to the unlocking relay control end, activates the unlocking exhaust valve, completes the exhaust, and unlocks the lifting and lowering function of the lifting axle.

4. The lifting bridge control method with locking function according to claim 3 is characterized in that: The lifting inflation valve, lowering deflation valve, locking inflation valve and unlocking exhaust valve are all two-position three-way solenoid valves, and the working medium is compressed air.

5. The lifting bridge control method with locking function according to claim 3, characterized in that: The lifting inflation valve, lowering deflation valve, locking inflation valve and unlocking exhaust valve are all controlled by high-level pulse signals with a duration of less than 30ms. They will take action after receiving the electrical signal and maintain the state after the action.

6. The lifting bridge control method with locking function according to claim 5, characterized in that: The two coils of the lifting inflation valve, the lowering deflation valve, the locking inflation valve and the unlocking exhaust valve are driven independently and do not work at the same time. The coils are driven by pulse signals and matched with non-self-locking self-resetting switches.

7. The lifting bridge control method with locking function according to claim 3, characterized in that: An on-off air pressure alarm is installed on the lifting airbag to sense the inflation and deflation status of the airbag. The alarm is connected to the instrument cluster, and the instrument cluster lights up the status indicator light corresponding to the airbag according to the changes in the electrical level.

8. The lifting bridge control method with locking function according to claim 1, characterized in that: V is 15km / h.

9. The lifting bridge control method with locking function according to claim 1, characterized in that: The vehicle controller VECU reads the gear position status of the transmission through the CAN bus and monitors two hard-wired signals of the status of the follow-up steering control switch; the vehicle controller VECU has two outputs to independently drive the follow-up unlocking relay and the follow-up locking relay control terminals.

Images