A solenoid valve and its control method, device, and braking system

Abstract

The present invention provides a solenoid valve and its control method, device, and brake system. The solenoid valve includes: a valve seat, having a accommodating cavity, a liquid inlet hole, and a liquid outlet hole, wherein the liquid inlet hole and the liquid outlet hole are respectively connected to the accommodating cavity to form a fluid channel; a valve core, slidably and sealingly connected to the inner wall of the accommodating cavity, for controlling the opening of the fluid channel; a magnetic isolation tube, connected to the valve seat, the inner cavity of the magnetic isolation tube is connected to the accommodating cavity; an electromagnetic moving iron, movably arranged in the magnetic isolation tube; a coil, at least partially sleeved on the magnetic isolation tube, for driving the electromagnetic moving iron to move; an elastic member, arranged between the electromagnetic moving iron and the valve core, and compressing the elastic member when the electromagnetic moving iron and the valve core move toward each other. The solenoid valve of the present invention has a simple structure and can minimize the NVH risk in the control process of the solenoid valve.

Description

Technical Field

[0001] The present invention relates to the technical field of solenoid valves, and in particular, to a solenoid valve, a control method, a device, and a braking system thereof. Background Art

[0002] The braking system is mainly used to control the deceleration of a vehicle and is an important component for ensuring vehicle safety. Among them, the hydraulic power-assisted braking system controls the opening degree of a solenoid valve to control the flow rate of the brake fluid, thereby achieving vehicle braking. It has good braking effects and is widely used in various vehicle models.

[0003] Currently, most of the solenoid valves in the hydraulic power-assisted braking system adopt on-off valves such as ball valves, which adjust the brake fluid flow rate by quickly opening and closing. However, on the one hand, the frequent opening and closing of the solenoid valve will cause NVH (Noise, Vibration, Harshness) risks. For example, when the ball valve closes, the seating is likely to cause NVH risks, and the timeliness of the control process is poor. On the other hand, the structures of on-off valves such as ball valves are complex and not convenient for processing. Summary of the Invention

[0004] The problem solved by the present invention is how to simplify the structure of the solenoid valve and avoid NVH risks during the control process of the solenoid valve.

[0005] To solve the above problems, the present invention provides a solenoid valve, a control method, a device, and a braking system thereof.

[0006] In a first aspect, the present invention provides a solenoid valve, including:

[0007] A valve seat having a receiving cavity, a liquid inlet hole, and a liquid outlet hole. The liquid inlet hole and the liquid outlet hole are respectively communicated with the receiving cavity to form a fluid passage;

[0008] A valve core slidably and sealingly connected to the inner wall of the receiving cavity for controlling the opening degree of the fluid passage;

[0009] A magnetic isolation tube connected to the valve seat, and the inner cavity of the magnetic isolation tube is communicated with the receiving cavity;

[0010] An electromagnetic armature movably arranged in the magnetic isolation tube;

[0011] A coil at least partially sleeved on the magnetic isolation tube for driving the movement of the electromagnetic armature;

[0012] An elastic member arranged between the electromagnetic armature and the valve core. When the electromagnetic armature and the valve core move towards each other, the elastic member is compressed.

[0013] Optionally, the number of the liquid outlet holes is multiple, and the multiple liquid outlet holes are uniformly distributed along the axial direction and / or the circumferential direction of the valve seat.

[0014] Optionally, an exhaust hole communicating with the accommodation cavity is provided on the electromagnetic armature.

[0015] Optionally, a filter screen is provided at the liquid inlet hole and the liquid outlet hole.

[0016] In a second aspect, the present invention provides a solenoid valve control method based on the solenoid valve according to any one of the first aspect. The solenoid valve control method includes:

[0017] Obtain the target output flow rate of the solenoid valve;

[0018] Control the fluid to flow into the accommodation cavity from the liquid inlet hole to drive the valve core to move;

[0019] Determine the target current of the coil according to the preset corresponding relationship between the target output flow rate. The preset corresponding relationship includes the corresponding coil current and the output flow rate of the solenoid valve;

[0020] Control the coil according to the target current to control the position of the valve core, so that the output flow rate of the solenoid valve is controlled to reach the target output flow rate.

[0021] Optionally, before determining the target current of the coil according to the preset corresponding relationship between the target output flow rate, the method further includes:

[0022] Determine the coil current and the output flow rate of the solenoid valve when the valve core maintains dynamic balance at different positions;

[0023] Establish the preset corresponding relationship according to the corresponding coil current and the output flow rate of the solenoid valve.

[0024] Optionally, determining the coil current and the output flow rate of the solenoid valve when the valve core maintains dynamic balance at different positions includes:

[0025] Adjust the coil current to control the working stroke of the elastic member to control the position of the valve core;

[0026] When the valve core moves to the position to be calibrated and the valve core reaches dynamic balance, determine the corresponding coil current and output flow rate of the solenoid valve.

[0027] Optionally, controlling the coil according to the target current to control the position of the valve core includes:

[0028] Obtain the actual current of the coil;

[0029] Determine a control current based on the target current and the actual current;

[0030] Based on a preset rule, determine a duty cycle signal according to the control current;

[0031] Control the coil according to the duty cycle signal to control the position of the spool valve.

[0032] In a third aspect, the present invention provides a solenoid valve control device, comprising:

[0033] An acquisition module for acquiring the target output flow rate of the solenoid valve;

[0034] A first control module for controlling fluid to flow from the liquid inlet hole into the accommodation cavity to drive the spool valve to move;

[0035] A processing module for determining the target current of the coil according to the preset corresponding relationship between the target output flow rate, the preset corresponding relationship including the corresponding coil current and the output flow rate of the solenoid valve;

[0036] A second control module for controlling the coil according to the target current to control the position of the spool valve so that the output flow rate of the solenoid valve reaches the target output flow rate.

[0037] In a fourth aspect, the present invention provides a braking system comprising a solenoid valve according to any one of the first aspects.

[0038] The beneficial effects of the solenoid valve, its control method, device, and braking system of the present invention are as follows: Fluid can flow from the liquid inlet hole into the accommodation cavity of the valve seat, applying a liquid pressure to the spool valve in the accommodation cavity. When an electric current is passed through the coil, an electromagnetic force is generated to drive the electromagnetic armature to move in the direction close to the spool valve, compressing the elastic member to generate a spring force, and the spring force acts on the spool valve. Under the combined action of the spring force and the liquid pressure, the movement of the spool valve is controlled. When the spring force, the liquid pressure, and the electromagnetic force reach dynamic equilibrium, the position of the spool valve no longer changes. Different spool valve positions correspond to different fluid passage opening degrees, or rather, different spool valve positions correspond to different output flow rates of the solenoid valve, that is, the flow rate of the liquid outlet hole. Therefore, by changing the coil current to control the position of the spool valve, the opening degree of the fluid passage is controlled, and further the output flow rate of the solenoid valve is controlled, reducing the opening and closing frequency of the solenoid valve to avoid the NVH risk caused by the frequent closing of the solenoid valve. And the solenoid valve of the present invention has a simple structure and is easy to process. Description of the Drawings

[0039] Figure 1 It is a schematic structural diagram of the solenoid valve according to an embodiment of the present invention;

[0040] Figure 2 It is a schematic flow diagram of the solenoid valve control method according to an embodiment of the present invention;

[0041] Figure 3 Schematic diagram of the corresponding relationship between the coil current and the output flow rate during the calibration process of the embodiment of the present invention;

[0042] Figure 4 Schematic diagram of the corresponding relationship between the coil current, the spring force and the spring working stroke of the embodiment of the present invention;

[0043] Figure 5 Schematic diagram of the structure of the solenoid valve control device of the embodiment of the present invention.

[0044] Description of the reference numerals:

[0045] 1, valve seat; 2, valve core; 3, magnetic isolation tube; 4, electromagnetic armature; 5, elastic member; 11, accommodating cavity; 12, liquid inlet hole; 13, liquid outlet hole. Detailed implementation manners

[0046] To make the above objects, features and advantages of the present invention more obvious and understandable, the following will describe the specific embodiments of the present invention in detail with reference to the accompanying drawings. Although some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments described herein. On the contrary, these embodiments are provided to more thoroughly and completely understand the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not used to limit the protection scope of the present invention.

[0047] It should be understood that the various steps recorded in the method embodiments of the present invention can be executed in different orders and / or executed in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this regard.

[0048] The term "including" and its variants used herein are open-ended, that is, "including but not limited to". The term "based on" is "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optionally" means "optional embodiment". The relevant definitions of other terms will be given in the following description. It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence relationship of the functions executed by these devices, modules or units.

[0049] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly stated in the context, it should be understood as "one or more".

[0050] The names of the messages or information exchanged between multiple devices in the embodiments of the present invention are for illustrative purposes only and are not used to limit the scope of these messages or information.

[0051] As Figure 1 shown, a solenoid valve provided by an embodiment of the present invention can be applied to control the flow rate of brake fluid in a braking system, and includes:

[0052] A valve seat 1 having a receiving cavity 11, a liquid inlet hole 12, and a liquid outlet hole 13, wherein the liquid inlet hole 12 and the liquid outlet hole 13 are respectively communicated with the receiving cavity 11 to form a fluid channel.

[0053] Specifically, the receiving cavity 11 in the valve seat 1 can extend axially. The liquid inlet hole 12 is used to inject fluid so that the fluid enters the receiving cavity 11, and the liquid outlet hole 13 is used for the fluid in the receiving cavity 11 to flow out. The liquid inlet hole 12 can be communicated with the axial bottom or top of the receiving cavity 11, and the liquid outlet hole 13 can be communicated with the side surface of the receiving cavity 11. When the fluid flows into the receiving cavity 11 from the liquid inlet hole 12, it drives the valve core 2 in the receiving cavity 11 to move axially. The valve core 2 moves to open the fluid channel, and the fluid in the receiving cavity 11 flows out through the liquid outlet hole 13.

[0054] Exemplarily, as Figure 1 shown, when the solenoid valve is placed vertically, the liquid inlet hole 12 can be communicated with the bottom of the receiving cavity 11, and the liquid outlet hole 13 can be arranged on the side surface of the receiving cavity 11 and communicated with the receiving cavity 11. The fluid flows into the bottom of the receiving cavity 11 from the liquid inlet hole 12, driving the valve core 2 to move axially. When the valve core 2 moves and no longer blocks the liquid outlet hole 13, the fluid in the receiving cavity 11 flows out through the liquid outlet hole 13.

[0055] A valve core 2, which is slidably and sealingly connected to the inner wall of the receiving cavity 11 and is used to control the opening degree of the fluid channel.

[0056] Specifically, the valve core 2 can adopt a plunger valve core 2, which is slidably and sealingly connected to the inner wall of the receiving cavity 11 and can move along the extending direction of the receiving cavity 11, for example, move axially. The valve core 2 can control the opening degree of the fluid channel by opening or blocking the liquid outlet hole 13. For example, the liquid outlet hole 13 can be a long strip-shaped hole such as a kidney-shaped hole. The valve core 2 moves axially to control the opening degree of the long strip-shaped hole such as the kidney-shaped hole, thereby controlling the fluid flow rate; or, a plurality of liquid outlet holes 13 can be uniformly arranged along the side surface of the receiving cavity 11, and the valve core 2 moves axially to control the number of the opened liquid outlet holes 13, thereby controlling the fluid flow rate.

[0057] A magnetic isolation tube 3, which is connected to the valve seat 1, and the inner cavity of the magnetic isolation tube 3 is communicated with the receiving cavity 11.

[0058] Specifically, the magnetic isolation tube 3 can be axially connected to the valve seat 1, and sealing connection methods such as laser welding and threaded connection can be adopted. The magnetic isolation tube 3 is used for magnetic isolation and guiding the movement of the electromagnetic armature 4.

[0059] The electromagnetic armature 4 is movably arranged inside the magnetic isolation tube 3.

[0060] Specifically, the electromagnetic armature 4 can move axially along the magnetic isolation tube 3, and its movement stroke is small, which can be specifically set according to actual needs. The cross-sectional area of the electromagnetic armature 4 can be larger than the cross-sectional area of the accommodation cavity 11 to prevent it from entering the accommodation cavity 11 during the movement.

[0061] A coil (not shown in the figure) is at least partially sleeved on the magnetic isolation tube 3 and is used to drive the movement of the electromagnetic armature 4.

[0062] Specifically, the coil is sleeved on the magnetic isolation tube 3. When the coil is energized, the electromagnetic armature 4 is controlled to move in the direction close to the valve core 2.

[0063] An elastic member 5 is arranged between the electromagnetic armature 4 and the valve core 2. When the electromagnetic armature 4 and the valve core 2 move towards each other, the elastic member 5 is compressed.

[0064] Specifically, the elastic member 5 can be a spring, a spring sheet, etc. When the elastic member 5 is in the initial state, the valve core 2 blocks the fluid passage. When the valve core 2 and the electromagnetic armature 4 move towards each other, the elastic member 5 is compressed to open the fluid passage.

[0065] Exemplarily, the elastic member 5 can be compressively arranged between the electromagnetic armature 4 and the valve core 2. One end of it abuts against the end of the valve core 2 away from the fluid, and the other end abuts against the electromagnetic armature 4.

[0066] In this embodiment, the fluid can flow into the accommodation cavity 11 of the valve seat 1 from the liquid inlet hole 12, and a liquid pressure is applied to the valve core 2 in the accommodation cavity 11. When an electric current is passed through the coil, an electromagnetic force is generated to drive the electromagnetic armature 4 to move in the direction close to the valve core 2, compressing the elastic member 5 to generate a spring force, and the spring force acts on the valve core 2. Under the combined action of the spring force and the liquid pressure, the movement of the valve core 2 is controlled. When the spring force, the liquid pressure, and the electromagnetic force reach dynamic equilibrium, the position of the valve core 2 no longer changes. Different valve core positions correspond to different fluid passage opening degrees, or rather, different valve core positions correspond to different solenoid valve output flows, that is, the flow rate of the liquid outlet hole 13. Therefore, by changing the coil current, the position of the valve core 2 is controlled to control the opening degree of the fluid passage, and further the output flow rate of the solenoid valve is controlled, reducing the opening and closing frequency of the solenoid valve to avoid the NVH risk caused by the frequent closing of the solenoid valve. And the solenoid valve of the present invention has a simple structure and is easy to process.

[0067] Exemplarily, when the coil current changes, the change process of the output flow rate of the solenoid valve is as follows:

[0068] When the coil current decreases, the electromagnetic force acting on the electromagnetic armature 4 weakens, and the spring force relatively increases, driving the electromagnetic armature 4 to move away from the valve core 2, and the working stroke of the elastic member 5 shrinks. The shrinkage of the working stroke of the elastic member 5 causes the spring force to decrease. The decrease in the spring force causes the hydraulic pressure to relatively increase, driving the valve core 2 to move towards the electromagnetic armature 4, increasing the opening of the fluid passage, increasing the output flow rate of the solenoid valve, causing the hydraulic pressure to decrease until the hydraulic pressure, spring force, and electromagnetic force are equal, reaching a new dynamic equilibrium.

[0069] When the coil current increases, the electromagnetic force acting on the electromagnetic armature 4 increases, and the spring force relatively decreases, driving the electromagnetic armature 4 to move towards the valve core 2, and the working stroke of the elastic member 5 increases. The increase in the working stroke of the elastic member 5 causes the spring force to increase. The increase in the spring force causes the hydraulic pressure to relatively decrease, driving the valve core 2 to move away from the electromagnetic armature 4, reducing the opening of the fluid passage, reducing the output flow rate of the solenoid valve, causing the hydraulic pressure to increase until the hydraulic pressure, spring force, and electromagnetic force are equal, reaching a new dynamic equilibrium.

[0070] Optionally, the number of the liquid outlet holes 13 is multiple, and the multiple liquid outlet holes 13 are evenly distributed along the axial direction and / or the circumferential direction of the valve seat 1.

[0071] Specifically, a plurality of liquid outlet holes 13 can be provided on the side surface of the accommodation cavity 11. When the liquid outlet holes 13 are evenly distributed along the axial direction of the valve seat 1, the valve core 2 moving along the axial direction can control the number of the opened liquid outlet holes 13, thereby controlling the output flow rate of the solenoid valve.

[0072] A plurality of liquid outlet holes 13 can also be evenly arranged along the circumferential direction on the side surface of the accommodation cavity 11, such as long strip-shaped holes extending axially like kidney-shaped holes. The valve core 2 moving along the axial direction can control the opening degree of the liquid outlet holes 13, thereby controlling the output flow rate of the solenoid valve.

[0073] In this optional embodiment, a plurality of liquid outlet holes 13 are evenly arranged along the axial direction and / or the axial direction of the valve seat 1. By controlling the number of the opened liquid outlet holes 13 and / or the opening degree of the liquid outlet holes 13, linear control of the output flow rate of the solenoid valve can be achieved, and the control process is simple and the timeliness is higher.

[0074] Optionally, an exhaust hole communicating with the accommodation cavity 11 is provided on the electromagnetic armature 4.

[0075] In this optional embodiment, an exhaust hole communicating with the accommodation cavity 11 is provided on the electromagnetic armature 4. When the electromagnetic armature 4 and the valve core 2 move towards each other to compress the spring, the gas in the accommodation cavity 11 can be discharged from the exhaust hole, avoiding the generation of air resistance in the accommodation cavity 11 and affecting the control accuracy of the valve core 2.

[0076] Optionally, filters are provided at the liquid inlet hole 12 and the liquid outlet hole 13.

[0077] In this optional embodiment, filters are provided at the liquid inlet hole 12 and the liquid outlet hole 13 to prevent foreign matters such as impurities in the fluid from entering the accommodation chamber 11 and prevent the spool 2 from being stuck by foreign matters.

[0078] As Figure 2 shown, a solenoid valve control method provided by an embodiment of the present invention is based on the solenoid valve as described above. The solenoid valve control method includes:

[0079] Step S100, obtaining the target output flow rate of the solenoid valve.

[0080] Specifically, the target output flow rate is the target flow rate that the solenoid valve needs to output. For example, when the driver steps on the brake pedal according to the braking demand to input a braking signal, the target output flow rate of the brake fluid matching the braking signal is determined. The specific processing process is the prior art and will not be elaborated here.

[0081] Step S200, controlling the fluid to flow into the accommodation chamber 11 from the liquid inlet hole 12 to drive the spool 2 to move; determining the target current of the coil according to the preset corresponding relationship between the target output flow rate, and the preset corresponding relationship includes the corresponding coil current and the output flow rate of the solenoid valve.

[0082] Specifically, controlling the fluid to flow into the accommodation chamber 11 from the liquid inlet hole 12, the fluid injected into the accommodation chamber 11 exerts a hydraulic pressure on the spool 2 to drive the spool 2 to move axially. Query the coil current corresponding to the target output flow rate in the preset corresponding relationship according to the target output flow rate, and this coil current is the target current. The corresponding relationship between the coil current and the output flow rate of the solenoid valve can be determined by calibration in advance.

[0083] Step S300, controlling the coil according to the target current to control the position of the spool 2 so that the output flow rate of the solenoid valve reaches the target output flow rate.

[0084] Specifically, controlling the coil according to the target current, the coil generates an electromagnetic force to drive the electromagnetic armature 4 to move towards the direction close to the spool 2 to compress the elastic member 5, and further control the position of the spool 2. Taking the elastic member 5 as a spring as an example, when the spring force generated by the compression of the spring is equal to the hydraulic pressure exerted on the spool 2 by the fluid, the spool 2 reaches dynamic equilibrium. At this time, the position where the spool 2 is located enables the corresponding opening degree of the fluid passage to be opened so that the output flow rate of the solenoid valve reaches the target output flow rate.

[0085] In this embodiment, the target output flow rate that the solenoid valve needs to output is obtained, and the fluid is controlled to flow into the accommodation chamber 11 from the liquid inlet hole 12. The target current corresponding to the target output flow rate is determined according to a pre-calibrated preset correspondence relationship, and the coil is controlled according to the target current, and an electromagnetic force is applied to the electromagnetic armature 4. The electromagnetic armature 4 moves under the action of the electromagnetic force to compress or stretch the elastic member 5, thereby changing the balance relationship of the valve core 2 to control the movement of the valve core 2. When the valve core 2 moves to a position corresponding to the target current, a dynamic balance is reached again, and the opening degree of the fluid passage corresponding to the valve core 2 at this position enables the output flow rate of the solenoid valve to reach the target output flow rate. By changing the coil current to control the position of the valve core 2, linear control of the opening degree of the fluid passage can be achieved, and further linear control of the output flow rate of the solenoid valve can be achieved. Compared with the prior art in which the solenoid valve is frequently opened and closed to control the output flow rate of the solenoid valve, the opening and closing frequency of the solenoid valve is reduced, and the NVH risk caused by the frequent closing of the solenoid valve is avoided.

[0086] Optionally, before determining the target current of the coil according to the preset correspondence relationship between the target output flow rate, it further includes:

[0087] Determine the coil current of the solenoid valve and the output flow rate when the valve core 2 maintains dynamic balance at different positions.

[0088] Specifically, the coil current of the solenoid valve and the output flow rate required for the valve core 2 to reach dynamic balance at different positions are pre-calibrated. For any position of the valve core 2, when the spring force and the liquid pressure acting on the valve core 2 at this position are equal, it means that the valve core 2 reaches dynamic balance, that is, the valve core 2 can stay at this position, so that the fluid passage can be opened to the corresponding opening degree.

[0089] Establish the preset correspondence relationship according to the corresponding coil current and the output flow rate of the solenoid valve.

[0090] Specifically, establish the correspondence relationship between the coil current and the output flow rate of the solenoid valve, then the corresponding output flow rate can be directly determined from this correspondence relationship according to the coil current.

[0091] In this optional embodiment, the coil current and the output flow rate required for the valve core 2 to reach dynamic balance at different positions are pre-calibrated in advance, so that the coil current corresponding to the target output flow rate can be quickly determined when controlling the solenoid valve, improving the control efficiency.

[0092] Optionally, determining the coil current of the solenoid valve and the output flow rate when the valve core 2 maintains dynamic balance at different positions includes:

[0093] Adjust the coil current to control the working stroke of the elastic member 5 to control the position of the valve core 2.

[0094] Specifically, the coil current is adjusted to adjust the electromagnetic force applied to the electromagnetic armature 4. Since the electromagnetic force is balanced with the spring force, when the electromagnetic force changes, the spring force changes, and the balance relationship between the spring force and the hydraulic pressure exerted by the fluid on the valve core 2 changes. The valve core 2 moves under the action of the force, and its position changes until the electromagnetic force, the spring force, and the hydraulic pressure reach a new balance again.

[0095] When the valve core 2 moves to the position to be calibrated and the valve core 2 reaches dynamic equilibrium, the coil current and the output flow rate of the corresponding solenoid valve are determined.

[0096] Specifically, for any position to be calibrated of the valve core 2, when the coil current is adjusted to make the valve core 2 move to this position to be calibrated and the electromagnetic force, the spring force, and the hydraulic pressure of the valve core 2 reach a new dynamic equilibrium at this position to be calibrated, the coil current and the output flow rate of the solenoid valve at this time are determined, and the calibration of the coil current and the output flow rate of the valve core 2 at this position to be calibrated can be realized, that is, the corresponding relationship between the coil current and the output flow rate corresponding to this position to be calibrated is determined.

[0097] Exemplarily, as Figure 3 shown, for any position to be calibrated, the coil current can be controlled to decrease from the maximum current value, and the change of the output flow rate during the decrease of the coil current is recorded. The decrease of the coil current weakens the electromagnetic force applied to the electromagnetic armature 4, which in turn causes the spring force to relatively increase, breaking the balance system. The valve core 2 and the electromagnetic armature 4 move, and the movement of the valve core 2 affects the opening degree of the fluid passage, thereby affecting the output flow rate of the solenoid valve.

[0098] When the valve core 2 moves to this position to be calibrated and the spring force is equal to the hydraulic pressure applied to the valve core 2 and the electromagnetic force applied to the electromagnetic armature 4, it means that the valve core 2 reaches a new balance at this position to be calibrated. The time point when the new balance is reached is the balance point, as Figure 3 shown, the coil current and the output flow rate corresponding to the balance point are the calibration results at this position to be calibrated.

[0099] As Figure 4 shown, from the calibration results, it can be known that the working stroke of the spring is positively correlated with the coil current and the spring force. In order to maintain dynamic equilibrium, when the working stroke of the spring increases and the spring force increases, a larger electromagnetic force (i.e., coil current) is required to maintain the balance; when the working stroke of the spring becomes smaller and the spring force becomes smaller, a smaller electromagnetic force (i.e., coil current) is required to maintain the balance.

[0100] Optionally, the controlling the coil according to the target current to control the position of the valve core 2 includes:

[0101] Obtaining the actual current of the coil.

[0102] Determine a control current based on the target current and the actual current.

[0103] Specifically, a deviation between the actual current of the coil at present and the target current can be determined as the control current.

[0104] Based on a preset rule, determine a duty ratio signal according to the control current.

[0105] Specifically, the preset rule can be a corresponding relationship between the preset control current and the duty ratio signal, or a PID (Proportion Integration Differentiation) control method can be adopted. For example, a PID control method is used for closed-loop control according to the difference between the actual current and the target current to determine the corresponding duty ratio signal.

[0106] Control the coil according to the duty ratio signal to control the position of the spool 2.

[0107] Specifically, the duty ratio signal is used to control the coil to apply a corresponding electromagnetic force to the electromagnetic armature 4 to control the position of the spool 2, so that the fluid passage opens a corresponding opening degree, and further enables the output flow rate of the solenoid valve to reach the target output flow rate.

[0108] In this alternative embodiment, the regulation speed and control accuracy of the coil current can be improved through closed-loop control.

[0109] As Figure 5 shown, a solenoid valve control device provided by an embodiment of the present invention includes:

[0110] An acquisition module, configured to acquire the target output flow rate of the solenoid valve;

[0111] A first control module, configured to control fluid to flow into the accommodation chamber 11 from the liquid inlet hole 12 to drive the spool 2 to move;

[0112] A processing module, configured to determine the target current of the coil according to the target output flow rate and a preset corresponding relationship, where the preset corresponding relationship includes corresponding coil current and the output flow rate of the solenoid valve;

[0113] A second control module, configured to control the coil according to the target current to control the position of the spool 2, so that the output flow rate of the solenoid valve reaches the target output flow rate.

[0114] The solenoid valve control device of this embodiment is used to implement the solenoid valve control method as described above, and its advantages over the prior art are the same as those of the above solenoid valve control method over the prior art, and will not be elaborated herein.

[0115] Optionally, it further includes a calibration module, and the calibration module is configured to: determine the coil current and the output flow rate of the solenoid valve when the valve core 2 maintains dynamic balance at different positions; establish the preset correspondence relationship according to the corresponding coil current and the output flow rate of the solenoid valve.

[0116] Optionally, the calibration module is specifically configured to: adjust the coil current to control the working stroke of the elastic member 5 so as to control the position of the valve core 2; when the valve core 2 moves to the position to be calibrated and the valve core 2 reaches dynamic balance, determine the corresponding coil current and the output flow rate of the solenoid valve.

[0117] Optionally, the second control module is specifically configured to: obtain the actual current of the coil; determine the control current according to the target current and the actual current; determine the duty cycle signal according to the control current based on a preset rule; control the coil according to the duty cycle signal so as to control the position of the valve core 2.

[0118] A braking system provided by another embodiment of the present invention includes the solenoid valve as described above.

[0119] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above methods. Among them, the storage medium can be a magnetic disk, an optical disc, a read-only memory (ROM), or a random access memory (RAM), etc. In the present application, the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present invention. In addition, the functional units in the various embodiments of the present invention can be integrated in one processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units.

[0120] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will all fall within the protection scope of the present invention.

Claims

1. A solenoid valve control method, characterized in that, Based on a solenoid valve, the solenoid valve includes: a valve seat (1) having a receiving cavity (11), a liquid inlet hole (12), and a liquid outlet hole (13), the liquid inlet hole (12) and the liquid outlet hole (13) are respectively communicated with the receiving cavity (11) to form a fluid channel; a valve core (2) slidably and sealingly connected to the inner wall of the receiving cavity (11) for controlling the opening degree of the fluid channel; a magnetic isolation tube (3) connected to the valve seat (1), the inner cavity of the magnetic isolation tube (3) is communicated with the receiving cavity (11); an electromagnetic armature (4) movably arranged in the magnetic isolation tube (3); a coil at least partially sleeved on the magnetic isolation tube (3) for driving the electromagnetic armature (4) to move; an elastic member (5) arranged between the electromagnetic armature (4) and the valve core (2), when the electromagnetic armature (4) and the valve core (2) move towards each other, the elastic member (5) is compressed; The solenoid valve control method includes: Obtaining the target output flow rate of the solenoid valve; Controlling the fluid to flow into the receiving cavity (11) from the liquid inlet hole (12) to drive the valve core (2) to move; Determining the target current of the coil according to the preset corresponding relationship between the target output flow rate, the preset corresponding relationship includes the corresponding coil current and the output flow rate of the solenoid valve; Controlling the coil according to the target current to control the position of the valve core (2) so that the output flow rate of the solenoid valve reaches the target output flow rate; Before determining the target current of the coil according to the preset corresponding relationship between the target output flow rate, it further includes: determining the coil current and the output flow rate of the solenoid valve when the valve core (2) maintains dynamic balance at different positions; establishing the preset corresponding relationship according to the corresponding coil current and the output flow rate of the solenoid valve; Determining the coil current and the output flow rate of the solenoid valve when the valve core (2) maintains dynamic balance at different positions includes: adjusting the coil current, controlling the working stroke of the elastic member (5) to control the position of the valve core (2); when the valve core (2) moves to the position to be calibrated and the valve core (2) reaches dynamic balance, determining the corresponding coil current and the output flow rate of the solenoid valve.

2. The solenoid valve control method according to claim 1, wherein The number of the liquid outlet holes (13) is multiple, and the multiple liquid outlet holes (13) are uniformly distributed along the axial direction and / or the circumferential direction of the valve seat (1).

3. The solenoid valve control method according to claim 1 or 2, characterized in that, An exhaust hole communicated with the receiving cavity (11) is arranged on the electromagnetic armature (4).

4. The solenoid valve control method according to claim 1 or 2, characterized in that Filter meshes are arranged at the liquid inlet hole (12) and the liquid outlet hole (13).

5. The solenoid valve control method according to claim 1, characterized in that Controlling the coil according to the target current to control the position of the valve core (2) includes: Obtaining the actual current of the coil; Determining the control current according to the target current and the actual current; Based on a preset rule, determining a duty ratio signal according to the control current; Controlling the coil according to the duty ratio signal to control the position of the valve core (2).

6. An electromagnetic valve control device, characterized in that, For implementing the solenoid valve control method according to any one of claims 1 to 5, it includes: An acquisition module for acquiring the target output flow rate of the solenoid valve; The first control module is used to control the fluid to flow into the accommodation chamber (11) from the liquid inlet hole (12) to drive the valve core (2) to move; The processing module is used to determine the target current of the coil according to the target output flow rate and the preset corresponding relationship, and the preset corresponding relationship includes the corresponding coil current and the output flow rate of the solenoid valve; The second control module is used to control the coil according to the target current to control the position of the valve core (2) so that the output flow rate of the solenoid valve reaches the target output flow rate.

7. A braking system, characterized in that, It includes a solenoid valve, and the solenoid valve is controlled by the solenoid valve control method according to any one of claims 1 to 5.

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