Automobile air brake ABS solenoid valve spool assembly

Abstract

The application discloses a kind of automobile air brake ABS solenoid valve valve core assembly, belong to brake solenoid valve field, including the valve core of sliding setting in guide sleeve inside and the solenoid coil of being set in the outside of valve core, the end of valve core is provided with reset spring, the head end of valve core is connected with crank connecting rod driving mechanism, crank connecting rod driving mechanism includes speed reducer motor, the output shaft of being connected with speed reducer motor crank and the connecting rod of one end being hinged with crank, the other end of connecting rod passes through guide bushing and is hinged with valve core after slider, guide bushing is coaxially arranged with valve core.Using the above-mentioned automobile air brake ABS solenoid valve valve core assembly, utilizes the non-constant speed characteristic of crank slider, realizes peak linear velocity 1.2m / s in switching stage, ensures that air path switching is completed within 0.42ms.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of brake solenoid valves, in particular to an automobile air brake ABS solenoid valve spool assembly. BACKGROUND

[0002] The automobile anti-lock braking system (ABS) prevents wheel lock by adjusting the brake chamber pressure, and is a core component for ensuring driving safety. The solenoid valve, as a key executive element of the ABS system, directly affects the braking effect. The traditional ABS solenoid valve generally adopts an electromagnetic drive structure, which has the following technical defects:

[0003] 1. Insufficient response speed: The electromagnetic drive relies on the electromagnetic force generated by the coil power supply, and is affected by the coil inductance and the inertia of the iron core. The response time is usually more than 5-10 ms, which is difficult to meet the pressure regulation demand of high frequency (>100 Hz).

[0004] 2. The electromagnetic drive needs continuous power supply to maintain the spool position, and the standby power consumption is 5-10 W.

[0005] 3. Limited service life: The electromagnetic coil is easy to heat and age after long-term power supply, which leads to increased resistance and decreased electromagnetic force, eventually causing the spool to jam or fail to fully open.

[0006] 4. Poor sealing reliability: The contact seal between the spool and the valve seat is easily affected by wear and corrosion, and the leakage rate increases after long-term use, resulting in a decrease in brake pressure control accuracy. For example, the leakage of the existing solenoid valve under 200 bar pressure for 180 s should be less than 500 mm 3 , but in actual application, the sealing failure often exceeds the standard. SUMMARY

[0007] The purpose of the application is to provide an automobile air brake ABS solenoid valve spool assembly to solve the above technical problems.

[0008] To achieve the above purpose, the application provides an automobile air brake ABS solenoid valve spool assembly, which comprises a spool slidingly arranged in a guide sleeve and an electromagnetic coil sleeved on the outer side of the spool. The end of the spool is provided with a return spring, the head end of the spool is connected with a crank and connecting rod driving mechanism, the crank and connecting rod driving mechanism comprises a speed reducer, a crank connected with the output shaft of the speed reducer, and a connecting rod hingedly connected with the crank, the other end of the connecting rod is hingedly connected with the spool through a sliding block after passing through a guide sleeve, and the guide sleeve is coaxially arranged with the spool.

[0009] Preferably, the application further comprises an electromagnetic coupling mechanism, which comprises a flywheel arranged at the end of the crank shaft, a permanent magnet arranged in the flywheel, and a stator coil sleeved on the outer side of the flywheel. The stator coil is electrically connected with an energy storage unit through a rectifier bridge, and is used to recover energy during the deceleration stage of the spool.

[0010] Preferably, the stator coil is also electrically connected with the output end of the double-ECU through a PWM modulator, and the input end of the double-ECU is electrically connected with an encoder arranged on the crank, so as to adjust the crank angle by using the electromagnetic induction principle according to the collected angle of the encoder.

[0011] Preferably, the stator coil adopts a high-frequency response design, the response time is less than or equal to 0.1 ms, the current is less than or equal to 2 A, and the ±10 N·m torque adjustment can be provided.

[0012] Preferably, the stator coil adopts 240 turns of enameled wire with a wire diameter of 0.5 mm, and a soft magnetic core is arranged inside, the material of the soft magnetic core is silicon steel sheet, and the magnetic permeability μ r = 2000.

[0013] Preferably, the flywheel adopts gray cast iron, the mass is 0.5-1.0 kg, and the rotational inertia is 0.01-0.03 kg·m 2

[0014] Preferably, the valve core adopts 42CrMo hardened steel, the surface is quenched to HRC 58-62, the guide sleeve adopts tin bronze, the hardness is HB180-220, and the surface roughness Ra of the two is less than or equal to 0.2 μm.

[0015] Preferably, the valve core is a stepped shaft structure and is slidingly fitted in the inner hole of the guide sleeve, the radial gap between the two is 5 μm-10 μm, and a double-lip sealing structure is arranged between the two.

[0016] Preferably, the double-lip sealing structure includes an inner lip-shaped ring and an outer lip-shaped ring, the inner lip-shaped ring adopts a contact type sealing made of fluororubber, and the outer lip-shaped ring adopts a non-contact type throttling sealing made of polytetrafluoroethylene.

[0017] Therefore, the valve core assembly of the automobile air brake ABS electromagnetic valve has the beneficial effects that:

[0018] 1. High-speed response: the non-constant speed characteristics of the crank slider (the peak speed is concentrated in the switching stage) are utilized to realize 0.42 ms level hard switching, and the dynamic coupling (coupling efficiency ≥ 90%) between the electromagnetic coil and the flywheel gear ring is utilized to provide ±0.05 mm level position fine adjustment at low speed, so as to solve the poor controllability problem of pure mechanical driving at high speed;

[0019] 2. The flywheel stores kinetic energy (rotational inertia 0.015 kg·m 2 ) during the deceleration stage of the valve core, and the kinetic energy is converted into electric energy (recovery power 5-8 W) through electromagnetic induction, so that the energy consumption of single switching is reduced to 1 / 3 of that of a traditional electromagnetic valve;

[0020] ​3. Mechanical drive (crank slider), electromagnetic drive to form redundant backup, realize when double ECU detects mechanical failure, switch to pure electromagnetic mode within 0.5ms;

[0021] 4. Adopt double lip seal design, test condition is 34.5MPa, static leakage is controlled within 10mL / min, provide guarantee for long life operation (≥100 million cycles) of vehicle-mounted environment.

[0022] Long life operation: mechanical drive avoids the heating aging problem of electromagnetic coil, cooperates with hardened steel valve core and wear-resistant copper alloy guide sleeve, and the service life is improved to more than 100 million times.

[0023] The technical solutions of the present application will be further described in detail below with the help of drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 It is a sectional view of a valve core assembly of an automobile air brake ABS electromagnetic valve of the present application.

[0025] REFERENCE NUMERALS

[0026] 1. Guide sleeve; 2. Valve core; 3. Reset spring; 4. Double lip seal structure; 5. Electromagnetic coil; 6. Slider; 7. Connecting rod; 8. Guide sleeve; 9. Crank; 10. Permanent magnet; 11. Stator coil; 12. Reducing motor; 13. Flywheel. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present application more clear and understandable, the embodiments of the present application will be further described in detail below with the help of drawings and examples. It should be understood that the specific embodiments described here are only used to explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application. The examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout.

[0028] It should be noted that the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or server including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0029] The embodiments of the present application will be described in detail below with the help of drawings.

[0030] AsFigure 1 As shown, a valve core assembly of an automobile air brake ABS solenoid valve includes a valve core 2 slidingly arranged inside a guide sleeve 1 and an electromagnetic coil 5 sleeved outside the valve core 2, the valve core 2 is provided with a reset spring 3 at the end thereof, the head end of the valve core 2 is connected with a crank link driving mechanism, the crank link driving mechanism includes a speed reduction motor 12, a crank 9 connected with the output shaft of the speed reduction motor 12 and a link 7 hinged at one end with the crank 9, the other end of the link 7 is hinged with the valve core 2 through a sliding block 6 after passing through a guide sleeve 8, and the guide sleeve 8 is coaxially arranged with the valve core 2.

[0031] In the embodiment, the radius r of the crank 9 is 11.43 mm, the length l of the link 7 is 5r=57.15 mm, the stroke x of the sliding block 6 is 2r=22.86 mm, the displacement accuracy of the valve core 2 is ±0.05 mm (achieved by electromagnetic coupling fine adjustment), the speed reduction motor 12 drives the crank 9 at a speed ratio i of 6:1, and the rated speed of the speed reduction motor 12 is 7200 rpm, corresponding to the maximum speed of the crank 9 of 1200 rpm, covering the commonly used frequency range (50-120 Hz) of the ABS system.

[0032] The application further includes an electromagnetic coupling mechanism, which includes a flywheel 13 arranged at the shaft end of the crank 9, a permanent magnet 10 arranged inside the flywheel 13 and a stator coil 11 sleeved outside the flywheel 13, the stator coil 11 is electrically connected with an energy storage unit through a rectifier bridge, for recovering energy in the deceleration stage of the valve core 2.

[0033] The flywheel generator composed of the permanent magnet 10 and the stator coil 11 has an efficiency of ≥75%, and the energy recovery rate of single switching is ≥30%, the energy storage unit is an energy storage capacitor, and the capacity of the energy storage capacitor is 50 mF, which can maintain 3 times of emergency switching in the electromagnetic driving mode.

[0034] Specifically, in the embodiment, the flywheel stores kinetic energy in the deceleration stage of the sliding block 6 (the crank 9 rotates from 90° to 180°), generates electric energy by cutting the stator coil 11 with the permanent magnet, and recovers about 0.05J energy in single switching, so that the system energy consumption is reduced from 300mJ / time of the traditional solenoid valve to below 100mJ / time.

[0035] The stator coil 11 is also electrically connected with the output end of a double ECU through a PWM modulator, and the input end of the double ECU is electrically connected with an encoder arranged on the crank 9, for adjusting the crank angle by using electromagnetic induction principle according to the collected angle of the encoder.

[0036] It should be noted that the above electronic components are all mature products in the market, and the embodiment only needs to connect them according to the instructions after purchasing, and does not improve them, so the circuit connection structure and principle will not be described here.

[0037] The stator coil 11 adopts high frequency response design, the response time is less than or equal to 0.1 ms, the current is less than or equal to 2 A, and the ±10 N.m torque adjustment can be provided.

[0038] The stator coil 11 adopts 240 turns of enameled wire with a wire diameter of 0.5 mm, and a built-in soft magnetic core. The material of the soft magnetic core is silicon steel sheet, and the magnetic permeability μ r = 2000.

[0039] The flywheel 13 adopts gray cast iron, the mass is 0.5-1.0 kg, and the rotational inertia is 0.01-0.03 kg.m 2

[0040] The valve core 2 is made of 42CrMo hardened steel, and the surface is quenched to HRC58-62. The guide sleeve 1 is made of tin bronze, and the hardness is HB180-220. The surface roughness of the two is less than or equal to 0.2 μm.

[0041] The valve core 2 is a stepped shaft structure, which is slidingly fitted in the inner hole of the guide sleeve 1. The radial gap between the two is 5 μm-10 μm, and a double-lip sealing structure 4 is arranged between the two.

[0042] The double-lip sealing structure 4 includes an inner lip-shaped ring and an outer lip-shaped ring. The inner lip-shaped ring is a contact type sealing made of fluorine rubber, and the outer lip-shaped ring is a non-contact type throttling sealing made of polytetrafluoroethylene. In this embodiment, the lip angle of the inner lip-shaped ring is 45°, a micron-level sealing band is formed under a 10 μm gap, and the static leakage is less than or equal to 5 mL / min.

[0043] Working process: normal mode: the reduction motor 12 drives the crank 9 to rotate, the crank 9 drives the sliding block 6 to move axially along the guide sleeve 8 through the connecting rod 7, thereby driving the valve core 2 to make reciprocating linear motion. In this process, the following formula is used:

[0044]

[0045] In the formula, θ represents the crank angle;

[0046] It can be seen that when l=5r, the peak speed appears near θ=73°, and 0.42 ms level hard switching is realized (5% of the period, corresponding to 8.3 ms period at 120 Hz frequency, and the transition time is less than or equal to 0.42 ms).

[0047] Energy storage stage: the valve core 2 is decelerated (the crank angle is rotated from 73° to 180°), the built-in permanent magnet of the flywheel cuts the stator coil 11, AC power is generated through electromagnetic induction (8 V induced electromotive force at 120 Hz speed), and the power is stored in the capacitor after rectification. The single switching recovery power is 5-8 W, and the energy recovery rate is greater than or equal to 30%. Until the encoder collects that the crank 9 stops rotating, the crank angle at this time is collected.

[0048] ​Fine-tuning stage: the encoder transmits the collected crank angle to the dual-ECU, compares it with the set crank angle, and according to the comparison result, energizes the stator coil 11 to drive the crank 9 by electromagnetic induction for fine-tuning, without changing the high-speed switching characteristics of the crank connecting rod mechanism, to realize high-precision angle fine-tuning at low speed.

[0049] Fault mode: when the dual-ECU detects an abnormal mechanical drive (crank 9 speed fluctuation > 5%), the first electromagnet is energized within 0.5 ms to directly drive the valve core 2 to move.

[0050] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application rather than limit it, although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand: it can still modify or equivalently replace the technical solutions of the present application, and these modifications or equivalent replacements also cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. An automobile air brake ABS solenoid valve spool assembly, comprising a spool slidingly arranged in a guide sleeve and a solenoid coil sleeved outside the spool, and a reset spring arranged at the end of the spool, characterized in that: The head end of the valve core is connected with the crank connecting rod driving mechanism, the crank connecting rod driving mechanism comprises a speed reducer motor, a crank connected with the output shaft of the speed reducer motor and a connecting rod hinged at one end with the crank, the other end of the connecting rod is hinged with the valve core through a sliding block after passing through a guide sleeve, and the guide sleeve is coaxially arranged with the valve core; Further comprising an electromagnetic coupling mechanism, the electromagnetic coupling mechanism comprises a flywheel arranged at the end of the crank shaft, a permanent magnet arranged inside the flywheel and a stator coil sleeved outside the flywheel, the stator coil is electrically connected with the energy storage unit through a rectifier bridge, and is used for recovering energy in the deceleration stage of the valve core.

2. The valve core assembly of an ABS solenoid valve for pneumatic brake of an automobile according to claim 1, characterized in that: The stator coil is also electrically connected with the output end of the double ECU through a PWM modulator, the input end of the double ECU is electrically connected with an encoder arranged on the crank, and is used for adjusting the crank angle according to the collection angle of the encoder by using the electromagnetic induction principle.

3. The valve core assembly of an ABS solenoid valve for pneumatic brake system of an automobile according to claim 2, characterized in that: The stator coil adopts high frequency response design, the response time is ≤0.1 ms, the current is ≤2 A, and ±10 N·m torque adjustment can be provided.

4. The valve core assembly of an ABS solenoid valve for pneumatic brake system of an automobile according to claim 1, characterized in that: The stator coil adopts 240 turns of enameled wire with a wire diameter of 0.5 mm, and a soft magnetic core is built in. The material of the soft magnetic core is silicon steel sheet, and the magnetic permeability .

5. The valve core assembly of an automotive pneumatic brake ABS solenoid valve according to claim 1, characterized in that: The flywheel is made of gray cast iron, and has a mass of 0.5-1.0 kg and a moment of inertia of 0.01-0.03 kg·m 2 .

6. The valve core assembly of an automotive pneumatic brake ABS solenoid valve according to claim 1, characterized in that: Valve core adopts 42CrMo hardened steel, surface quenching to HRC58-62, guide sleeve adopts tin bronze, hardness HB180-220, both cooperate surface roughness .

7. The valve core assembly of an ABS solenoid valve for pneumatic brake system of an automobile according to claim 1, characterized in that: The valve core is a stepped shaft structure, is slidingly fitted in the inner hole of the guide sleeve, the radial gap range of the two is 5μm-10μm, and a double-lip sealing structure is adopted between the two.

8. The valve core assembly of an ABS solenoid valve for pneumatic brake system of an automobile according to claim 7, characterized in that: The double-lip sealing structure comprises an inner lip-shaped ring and an outer lip-shaped ring, the inner lip-shaped ring adopts contact type sealing made of fluorine rubber, and the outer lip-shaped ring adopts non-contact throttling sealing made of polytetrafluoroethylene.

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