CN111409616A - A new energy vehicle braking system - Google Patents

Abstract

The invention discloses a braking system for a new energy vehicle, which comprises a braking assembly, wherein the braking assembly comprises a braking pedal and a vacuum booster connected to the braking pedal, the vacuum booster comprises an inner air chamber and an outer air chamber, the inner air chamber and the outer air chamber are separated by a partition plate component arranged in the middle of the vacuum booster, a vacuum valve used for communicating the inner air chamber and the outer air chamber is arranged on the partition plate component, an air valve used for connecting the outer air chamber and the outside is also arranged on the vacuum booster, a pressure sensor component is also arranged in the vacuum booster, and the pressure sensor component is connected to a vehicle control unit. Through set up pressure sensor subassembly in new energy automobile's vacuum booster, to the pressure monitoring of specific area in the vacuum booster, in time transmit braking signal to vehicle control unit, and then ensure energy recuperation system's normal work.

Description

A new energy vehicle braking system

technical field

The invention relates to the technical field of automobile parts manufacturing, in particular to a braking system for a new energy vehicle.

Background technique

At present, new energy vehicles generally have energy recovery designs. Due to the requirements of braking regulations (such as GB 7258, GB 12676, etc.), when the driver steps on the pedal, most vehicle braking systems will work synchronously, driving the static friction material and the wheel high-speed rotating friction material to rub against each other, generating braking force, forcing Vehicle stopped. During this period, a large amount of vehicle kinetic energy or potential energy is converted into useless heat energy and wasted; when going down a long slope, this heat energy will affect the thermal stability of the vehicle brakes and cause the brakes to thermally decay. At present, the energy recovery design of new energy vehicles is generally connected with the brake light switch. , including the brake pedal brake valve, the brake pedal brake valve is connected to the air brake pipeline, and the air brake pipeline is connected to the service brake system to work; the brake pedal brake valve is also connected with a brake light switch and a brake Dynamic analog sensor; brake light switch, brake analog sensor and accelerator analog sensor are all connected to the vehicle controller VCU, and the vehicle controller VCU then passes through the motor controller MCU to the motor to generate power, slow braking, and energy recovery. To the power battery; a diaphragm type blocking control valve is arranged between the brake pedal brake valve and the pneumatic brake pipeline, and the diaphragm type blocking control valve is also connected to the vehicle controller VCU. This structure realizes various control states by connecting two identical blocking control valves in series in the two air brake pipeline circuits output by the brake pedal brake valve of the automobile, so as to integrate the air pressure braking energy feedback of the vehicle resources. However, when the signal transmission is carried out through the brake light switch as a signal medium, due to the different types of brake light switches of new energy vehicles on the market, some brake light switches, especially the brake light switches of the dual-circuit braking system, are working. During the process, there will be double-breaks, because the traditional pedal brake light switch only controls the switch of the brake light, so it has little effect. The new energy vehicle needs to use the brake light switch signal as the input of energy recovery. The appearance of double-break will cause abnormal signal input, cause the system to report an error, and then affect the normal operation of the energy recovery system. Therefore, for different structures of the braking system , a complete and feasible brake signal transmission system is required to provide timely feedback of brake signals to ensure the normal operation of new energy vehicles.

SUMMARY OF THE INVENTION

Aiming at the problem of abnormal braking signal transmission caused by the double-break situation in the process of signal transmission of the traditional brake light switch as a signal medium in the prior art, the present invention provides a braking system for a new energy vehicle. A pressure sensor component is installed in the vacuum booster of the car to monitor the pressure of a specific area in the vacuum booster, and transmit the braking signal to the vehicle controller in time to ensure the normal operation of the energy recovery system.

In order to achieve the above object, the present invention adopts the following technical solutions:

A brake system for a new energy vehicle includes a brake assembly, the brake assembly includes a brake pedal and a vacuum booster connected to the brake pedal, the vacuum booster includes an inner air chamber and an outer air chamber , the inner air chamber and the outer air chamber are separated by a baffle assembly arranged in the middle of the vacuum booster. The baffle assembly is provided with a vacuum valve for connecting the inner air chamber and the outer air chamber. An air valve for connecting the outer air chamber to the outside is also provided, and a pressure sensor assembly is also disposed in the vacuum booster, and the pressure sensor assembly is connected to the vehicle controller. The vacuum booster is also the mainstream brake boosting method for new energy vehicles. The electric vacuum pump of the vacuum booster is used for vacuuming, so that the driver can save effort when stepping on the brake pedal. The pressure sensor assembly is arranged inside the vacuum booster. When the internal pressure of the vacuum booster changes, the pressure sensor can identify the pressure change in time and transmit the pressure signal to the vehicle controller, so that the vehicle controller can accurately identify Braking signal to avoid the phenomenon that the signal of the brake light switch is discontinuous due to the asynchrony of the dual-circuit signal when the dual-circuit braking system is braking in the traditional technology. This phenomenon is called the double-break phenomenon. The double-break phenomenon may cause abnormal braking signals, which may cause problems in the judgment of the vehicle controller, because the setting of the pressure sensor can "insure" the brake light switch to ensure that the braking signal is transmitted to the vehicle controller in a timely and accurate manner. Guarantee the collaborative work of other systems of the vehicle. The pressure sensor can not only transmit the braking signal in real time, but also judge whether the vacuum booster leaks according to the opening and closing states of the vacuum valve and the air valve, so as to ensure the reliability of the braking device.

Preferably, the pressure sensor assembly is disposed on the side of the baffle assembly facing the outer air chamber. The pressure sensor is arranged on the side of the baffle assembly facing the outer air chamber, and can accurately measure the pressure of the outer air chamber. When the vacuum valve is opened, the air valve is closed, and there is no brake command, the vacuum booster is blocked from the outside atmosphere by the air valve, and the inner air chamber and the outer air chamber are communicated through the vacuum valve. At this time, the inner air chamber and the outer air are connected The chambers are all vacuum; when the driver steps on the brake pedal, the force from the brake pedal pushes the brake push rod forward to make the vacuum valve close, at this time the inner air chamber and the outer air chamber are isolated, and then the air valve opens, The outside air enters the outer air chamber and quickly balances the air pressure of the outer air chamber, so that the air pressure difference between the outer air chamber and the inner air chamber is formed. At this time, the pressure sensor reading changes according to the change of the outer air chamber pressure, and the vehicle controller is given real-time feedback. Ensure the accuracy of the braking signal; when the braking is over and the driver releases the brake pedal, the booster is slowly reset by the action of the return spring, first the air valve is closed to isolate the outer air chamber from the outside atmosphere, and then the vacuum valve Open, the inner air chamber and the outer air chamber are connected again, so that the vacuum is re-established. At this time, the diaphragm assembly returns to the non-working state, the vacuum booster is in the natural state, and the pressure sensor also returns to the working condition under the vacuum state.

Preferably, the pressure sensor assembly includes an absolute pressure sensor, the reading of the absolute pressure sensor is zero in a vacuum state, and the pressure value of the absolute pressure sensor can be accurately measured when the pressure in the outer air chamber changes. Because the air pressure of the outer air chamber changes to the range of vacuum - one atmospheric pressure, the absolute pressure sensor can avoid abnormal readings caused by the negative pressure generated by the ordinary pressure sensor due to vacuum, so that the vehicle controller cannot accurately accept the driver's driving intention. , resulting in a driving risk.

Preferably, the brake assembly provided with the hydraulic pipeline further includes an energy recovery system communicated with the vehicle controller, the energy recovery system is electrically connected to the pressure sensor, and the hydraulic pipeline is connected to the vehicle controller . The energy recovery system is a key system that distinguishes the electric vehicle from the traditional fuel-powered vehicle. When the vehicle is braking, the pressure sensor receives the pressure change in the outer air chamber and transmits the braking signal to the electric vehicle connected to the pressure sensor. An energy recovery system, when braking, part of its energy can be used to drive a power generation device in the energy recovery system, so that braking energy is converted into mechanical energy and then converted into electrical energy for storage.

Preferably, the energy recovery system includes a transmission device and a flywheel, and the flywheel is connected with the vehicle drive shaft through the transmission device. The transmission device is used to connect the hydraulic pipeline of the braking system. When the vehicle brakes, the hydraulic pipeline pressurizes the brake to complete the braking action. At this time, the vehicle brake determines whether to activate the energy recovery system according to the battery state. When energy recovery is required, the flywheel runs and participates in braking work, and converts part of the energy generated in the braking process into mechanical energy for motor operation, making the motor a power generator and charging the battery.

Preferably, the braking system further includes a brake light switch, the brake light switch is electrically connected with the energy recovery system, and the brake light switch is connected with the brake pedal. The brake light switch is used to turn on the brake light when the braking work is in progress. When the brake pedal is stepped on, the brake light switch is driven and works normally, and the brake light switch is electrically connected to the energy recovery system. The connection will also transmit the braking signal to the energy recovery system, so that the energy recovery system can still receive the braking signal without relying on the pressure sensor.

Preferably, the brake assembly further includes an alarm system connected with the vehicle controller, the alarm system is electrically connected with the pressure sensor, and the alarm system is linked with the brake pedal. The design of the pressure sensor can monitor the working conditions of the vacuum booster in real time. When the vacuum booster fails, especially the common air leakage phenomenon, the vehicle sensor can diagnose the vacuum booster according to the working parameters of the pressure sensor and the brake light switch. For example, when the brake pedal is not stepped on, the pressure sensor should read zero and the brake light switch should be turned off. If the pressure sensor reading changes or even changes to atmospheric pressure, it indicates that the vacuum booster is leaking. The vehicle controller will activate the alarm system to alert the driver that the vehicle is malfunctioning.

Advantageously, the alarm system includes a buzzer. The buzzer vibrates continuously and promptly reminds the driver of the failure of the vacuum booster. When the buzzer continues to work, the vehicle controller will forcefully activate the electronic parking system to maintain the normally open state, so as to ensure that the vehicle cannot continue to drive and cause potential safety hazards. .

Therefore, the present invention has the following beneficial effects: (1) by arranging a pressure sensor assembly in the vacuum booster of the new energy vehicle, the pressure of a specific area in the vacuum booster is monitored, and the braking signal is transmitted to the vehicle controller in time, In order to ensure the normal operation of the energy recovery system; (2) The brake light switch is electrically connected to the energy recovery system, and also transmits the braking signal to the energy recovery system, so that the energy recovery system can still receive the energy recovery system without relying on the pressure sensor. Braking signal; (3) The vehicle controller is connected to the pressure sensor and the brake light switch at the same time. Through the working conditions of the pressure sensor and the brake light switch, the start and stop of the energy recovery system can be accurately and timely controlled, and the vacuum booster can also be controlled. (4) The buzzer in the alarm system will continue to vibrate when the vacuum booster fails and force the electronic parking system to be turned on, the auxiliary braking is completed and the driver cannot be prevented when the vacuum booster fails. Continue to drive the vehicle normally and improve road traffic safety.

Description of drawings

FIG. 1 is a schematic structural diagram of the present invention.

FIG. 2 is a flow chart of the operation of the present invention.

In the picture: 1. Brake assembly, 101, Vehicle controller, 11, Brake pedal, 2, Vacuum booster, 21, Inner air chamber, 22, Outer air chamber, 23, Partition assembly, 3, Vacuum Valve, 4. Air valve, 5. Pressure sensor assembly, 51. Absolute pressure sensor, 6. Energy recovery system, 7. Brake light switch, 8. Alarm system.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Examples of such embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to explain the present invention and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the terms "center", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", " The orientations or positional relationships indicated by vertical, horizontal, top, bottom, inside, and outside are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying It is described, rather than indicated or implied, that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as limiting the invention.

In the present invention, unless otherwise expressly specified and limited, the terms "installed", "connected", "connected", "fixed" and other terms should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection , or integrated; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of the two elements or the interaction relationship between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

Example

As shown in Figures 1 and 2, a braking system for a new energy vehicle includes a brake assembly 1, the brake assembly includes a brake pedal 11 and a vacuum booster 2 connected to the brake pedal. The vacuum booster includes an inner air chamber 21 and an outer air chamber 22. The inner air chamber and the outer air chamber are separated by a baffle assembly 23 arranged in the middle of the vacuum booster. The baffle assembly is provided with a connection for communicating the inner air chamber. and the vacuum valve 3 of the outer air chamber, the vacuum booster is also provided with an air valve 4 for connecting the outer air chamber and the outside world, the vacuum booster is also provided with a pressure sensor group 5, and the pressure sensor assembly is connected in the vehicle controller 101 . The vacuum booster is also the mainstream brake boosting method for new energy vehicles. The vacuum pump of the vacuum booster is used for vacuuming, so that the driver can save effort when stepping on the brake pedal. The pressure sensor assembly is arranged inside the vacuum booster. When the internal pressure of the vacuum booster changes, the pressure sensor can identify the pressure change in time and transmit the pressure signal to the vehicle controller, so that the vehicle controller can accurately identify Braking signal, to avoid the phenomenon that the signal of the brake light switch 7 is discontinuous due to the non-synchronization of the dual-circuit signal when the dual-circuit braking system is braking in the traditional technology. This phenomenon is called the double-break phenomenon. The double-break phenomenon may cause abnormal braking signals, which may cause problems in the judgment of the vehicle controller, because the setting of the pressure sensor can "insure" the brake light switch to ensure that the braking signal is transmitted to the vehicle controller in a timely and accurate manner. Guarantee the collaborative work of other systems of the vehicle. The pressure sensor can not only transmit the braking signal in real time, but also judge whether the vacuum booster leaks according to the opening and closing states of the vacuum valve and the air valve, so as to ensure the reliability of the braking device. The pressure sensor is arranged on the side of the baffle assembly facing the outer air chamber, and can accurately measure the pressure of the outer air chamber. When the vacuum valve is opened, the air valve is closed, and there is no brake command, the vacuum booster is blocked from the outside atmosphere by the air valve, and the inner air chamber and the outer air chamber are communicated through the vacuum valve. At this time, the inner air chamber and the outer air are connected The chambers are all vacuum; when the driver steps on the brake pedal, the force from the brake pedal pushes the brake push rod forward to make the vacuum valve close, at this time the inner air chamber and the outer air chamber are isolated, and then the air valve opens, The outside air enters the outer air chamber and quickly balances the air pressure of the outer air chamber, so that the air pressure difference between the outer air chamber and the inner air chamber is formed. At this time, the pressure sensor reading changes according to the change of the outer air chamber pressure, and the vehicle controller is given real-time feedback. Ensure the accuracy of the braking signal; when the braking is over and the driver releases the brake pedal, the booster is slowly reset by the action of the return spring, first the air valve is closed to isolate the outer air chamber from the outside atmosphere, and then the vacuum valve Open, the inner air chamber and the outer air chamber are connected again, so that the vacuum is re-established. At this time, the diaphragm assembly returns to the non-working state, the vacuum booster is in the natural state, and the pressure sensor also returns to the working condition under the vacuum state. The pressure sensor assembly includes an absolute pressure sensor 51. In this embodiment, the signal of the absolute pressure sensor used is MLX90808, which is small in size and high in sensitivity, and is suitable for being installed on the baffle assembly of the vacuum booster. The absolute pressure sensor is provided with a vacuum chamber inside, and takes vacuum as the measurement standard, so the reading in the vacuum state is zero, and the pressure value can be accurately measured when the pressure in the outer air chamber changes. Because the air pressure of the outer air chamber changes to the range of vacuum - one atmospheric pressure, the absolute pressure sensor can avoid abnormal readings caused by the negative pressure generated by the ordinary pressure sensor due to vacuum, so that the vehicle controller cannot accurately accept the driver's driving intention. , resulting in a driving risk.

The brake assembly provided with the hydraulic pipeline further includes an energy recovery system 6 which is communicated with the vehicle controller, the energy recovery system is electrically connected with the pressure sensor, and the hydraulic pipeline is connected with the vehicle controller. The energy recovery system is a key system that distinguishes the electric vehicle from the traditional fuel-powered vehicle. When the vehicle is braking, the pressure sensor receives the pressure change in the outer air chamber and transmits the braking signal to the electric vehicle connected to the pressure sensor. An energy recovery system, when braking, part of its energy can be used to drive a power generation device in the energy recovery system, so that braking energy is converted into mechanical energy and then converted into electrical energy for storage. The energy recovery system includes a transmission device and a flywheel, and the flywheel is connected with the vehicle drive shaft through the transmission device. The transmission device is used to connect the hydraulic pipeline of the braking system. When the vehicle brakes, the hydraulic pipeline pressurizes the brake to complete the braking action. At this time, the vehicle brake determines whether to activate the energy recovery system according to the battery state. When energy recovery is required, the flywheel runs and participates in braking work, and converts part of the energy generated in the braking process into mechanical energy for motor operation, making the motor a power generator and charging the battery.

The braking system further includes a brake light switch that is electrically connected to the energy recovery system and that is connected to the brake pedal. The brake light switch is used to turn on the brake light when the braking work is in progress. When the brake pedal is stepped on, the brake light switch is driven and works normally, and the brake light switch is electrically connected to the energy recovery system. The connection will also transmit the braking signal to the energy recovery system, so that the energy recovery system can still receive the braking signal without relying on the pressure sensor. The brake assembly further includes an alarm system 8 connected to the vehicle controller, the alarm system is electrically connected to the pressure sensor, and the alarm system is linked to the brake pedal. The design of the pressure sensor can monitor the working conditions of the vacuum booster in real time. When the vacuum booster fails, especially the common air leakage phenomenon, the vehicle sensor can diagnose the vacuum booster according to the working parameters of the pressure sensor and the brake light switch. For example, when the brake pedal is not stepped on, the pressure sensor should read zero and the brake light switch should be turned off. If the pressure sensor reading changes or even changes to atmospheric pressure, it indicates that the vacuum booster is leaking. The vehicle controller will activate the alarm system to alert the driver that the vehicle is malfunctioning. The alarm system includes a buzzer. The buzzer vibrates continuously and promptly reminds the driver of the failure of the vacuum booster. When the buzzer continues to work, the vehicle controller will forcefully activate the electronic parking system to maintain the normally open state, so as to ensure that the vehicle cannot continue to drive and cause potential safety hazards. .

In addition to the above-mentioned embodiments, within the scope disclosed in the claims and description of the present invention, the technical features of the present invention can be re-selected and combined to form new embodiments, which are all without creative work by those skilled in the art Therefore, these embodiments of the present invention that are not described in detail should also be regarded as specific embodiments of the present invention and fall within the protection scope of the present invention.

Claims (8)

1. A braking system for a new energy vehicle, comprising a brake assembly (1), the brake assembly (1) comprising a brake pedal (11) and a vacuum booster connected to the brake pedal (11) (2), the vacuum booster system includes an inner air chamber (21) and an outer air chamber (22), and the inner air chamber (21) and the outer air chamber (22) pass through the air chamber provided in the middle of the vacuum booster (2). The baffle assembly (23) is separated, the baffle assembly (23) is provided with a vacuum valve (3) for communicating the inner air chamber (21) and the outer air chamber (22), and the vacuum booster (2) is provided with a vacuum valve (3). An air valve (4) for connecting the outer air chamber (22) with the outside is also provided, wherein the vacuum booster (2) is further provided with a pressure sensor assembly (5), the pressure sensor assembly (5) ) is connected to the vehicle controller (101). 2 . The braking system for a new energy vehicle according to claim 1 , wherein the pressure sensor assembly ( 5 ) is arranged on the side of the partition plate assembly ( 23 ) facing the outer air chamber ( 22 ). 3 . 3 . The braking system for a new energy vehicle according to claim 2 , wherein the pressure sensor assembly ( 5 ) comprises an absolute pressure sensor ( 51 ). 4 . 4 . The braking system for a new energy vehicle according to claim 1 , wherein the braking assembly ( 1 ) provided with the hydraulic pipeline further comprises a braking system that communicates with the vehicle controller ( 101 ). 5 . An energy recovery system (6), the energy recovery system (6) is electrically connected with the pressure sensor assembly (5), and the hydraulic pipeline is connected with the vehicle controller (101). 5 . The braking system for a new energy vehicle according to claim 4 , wherein the energy recovery system ( 6 ) comprises a transmission device and a flywheel, and the flywheel is connected to the vehicle drive shaft through the transmission device. 6 . 6. The braking system for a new energy vehicle according to any one of claims 1-5, wherein the braking assembly (1) further comprises a brake light switch (7), the braking The moving light switch (7) is electrically connected with the energy recovery system (6), and the brake light switch (7) is connected with the brake pedal (11). 7. The braking system for a new energy vehicle according to any one of claims 1-5, wherein the braking assembly (1) further comprises an alarm connected to the vehicle controller (101). A system (8), the alarm system (8) is electrically connected to the pressure sensor assembly (5), and the alarm system (8) is connected to the brake pedal (11). 8 . The braking system for a new energy vehicle according to claim 7 , wherein the alarm system ( 8 ) comprises a buzzer. 9 .

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