CN114718714B

CN114718714B - Autonomous variable fan

Info

Publication number: CN114718714B
Application number: CN202210458581.8A
Authority: CN
Inventors: 江扬帆; 彭斯
Original assignee: Dongfeng Male Thermal System Co ltd
Current assignee: Dongfeng Male Thermal System Co ltd
Priority date: 2022-04-24
Filing date: 2022-04-24
Publication date: 2023-05-26
Anticipated expiration: 2042-04-24
Also published as: CN114718714A

Abstract

The invention relates to an autonomous variable fan which comprises a fan blade assembly, a transmission mechanism and a control mechanism, wherein the transmission mechanism comprises a worm wheel and a worm meshed with the worm wheel for transmission, a motor drives the worm to rotate, and under the action of the transmission cooperation of the worm wheel and the worm, blades are driven to rotate, so that the blade inclination angle of the blades is changed within the range of 0-360 degrees. The function of unidirectional torque transmission of the worm and the worm gear is utilized, so that the stepping motor can realize the angle control of the worm through small torque and low cost, and further realize the precise control of the blade inclination angle. In the working process of the fan, the large torque generated by the axial force of the fan can be locked by the unidirectional torque transmission structure of the worm gear, so that the large torque can not influence the movement of the stepping motor, the influence of the torque on the precise control of the inclination angle of the fan blade is eliminated, and the precise control of the inclination angle of the fan blade is realized.

Description

Autonomous variable fan

Technical Field

The invention relates to a cooling system of an engine of a commercial vehicle or a passenger vehicle, in particular to an autonomous variable fan.

Background

At present, in cooling systems on commercial vehicles and passenger vehicle platforms, a cooling fan of an engine is mainly a cooling fan formed by injection molding, wherein a main body of a fan blade is a nylon piece, and a framework of the fan blade is a metal insert and is used for being connected with power of the whole vehicle. Once the fan blade is designed and fixed, the appearance is fixed, and a plurality of parameters including the blade inclination angle are solidified, so that the fan blade cannot flexibly adjust the parameters according to different heat dissipation requirements of the engine, and cannot provide the most efficient cooling flow for the engine; when the heat dissipation requirement of the engine is low, the fan cannot reduce the consumption of the self power, so that the fuel consumption of the whole vehicle is increased; noise generated when the fan is operated cannot be effectively suppressed, and poor experience is given to terminal clients.

With the increasingly strict emission requirements of China six and seven, each engine factory needs to continuously improve the combustion efficiency of the engine, the fan is used as an accessory with the largest power consumption in a cooling system, the power consumption of the fan directly influences the combustion efficiency of the engine, and in order to reduce the emission, the design of the fan needs to ensure high air quantity and maintain low power consumption.

According to the design thought of traditional fan, after a fan design is finalized, parameters such as its fan structure, appearance, leaf inclination all can solidify, therefore the fan can't guarantee, and under different whole car road conditions, under the different engine operating mode, all keep high amount of wind, low-power consumption. Meanwhile, when the whole vehicle runs in a severe environment, the inclination angle of the traditional injection molding fan cannot be changed at will, and the fan cannot autonomously remove dust and sundries accumulated by the fan, so that dust is manually removed at intervals along with the continuous accumulation of dust, and the time and the labor are wasted, and the use rate of the whole vehicle is low; when the dust is too much, the unbalanced quantity of the fan is too large, the cooling effect of the fan is reduced, and the service life of the fan is also reduced; and wind noise generated when the fan rotates at a high speed by the traditional injection molding fan can also influence the driving experience of a driver.

Disclosure of Invention

In order to solve the problems, the invention provides the autonomous variable fan, which can change the blade inclination angle according to the working condition of an engine and the road condition of the whole vehicle.

The technical scheme adopted by the invention is as follows: an autonomous variable fan comprising a fan blade assembly comprising a plurality of blades, wherein: the motor is electrically connected with the control mechanism; the motor drives the worm to rotate, and under the action of the cooperation of worm and gear transmission, the blade is driven to rotate, and the blade inclination angle of the blade is changed within the range of 0-360 degrees.

Preferably, when the temperature of the engine compartment is detected to be lower than 65 ℃, the control mechanism controls the blade inclination angle alpha to move within the range of 0-15 degrees through the motor, and the fan blade operates at low power consumption, low noise and low air quantity.

Preferably, when the temperature of the engine compartment is detected to be 65-75 ℃, the control mechanism controls the blade inclination angle alpha to move within a range of 15-45 degrees through the motor, and at the moment, the air volume performance of the fan blade is adjusted to be medium power consumption, medium noise and medium air volume.

Preferably, when the temperature of the engine compartment body is detected to be more than 75 ℃, the control mechanism controls the blade inclination angle alpha to move within the range of 45-60 degrees through the motor, and at the moment, the air volume performance of the fan blade is adjusted to be high in power consumption, high in noise and large in air volume.

Preferably, the control mechanism is in communication connection with a CAN bus of the whole vehicle ECU, parameters of sensors in the whole vehicle thermal management system are read in real time, fan flow demand values of accessories of each cooling system are calculated respectively through relevant parameter input and an algorithm in the control mechanism, the maximum demand value is taken as a control parameter, the blade inclination angle of an output fan is calculated, and the blade inclination angle is controlled through a PWM phase signal so as to meet the air quantity flow demand; the flow rate sensor detects the flow rate of the current fan and converts the flow rate into a real-time flow rate value through internal processing of the control mechanism; the real-time flow value is fed back into the control mechanism as a feedback value, and the control mechanism achieves closed-loop control of the blade inclination angle through PID control by comparing the required flow with the flow feedback value.

Preferably, at the moment of starting the fan, the control mechanism controls the blade inclination angle alpha of the blade to move within the range of-15 degrees to-60 degrees through the motor, and the fan is in a self-dedusting mode.

Preferably, the motor is a stepping motor, the torque is kept to be 0.24-5 Nm, the clamping torque is more than 0.24Nm, and the single-step stepping angle range is 0.75-2 degrees.

Preferably, the gear teeth of the worm wheel are 28-80, the tooth surface outer diameter is 30-100 mm, the tooth surface width is 10-30 mm, and the worm wheel is made of cast tin bronze, aluminum iron bronze or cast iron; the worm is made of 40Cr hardened HRC 50-55, the number of heads of the worm is 1-4, the pressure angle is 20 degrees, the diameter of the reference circle is 30-100 mm, and the modulus is 1-3.

The beneficial effects obtained by the invention are as follows: the invention uses the function of unidirectional torque transmission of the worm and the worm gear, ensures that the stepping motor can realize the angle control of the worm through small torque and low cost, and further realizes the accurate control of the blade inclination angle. In the working process of the fan, the large torque generated by the axial force of the fan can be locked by the unidirectional torque transmission structure of the worm gear, so that the large torque can not influence the movement of the stepping motor, the influence of the torque on the precise control of the inclination angle of the fan blade is eliminated, and the precise control of the inclination angle of the fan blade is realized. Compared with the existing fan, the fan has the following advantages:

1. the stepping motor is combined with the worm gear and the worm to be connected with the fan blade shaft, so that the inclination angle of the fan blade can be intelligently changed, the fan always works in the optimal condition, namely the state of highest output flow, lowest power consumption and lowest noise, the oil saving property of the whole car can be improved, and the satisfaction degree of a terminal customer can be improved, for example, when the heat dissipation load of the whole car is lower, the inclination angle of the fan blade is adjusted, the flow rate of the fan is reduced, the noise of the fan is reduced, a comfortable and quiet driving environment is provided for drivers and passengers, and the noise pollution is reduced; when the heat load of the whole vehicle is high, the flow of the fan can be improved, the efficiency of the fan is improved, and the oil consumption can be reduced;

2. the self-dedusting function of the newly added fan can effectively prolong the service life of the fan;

3. the fan has the capabilities of autonomous control and whole vehicle linkage, and performs closed-loop control through an internally integrated temperature sensor and a wind speed sensor when the fan is not connected to a whole vehicle CAN; when the fan sensor is connected to the whole CAN network, the fan sensor still works, other thermal parameters are derived from the whole CAN network, and the control logic of the fan sensor CAN be more accurate.

Drawings

FIGS. 1-2 are schematic structural views of the present invention;

FIG. 3 is a schematic diagram of the connection of a blade, worm gear and stepper motor;

FIG. 4 is a schematic diagram of the control mechanism mounted on a fan;

FIG. 5 is a control logic diagram of the present invention;

FIG. 6 is a schematic diagram of a portion of the PID control mechanism of the present invention;

FIG. 7 is a schematic diagram of a portion of the hardware circuitry of the control mechanism of the present invention;

FIG. 8 is a fan performance diagram;

wherein: 1. a fan blade assembly; 11. a fan blade; 12. an insert; 2. a transmission mechanism; 21. an output shaft of the stepping motor; 22. a worm gear; 23. a worm shaft bearing; 24. a worm gear; 25. a stepping motor; 26. a step motor fixing bolt; 27. a worm gear shaft bearing; 28. a fan connecting shaft; 3. a control mechanism; 31. a fan ECU controller; 32. the CAN bus is connected with the wiring harness; 33. a fan ECU signal output line; 34. a slip ring; 4. A connecting plate; 5. A wind speed sensor; 6. the fan is connected with the positioning hole; 7. and fixing the clamp for the wire harness.

Description of the embodiments

The invention will be further described with reference to the drawings and the specific examples.

1-3, the autonomous variable fan of the present invention may be separately coupled to an engine output crankshaft or pulley for use in an engine cooling system; the cooling system can also be connected with an electric motor in the new energy vehicle and used for a cooling system of the new energy vehicle. The fan comprises a fan blade assembly 1, a transmission mechanism 2 and a control mechanism 3, wherein the fan blade assembly 1 is composed of a plurality of blades, each blade comprises a plastic fan blade 11 and a metal insert 12, the root of each fan blade 11 is fixed with one end of each insert 12 in a riveting mode, the other end of each insert 12 is connected with the transmission mechanism 2 through a fan connecting shaft 3.3, rotation at any angle can be achieved, the blade inclination angle alpha of each fan blade is changed, the changed angle range is 0-360 degrees, and the edge of each fan blade is 200-500 mm away from the rotation center. The change of the blade inclination angle can realize the change of static pressure, flow and power of the fan under the same rotating speed so as to match the characteristic requirements of the fan blades under different whole-vehicle working conditions. The number of the blades of the fan blade assembly 1 can be selected according to the air quantity required by customers, and the number of the blades can be selected from 2-13 blades as a preferable choice.

As shown in fig. 3, the transmission mechanism 2 adopts a worm and gear transmission structure, and comprises a stepping motor 25, a worm wheel and a worm, a worm gear 24 is meshed with a worm gear 22 for transmission, two ends of a worm gear shaft are arranged in a gear box through worm gear shaft bearings 27, and the worm gear shaft is fixedly connected with a fan connecting shaft 13; the two ends of the worm gear shaft are arranged in the gear box through worm shaft bearings 23, the worm gear shaft is fixedly connected with a stepping motor output shaft 21 (the worm gear shaft and the stepping motor output shaft can be in coaxial design), the gear box is fixed with the connecting plate 4, and the stepping motor 25 is arranged on the connecting plate 4 through a stepping motor fixing bolt 26. After receiving the control signal, the stepper motor 25 rotates according to a certain stepping angle, so that the worm shaft rotates by the same angle, and further drives the worm gear 24 fixed with the blade, thereby realizing the controllability of the blade inclination angle alpha. The connecting plate 4 is provided with an air speed sensor 5, a temperature sensor, a fan connecting and positioning hole 6 and a wire harness fixing clamp 7.

The stepper motor 25 may be a two-phase or multi-phase stepper motor, and due to the design of worm gear transmission, the required torque holding range of the stepper motor is lower than 0.24-5 Nm, the clamping torque is greater than 0.24Nm, the single-step pitch angle range is 0.75-2 °, the motor size is 50 x 50mm, the applicable voltage range is 5-48 v, the rated current is <2A, and the rated power is <15W.

In one embodiment, the worm gear 24 has a tooth number range of 28-80, a tooth surface outer diameter of 30-100 mm and a tooth surface width of 10-30 mm, and is made of cast tin bronze, aluminum iron bronze or cast iron; the worm is made of 40Cr hardened HRC 50-55, the number of heads of the worm is 1-4, the pressure angle is 20 degrees, the diameter of the reference circle is 30-100 mm, and the modulus is 1-3. The material of the connecting plate 4 is S460MC, the surface is galvanized, the thickness is 4-6 mm, and the diameter range of the outer ring is 200-300 mm; the fixed diameter range of the inner ring is 100-180 mm.

The control mechanism 3 of the invention CAN be connected with the vehicle VECU, reads the sensor data related to the cooling system through the vehicle CAN bus, and is used as an input signal to be transmitted to the fan, and calculates the current most suitable blade inclination angle of the fan through an internal algorithm; then driving a stepping motor beside the single fan blade to drive the worm to be connected, and then starting the rotation of the worm wheel and the gear; the worm gear shaft is connected with the fan blade shaft, so that the blade inclination angle of the fan is changed to realize the function of variable flow, efficiency and power consumption.

As shown in fig. 4, the control mechanism 3 of the present invention is integrally fixed on the connecting plate 4, and is connected with an integral wire harness to transmit an electric signal in the form of a slip ring 34, and does not participate in the rotation of the fan. The control mechanism 3 comprises a fan ECU controller 31, a CAN bus connection harness 32, a PCB circuit board provided with an ECU, a fan ECU signal output line 33 and a temperature sensor, wherein the fan ECU signal output line 33 and the temperature sensor are output to the execution mechanism, and the fan ECU controller 31 is fixed with the connecting plate 4 through bearing fit and does not participate in the rotation motion of a fan; the CAN bus connection harness 32 CAN be used for data interaction between the fan ECU controller 31 and the whole vehicle ECU, and reads sensor parameters related to a thermal system.

The PCB circuit board on which the ECU is arranged comprises the following modules: MCU computing element, power supply module, step motor drive module, circuit protection module, signal acquisition and conversion module, CAN module etc.. The signal acquisition and conversion module can convert the information transmitted by the air volume sensor into an electric signal which can be processed by the MCU computing unit and is used as an input signal; the CAN module CAN transmit the sensor parameters acquired from the whole vehicle to the MCU computing unit through a CAN line; the power supply module can provide a direct current power supply with temperature for the control mechanism, and the direct current power supply can output 5V direct current as a preferential output; the stepping motor driving module is used for sending a phase driving signal and driving the stepping motor 25 of each fan blade accessory so as to control the blade inclination angle of the fan blade; the circuit protection module integrates protection strategies for the ECU, including but not limited to: the stepping motor is locked and protected, overcurrent and overvoltage protected, high-temperature protected and locked and protected; the signal acquisition and conversion module can convert signals acquired by an external sensor, such as a temperature signal and a wind speed signal, into level signals acceptable by the MCU chip; the MCU computing unit integrates core intelligent control strategy logic inside, so that three fan working modes can be realized: the intelligent control system comprises a fan independent variable performance mode, a fan combined whole car intelligent accurate control mode and a fan self-dedusting mode.

As shown in fig. 5, the control logic of the present invention has 2 types: autonomous control and joint control.

Fan autonomous variable performance mode: the temperature sensor of the control mechanism 3 is used for collecting the ambient temperature around the fan in real time, when the temperature of the engine cabin is detected to be lower than 65 ℃, the phase PWM signal output to the stepping motor is calculated through an MCU algorithm, the inclination angle alpha of the fan blade is controlled to be within the range of 0-15 degrees, and the fan blade runs at low power consumption, low noise and low air quantity; when the temperature of the engine compartment is detected to be 65-75 ℃, the inclination angle of the fan blade is controlled to be 15-45 degrees through a fan MCU algorithm. At this time, the air volume performance of the fan blade is adjusted to be middle power consumption, middle noise and middle air volume; when the temperature of the engine cabin body is detected to be more than 75 ℃, the inclination angle of the fan blade is controlled to be 45-60 degrees. At this time, the air volume performance of the fan blade is adjusted to be high in power consumption, high in noise and large in air volume.

As shown in fig. 6, the intelligent precise control mode (joint control) of the fan joint whole vehicle is: the control mechanism is in communication connection with a CAN bus of the whole vehicle ECU, and reads parameters of each sensor in the whole vehicle thermal management system in real time, and the parameters are specifically but not limited to an engine water inlet temperature, an intercooler air inlet pressure, an environment temperature, an air conditioner compressor pressure switch, a retarder switch and an oil cooler switch. And calculating fan flow demand values of accessories of each cooling system respectively through relevant parameter input and an internal algorithm of a control mechanism, taking the maximum demand value as a control parameter, calculating and outputting a blade inclination angle of the fan, and controlling the blade inclination angle through PWM phase signals so as to meet the air volume flow demand. The flow rate sensor can detect the current flow rate of the fan and convert the current flow rate into a real-time flow rate value through internal processing of the control mechanism. The real-time flow value is fed back into the control mechanism as a feedback value, and the control mechanism achieves closed-loop control of the blade inclination angle through PID control by comparing the required flow with the flow feedback value.

As shown in FIG. 7, the self-dedusting mode of the fan occurs at the moment of starting the fan, the inclination angle alpha of the fan blade is adjusted to be-15 to-60 degrees through the control mechanism, so that the air suction and the air blowing reversal of the fan are realized, dust attached to the surface of the fan blade can be removed, and when the dedusting mode of the fan is maintained for 1-3 min, the dedusting logic function is closed.

The fan MCU controller of the invention is internally provided with three control strategy logics: a fan autonomous intelligent control strategy, a fan combined whole vehicle cooperative control strategy and a fan dust removal strategy; the PWM driving module is used as an MCU to output to a signal generator for controlling the phase of the stepping motor; the protection module is used as high temperature or MCU failure protection, and the default output PWM signal controls the stepping motor to be in default phase after the MCU fails, so that the fan is ensured to have a large-flow heat dissipation mode, and the basic heat dissipation requirement of the whole vehicle is solved. The cabin environment temperature sensor is used for collecting cabin temperature when the fan is controlled autonomously.

The working principle of the invention is as follows: the control of the tilt angle of the failure fan blade of the stepping motor is controlled by the signal acquisition of the sensors of the whole car thermal management system and the internal calculation of the air volume demand of the lowest power consumption and the lowest noise, so that the output flow, power consumption, noise and efficiency of the fan blade are changed. Meanwhile, the inclination angle of the fan blade is controlled by a wind speed sensor in real time in a closed loop PID mode, so that the accurate control of the air quantity of the fan is met. And further, the output of the fan air volume under the lowest power consumption and the lowest noise is achieved.

The fan surface of the invention is provided with the wind speed sensor, the wind speed of the fan blade surface can be collected in real time and fed back to the ECU in the fan, and the ECU can carry out PID compensation on the output blade inclination angle according to the feedback value to form a closed-loop control design. By means of closed-loop control, the fan blade has the capacity of controlling flow with higher precision, and the power consumption and noise of the fan can be effectively reduced according to the working condition of the whole automobile. The fan provided by the invention also has a dust removal mode, so that the blade inclination angle of the fan can be moved in a negative number angle, the conversion between blowing and induced draft is realized under the condition that the fan rotates in the same direction, and dust and sundries attached to the surface of the blade of the fan can be removed rapidly.

The invention skillfully uses the unidirectional torque transmission function of the worm and the worm gear, ensures that the stepping motor can realize the angle control of the worm through small torque and low cost, the rotation of the worm can drive the worm gear to perform angle positioning, the worm gear is fixed with the fan blade connecting shaft, and the blade inclination angle of the plastic blade of the fan can be accurately controlled. In the working process of the fan, the large torque generated by the axial force of the fan can be locked by the unidirectional torque transmission structure of the worm gear, so that the large torque can not influence the movement of the stepping motor, the influence of the torque on the precise control of the inclination angle of the fan blade is eliminated, and the precise control of the inclination angle of the fan blade is realized.

With reference to fig. 8, calculated by the design model: taking a 400-600 horsepower fuel vehicle as an example, the diameter of the blade of the matched fan blade is 750mm. The power saving and noise reduction of the fan of the present patent were calculated for example at a fan speed ratio of 1.38 at 1900rpm at the fuel engine power point. Fan speed is 1900 x 1.38=2622 rpm; the conventional injection molded blades drive the fan at a speed of 2622rpm at least 35kW. As shown in the drawing, when the load of the whole vehicle heat system is lower, the air quantity is reduced by 20% by calculating through the fan ECU, and the power consumption of the fan is reduced to 20kW under the working condition by changing the inclination angle of the fan blade, so that the power consumption of 17kW under the working condition is saved. At the same time, the noise is reduced from 115db to 109db, and the noise level is reduced by 6db. The fan of the fuel-efficient engine consumes power and reduces fan noise.

The foregoing has shown and described the basic principles and main structural features of the present invention. The present invention is not limited to the above examples, and various changes and modifications may be made therein without departing from the spirit and scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. An autonomous variable fan comprising a fan blade assembly comprising a plurality of blades, wherein: the motor is electrically connected with the control mechanism; the motor drives the worm to rotate, and under the action of the transmission cooperation of the worm and the gear, the blade is driven to rotate, so that the blade inclination angle of the blade is changed within the range of 0-360 degrees;

when the temperature of the engine compartment is detected to be lower than 65 ℃, the control mechanism controls the blade inclination angle alpha of the blade to move within the range of 0-15 degrees through the motor, and the fan blade runs at low power consumption, low noise and low air quantity;

when the temperature of the engine compartment is detected to be 65-75 ℃, the control mechanism controls the blade inclination angle alpha of the blade to move within the range of 15-45 degrees through the motor, and the air volume performance of the fan blade is adjusted to be medium power consumption, medium noise and medium air volume;

when the temperature of the engine compartment body is detected to be more than 75 ℃, the control mechanism controls the blade inclination angle alpha of the blade to move within the range of 45-60 degrees through the motor, and the air volume performance of the fan blade is adjusted to be high in power consumption, high in noise and high in air volume; the control mechanism is in communication connection with a CAN bus of the whole vehicle ECU, parameters of sensors in the whole vehicle thermal management system are read in real time, fan flow demand values of accessories of each cooling system are calculated respectively through relevant parameter input and an algorithm in the control mechanism, the maximum demand value is taken as a control parameter, the blade inclination angle of an output fan is calculated, and the blade inclination angle is controlled through PWM phase signals so as to meet the air quantity and flow demand; the flow rate sensor detects the flow rate of the current fan and converts the flow rate into a real-time flow rate value through internal processing of the control mechanism; the real-time flow value is fed back into the control mechanism as a feedback value, and the control mechanism achieves closed-loop control of the blade inclination angle through PID control by comparing the required flow with the flow feedback value; at the moment of starting the fan, the control mechanism controls the blade inclination angle alpha of the blade to move within the range of-15 degrees to-60 degrees through the motor, and the fan is in a self-dedusting mode;

the motor adopts a stepping motor, the torque is kept to be 0.24-5 Nm, the clamping torque is more than 0.24Nm, and the single-step pitch angle range is 0.75-2 degrees.

2. The autonomous variable fan of claim 1, wherein: the gear tooth number range of the worm gear is 28-80, the tooth surface outer diameter is 30-100 mm, the tooth surface width is 10-30 mm, and the material is cast tin bronze, aluminum iron bronze or cast iron; the worm is made of 40Cr hardened HRC 50-55, the number of heads of the worm is 1-4, the pressure angle is 20 degrees, the diameter of the reference circle is 30-100 mm, and the modulus is 1-3.