CN114718714A

CN114718714A - Autonomous variable fan

Info

Publication number: CN114718714A
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: 2022-07-08
Anticipated expiration: 2042-04-24
Also published as: CN114718714B

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 turbine and a worm meshed with the turbine for transmission, a motor drives the worm to rotate, under the transmission and matching action of the turbine and the worm, blades are driven to rotate, and the blade inclination angle of each blade is changed within the range of 0-360 degrees. The function of unidirectional torque transmission of the worm and the worm wheel is utilized, so that the angle control of the worm can be realized through the small torque and the low cost of the stepping motor, and the accurate control of the blade inclination angle of the blade is further realized. In the working process of the fan, the large torque generated by the axial force of the fan can be locked by the one-way torque transmission structure of the worm gear and worm, so that the large torque cannot influence the movement of the stepping motor, the influence of the torque on the accurate control of the inclination angle of the fan blade is eliminated, and the accurate control of the inclination angle of the fan blade is realized.

Description

Autonomous variable fan

Technical Field

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

Background

At present, in a cooling system on platforms of commercial vehicles and passenger vehicles, 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 per se 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 lower, the fan cannot reduce the power consumption per se, and the fuel consumption of the whole vehicle is increased; the noise generated when the fan operates cannot be effectively suppressed, and poor experience is provided for terminal customers.

With the increasingly strict emission requirements of the sixth and seventh countries, the combustion efficiency of the engine needs to be continuously improved in each engine plant, the combustion efficiency of the engine is directly affected by the power consumption of the fan as an accessory with the largest power consumption in the cooling system, and in order to reduce the emission, the design of the fan needs to ensure high air volume and maintain low power consumption.

According to the design thinking of traditional fans, after a fan design is finalized, its fan structure, appearance, blade inclination isoparametric all can solidify, therefore the fan can't be guaranteed, and under different whole car road conditions, different engine operating modes, all keep high amount of wind, low-power consumption. Meanwhile, when the whole vehicle runs in a severe environment, the blade inclination angle of the traditional injection molding fan cannot be changed at will, dust and sundries accumulated by the fan cannot be removed automatically by the blades, and along with the continuous accumulation of the dust, the dust needs to be manually removed at intervals, so that time and labor are wasted, and the utilization rate of the whole vehicle is low; when the dust is too much, the unbalance of the fan is too large, the cooling effect of the fan is reduced, and the service life of the fan is also reduced; the wind noise generated by the conventional injection molding fan when the fan rotates at a high speed also influences the driving experience of a driver.

Disclosure of Invention

In order to solve the above problems, the present invention provides an autonomous variable fan, in which the blade inclination angle is changed according to the change of the engine operating condition and the road condition of the entire 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, characterized in that: the blade-mounted motor is characterized by further comprising a transmission mechanism and a control mechanism, wherein the transmission mechanism comprises a worm wheel and a worm which is in meshing transmission with the worm wheel, the worm wheel is fixedly connected with the blades, the worm is connected with an output shaft of the motor, and the motor is electrically connected with the control mechanism; the motor drives the worm to rotate, and under the effect of the transmission fit of the worm and gear, 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 cabin 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 operates at low power consumption, low noise and low air volume.

Preferably, when the temperature of the engine cabin 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.

Preferably, when the temperature of the engine cabin is detected to be greater 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 large in air volume.

Preferably, the control mechanism is in communication connection with a CAN bus of a whole vehicle ECU, parameters of sensors in a whole vehicle thermal management system are read in real time, fan flow required values of accessories of each cooling system are respectively calculated through related parameter input and an internal algorithm of the control mechanism, the maximum required value is taken as a control parameter, a blade inclination angle of an output fan is calculated, and the blade inclination angle is controlled through a PWM phase signal to meet the air flow requirement; the flow velocity sensor detects the current flow velocity of the fan, and the current flow velocity is converted into a real-time flow value through the internal processing of the control mechanism; the real-time flow value is fed back to 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 to move within a 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 holding torque is 0.24-5 Nm, the clamping torque is greater than 0.24Nm, and the stepping angle of a single step is 0.75-2 degrees.

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

The beneficial effects obtained by the invention are as follows: the invention utilizes the function of unidirectional torque transmission of the worm and gear to ensure that the stepping motor can realize the angle control of the worm through small torque and low cost, thereby realizing the accurate control of the blade inclination angle of the blade. In the working process of the fan, the large torque generated by the axial force of the fan can be locked by the one-way torque transmission structure of the worm gear and worm, so that the large torque cannot influence the movement of the stepping motor, the influence of the torque on the accurate control of the inclination angle of the fan blade is eliminated, and the accurate control of the inclination angle of the fan blade is realized. Compare and have following advantage in current fan:

1. the stepping motor is combined with the worm gear and the worm gear to be connected with the fan blade shaft, so that the inclination angle of the fan blade can be intelligently changed, the fan can always work in the optimal condition, namely, the states of highest output flow, lowest power consumption and lowest noise are realized, the fuel saving performance of the whole vehicle and the satisfaction degree of a terminal customer can be improved, for example, when the heat dissipation load of the whole vehicle is lower, the inclination angle of the fan blade is adjusted, the flow 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 fan is additionally arranged, so that the service life of the fan can be effectively prolonged;

3. the fan has the capability of autonomous control and whole vehicle linkage, and when the fan is not connected to a whole vehicle CAN network, closed-loop control is performed through an internally integrated temperature sensor and a wind speed sensor; when the fan sensor is connected to the whole vehicle CAN network, the fan sensor still works, other thermal parameters are derived from the whole vehicle 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 view of the connection of the blade, worm gear and stepper motor;

FIG. 4 is a schematic view of the control mechanism mounted to the fan;

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

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

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

FIG. 8 is a fan performance graph;

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 turbine gear; 25. a stepping motor; 26. a stepping motor fixing bolt; 27. a turbine gear shaft bearing; 28. a fan coupling shaft; 3. a control mechanism; 31. a fan ECU controller; 32. the CAN bus is connected with a wire harness; 33. a fan ECU signal output line; 34. a slip ring; 4. a coupling plate; 5. a wind speed sensor; 6. the fan is connected with the positioning hole; 7. the clamp is fixed to the pencil.

Detailed Description

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

With reference to fig. 1-3, the autonomous variable fan of the present invention can be used in an engine cooling system by being separately connected to the engine output crankshaft or pulley; the cooling system can also be connected with a motor in the new energy vehicle and used for the 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 the fan blade 11 is fixed with one end of the insert 12 in a riveting mode, the other end of the insert 12 is connected with the transmission mechanism 2 through a fan connecting shaft 3.3, rotation at any angle can be realized, the blade inclination angle alpha of the fan blade is further changed, the changed angle range is 0-360 degrees, and the edge of the 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 to match the characteristic requirements of the fan blades under different working conditions of the whole vehicle. The number of the blades of the fan blade assembly 1 can be selected according to the air volume required by a customer, and the blades can be selected from 2-13 blades as preferred.

Referring to fig. 3, the transmission mechanism 2 adopts a worm gear and worm transmission structure, and includes a step motor 25, a worm gear and a worm, a worm gear 24 is in mesh transmission with the worm gear 22, two ends of a worm gear shaft are arranged in the gear box through a worm gear shaft bearing 27, and the worm gear shaft is fixedly connected with the fan coupling shaft 13; two ends of a worm gear shaft are arranged in the gear box through worm shaft bearings 23, the worm gear shaft is fixedly connected with an output shaft 21 of the stepping motor (the worm gear shaft and the output shaft of the stepping motor can adopt 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 stepping motor 25 rotates according to a certain stepping angle, so that the worm shaft rotates by the same angle, and further drives the turbine gear 25 fixed with the blade, thereby realizing the controllability of the blade inclination angle alpha of the blade. The connecting plate 4 is provided with a wind speed sensor, a temperature sensor 5, a fan connecting positioning hole 6 and a wiring harness fixing clamp 7.

The stepping motor 25 can adopt a two-phase or multi-phase stepping motor, and due to the transmission design of a worm gear and a worm gear, the required holding torque range of the stepping motor is lower and ranges from 0.24Nm to 5Nm, the clamping torque is greater than 0.24Nm, the single-step stepping angle range is 0.75-2 degrees, the motor is convenient to install, the size of the motor is within the range of 50 x 50mm, the applicable voltage range is 5-48V, the rated current is less than 2A, and the rated power is less than 15W.

In one embodiment, the number of teeth of the turbine gear 24 ranges from 28 to 80, the outer diameter of the tooth surface is 30 to 100mm, the width of the tooth surface is 10 to 30mm, and the material is cast tin bronze, aluminum iron bronze or cast iron; the worm 22 is made of 40Cr hardened HRC 50-55, the number of worm heads is 1-4, the pressure angle is 20 degrees, the pitch diameter 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 a vehicle VECU, reads sensor data related to a cooling system through a vehicle CAN bus, transmits the sensor data as an input signal to the fan, and calculates the most suitable blade inclination angle of the fan at present through an internal algorithm; then, a stepping motor beside the single blade is driven to drive a worm to be connected, and then a turbine gear starts to rotate; and the turbine gear shaft is connected with the fan blade shaft, so that the blade inclination angle of the fan is changed to realize the functions of variable flow, efficiency and power consumption.

Referring to fig. 4, the control mechanism 3 of the present invention is fixed on the connecting plate 4, and is connected with the wiring harness of the whole vehicle to transmit electric signals in the form of slip rings 34, and does not participate in the rotation of the fan. The control mechanism 3 comprises a fan ECU controller 31, a CAN bus connecting wire harness 32, a PCB for arranging the ECU, a fan ECU output wire 33 for outputting to the execution mechanism and a temperature sensor, wherein the fan ECU controller 31 is matched with the connecting plate 4 through a bearing and is fixed without participating in the rotation motion of the fan; the CAN bus connection harness 32 CAN be used for data interaction between the fan ECU controller 31 and the vehicle ECU, and reading sensor parameters related to the thermal system.

The PCB circuit board for arranging the ECU comprises the following modules: the device comprises an MCU (microprogrammed control Unit) computing unit, a power supply module, a stepping motor driving module, a circuit protection module, a signal acquisition and conversion module, a CAN (controller area network) module and the like. 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 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 power supply module preferably outputs 5V direct current; a step motor driving module for sending phase driving signals to drive the step motors 25 of the fan blade accessories so as to control the blade inclination angles of the fan blades; the circuit protection module integrates protection strategies of the ECU, including but not limited to: step motor locked rotor protection, overcurrent protection, overvoltage protection, high temperature protection and locked rotor protection; the signal acquisition and conversion module can convert signals acquired by the external sensor, such as temperature signals and wind speed signals, into level signals which can be accepted by the MCU chip; the MCU computing unit is internally integrated with core intelligent control strategy logic, and can realize three fan working modes: the fan is from the variable performance mode, and the intelligent accurate control mode of whole car is united to the fan to and the fan is from the dust removal 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 ambient temperature around the fan is collected in real time through a temperature sensor of the control mechanism 3, when the temperature of an engine cabin is detected to be lower than 65 ℃, a 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 volume; when the temperature of the engine cabin is detected to be 65-75 ℃, the inclination angle of the fan blade is controlled to be 15-45 degrees through the fan MCU algorithm. At the moment, the air volume performance of the fan blades is adjusted to be medium power consumption, medium noise and medium air volume; when the temperature of the engine cabin is detected to be higher than 75 ℃, the inclination angle of the fan blade is controlled to be 45-60 degrees. At the moment, the air volume performance of the fan blades is adjusted to high power consumption, high noise and large air volume.

As shown in fig. 6, the fan is combined with the intelligent precise control mode (combined control) of the whole vehicle: the control mechanism is in communication connection with a CAN bus of a whole vehicle ECU, and reads parameters of sensors in a whole vehicle thermal management system in real time, specifically but not limited to engine water inlet temperature, intercooler air inlet pressure, ambient temperature, an air conditioner compressor pressure switch, a retarder switch and an oil cooler switch. The fan flow demand values of all cooling system accessories are respectively calculated through related parameter input and an internal algorithm of a 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 flow demand. The flow rate sensor can detect the current flow rate of the fan, and the current flow rate is converted into a real-time flow value through internal processing of the control mechanism. The real-time flow value is fed back to 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 fan self-dedusting mode occurs at the moment of starting the fan, the control mechanism adjusts the inclination angle alpha of the fan blades to-15 to-60 degrees, so as to realize the air suction and air blowing reversal of the fan, remove the dust attached to the surfaces of the fan blades, and close the dedusting logic function after the fan dedusting mode is maintained for 1-3 min.

The invention discloses a fan MCU controller which is internally provided with three control strategy logics: the method comprises the following steps of (1) 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 of the stepping motor for controlling the phase; the protection module is used for high temperature or MCU failure protection, and after the MCU fails, the PWM signal is output by default to control the stepping motor to be in a default phase position, 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 met. The cabin environment temperature sensor is used for acquiring the cabin temperature when the fan is automatically controlled.

The working principle of the invention is as follows: the control of the blade inclination angle of the fan with the failure of the stepping motor is controlled by signal acquisition of a sensor of a heat management system of the whole vehicle and air volume requirements of lowest power consumption and lowest noise through internal calculation, so that the flow, power consumption, noise and efficiency output by the fan blades are changed. Meanwhile, the inclination angle of the fan blade is controlled in a real-time closed-loop PID mode through the wind speed sensor, and accurate control of the air quantity of the fan is met. Thereby achieving the fan air output under the lowest power consumption and the lowest noise.

The surface of the fan is provided with the wind speed sensor, the wind speed on the surface of the fan blade 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 blades have the capacity of controlling flow with high precision, and power consumption and noise of the fan can be effectively reduced according to the working condition of the whole vehicle. The fan provided by the invention also has a dust removal mode, so that the blade inclination angle of the fan can move in a negative angle, the mutual conversion of blowing and air suction can be realized under the rotation of the fan in the same direction, and dust and impurities attached to the surface of the fan blade can be quickly removed.

The invention skillfully utilizes 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, the rotation of the worm can drive the worm gear to carry out angle positioning, and the worm gear is fixed with the connecting shaft of the fan blades, so that the blade inclination angle of the plastic blades 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 one-way torque transmission structure of the worm gear and the worm, so that the large torque cannot influence the movement of the stepping motor, the influence of the torque on the accurate control of the inclination angle of the fan blade is eliminated, and the accurate 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 fan blade is 750 mm. The power point speed of the fuel engine is 1900rpm, and the speed ratio of the fan is 1.38. The fan speed is 1900 × 1.38 ═ 2622 rpm; the power of the fan driven by the traditional injection molding fan blades at 2622rpm is at least 35 Kw. As shown in the attached drawing, when the load of the whole vehicle thermal system is low, the air volume is reduced by 20% through the calculation of the fan ECU, and the inclination angle of the fan blade is changed, so that the power consumption of the fan is reduced to 20Kw under the working condition, and the power consumption saving of 17Kw under the working condition is realized. Meanwhile, the noise is also reduced from 115db to 109db, and the noise level is reduced by 6 db. The saved fan power consumption of the fuel engine and the reduced fan noise.

The foregoing shows and describes the general principles and principal structural features of the present invention. The present invention is not limited to the above examples, and various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the claimed invention. 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, characterized in that: the blade-mounted motor is characterized by further comprising a transmission mechanism and a control mechanism, wherein the transmission mechanism comprises a worm wheel and a worm which is in meshing transmission with the worm wheel, the worm wheel is fixedly connected with the blades, the worm is connected with an output shaft of the motor, and the motor is electrically connected with the control mechanism; the motor drives the worm to rotate, and under the effect of the transmission fit of the worm and gear, the blade is driven to rotate, and the blade inclination angle of the blade is changed within the range of 0-360 degrees.

2. The autonomous variable fan of claim 1, wherein: when the temperature of the engine cabin 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 at the moment, the fan blade runs at low power consumption, low noise and low air volume.

3. The autonomous variable fan of claim 1, wherein: when the temperature of the engine cabin 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 at the moment, the air volume performance of the fan blade is adjusted to be medium power consumption, medium noise and medium air volume.

4. The autonomous variable fan of claim 1, wherein: when the temperature of the engine cabin is detected to be higher 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 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.

5. The autonomous variable fan of claim 1, wherein: the control mechanism is in communication connection with a CAN bus of a whole vehicle ECU (electronic control Unit), the parameters of each sensor in the whole vehicle thermal management system are read in real time, the fan flow required values of all cooling system accessories are respectively calculated through related parameter input and an internal algorithm of the control mechanism, the maximum required 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 (pulse-width modulation) phase signal so as to meet the air flow requirement; the flow velocity sensor detects the current flow velocity of the fan, and the current flow velocity is converted into a real-time flow value through internal processing of the control mechanism; the real-time flow value is fed back to the control mechanism as a feedback value, and the control mechanism achieves closed-loop control of the blade inclination angle through comparing the required flow with the flow feedback value and through PID control.

6. The autonomous variable fan of claim 1, wherein: 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.

7. The autonomous variable fan of claim 1, wherein: the motor adopts a stepping motor, the torque is kept to be 0.24-5 Nm, the clamping torque is greater than 0.24Nm, and the single-step stepping angle range is 0.75-2 degrees.

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