eighth generation of Beijing Hyundai Sonata sedan mdash; mdash; Sonata YF, was on the end of the 2010 Guangzhou Motor Show debut.
by the car Hyundai Motor America R & D Center R & D, the appearance ldquo; fluid sculpture rdquo; design and application of cutting-edge smart technology, its target consumer groups locked to the urban elite groups. Produced by the Beijing Hyundai Sonata YF combines the advantages of the US version and Korean version of the Sonata, and the upgrade process in the use of high-tech, equipment levels. Vehicle equipped with a new theta; # 8211; Ⅱ aluminum engine with continuously variable valve timing dual technology (dual CVVT), and with a full 6-speed electronically controlled automatic transmission. 4 also uses a planetary gear differential and closed active wheel speed sensors and other new technologies. 2.0 models maximum power of 121 kW, maximum torque 197 Nmiddot; m; 2.4 models maximum power of 128 kW, maximum torque 227 Nmiddot; m. Here we briefly introduce the technical highlights of the car.
1.theta; # 8211; Ⅱ engine
The engine pure aluminum alloy cylinder, the sealing piston is greatly improved, Furthermore, since the application of technology dual continuously variable valve timing, making the power and fuel economy of the engine are greatly enhanced.
(1) bis continuously variable valve timing system
of the engine to drive the intake camshaft and the exhaust camshaft lubricating system by oil pressure control unit according to an instruction of the engine and the timing sprocket relative rotation, to change the phase of the valve, for dual continuously variable valve timing function.
electrically controlled hydraulic valve has two cavities, the engine control unit controls the amount of movement of the push rod chamber by varying the pressure in the two cavities, the ram drive cam shaft to the sprocket (figure 1). Phase relationship sprocket is fixed, so that rotation of the camshaft, so that the camshaft relative to the crankshaft to produce a lead or lag phase (FIG. 4). Dual continuously variable valve timing system according to engine speed and load optimization intake and exhaust valve opening / closing time, in order to obtain optimum engine performance. When the hairWhen operated at low speed motivation high load conditions, due to the slow speed of the piston movement, the throttle opening degree, the air velocity is low.
FIG. 1 may be a continuously variable valve timing system works
FIG. phase change of the camshaft 4
At this time the engine control unit in advance the phase of intake valve, exhaust valve phase lag. The intake valve with respect to the piston so that early opening, early closing, so that the intake air flow into the cylinder with a sufficient time, the intake air can be prevented reflux. Suitably hysteresis exhaust valve, the exhaust pressure can be relatively increased, thereby increasing the flow rate of the exhaust gas stream, and take advantage of the inertia of the gas flow, the exhaust gas is more completely (FIG. 5).
When the engine is operating at low speed, high load or low-load mode, due to the higher air velocity, so the intake and exhaust valves may be opened and closed completely synchronized with the movement of the piston, intake and exhaust valves and the non-overlapping region . At this phase shift the intake and exhaust camshafts are 0, i.e., completely determined by the timing chain when they are positive. When the engine is operating at partial load, due to the higher air flow velocity, it is possible to delay the phase of the intake valve, to take advantage of the inertia of the intake airflow to be inflated, thereby reducing pumping loss of the engine, and reduces the HC emission. Will also phase delayed exhaust valve, may be utilized so that intake air mixed with the exhaust gas, to achieve internal exhaust gas recirculation within the combustion chamber to reduce nitrogen oxide emissions.
FIG. 5 continuously variable valve timing system of the working process
(2) the fuel evaporative control system
The fuel tank system a pressure sensor mounted (FTPS), and the vent valve mounting (CCV) on the canister, so that both achieve a purification of the air, but also to ensure the security of the fuel system (FIG. 6). Control system by the pressure sensor, one can prevent the fuel tank pressure is too high, on the other hand can detect leakage of the fuel tank, the presence of even small leaks can be detected (FIG. 7).
FIG. 6 fuel tank evaporation control system
FIG. 7 of the fuel tank leak detection
(3) intake
[123 ]
the response depends on the power of the engine charging efficiency, and therefore try to improve charging efficiency, an effective means to improve the power performance of the engine. In engine operation, the intake valve is opened and closed according to a certain frequency, which will form a stream of intake air pulsation frequency. If viewed as a whole inlet chamber, then the chamber must have its resonant frequency unique. When the intake airflow certain harmonic resonance frequency equal to the frequency of the standing wave is formed in the intake passage, then it will not be part of the airflow into the cylinder, thus reducing air intake efficiency. For the removal of the standing wave phenomenon, to improve intake efficiency of the engine under various conditions of the engine which uses a variable inlet.
(4) The exhaust system
Since the exhaust noise of the engine is mainly in the bass frequencies, so the volume of the muffler chamber determines the amount of attenuation of the bass band. The engine of the vehicle body in a case where conditions permit, the volume of the silencer from the
23 L increased 25 L , which makes the exhaust noise is reduced at least 4 dB.
(5) cam slot
to reduce the mass of the camshaft, a side surface of the cam slot treatment done.
(6) needle-type timing chain
The timing chain is rotated each section are made of a needle bearing structure, the sprocket tooth and also to make the corresponding design, which can better resist soot.
2. The transmission
6-speed automatic vehicle transmission, model A6MF2. The transmission torque converter paragraph was slim design, using a differential planet gear 4, more compact. Overall, smaller subsection of the transmission, the quality
light, more agile and smooth shifting.
① hydraulic control valve
The hydraulic control valve controls the operation of each actuator of the transmission (FIG. 8) by the linear solenoid valves 6 and two solenoid valves switch. workBy hydraulic pressure reducing valve as 2 (FIG. 9) is formed of a lower hydraulic pressure, the hydraulic pressure source 6 provides linear solenoid valve and linear solenoid valve and control the respective relay valve achieve a variety of control functions. Following are the power hydraulic valve to the manual valve when the manual valve is closed so that all the actuator elements are in relief. Since all of the relay valve is controlled by a linear solenoid valve, therefore, the process of establishing a hydraulic transmission actuator is controlled according to a program, which makes the high shift transmission quality.
FIG. 8 of the hydraulic control valve
composed of
of the transmission of FIG. 9
② converter
the transmission torque converter ultra-thin, reducing the capacity of the oil in the torque converter, torque converter inertia is reduced, so that the overall transmission table
now more perfect. To improve the air-fuel ratio of the engine, stable power transmission, the torque converter lock-off
sliding clutch lock-up control mode (FIG. 10), in the engine low load region, the torque converter lockup clutch viscous liquid to deliver power transmission mode
FIG converter lock-up control 10
③ automatic transmission fluid to enhance the performance of the engine and the friction durability of an automatic transmission internal friction elements, Hyundai motor company developed a low viscosity high torque automatic transmission fluid SP-Ⅳ. The oil can be improved friction durability of the friction element 2 times, even under severe conditions of use, the replacement cycle of transmission fluid may reach 100,000 km.
Differential ④
In order to realize miniaturization and high torque, the differential differential gear device application (FIG. 11) of the pinions 4, for the same the differential ratio, the transmission torque can be increased by 50 percentage. In addition, the differential also be made sealed, in the case where the drive shaft is not installed, the oil does not leak. To strengthen the lubricating differential, using a wide spacer, increased lubricating oil flow space.
FIG planetary gear differential 114
3. The vehicle stability control (ESC)
① hill start assist control ( HAC)
when the vehicle is started on a slope steeper than 8 percent, in order to prevent the decline in the slope when starting the vehicle along the slope, the vehicle stability control system will automatically perform a time of 2 s vehicle brake ( Figure 12).
FIG hill start assist control 12
② driving wheel speed sensor
In the Hall sensor device added to the permanent magnet (FIG. 13), so that a gap sensor signal is no longer sensitive wheel
sense to solve the defect sensor sensitivity decline after iron contamination. Further this way, also increases the noise immunity of the sensor. ③ acceleration sensor
FIG 13 the driving wheel speed sensor
together with the vehicle body acceleration sensor (FIG. 14), both measuring longitudinal acceleration of the vehicle, but also measure yaw rate of the vehicle body. Vehicle stability control system using these signals, the vehicle can travel more secure and stable.
FIG 14 an acceleration sensor
4. The smart junction box
is not a simple smart junction box fuse / relay junction box, it It is actually an intelligent control unit. It not only can control
in the data transmission system is a local area network, and can directly receive the control switch status signals, and control operation of various electrical appliances.
① input switch detection control
The smart junction box switch detector (FIG. 15) to its OFF state of the transmission central processor, converts it into data, and then transmitted via the bus body control unit, then the control unit receives an instruction from the back of the vehicle body. ② with electrical control
FIG. 15 switch state detector
The detected start and smart junction box receiving the instruction body control unit, then converted into a power control signal to control the respective power control unit and to provide electrical energy (FIG. 16) with the electrical work required by the power control unit. Relay control
FIG 16 an acceleration sensor
③
Smart junction box receiving the instruction of the vehicle body control unit It is then converted into a control signal to control the relay operation of the relay, and then to control the various electrical appliances work (FIG. 17) of a relay.
Sleep Function
FIG. 17 switch state detector
④
If the smart junction box does not receive any data or switch within 5 s, it automatically enters a sleep mode to save power. When the switch state or receive any data, the smart junction box is immediately awakened, into normal operation.
(Liu Zhonglong)