The new Lexus LS460, launched recently in Japan, features new advanced products developed by DENSO Corporation in the areas of the environment, safety, comfort and convenience. They are:
* World’s first motor-driven electric variable valve timing control system;
* New pre-crash safety system components;
* New air conditioning system that provides individually customized air conditioning to each passenger seat;
* World’s thinnest card key for smart entry and start system;
* Instrument cluster with thin film transistor (TFT) display;
* World’s first remote security system with remote immobilizer function, and
* World’s first inertia sensor with inclination-detecting function.
“DENSO’s goal is to develop new technologies to meet customer’s needs and achieve an advanced automotive society where people, cars and the environment co-exist in harmony,” said Oyuki Ogawa, executive vice president, Engineering Research & Development Center and Thermal Systems Business Group.
Motor-Driven Electric Variable Valve Timing Control System
In the area of the environment, vehicles today need to achieve excellent driving performance with better fuel economy and at the same time reduce harmful emission substances. To comply with these requirements, DENSO has developed with Toyota Motor Corporation the world’s first motor-driven variable valve timing control system.
Variable valve timing control systems control the opening/closing timing of intake and exhaust valves for combustion chambers in accordance with driving conditions. DENSO’s newly developed electric variable valve timing control system uses a motor to directly adjust the opening/closing timing of intake valves, a procedure conventionally controlled hydraulically. So, this new system can control intake valve timing more precisely, enabling higher engine output and less fuel consumption. Further, even under difficult operating conditions for conventional systems such as low engine temperature or low engine revolution, the new system precisely controls the valve timing, reducing hydrocarbon in emissions.
New Pre-Crash Safety (PCS) System Components
In the area of safety, DENSO has developed the following four components for Toyota’s new PCS system installed on the Lexus LS460 in Japan and Europe:
* Stereo Image-Processing Electronic Control Unit (ECU) — Developed with Toyota and NEC Electric Corporation, this ECU rapidly processes image signals received from a stereo camera that photographs obstacles appearing in front of the vehicle.
* Driving Assistance ECU (1) — This ECU, developed with Toyota, controls all operations of the PCS system, based on information from the stereo image- processing ECU, and from the front and rear millimeter-wave radar. This ECU also controls the radar cruise control system at all speeds and the lane- keeping assist system.
* Front Millimeter-Wave Radar — Detects obstacles that appear in front of the vehicle and relays that information to the driving assistance ECU. For the new PCS system, DENSO has improved the radar’s detecting capability for close distances by also revising the millimeter-wave modulation method for the front millimeter-wave radar.
* Pre-Crash Seatbelt ECU — A smaller and lighter pre-crash seatbelt ECU, developed by DENSO, controls seatbelt retraction based on signals from the driving assistance ECU. The new pre-crash seatbelt ECU is approximately one- third the volume and less than half the weight of a conventional pre-crash seatbelt ECU.
New Air Conditioning System
In the area of comfort, DENSO has developed a new air conditioning system that can provide more comfortably conditioned air to passengers seated not only in front seats, but also in rear seats. Four components were newly developed for this system: the world’s first matrix infrared ray (IR) sensor (2) that detects the surface temperature distribution inside the vehicle cabin; the heating, ventilating and air-conditioning (HVAC) unit for the front air conditioner; the cooling unit for the rear air conditioner, and an oxygen concentration conditioner.
Features of the new air conditioning system include:
* Temperatures that can be separately controlled for each passenger seat;
* Temperatures and airflow quantity for passengers seated in rear seats that can be automatically controlled by using the matrix IR sensor to detect passenger surface temperature changes;
* More efficient and quieter system operations due to the new HVAC unit that utilizes a highly efficient evaporator, heater and motor, and a newly developed film door with a unique structure. The new film door also allows separate control of airflow quantities to driver and passenger sides, and an approximate 20 percent size reduction in volume of the HVAC unit compared to a conventional unit;
* Quieter rear-seat environment resulting from a newly developed duct structure for intake ports in the cooling unit;
* Prevention of a decrease in cabin oxygen concentration due to the oxygen concentration conditioner that supplies air with an increased concentration of oxygen.
Card Key for Smart Entry and Start System
In the area of convenience, DENSO has developed a new card key, the world’s thinnest, for DENSO’s smart entry and start system. DENSO achieved this world’s first by insert-molding the circuit board with resin, resulting in a thickness of only 3.35 millimeters. This card key also features the world’s highest-level bending strength, and the world’s first totally waterproof circuit part. As a result, the card key can be easily stored in a wallet or card case, and maintains high resistance to bending, breaking and water.
Instrument Cluster with TFT Display
DENSO’s new instrument cluster with the TFT display provides a variety of information for easy driver recognition as well as improved environmental features. For the TFT display, DENSO developed a new backlight unit using a high-luminance, light-emitting diode (LED). It is the first in the world to use the LED for an instrument cluster’s TFT display. Compared to a conventional backlight unit, which uses cold cathode fluorescent lamps, the newly developed backlight unit does not contain mercury, an environmentally hazardous substance, and reduces power consumption by approximately 20 percent, contributing to less fuel consumption.
Remote Security System with Remote Immobilizer Function
DENSO has developed together with Toyota the world’s first remote security system with a remote immobilizer function that coordinates with Lexus’s telematics service, “G-Link.” If the vehicle and car key with an immobilizer function(3) are stolen, the support center sends orders to the vehicle to prohibit the engine’s restart after it stops. For safety purposes, the orders from the information center do not take effect until the vehicle is completely parked. Another new function for this remote security system is the remote control of the vehicle’s door locks, hazard lamps, and power windows that use the driver’s cellular phone. This system will be installed on the Lexus LS460 sold in Japan.
Inertia Sensor with Inclination-Detecting Function
The newly developed inertia sensor is the first in the world to combine an inertia sensor for vehicle stability control (VSC)(4) and an inclination sensor for detecting a vehicle’s theft. The VSC inertia sensor detects acceleration and angular velocity to determine the vehicle’s posture when the vehicle is running, and the inclination sensor detects the vehicle’s inclination caused by the vehicle’s theft when the vehicle is parked. DENSO integrated these two sensors into the new inertia sensor, while achieving an approximate 25 percent size reduction in volume compared to the conventional inertia sensor without the inclination-detecting function. The new sensor will be installed on the Lexus LS460 sold mainly in Europe.