Thursday 17 October 2013

Types Of Belt Conveyor Drives | Belt Conveyor Drive Arrangement

Types and Selection of Drives:
  • Single Unsnubbed Bare / Lagged pulley Drive
  • Snubbed Bare / Lagged Pulley Drive
  • Tandem Drive
  • Special Drives
Single Unsnubbed Bare / Lagged Pulley Drive:
This is the simplest drive arrangement consisting of a steel pulley connected to a motor and the belt wrapped round it on an arc of 180°. This can be used for low capacity short center conveyors handling non-abrasive material. The pulley may be lagged to increase the coefficient of friction.
01-unsnubbed bare pulley-lagging-snub pulley-belt conveyor drive arrangement-driving pulley-tandem drive

Snubbed Bare / Lagged Pulley Drive:
Here the angle of wrap is increased from 180° to 210° or even up to 230°, by providing a snub pulley to the driving pulley. In majority of medium to large capacity belt conveyors, handling mild abrasive to fairly abrasive materials, 210° snub pulley drive with load pulley lagged with hard rubber is adopted.
01-snubbed bare pulley drive-snubbed lagged drive pulley-large capacity belt conveyors-snub pulley-driving pulley


Tandem drive:
Here belt tension estimated to be high; the angle of wrap is increased by adopting tandem drives. Both of tandem pulleys are driven. The tandem drive with arc of contact from 300° to 480° or more can operate with one or two motors. The location of such drive is usually determined by the physical requirements of the plant and structural constraints.
01-tandem drive-two pulley drives-belt conveyor angle of wrap-types of belt conveyor drives-belt conveyor drive arrangement

Special Drive:
Special drives with snub pulleys and pressure belts used in heavy and long conveyors.
01-pressure belts-special belt conveyor drives-tandem drive-driving pulley-special drive with pressure belt

Pulley | Belt Conveyor Pulley | Belt Conveyor Pulley Types | Belt Conveyor Power Calculation

Pulley:
01-standard pulley-spun end curve crown pulley-steel pulley-straight faced pulley-pulley mechanism-pulley ratio-pulley size-pulley selection
The diameters of standard pulleys are: 200, 250, 315, 400, 500, 630, 800, 1000, 1250, 1400 and 1600 mm. pulley may be straight faced or crowned. The crown serves to keep the belt centered. The height of the crown is usually 0.5% of the pulley width, but not less than 4 mm. The pulley diameter Dp depends on the number of plies of belt and may be also be determined from the formula:
Dp > K.i (mm)
Where
K = a factor depending on the number of plies (125 to 150)
i = no of plies
The compound value should be rounded off to the nearest standard size. While selecting the pulley diameter it should be ascertained that the diameter selected is larger than the minimum diameter of pulley for the particular belt selected.
The drive pulley may be lagged by rubber coating whenever necessary, to increase the coefficient of friction. The lagging thickness shall vary between 6 to 12 mm. The hardness of rubber lagging of the pulley shall be less than that of the cover rubber of the running belt.
Pulley types:
Pulleys are manufactured in a wide range of sizes, consisting of a continuous rim and two end discs fitted with hubs. In most of the conveyor pulleys intermediate stiffening discs are welded inside the rim. Other pulleys are self cleaning wing types which are used as the tail, take-up, or snub pulley where material tends to build up on the pulley face. Magnetic types of pulleys are used to remove tramp iron from the material being conveyed.
Typical welded steel pulley-Drum conveyor pulley
01-typical welded steel pulley-pulley types-pulley design-pulley system-pulley problems-pulley size
Spun end curve crown pulley
01-conveyor pulleys-spun end crown pulley-self cleaning wing pulley-snub pulley-pulley face-magenetic pulley
Spiral drum conveyor pulley
01-spiral drum conveyor pulley-pulley types-pulley with ball bearings-pulley for handling bulk load
Welded steel pulley with diamond grooved lagging
01-types of pulley-welded steel pulley-grooved lagging-belt conveyor drive-belt conveyor resistance-belt wrapping over pulleys
Welded steel pulley with grooved Lagging
01-welded steel pulley with grooved lagging-pulley types-belt conveyor speed reduction mechanism-belt conveyor drive arrangement
Spiral Wing Conveyor pulley
01-spiral wing conveyor pulley-belt conveyor calculation-belt conveyor formula-belt conveyor gallery

Power calculation for the drive unit:
The horse power required at the drive of a belt conveyor is derived from the following formula:
H.P = Te . V
Where
Te is the effective tension in the belt in N
V = velocity of the belt in m/s
The required effective tension Te on the driving pulley of a belt conveyor is obtained by adding up all the resistances.

CONVEYOR TAKE UP ARRANGEMENT

Conveyor Take-up Arrangement:
01-belt conveyor-take up arrangement-screw take up-take up pulley-automatic take up device-fixed take up device-manual take up-self adjusting take up devices
All belt conveyors require the use of some form of take-up device for the following reasons:
  • To ensure adequate tension of the belt leaving the drive pulley so as to avoid any slippage of the belt
  • To ensure proper belt tension at the loading and other points along the conveyor
  • To compensate for changes in belt length due to elongation
  • To provide extra length of belt when necessary for splicing purpose.
  • Usually there are two types of take up arrangements.
    • Fixed take up device that may be adjusted periodically by manual operation
    • Automatic take up devices for constant load type
    In a screw take up system the take up pulley rotates in two bearing blocks which may slide on stationery guide ways with the help of two screws. The tension is created by the two screws which are tightened and periodically adjusted with a spanner. It is preferable to use screws with trapezoidal thread t decrease the effort required to tighten the belt.
    01-hydraulic take up device-pneumatic take up device-electrical take up device-self adjusting take up device-automatic take up device
    The main problem with the use of manual take-up is that it requires a vigilant and careful operator to observe when take up adjustment is required. Perfect tension adjustment with this system is also not possible. For this reason these devices are used only in case of short conveyors of up 60 m length and light duty.
    In automatic take up arrangement the take up pulley is mounted on slides or on a trolley which is pulled backwards by means of a steel rope and deflecting pulleys. The carriage travels on guide ways mounted parallel to the longitudinal axis of the conveyor, i.e., horizontally in horizontal conveyors and at an incline in inclined conveyors. Hydraulic, pneumatic and electrical take up devices are also used.
    Automatic take-up has the following features:
    • It is self adjusting and automatic
    • Greater take-up movement is possible.

Belt Conveyor Take Up Design | Conveyor Belt Take Up System | Horizontal Take Up In Belt Conveyor

Belt Conveyors for bulk materials:
Take up Arrangement:
All belt conveyors require the use of some form of take up device for the following reasons:
1. To ensure adequate tension of the belt leaving the drive pulley so us to avoid any slippage of the belt.
2. To ensure proper belt tension at the loading and other points along the conveyor.
3. To compensate for changes in belt length due to elongation.
4. To provide extra length of belt when necessary for splicing purpose.
01-belt-conveyor - belt conveyor for bulk materials
Usually there are two types of take up arrangements.
These are:
1. Fixed take up device that may be adjusted periodically by manual operation
2. Automatic take up device (constant load type)

Manual Screw Take Up:
The most commonly used manual take up is the screw take up. In a screw take up system the take up pulley rotates in two bearing blocks which may slide on stationery guide ways with the help of two screws. The tension is created by the two screws which are tightened and periodically adjusted with a spanner. It is preferable to use screws with trapezoidal thread to decrease the effort required to tighten the belt.
01-flat belt conveyor - gravity conveyor - rubber belt conveyor
The main problem with the use of manual take up is that it requires a vigilant and careful operator to observe when take up adjustment is required. Perfect tension adjustment with this system is also not possible. For these reason these devices are used only in case of short conveyors of up 60m length and light duty.

Automatic Take Up:
In automatic take up arrangement the take up pulley is mounted on slides or on a trolley which is pulled backwards by means of a steel rope and deflecting pulleys. The carriage travels on guide ways mounted parallel to the longitudinal axis of the conveyor, i.e., horizontally in horizontal conveyors (Ex.: Gravity type automatic take up arrangement) and at an incline in inclined conveyors. Hydraulic, Pneumatic and electrical take up devices are also used.
01-horizontal take up in belt conveyor -  conveyor belt loop take up
Automatic take up has the following features:
1. It is self adjusting and automatic
2. Greater take up movement is possible
01-steel belt conveyors -  material handling conveyors -  roller conveyor
For the perfect conveying of materials, adding a resistance with the peripheral forces on the driving pulley of a belt conveyor is important. Some of the resistances are:
1. The inertial and frictional resistance due to acceleration of the material at the loading area
2. Resistance due to friction on the side walls of the skirt board at the loading area.
3. Pulley bearing resistance applicable for other than the driving pulley
4. Resistance due to the wrapping of the belt on pulleys
5. Special resistances include
a. Resistance due to idler tilting
b. Resistance due to friction between material and skirt plate
c. Frictional resistance due to belt cleaners
d. Resistance due to friction at the discharge plough
Special resistances are usually small. Here the resistance due to idler tilting and skirt resistance is ignored. There being no discharge plough the resistance due to plough is ignored. For belt speeds greater than 3 m/s, the edge clearances are applicable.

Wednesday 2 October 2013

Idling Stop Technology | i-stop

Idle stop systems save fuel by shutting down a vehicle’s engine automatically when the car is stationary and restarting it when the driver resumes driving. Especially in urban areas, drivers often let their car’s engine idle at traffic lights or when stopped in traffic jams. Switching off the engine to stop it idling in these situations enhances fuel economy by about 10% under Japan’s 10-15 mode tests.
Conventional idling stop systems restart a vehicle’s engine with an electric motor using exactly the same process as when the engine is started normally. Mazda’s ”i-stop”, on the other hand, restarts the engine through combustion. Mazda’s system initiates engine restart by injecting fuel directly into a cylinder while the engine is stopped, and igniting it to generate downward piston force. This system not only saves fuel, but also restarts the engine more quickly and quietly than a conventional idle-stop system.
    01-i-stop operation-operating principle of the i-stop-idling stop technology-piston position control
  • Piston stop position control and combustion restart technology
    •  
    In order to restart the engine by combustion, it’s vital for the compression-stroke pistons and expansion-stroke pistons to be stopped at exactly the correct positions to create the right balance of air volumes. Consequently, Mazda’s ”i-stop” effects precise control over the piston positions during engine shutdown. With all the pistons stopped in their optimum position, the system restarts the engine by identifying the initial cylinder to fire, injecting fuel into it, and then igniting it. Even at extremely low rpm, cylinders are continuously selected for ignition, and the engine quickly picks up to idle speed.
    Thanks to these technologies, the engine will restart with exactly the same timing every time and will return to idle speed in just 0.35 seconds, roughly half the time of a conventional electric motor idling stop system. As a result, drivers will feel no delay when resuming their drive. With the ”i-stop”, Mazda can offer a comfortable and stress-free ride as well as better fuel economy.

    Direct Injection Gasoline Engine | DISI Engine

    02-direct-injection-engine-disi engine-gasoline engine
    In developing the DISI engine, we aimed to cool the interior of the cylinder as much as possible by promoting fuel vaporization and uniform mixing of atomized fuel and air. This produces a high charging efficiency of the air-fuel mixture and a high compression ratio, which results in significant improvements in both torque and fuel efficiency.
    Characteristics of the direct injection engine:
  • Fuel is injected from a tiny nozzle into a relatively large cylinder, so it has a high latent heat of vaporization, which efficiently cools the air within (in-cylinder cooling effect).
  • The air temperature in the cylinder decreases, which means:
    • (1) more air may be charged into the combustion chamber, which produces increased torque.
    • (2) the engine is less prone to knocking. This contributes to increased torque, and enables a higher compression ratio that also contributes to good fuel efficiency.
    In a direct injection engine, however, the fuel skips the waiting period it would have to endure inside a standard engine and instead proceeds straight to the combustion chamber. This allows the fuel to burn more evenly and thoroughly. For the driver, that can translate to better mileage and greater power to the wheels.
    In the past, direct injection posed too many technical hurdles to make it worthwhile for mass market gasoline automobiles. But with advances in technology and greater pressure to make cars run more cleanly and efficiently, it looks as if gasoline direct injection — or GDI as it’s referred to in industry lingo — is here to stay. In fact, most of the major car manufacturers make or plan to soon introduce gasoline cars that take advantage of this fuel saving and performance enhancing system. 
  • Miller Cycle | Sequential Valve Timing (S-VT) | Continuously Variable Transmission (CVT)

    The key to improving fuel efficiency lies in raising an engine’s thermal efficiency. This can be done by increasing the expansion ratio. The expansion ratio is the amount of work the engine does each time the air-fuel mixture in the cylinders detonates. However, in conventional engines the expansion ratio is the same as the compression ratio, so increasing the expansion ratio will also raise the compression ratio. This is a problem because a high compression ratio causes abnormal combustion, or knocking.
    01-compression ratio-expansion ratio-miller cycle engine
    The answer is the Miller-cycle engine. By delaying the closure of the intake valves, compression actually begins part way through the compression stroke, which results in a reduced compression ratio. At the same time, changing the shape of the piston crown decreases the combustion chamber minimum volume, resulting in a larger expansion ratio. In this way we can decrease the compression ratio and while increasing the expansion ratio. In other words, the Miller-cycle engine has a higher expansion ratio than compression ratio.
    02-MZR engine-Miller Cycle Engine-Higher expansion ratio
    Mazda’s naturally-aspirated MZR 1.3L Miller-cycle engine delays the closure of the intake valves to improve the thermal efficiency (high expansion ratio). Sequential-valve timing (S-VT) is also employed to optimize intake valve timing and ensure sufficient torque for cruising and accelerating. Furthermore, the engine is mated to a continuously variable transmission (CVT) for a perfect blend of responsive acceleration, smooth gear shifts and top-class fuel economy.

    Catalyst Technology | Single Nano-Catalyst | Precious Metal Dispersion Model

    In automobile catalytic converters, the surface conditions of the precious metals—the catalyst materials—have a large effect on their ability to clean emissions. Conventionally, precious metal particles are adhered to a base material. However, heat from the exhaust gas causes the particles to collect together and agglomerate to form larger particles. This reduces the surface area of the precious metals and deteriorates their performance as catalysts. To counter this effect, large amounts of precious metals must be used in conventional catalytic converters. As an alternative, Mazda takes advantage of single nanotechnology to realize a unique and new catalyst structure in which precious metal particles are individually embedded into the base material.
    01-catalyst_technology-precious metal dispersion model
    The new catalyst has two main features.
    1. It inhibits the thermal deterioration caused by the agglomeration of precious metal particles
    2. It offers a significant improvement in oxygen absorption and release rates for enhanced emissions cleaning
    With these features, the amount of precious metals needed to ensure the same level of effectiveness is reduced by 70 to 90 percent compared to previous products. At the same time, the performance of the catalytic converter is almost unaffected by harsh driving styles.
    01-catalyst_technology-oxygen absorption rate-oxygen absorption volume-nano particles technology
    This technology can significantly reduce the amounts of expensive precious metals such as platinum, palladium and rhodium needed for three-way catalysts to effectively clean exhaust emissions from gasoline engines.

    Next-Generation ‘SKYACTIV’ Technologies |

    01-2012-Mazda3-Skyactiv-Image-PETROL ENGINE-AUTOMATIC TRANSMISSION
    Highlights of the SKYACTIV technologies:
    • SKYACTIV-G: a next-generation highly-efficient direct-injection gasoline engine with the world’s highest compression ratio of 14.0:1
    • SKYACTIV-D: a next-generation clean diesel engine with the world’s lowest compression ratio of 14.0:1
    • SKYACTIV-Drive: a next-generation highly-efficient automatic transmission
    • A next-generation manual transmission with a light shift feel, compact size and significantly reduced weight
    • A next-generation lightweight, highly-rigid body with outstanding crash safety performance
    • A next-generation high-performance lightweight chassis that balances precise handling with a comfortable ride
     
    - First product to be equipped with SKYACTIV technology will be a Mazda Demio featuring an improved, fuel-efficient, next-generation direct-injection engine that achieves fuel economy of 30 km/L.
    01-inline-skyactiv-technologies-chASSIS DESIGN-BODY DESIGN-DRIVE DESIGN-DIRECT INJECTION GASOLINE ENGINE
    Overview of the SKYACTIV technologies
    1. SKYACTIV-G
    A next-generation highly-efficient direct-injection gasoline engine that achieves the world’s highest gasoline engine compression ratio of 14.0:1 with no abnormal combustion (knocking)
    • The world’s first gasoline engine for mass production vehicles to achieve a high compression ratio of 14.0:1
    • Significantly improved engine efficiency thanks to the high compression combustion, resulting in 15 percent increases in fuel efficiency and torque
    • Improved everyday driving thanks to increased torque at low- to mid-engine speeds
    • A 4-2-1 exhaust system, cavity pistons, multi hole injectors and other innovations enable the high compression ratio
    2. SKYACTIV-D
    A next-generation clean diesel engine that will meet global emissions regulations without expensive NOx after treatments — urea selective catalytic reduction (SCR) or a Lean NOx Trap (LNT) — thanks to the world’s lowest diesel engine compression ratio of 14.0:1
    • 20 percent better fuel efficiency thanks to the low compression ratio of 14.0:1
    • A new two-stage turbocharger realizes smooth and linear response from low to high engine speeds, and greatly increases low- and high-end torque (up to the 5,200 rpm rev limit)
    • Complies with global emissions regulations (Euro6 in Europe, Tier2Bin5 in North America, and the Post New Long-Term Regulations in Japan), without expensive NOx after treatment
    3. SKYACTIV-Drive
    A next-generation highly efficient automatic transmission that achieves excellent torque transfer efficiency through a wider lock-up range and features the best attributes of all transmission types
    • Combines all the advantages of conventional automatic transmissions, continuously variable transmissions, and dual clutch transmissions
    • A dramatically widened lock-up range improves torque transfer efficiency and realizes a direct driving feel that is equivalent to a manual transmission
    • A 4-to-7 percent improvement in fuel economy compared to the current transmission
    4. SKYACTIV-MT
    A light and compact next-generation manual transmission with crisp and light shift feel like that of a sports car, optimized for a front-engine front-wheel-drive layout
    • Short stroke and light shift feel
    • Significantly reduced size and weight due to a revised structure
    • More efficient vehicle packaging thanks to its compact size
    • Improved fuel economy due to reduced internal friction
    5. SKYACTIV-Body
    A next-generation lightweight, highly-rigid body with outstanding crash safety performance and high rigidity for greater driving pleasure
    • High rigidity and lightness (8 percent lighter, 30 percent more rigid)
    • Outstanding crash safety performance and lightness
    • A "straight structure" in which each part of the frame is configured to be as straight as possible. Additionally, a "continuous framework" approach was adopted in which each section functions in a coordinated manner with the other connecting sections
    • Reduced weight through optimized bonding methods and expanded use of high-tensile steel
    6. SKYACTIV-Chassis
    A next-generation high-performance lightweight chassis that balances precise handling with a comfortable ride feel to realize driving pleasure
    • Newly developed front strut and rear multilink suspension ensures high rigidity and lightness (The entire chassis is 14 percent lighter than the previous version.)
    • Mid-speed agility and high-speed stability — enhanced ride quality at all speeds achieved through a revision of the functional allocation of all the suspension and steering components

    Weight Reduction Technology | Fuel Economy Factors | Light Weight Technologies | Cutting Edge Technologies

    Weight has a significant effect on a vehicle’s basic ability to go, corner and stop. Furthermore, environmental and economic factors such as fuel economy are also strongly influenced by vehicle weight.
    Mazda strives to minimize the weight of every car it develops. The all-new Mazda2 (Demio) launched in July 2007 is a perfect example. During development, each individual part was examined and any unnecessary material was removed. The finished vehicle is around 100 kilograms lighter than the first generation Mazda2.
    Mazda is committed to continually improve driving dynamics and fuel efficiency by deploying its lightweight technologies and resistance reduction techniques.
    A dedicated team was formed to develop and test weight reduction techniques for the all-new Mazda2 well before actual vehicle development began. The team employed cutting-edge simulation software to analyze various methods. These were then tested against vehicle driving dynamics using prototype models.
    This advanced technology development, conducted for Mazda’s new compact car, resulted in the creation of an impact absorbing concept that uses a new body framework and high tensile steel. Spot welding and weld bonds were also employed to strengthen specific locations that are subjected to greater loads. This has become Mazda’s new approach to weight management.
    • Bonnet
    01-car bonnet design-car body design-car door design
    With a smaller striker assembly and thinner hinges, the bonnet saves 0.69kg.
    • Body Shell
    Smaller dimensions alone would have lowered the weight of the body shell by four kg, to 233 kg. Measures needed to increase rigidity and crash resistance would have then raised it up to 244 kg. But thanks to an optimised body structure, weight was reduced to 215 kg, 22 kg less than the old Mazda 2.
    • Door-Mounted Speakers
    01-car mounted speakers
    Mazda’s weight watchers were also at work with the door-mounted speakers. By changing the magnets from a ferrite type to neodymium, and making the plastic moulding single-peace, a total weight savings of 0.98 kg was achieved.
    • Intake and Cooling Systems
    For the intake system, Mazda engineers moved the fresh air inlet from its original position behind the left headlamp to the top of the radiator shroud. This new position removed the need for the resonator and baffle.
    • Suspension
    01-Mazda3_sedan_suspension_front
    01-Mazda3_sedan_suspension_rear
    Mazda weight specialists were able to save a impressive 13 kg using weight optimising measures in the suspension. These included making the trailing arm on the rear axle shorter and giving the front lower arms an open-section structure. This reduction in unsprung weight means both better handling and ride comfort.
    • Exhaust System
    Mazda eliminated the underfoot catalyst, and for the 1.3-litre petrol model, the presilencer used in the Mazda2 until now was also eliminated.
    • Other points
    01-Mazda3_sedan_airbags-chassis design
    The shift lever assembly, base plate thickness and rib configuration for automatic transmission models were optimized. The shift knob itself was also made smaller and its positioning was improved. These changes saved 0.85 kilograms.

    Technology of Hydrogen Fueled Rotary Engine | Dual Fuel System ( Hydrogen + Gasoline)

    This hydrogen engine takes advantage of the characteristics of Mazda’s unique rotary engine and maintains a natural driving feeling unique to internal combustion engines. It also achieves excellent environmental performance with zero CO2 emissions.
    Further, the hydrogen engine ensures performance and reliability equal to that of a gasoline engine. Since the gasoline version requires only a few design changes to allow it to operate on hydrogen, hydrogen-fueled rotary engine vehicles can be realized at low cost. In addition, because the dual-fuel system allows the engine to run on both hydrogen and gasoline, it is highly convenient for long-distance journeys and trips to areas with no hydrogen fuel supply.
    01-renesis hydrogen rotary engine-reference exhibit (RE) technology-electronic controlled gas injection-EGR (Exhaust Gas Recirculation)-Dual Fuel system
    Technology of the RENESIS Hydrogen Rotary Engine:
    The RENESIS hydrogen rotary engine employs direct injection, with electronically-controlled hydrogen gas injectors. This system draws in air from a side port and injects hydrogen directly into the intake chamber with an electronically-controlled hydrogen gas injector installed on the top of the rotor housing. The technology illustrated below takes full advantage of the benefits of the rotary engine in achieving hydrogen combustion.

    01-hYDROGEN FUELED ROTARY ENGINE CONCEPT-DUAL FUEL SYSTEM-WITH ELECTRONICALLY CONTROLLED HYDROGEN GAS INJECTOR

    RE Features suited to Hydrogen Combustion
    In the practical application of hydrogen internal combustion engines, avoidance of so-called backfiring (premature ignition) is a major issue. Backfiring is ignition caused by the fuel coming in contact with hot engine parts during the intake process. In reciprocal engines, the intake, compression, combustion and exhaust processes take place in the same location—within the cylinders. As a result, the ignition plugs and exhaust valves reach a high temperature due to the heat of combustion and the intake process becomes prone to backfiring.
    In contrast, the RE structure has no intake and exhaust valves, and the low-temperature intake chamber and high-temperature combustion chamber are separated. This allows good combustion and helps avoid backfiring.
    Further, the RE encourages thorough mixing of hydrogen and air since the flow of the air-fuel mixture is stronger and the duration of the intake process is longer than in reciprocal engines.
    01-mazda-hydrogen RE technologies-Dual fuel Car-Hydrogen and gasoline-Hydrogen rotary engine
    Combined use of Direct Injection and Premixing
    Aiming to achieve a high output in hydrogen fuel mode, a direct injection system is applied by installing an electronically-controlled hydrogen gas injector on the top of the rotor housing. Structurally, the RE has considerable freedom of injector layout, so it is well suited to direct injection.
    Further, a gas injector for premixing is installed on the intake pipe enabling the combined use of direct injection and premixing, depending on driving conditions. This produces optimal hydrogen combustion.
    When in the gasoline fuel mode, fuel is supplied from the same gasoline injector as in the standard gasoline engine.

    Adoption of Lean Burn and EGR
    Lean burn and exhaust gas recirculation (EGR) are adopted to reduce nitrogen oxide (NOx) emissions. NOx is primarily reduced by lean burn at low engine speeds, and by EGR and a three-way catalyst at high engine speeds. The three-way catalyst is the same as the system used with the standard gasoline engine.
    Optimal and appropriate use of lean burn and EGR satisfies both goals of high output and low emissions. The volume of NOx emissions is about 90 percent reduced from the 2005 reference level.
    01-EGR System-Exhaust gas Recirculation-layout
    Dual Fuel System
    When the system runs out of hydrogen fuel, it automatically switches to gasoline fuel. For increased convenience, the driver can also manually shift the fuel from hydrogen to gasoline at the touch of a button.
    01-dual fuel system-custom exhaust systems-RX7fp

    Common Rail Type Fuel Injection System

    01-bosch-common rail injection system-cutting edge diesel technology-ultra high performance 12 cylinder engine
    Electronic control common rail type fuel injection system drives an integrated fuel pump at an ultrahigh pressure to distribute fuel to each injector per cylinder through a common rail.
    01-Bosch_common_rail_injector
    01-common rail fuel injection system
    This enables optimum combustion to generate big horsepower, and reduce PM* (diesel plume) and fuel consumption.
    01-common rail type fuel injection system-distribute in ultrahigh pressure- optimum combustion rate
    Bosch will supply the complete common-rail injection system for the high-performance 12-cylinder engine introduced by Peugeot Sport for its latest racing car. The system comprises high-pressure pumps, a fuel rail shared by all cylinders (i.e. a common rail), piezo in-line injectors, and the central control unit which compiles and processes all relevant sensor data.

    DISI Turbo | Direct Injection Spark Ignition Technology | Variable Timing Technology

    DISI includes a whole new set of innovations for gasoline engines. To mention a few, direct injection (including cooling the air-gasoline mixture), a new combustion chamber geometry, variable timing technology, and nanotechnology for the catalyst. This all makes the engines consume 20 percent less while getting 15 to 20 percent better performance.
    01-DISI Turbo Engine-Direct Injection Spark Ignition system-idle stop mechanism
    Further developments for its diesels: new direct injection technology (most European automakers are switching to piezoelectric injectors), making the engine lighter, DPF, and urea technology to reduce NOx emissions
    01-Direct Injection spark ignition-DISI Turbo Technology-engine-schematic arrangement
    Mazda’s DISI* engines balance sporty driving with outstanding environment performance. With the next generation engine in the series, we are aiming for a 15% ~ 20% improvement in dynamic performance and a 20% increase in fuel economy (compared with a Mazda 2.0L gasoline engine). Based on the direct injection system, we aim to reduce all energy losses (see figure on the right) and improve thermal efficiency through innovative engineering in a variety of technological areas. Among these technologies we are paying particular attention to direct injection, combustion control, variable valve system technology and catalyst technology. Also, among the various fuels on the market, we are studying the use of flex-fuel.

    Biotech Materials | Bio-Plastics | Bio-Fabrics

    Today, various automobile parts are made from plastics, which are reliant on the supply of petroleum. There is a need to find new materials for these parts so we can promote a post-petroleum era and reduce CO2 emissions.
    01-plastic injection moulds-bio plastics-automobile components-light weight materials
    The automobile industry’s first plant-derived bio-plastic, which can be injection-molded to ensure thermal and shock resistance and a beautiful finish.
    High Strength Heat Resistant Heat Materials
    01-high strength-high resistant - high reliability-plastics-roto molding-foam molding-plastic injection molding
    To be suitable for use as automobile parts, plant-derived plastics (bio-plastics) must have the required strength (shock impact resistance) and heat resistance.
    It resulted in the creation of a bio-plastic with the high strength, heat resistance and high quality finish necessary for injection-molded automobile interior parts. It is the first bio-plastic in the automobile industry that maintains a high plant-derived content (over 80 percent). We altered the molecular structure of poly-lactic acid extracted from plants to raise its melting point and developed it as a nucleating agent. A compatibilizer compound*2 was also developed to highly disperse the shock-absorbing flexible ingredients. These two breakthroughs improved material’s ability to uniformly absorb and release energy generated by impacts.\
    This bio-plastic is three times the shock impact resistance along with 25 percent higher heat resistance when compared to contemporary bio-plastics used for items such as electrical appliances.
    And unlike conventional bio-plastics whose properties are suitable for press-forming only, Mazda’s bio-plastic can be extrusion-molded. Consequently, this bio-plastic can be used for various car parts.
    The Premacy Hydrogen RE Hybrid featured this bio-plastic in the vehicle’s instrument panel and other interior fittings.
    01-bio tech materials-the carbon cycle-bioplastic decomposition-Co2 levels-co2 emissions
    Less CO2 Emitted, Less Energy Consumed and less Material Used
    Bio-plastic is a plant-derived and carbon-neutral material. It reduces reliance on fossil fuels and therefore also cuts CO2 emissions. In addition, its manufacture involves fermentation of natural materials such as starches and sugars. As a result, it requires 30 percent less energy to produce than petroleum-base polypropylene plastics. The new bio-plastic is also stronger than other plastics, which means parts can be thinner so less material is required for production.
    Bio-Fabrics:
    01-BIOFRONTfabric fibers-tango biofabrics-bioplastic
    The world’s first bio-fabric made with completely plant-derived fibers, suitable for use in vehicle interiors. This bio-fabric does not contain any oil-based materials, yet it possesses the qualities and durability required for use in vehicle seat covers. Resistant to abrasion and damage from sunlight, in addition to being flame retardant, the new bio-fabric meets the highest quality standards.
    01-honda-biofabric-plant based plastics-automobile fabric
    A new poly-lactic acid —as a crystallization agent to control the entire molecular architecture of raw resins to form a "tereo complex structure*2." The technique was used to improve fiber strength until the fabric attained sufficient resistance to abrasion and light damage for practical use in vehicle seat covers.
    01-mazda-biofabric-biotech materials-seat covers
    The technology enables the production of fibers made from 100 percent plant-derived poly-lactic acid which are well-suited for automobile applications. Other crucial qualities necessary for the highest performing fabrics, such as fire retardant properties

    Hybrid Synergy Drive (HSD) Technology | Hybrid System | Hybrid Cars

    What Is a Hybrid System?

    A hybrid system combines different power sources to maximize each one’s strengths, while compensating for the others’ shortcomings. A gasoline-electric hybrid system, for example, combines an internal combustion engine’s high-speed power with the clean efficiency and low-speed torque of an electric motor that never needs to be plugged in.
    01-hybrid-cars-gasoline electric hybrid system with internal combustion engine

    Are All Hybrids Created Equal?

    There are several ways in which electric motors and a gas/petrol engine can be combined.
    Toyota perfected the series/parallel or "full" hybrid to deliver the energy-saving benefit of a series hybrid together with the acceleration benefit of a parallel hybrid. Two key technologies — the power split device and sophisticated energy management — make this possible. They constantly optimize the flows of mechanical power and electric power for safe and comfortable vehicle operation at the highest possible efficiency.
    01-ecu control-system control-conceptual diagram-HSD work

    The Full Hybrid

    Toyota’s unique hybrid system combines an electric motor and a gasoline engine in the most efficient manner. It saves fuel and reduces emissions while giving ample power.
    Taking advantage of the electric motors’ low-speed torque at start-off
    When the car starts off, Toyota’s hybrid vehicles use only the electric motors, powered by the battery, while the gas/petrol engine remains shut off. A gas/petrol engine cannot produce high torque in the low rpm range, whereas electric motors can – delivering a very responsive and smooth start.
    01-hybrid-system-concept cars-gasoline electric mechanical hybrid system

    Ultimate Eco Car Challenge | Development of Ultimate Eco Car

    01-ultimate_eco_car-developments of hybrid technology-development of hydrogen fuel-fuel cell-hybrid technology
    Continuous improvement in conventional engines, including lean-burn gasoline engines, direct injection gasoline engines and common rail direct-injection diesel engines, as well as engines modified to use alternative fuels, such as compressed natural gas (CNG) or electricity (for Electric Vehicle).
    Engineers may disagree about which fuel or car propulsion system is best, but they do agree that hybrid technology is the core for eco-car development.
    01-ultimate_eco_car-diesel hybrid-fuel cell vehicle-alternate fuel hybrid vehicles
    “Plug-in hybrid” technology brings further potential for substantial CO2 emissions reductions from vehicles. It has a higher battery capacity and is thus more fuel-efficient than the current hybrid, assisted by the power of engine. For a short-distance drive, it could be run with electricity charged during the night. Depending on how electricity is generated, the vehicle could run with much lower CO2 emissions. In order to commercialize the plug-in hybrid, there is again a need for a breakthrough in battery technology. It is necessary to develop a smaller-sized battery with higher capacity. Plug-in hybrids could contribute to reducing substantial amounts of CO2 emissions from vehicles, as well as fossil fuel use, by charging from cleaner electricity sources in the future. 
    Challenges of increasing power performance
    In order to improve the driving performance, its power train was completely redesigned. To increase motor output, a high-voltage power-control was adopted. Although this technology was used in industrial machines and trains, the idea of incorporating it into an automobile did not easily occur at first. First of all, the system itself would take up a substantial amount of space and secondly, there was no prior example of applying this method to a motor that switches between output and power generation at such a dizzy pace. 
    Once the development of the high-voltage power circuit began, there was a mountain of problems, such as what to do about the heat generated by increasing voltage and the noise generated. To reevaluate the power train, the project team had to produce prototypes and repeat numerous tests. The prototyping stage went to seven prototypes instead of the usual three, and the total distance driven by these prototypes during testing

    Fuel Cell Technology

    The fuel cell vehicle (FCV) is the nearest thing yet to an "ultimate eco-car" that offers solutions to energy and emissions issues.

    01-fcc-car-fuel cell car-fuel cell technology
    FCVs are powered by fuel cells, which generate electricity from hydrogen, which is not only environmentally friendly and highly energy-efficient, but can also be produced using a variety of readily available raw materials. Thanks to these characteristics, fuel cell vehicles are ideal for achieving sustainable mobility. Therefore, Toyota is striving to make this vehicle technology widely available as soon as possible.
    01-fuelcell_vehicle - FCV-ultimate Eco car-Hybrid technology
    • Successful startup: -30° Celsius
    • Extended cruising range: 830km (JC08 mode) without refueling
    At a steady cruising speed, the motor is powered by energy from the fuel cell. When more power is needed, for example during sudden acceleration, the battery supplements the fuel cell’s output. Conversely, at low speeds when less power is required, the vehicle runs on battery power alone. During deceleration the motor functions as an electric generator to capture braking energy, which is stored in the battery.
    01-fuel cell animation-how fuel cell works
     
     
    01-schematic arrangement of basic fuel cell concept-status of fuel cell technology

    World’s First Air-Powered Car | Zero Emissions

    India’s largest automaker is set to start producing the world’s first commercial air-powered vehicle. The Air Car, developed by ex-Formula One engineer Guy Nègre for Luxembourg-based MDI, uses compressed air, as opposed to the gas-and-oxygen explosions of internal-combustion models, to push its engine’s pistons. Some 6000 zero-emissions Air Cars are scheduled to hit Indian streets in August of 2008.
    01-air-car-zero emissions-first air powered car
    Barring any last-minute design changes on the way to production, the Air Car should be surprisingly practical. The $12,700 City CAT, one of a handful of planned Air Car models, can hit 68 mph and has a range of 125 miles. It will take only a few minutes for the City CAT to refuel at gas stations equipped with custom air compressor units; MDI says it should cost around $2 to fill the car’s carbon-fiber tanks with 340 liters of air at 4350 psi. Drivers also will be able to plug into the electrical grid and use the car’s built-in compressor to refill the tanks in about 4 hours.
    01-air-car-engine
    Of course, the Air Car will likely never hit American shores, especially considering its all-glue construction. But that doesn’t mean the major automakers can write it off as a bizarre Indian experiment — MDI has signed deals to bring its design to 12 more countries, including Germany, Israel and South Africa.

    Air-Powered Car Coming to Hit 1000-Mile Range

    The Air Car caused a huge stir when we reported last year that Tata Motors would begin producing it in India. Now the little gas-free ride that could is headed Stateside in a big-time way.
    01-aircar-air powered car-zero pollution motor-tata motors-hit 1000 miles
    Zero Pollution Motors (ZPM) confirmed on Thursday that it expects to produce the world’s first air-powered car for the United States by late 2009 or early 2010. As the U.S. licensee for Luxembourg-based MDI, which developed the Air Car as a compression-based alternative to the internal combustion engine, ZPM has attained rights to build the first of several modular plants, which are likely to begin manufacturing in the Northeast and grow for regional production around the country, at a clip of up to 10,000 Air Cars per year.
    And while ZPM is also licensed to build MDI’s two-seater One CAT economy model (the one headed for India) and three-seat Mini CAT (like a Smart For Two without the gas), the New Paltz, N.Y., startup is aiming bigger: Company officials want to make the first air-powered car to hit U.S. roads a $17,800, 75-hp equivalent, six-seat modified version of MDI’s City CAT (pictured above) that, thanks to an even more radical engine, is said to travel as far as 1000 miles at up to 96 mph with each tiny fill-up.
    01-aircar-production-launching next year-guy negre, MDI, Motor development International
    We’ll believe that when we drive it, but MDI’s new dual-energy engine—currently being installed in models at MDI facilities overseas—is still pretty damn cool in concept. After using compressed air fed from the same Airbus-built tanks in earlier models to run its pistons, the next-gen Air Car has a supplemental energy source to kick in north of 35 mph, ZPM says. A custom heating chamber heats the air in a process officials refused to elaborate upon, though they insisted it would increase volume and thus the car’s range and speed.
    "I want to stress that these are estimates, and that we’ll know soon more precisely from our engineers," ZPM spokesman Kevin Haydon told PM, "but a vehicle with one tank of air and, say, 8 gal. of either conventional petrol, ethanol or biofuel could hit between 800 and 1000 miles."
    Those figures would make the Air Car, along with Aptera’s Typ-1 and Tesla’s Roadster, a favorite among early entrants for the Automotive X Prize, for which MDI and ZPM have already signed up. But with the family-size, four-door City CAT undergoing standard safety tests in Europe, then side-impact tests once it arrives in the States, could it be the first 100-mpg, nonelectric car you can actually buy?

    Variable Turbo Chargers Geometry (VTG)

    Variable geometry turbochargers (VGTs) are a family of turbochargers, usually designed to allow the effective aspect ratio (sometimes called A/R Ratio) of the turbo to be altered as conditions change. This is done because optimum aspect ratio at low engine speeds is very different from that at high engine speeds. If the aspect ratio is too large, the turbo will fail to create boost at low speeds; if the aspect ratio is too small, the turbo will choke the engine at high speeds, leading to high exhaust manifold pressures, high pumping losses, and ultimately lower power output. By altering the geometry of the turbine housing as the engine accelerates, the turbo’s aspect ratio can be maintained at its optimum. Because of this, VGTs have a minimal amount of lag, have a low boost threshold, and are very efficient at higher engine speeds. VGTs do not require a waste gate.
    01-variable turbine geometry-turbocharger-vtg-sequence
    Most common designs
    The two most common implementations include a ring of aerodynamically-shaped vanes in the turbine housing at the turbine inlet. Generally for light duty engines (passenger cars, race cars, and light commercial vehicles) the vanes rotate in unison to vary the gas swirl angle and the cross sectional area. Generally for heavy duty engines the vanes do not rotate, but instead the axial width of the inlet is selectively blocked by an axially sliding wall (either the vanes are selectively covered by a moving slotted shroud, or the vanes selectively move vs a stationary slotted shroud). Either way the area between the tips of the vanes changes, leading to a variable aspect ratio.
    01-normal_turbo charger-vtg turbo-turbine section-compressor section
    Actuation
    Often the vanes are controlled by a membrane actuator identical to that of a waste gate, however increasingly electric servo actuation is used. Hydraulic actuators have also been used in some applications.
    01-Twincharger_theory-turbocharger layout diagram
    Main suppliers
    Several companies supply the rotating vane type of variable geometry turbocharger, including Garrett (Honeywell), Borg Warner and MHI (Mitsubishi Heavy Industries). The rotating vane design is mostly limited to small engines and/or to light duty applications (passenger cars, race cars and light commercial vehicles). The only supplier of the sliding vane type of variable geometry turbocharger is Cummins Turbo Technologies (Holset), who are effectively the sole supplier of variable geometry turbochargers for applications involving large engines and heavy duty use (i.e. trucks and off highway applications).
    01-turbo-parts-turbocharger section-compressor air discharge
    Other common uses
    In trucks, VG turbochargers are also used to control the ratio of exhaust re-circulated back to the engine inlet (they can be controlled to selectively increase the exhaust manifold pressure exceeds the inlet manifold pressure, which promotes exhaust gas recirculation (EGR)). Although excessive engine back pressure is detrimental to overall fuel economy, ensuring a sufficient EGR rate even during transient events (e.g. gear changes) can be sufficient to reduce nitrogen oxide emissions down to that required by emissions legislation (e.g. Euro 5 for Europe and EPA 10 for the USA).
    01-turbocharger-Vtg-cross sectional diagram-control system
    Another use for the sliding vane type of turbocharger is as downstream engine exhaust brake (non-decompression type), so that an extra exhaust throttle valve isn’t needed. Also the mechanism can be deliberately modified to reduce the turbine efficiency in a predefined position. This mode can be selected to sustain a raised exhaust temperature to promote "light-off" and "regeneration" of a diesel particulate filter (this involves heating the carbon particles stuck in the filter until they oxidize away in a semi-self sustaining reaction – rather like the self-cleaning process some ovens offer). Actuation of a VG turbocharger for EGR flow control or to implement braking or regeneration modes generally requires hydraulic or electric servo actuation.