abs and abs supersteer -...
TRANSCRIPT
ABS and ABS SuperSteerTM
LEADING SAFTEY IN AGRICULTURE
Name
Introduction ABS Brakes
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Road SafetyTransport tasks have radically changed in Agriculture over the last decade
Speeds have increased along with tractor power. 50kph even with a full load is quickly reached which places more burden on the brakes
Those customers carrying out a large amount of haulage work are looking to operate to a high degree of safety. These customers will predominantly be operating with pneumatic brakes and possibly front axle brakes today. ABS is their next step that brings an additional level of safety and control.
New Holland is the first manufacturer to offer ABS on a conventional tractor
ABS Benefits
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The aim of ABS is to maintain traction between the tyre and the road surface. This prevents the wheels locking up causing skidding and importantly maintains steering control
ABS will provide straight line braking even if the left wheels are on a different surface to the right
ABS delivers the ability to brake hard while steering around an obstacle
ABS Components
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The New Holland ABS is based on a pneumatic system, leveraging experience from the truck industry
Main components to be installed over the current pneumatic air system are:-
•Larger air reservoir capacity
•Water cooled compressor
•Dedicated brake circuit and air brake circuit
•Electronic Control Unit to control brakes and ABS
•ABS distribution valve
•Pneumatic over hydraulic actuators x 3
•Speed sensors for each wheel
ABS Layout
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Air Hydraulic actuators1 x Front axle2 x Rear axleIndividual fluid reservoirs
Pneumatic foot valve
Individual wheel speed sensors
Air processing unit
Increased reservoir capacity
Electronic Brake Module
Water cooled air compressor
ABS Components
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Control switch
ABS On/OffCan be switched off below 40 kph
Independent Braking
A single foot valve controls the braking, independent braking however is still possible but is electronically obtained when the brake pedal is unlatched. Like a conventional system the wheels can lock up while using the independent brakes. At speeds over 12 kph an electronic latch activates so that either pedal operates all four brakes
Large capacity water cooled air compressor supplying a larger reservoir. Required to meet the higher pneumatic demand of the ABS
Air treatment unit incorporates a drier and heater
ABS Components
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Air brake pressure from the foot valve is converted to hydraulic pressure using three air over hydraulic converters. Two for the rear axle (located in a fuel tank recess) and one for the front axle (located in front of the fuel tank). Hydraulic pressure can then be modulated to control the conventional tractor brakes
Additional brake fluid reservoirs for independent circuits. One located in front of fuel tank the other located beneath the left hand door
Wheel speed is detected by the four sensors located in the front axle beam and rear trumpet housings
Guard removed
ABS Constraints
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The New Holland ABS system can be fitted to any T7. LWB Power Command or Auto Command but requires the following features:-
SideWinder II
Electronic Park Brake
Front axle suspension with front brakes
Pneumatic trailer brakes
Battery Isolator
A T7 with ABS is fully compatible with any hydraulic or pneumatic trailer brake systems, ABS is not required on the trailer
SideWinder II
EPL
Front suspension + Brakes
ABS SuperSteer
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New Holland HeritageNew Holland has a history of introducing steering innovations
Steering -O-Matic for crawlers, FastSteer for reducing steering wheel movement and SuperSteer.
SuperSteer obtains the best in class turning circle by swinging the complete front axle as well as the hubs to achieve up to 65 degree turn angle
Customers however have not been able to choose the extra manoeuvrability of SuperSteer as well as a front axle suspension system
ABS offers an opportunity to obtain the best manoeuvrability while also having front axle suspension. This new optional feature over the standard ABS is called ABS SuperSteerTM
SuperSteer
ABS SuperSteer
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Awarded a Silver medal at Agritechnica in 2009, ABS SuperSteer combines modern technology with a long established method of assisting tractor turning, the independent brakes
Independent brakes are traditionally used to help tractors turn tighter, especially in greasy conditions. The negatives are that it can apply stress to the driveline and usually results in a wheel locking up causing soil damage through smearing
By applying the technology incorporated into the ABS system we can harness independent braking to reduce turning circles without any stress or soil damage
Soil damage through smearing
Traditional independent brake steering
ABS SuperSteer
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ABS SuperSteer can be operated in two modes
1. ABS SuperSteer - Steering wheel mode
When activated the driver steers normally but as he turns the inside wheel’s brake will be applied. The ABS wheel sensor is used to finely control the brakes, ensuring the wheel is always rotating and avoiding soil damage
Sensitivity can be adjusted on a screen within the IntelliView III
Up to 50% smaller turning circle can be achieved with ABS SuperSteer
Minimum Soil disturbance
ABS SuperSteer
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ABS SuperSteer can be operated in two modes
2. Steer by ABS - Brake pedal mode
Unlatching and pressing the left or right hand pedal will activate independent braking, as with the standard ABS, but the wheel rotation will be monitored and brake pressure regulated to avoid a wheel lock up.
Sensitivity can be adjusted on a screen within the IntelliView III
Independent braking without soil damage Minimum Soil disturbance
Hill Holder
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Another feature with ABS SuperSteer is Hill Holder
Hill Holder applies to the Power Command tractors only*
Hill Holder provides assistance for hill starts by holding the brakes on while the driver’s foot transfers from the brake pedal to the throttle pedal
Brakes are held until clutch pedal starts to be released
Avoids the risk of tractor rolling backwards and reduces risk of stalling the engine
Hill Holder, an additional safety feature of ABS SuperSteer
*Auto Command models already feature active stop/start through the CVT
ABS SuperSteer Benefits - Video
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Unstable emergency stop Controlled emergency stop
Jack Knife caused by wheels locking Wheels always rotating, no jack knife
http://www.youtube.com/watch?v=4PuN-JZnIZI
T7 ABS
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