Integrated Continuously Variable Drive
Integrated Continuously Variable Drive
OUR SOLUTION!
Walterscheid has developed a continuously variable, hydrostatic travel drive for self-propelled agricultural and construction machinery.
- The ICVD® (Integrated Continuously Variable Drive) makes it possible to drive through the entire speed range without interrupting the tractive force.
- The ICVD® is thus a symbiosis of time-proven drive concepts, combining their advantages, but without having to accept the drawbacks of the old solutions.
- The ICVD® is the only continuously variable, hydrostatic travel drive to use 45° large-angle technology and comprises a gearbox, a hydraulic motor and a control unit.
ICVD S1N 370V: Energy-efficient and comfortable
The new continuously variable travel drive ICVD S1N 370V provides convincing answers to growing requirements in terms of tractive force, speed and energy efficiency of agricultural and construction machinery. Tractive force is provided through the entire speed range up to 40 kph without a shifting process or interruption. This ensures high user comfort and also has significant effects with regards to energy efficiency.
That is particularly true for full vehicle power management systems with one motor powering different components. As no friction clutches or additional hydraulic motors are required, this technology also delivers convincing results in terms of reduced drag-torque and costs of the system in comparison to multi-motor concepts.
A standard control component which already is in use in other drives was integrated into the new continuously variable travel drive. This offers various control options and ensures perfect compatibility with available controller and software interfaces. In addition, the use of this high-volume component allows for maximum ruggedness and reliability of the new continuously variable travel drive.
Despite the extremely compact dimensions of hydraulic motor and gearbox, and a weight of approximately 200 kg, the high-performance travel drive offers a convincing power capacity of 130 kW. The ICVD P370 is based on a bent axis motor kit with corresponding swivel mechanism and control unit and was developed for trouble-free application in a wide range of agricultural and construction machinery.
The ICVD P370 was designed in a joint development project by Walterscheid and Danfoss Power Solutions as a key partner, thus allowing for a systematic and holistic approach. Walterscheid Powertrain took particular responsibility for construction, manufacturing and test bench trials whilst Danfoss Power Solutions provided technical expertise as well as support for system and component integration especially during the development phase and vehicle testing.
Design
The design of the ICVD® meets two essential requirements: compact and modular. This makes it possible to realise highly flexible and inexpensive drive solutions in practice.
The ICVD® consists of a control unit, the gearbox (mechanical drive) and a hydraulic motor. This compact assembly is universally adaptable in the vehicle, directly on the axle or on the vehicle frame.
The ICVD® is currently available in performance classes with different torques, allowing manufacturers to equip their entire machine portfolio.
The specified performance parameters for tractive power, engine output and speed decide the version to be used, which is then individually configured by the ICVD engineers on the basis of vehicle-specific parameters.
The entire range has a modular structure so that it is not only possible to realise individualised customer solutions but, in addition, common parts standardised according to the modular design principle are also available. These include core elements, such as the control unit, the swivel bracket and the drive, as well as blanks for internal parts.
Benefits
The ICVD® possesses a number of design features that add up to a totally new travel drive.
At the heart of the ICVD® concept is the use of a hydraulic motor featuring „large-angle technology“. This permits pivoting of the motor up to an angle of 45°, instead of the usual maximum of 32°.
Both the hydrostatic conversion range and the efficiency are substantially improved, making this technology a real alternative to the previous concepts.
As a result, a number of advantages can be achieved:
- Large, continuously variable conversion range
- Automatic adaptation of the power requirement
- Tractive power generation independently of the rpm speed
- Simple reversal of direction of travel and torque
- Flexible arrangement of the drive elements
The ICVD® can be used to realise very quiet drive concepts in practice. And the optimised efficiency also cuts the vehicle‘s fuel consumption
Continuously variable hydrostatic travel drive
Wider conversion range with large-angle technology
Reduced fuel consumption
Optimised efficiency due to integrated hydrostatic motor with large-angle technology
Low noise
Reduced tyre wear
ICVD Model Range
For manufacturers of agricultural and construction machinery, as well as municipal vehicles, Walterscheid offers a modular range that also allows the realisation of individual customer solutions. The current range comprises five versions with different power ratings, with which manufacturers can equip their entire machinery portfolio.
ICVD® GT-S1N-233V
Max. volume = 233 ccm
Max. operating pressure (Δ p) = 480 bar
Max. torque = 2.560 Nm
Max. speed of drive shaft = 4.470/min
Transmission ratio = 0,94 – 1,6 : 1
Conversion range = 8 : 1
ICVD® GT-S1A-233V/…
Max. volumen = 233 ccm + 60 ccm
Max. operating pressure (Δ p) = 480 bar
Max. torque = 3.200 Nm
Max. speed of drive shaft = 4.470/min
Transmission ratio = 0,94 – 1,6 : 1
Conversion range = 10 : 1
ICVD® GT-S1 A 233V-K*
Max. volume = 233 ccm + 60 ccm
Max. operating pressure (Δ p) = 480 bar
Max. torque = 3.200 Nm
Max. speed of drive shaft = 4.470/min
Transmission ratio = 0,94 – 1,6 : 1
Conversion range = 10 : 1
* Optionally with axle disconnection*
ICVD® GT-S1N-370V
Max. volume = 370 ccm
Max. operating pressure (Δ p) = 480 bar
Max. torque = 4.250 Nm
Max. speed of drive shaft = 3.872/min
Transmission ratio = 0,96 – 1,67 : 1
Conversion range = 8 : 1
ICVD® GT-S1N-370V-K*
Max. volume = 370 ccm
Max. operating pressure (Δ p) = 480 bar
Max. torque = 4.250 Nm
Max. speed of drive shaft = 3.872/min
Transmission ratio = 0,96 – 1,67 : 1
Conversion range = 8 : 1
* Optionally with axle disconnection*
REFERENCES
Following exhaustive test phases, many equipment manufacturers are now using the ICVD® in practice.
More efficient wheeled loader use
For example, KRAMER uses the new travel drive in its wheeled loaders. This is what Kramer’s development engineers write:
“The new Kramer Allrad loader is optionally equipped with the ‘Ecospeed’ continuously variable overdrive gearbox, with which Kramer Allrad currently has a unique position on the international wheeled loader market. In this most powerful drive version, the machine reaches a top speed of 35 km/h! But in addition, the overdrive has even more advantages: noise emission is lower, the engines consume considerably less fuel. Above all, though, the ‘Ecospeed’ gives the wheeled loader optimum tractive power in the entire speed range – that is unique in the industry!”
And “new” arguments count too
“Even in today’s urban traffic, a machine that goes no faster than 20 km/h is a hindrance to traffic. There are so-called high-speed machines that do up to 40, but to reach top speed they have to change straight into second gear from a standstill. That can be a problem on hilly terrain with a trailer, especially if you have to do a hill start. In contrast, the driver with Ecospeed transmission can ‘relax’. He can go from zero to 40 without even changing gear, and with full tractive power in every situation.
“The transmission is not only safe and easy to operate – as is the case with ‘normal’ hydrostatic transmissions, too, incidentally – but the greater overall efficiency also has a positive effect on fuel consumption!”
Higher loading capacity and speedy travel CLAAS uses the ICVD® for the latest generation of Scorpion telescopic loaders.
This is what the Claas developers write:
“The convincing handling properties of the SCORPION are attributable to its intelligent VARIPOWER drive. It consists of a gearbox, a hydrostatic motor based on large-angle technology (45°), and the corresponding control elements. Speed and pushing power are constantly and automatically coordinated with each other. When driving into a heap of material, the SCORPION distributes the force to precisely where it is needed. For even tougher demands, CLAAS also offers a PLUS version of the new VARIPOWER drive. In this case, the output is increased by an additional, fixed-displacement motor. The intelligent control system provides automatic power splitting, and that produces previously unknown driving performance.”
Attractive prospects
Expansion of the range of applications to include self-propelled agricultural machines, such as combine harvesters, choppers or beet lifters, and use in numerous construction machinery categories is currently being tested or realised.
DOWNLOADS
ICVD® Technical Handbook English
ICVD® Technical Handbook German
ICVD® Brochure English
ICVD® Brochure German
Watch the ICVD® in Action >