The new HELAX hydraulic-electric linear actuator from Bucher Hydraulics produces straight-line movements in the 20 kW to 300 kW power range with precision and maximum efficiency, and it opens up new fields of application.

HELAX stands for hydraulic electric linear axis based on AX Technology. HELAX is a hydrostatic transmission that converts electrical energy into hydraulic energy with maximum efficiency and offers linear movements with high precision. These application-specific system solutions not only set new technological standards, but also make a major contribution to sustainability.
Source: Bucher HydraulicsSource: Bucher Hydraulics

Central to HELAX is the four-quadrant-capable AX pump. Due to its unique design, it can map the entire operating range of servo motors with outstanding efficiency: even at very low speeds, the pump has almost no mechanical friction (starting efficiency up to 99%). The HELAX therefore masters the problem of generating large forces at close to zero speed — an operating point that is critical or even forbidden for many other linear actuators. Not so with HELAX, because where there is almost no friction, there is almost no wear.

This hydrostatic transmission, in which friction has been very significantly reduced, thus facilitates precise control of large forces over small distances, as the inverse pendulum illustrates.

In stationary plant, there is a wide range of potential applications: the highly efficient, low-friction hydrostatic transmission ensures precise control of linear movements, even with large forces and alternating load direction. This opens up new possibilities for the process technology used in production machines and testing equipment, with particular regard to component quality, throughput time and service life. Due to its modular design, the HELAX system solution can be easily adapted to a wide range of cylinder dimensions.

In electrically powered mobile machines, losses are systematically reduced to a minimum. For example, while a conventional pump may exhibit a power loss of 5.2 kW, with the new Bucher Hydraulics AX pump, the power loss under the same conditions is only 1.6 kW. Particularly with battery operation, this saves on expensive battery capacity. Either the battery can be made smaller and cheaper, or its runtime can be extended by a corresponding amount, as modeling calculations and initial experience have verified.

The HELAX linear drive is also highly suitable for applications where energy can be recovered. In these cases the impact of the regenerative linear drive's high efficiency (overall efficiency up to 84%) on the energy balance is quadratic, in fact, thus enabling energy recovery in applications where previously this was not economically viable.

The on-board electronics ensure that the linear transmission can be easily controlled by the machine builder. The motion control signals are transmitted via CAN bus, for example: the software then converts the signals into the required movement. Users do not have to get involved with the detailed characteristics of the hydraulic system: they can concentrate fully on the function of their application. The hydraulic linear drive can therefore be easily integrated into the system just like any electric drive.

Thanks to its modular design, the HELAX system solution can be very easily adapted to a wide variety of cylinder types. The new AX pump from Bucher Hydraulics supplies the system with controlled flow rates without any throttling losses.

For more information, visit the Bucher Hydraulics website.

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