Drives For Medical Devices

Video: Drives For Medical Devices

2023 Author : Hannah Pearcy | [email protected] . Last modified: 2023-06-05 00:21

Whether dental chairs with their adjustable neck supports, diagnostic devices and computer tomographs or X-ray and therapy devices for movement exercises - there are numerous drive systems in medical devices with different requirements. Lighting systems in the operating room, automatic adjustment devices on operating tables and stairlifts or the like are also included.

Compact drives with comparatively low power are often required, which have to work very reliably and with high positioning accuracy. Longevity, low-noise running, dynamics and precise speed control are further requirements that have to be met. With the individually configurable ECI-42 drives, EBM-Papst offers the right variant for every application, which can be combined with different, tested and validated modules such as brakes, gears and encoders, etc.

Picture gallery

The heart of all configurations is a brushless, electronically commutated inner rotor motor with a diameter of 42 mm and overall stator lengths of 20 or 40 mm. It achieves outputs of around 45 W or 90 W at 110 mNm or 220 mNm nominal torque and 4000 min ^–1 nominal speed. The efficiency is up to 80%. The motors are available as standard in 24 V DC and 48 V DC protective extra-low voltage versions. Hall sensors for rotor position detection are currently integrated and the motor is controlled by an external controller. Integrated electronics modules with functions such as speed or position controllers, optionally with a BUS interface, are under development at EBM-Papst.

Select suitable transmission and brake modules

Various gear modules are available to reduce the high speeds of the internal rotor drives and to bring the output torque to the level appropriate for the application. In addition to planetary and spur gear units with different reduction ratios, the space-saving Eta-Crown angular gear units based on the innovative crown gear technology are also available. EBM-Papst guarantees very quiet operation with the planetary gearbox Noiseless Plus 42. With the Optimax-42 gearbox, a robust and overload-proof one- or two-stage planetary gearbox with protection class IP50 or optionally IP54 is also available for the small 42mm drives.

User meeting mechatronic drive technology

Your way to an efficient powertrain

If the application requires holding or safety brakes for a quick emergency stop or in order to hold the position securely in the case of a lifting device in the event of a supply voltage failure, modules with permanent magnet or spring-applied brakes can supplement the drive unit. This means that there is no risk to the patient. In the case of X-rays, the positions can be held precisely and securely over a long period of time.

Book tip

The book Drive Design Practical Guide helps you select the essential components of electrical drive systems: motor, gearbox, actuator, power supply and their additional components. The calculation is also dealt with intensively.

Position detection with encoder

An encoder module can be integrated into the drive unit for precise position detection. The magnetic incremental encoder works with a resolution of 12 bits, which increases depending on the selected gear solution, so that an accuracy on the output shaft of up to 0.08 ° can be achieved. Smaller resolutions are also possible.

In the next stage of expansion there will also be an absolute multiturn module (up to 17 bit resolution in the singleturn and up to 32 bit in the multiturn area). The revolution counter works without batteries, instead it uses an energy harvesting system based on the Wiegand effect. The energy required for the storage of the rotation information is thus obtained from a rotating magnetic field. This makes backup batteries, gearboxes and associated maintenance measures unnecessary.

User meeting mechatronic drive technology

The focus of the user meeting mechatronic drive technology is on the mechanical components of gears, clutches and brakes as well as their design, dimensioning and interaction in the overall mechatronic system.

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Different electrical connections possible

The individually compiled 42 mm drives from the EBM-Papst drive system also offer variable options for electrical connection. These include, for example, industrial plugs in which the radial right-angled plug with a bayonet lock can be rotated and automatically snaps into place. An axial connector is available for space-critical applications; alternatively, a pre-assembled cable connection is also possible.

The drives are suitable for practically all applications in medical technology that require energy-efficient small drives. Due to the defined preferred types, selected drive configurations are ready for dispatch within 48 hours. For example, samples can be implemented in a short time. The drives can be configured and ordered via the online portal idt-config.ebmpapst.com.