Crouzet just introduced two new products for the brush and brushless DC micromotors market. High added value products designed for quick and easy handling. These developments illustrate how Crouzet's offer is being adapted to meet the exacting requirements for critical application.
With 40 years of expertise in the field of motors, one of Crouzet's aims has been to produce a new catalogue of high performance solutions focusing on DC motors. Now, the company is making this dream a reality. Safety and reliability are the main focus of the developments. These considerations are particularly important given Crouzet's strategy of targeting the critical system applications in market such as medical, railway, aerospace and industrial. The new brushless motor can be recognised by the 57 mm square section on its front face and comes in three compact sizes offering output powers of 66, 90 and 150 Watts.
Like all Crouzet added-value motors, this high performance DC motor is made in France and is the result of almost three years' in-house research and development work. This range is opening up new horizons in the areas of speed, torque and positioning control for small stand-alone machines. It complements the functions provided by the Motomate solution, which features an integrated electronic control system that is capable of managing speed and torque.
Complete reworking of electromechanical design
With a nominal mechanical output power of 150 W (max. 240 W) at 24 volts, this brushless motor is the most powerful in its range. "This outstanding accomplishment has been made possible thanks to a complete redesign where attention to detail was the key to success. As part of this process, our product designers worked to minimise energy losses and improve heat dissipation", explains Michel Nicol, head of the Product Marketing Departement. The new design incorporates micron machined parts, optimal precision bearings and state of the magnets, that result in an electrical efficiency of 83% that testifies to the resounding success of the optimisation process. New brushless DC motor with built-in electronics
Parameter Definition for All
The new brushless motor programs are specifically designed for motion control that allow design engineers and end users to perform a single parameter definition operation and avoid the time consuming programming. A standard USB cable is now used to link the motor electronics to a PC on which the parameter definition software is installed. This software can be downloaded from the Crouzet website as of January 2012. "We really wanted to go down the route of making configuration transparent and easy so that the user does not even have to read the motor documentation", explains Michel Nicol. In addition to providing application programs, Crouzet has inserted a parameter definition which enables the integrator to fine tune the program to meet the specific application needs. Highly intuitive, the program uses the engineers knowledge of the application allowing them to introduce specific adjustments if need be. This is done through easy selection boxes or by adding physical values. Alternatively the advancing programming is accessible for engineers who wish to go further. Crouzet will provide new application programs as and when they are developed in the form of regular software updates.
Standard or Tailor-Made
Crouzet offers the standard software package and on request can also offer integrators tailormade parameter definition tools that are perfectly suited to their specific requirements. These tools may apply at an in-depth level or at the level of the user interface. Furthermore, integrators can use a "boot loader" function to replace the standard program that the motors load by default with a special version of the software. The Crouzet product designers are also able take into account specific electro-mechanical adaptations such as motor length, shaft connector and communication bus on request. The motors are equipped with 6 inputs (2 analogue + 4 AON) and 4 outputs (of which 2 are AON or PWM), enabling them to exchange commands with each other or other components such as PLCs. They are also available in combination with planetary and right angle gearboxes from the standard Crouzet range. The new motor itself incorporates a 4096-point encoder with the new Smi21 electronics unit (not a PLC) featuring several ready-to-run programs.
Positioning for Small Stand-alone Machines
The new brushless motors are particularly suitable for small standalone machines which perform positioning or metering functions. When used in this context, the motors make effective use of a voltage between 9 and 56 VDC for both the drive and control electronics. There is an integrated switch mode power supply for this purpose. "We went to great lengths to design a motor capable of running on a 12 volt battery. What's more, the increased efficiency of the motor and its low power consumption in the idle mode do not compromise the machine's autonomy!" In the idle mode, the electronics only consume 40 mA at 24 V, which is less than 1 W. Comparable motors on the market consume between 2.5 and 5 W in the same conditions. The field of application not only encompasses machines in the medical, industrial and energy sectors but also those in the food processing, military and transport sectors. The new generation of brush motors involved taking the current design back to the drawing board. It comprises 15, 25 and 53 W motors with a 42 mm diameter and 55 and 99 W motors with a 63 mm diameter that correspond to the dimensional standards of the current range. As of January 2012, the existing products will be supplemented by high-end IP65 and IP66 or IP67 versions with enhanced features.
Silence! Do not Disturb!
With a noise level of 40 dB(A), compared with 55 dB(A) for the current standard range, the new motors clearly benefit from the careful work done during the design phase: the quality of the magnetic steel sheets and brushes, the shape of the rotors poles and the balancing are all factors which help dramatically reduce the energy dissipated through vibration and the level of resonance. The noise level of the motor is significantly lower as a result. "Key components, such as the collector are machined to an accuracy of 1 or 2 microns. This goes hand in hand with the new brush supports, higher class ball bearings and high-quality magnets", explains Michel Nicol. Better still, Crouzet asked the geared motor group to tackle the problem of noise levels. As a result, new low-noise planetary gearboxes have now been included in the catalogue. "We made a special effort to align the motor and the gearbox both in terms of perpendicularity and concentricity. This is why the motor and gearbox combined produce less than 55 dB(A) whilst keeping the effect on the mechanical resistance to a minimum."
Increased Service Life
Thanks to their high quality of manufacturing process the new DC brush motors offer a minimum service life of 5000 hours when used at nominal power. Under reduced load conditions, this can be increased to up to 10,000 or even 20,000 hours.
Environmental Impact Reduced by Half
Thanks to its incisive eco-design strategy, Crouzet has succeeded in halving the environmental impact of its new brush motors with regard to their overall life cycle. Furthermore, the quality of the magnetic circuit and the reduced losses ensure greater energy efficiency.
For discreet applications...
Because they are silent even under full load, the motors/geared motors are perfect for applications where machines are specifically intended for medical use. They are also relevant to the applicable standards in the medical (CEI 60601-1) and office equipment (CEI 60335) sectors as well as those covering household appliances (CEI60335). The new motors are approved in accordance with UL/CSA 1004-1.
And always adaptable
The Crouzet product designers are able to add accessories to the motors in order to accommodate specific needs. Such additional modifications may include a rear brake, 1000-point 2-channel encoder, special connectors, new shaft dimensions and/or materials and modifications to the motor length. Further gear ratios can also be offered. In addition, the motors can be adapted to suit railway applications, meeting compliance with fire/smoke regulations. Customers can also request other motors colors if need be.