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Absolute encoder with integrated electronic cams

The NocTivo series Baumer IVO comprises absolute encoders with integrated electronic cams featuring a compact design of 75 mm in diameter and 50 mm in length. The standard hollow shaft singleturn encoder utilizing a 13 bit resolution what corresponds to 8192 positions. 16 programmable short-circuit proof cam outputs are available at the parallel interface. Four inputs serve for selecting one of the 16 programs, another input signal is starting the selected program. 16 outputs and 16 programs enable programming of max. 1024 cams. Both direction and time-relevant cams are available, i.e. trigger for on and off can be assigned not only to a position but also to the sense of rotation and time if required. The cam encoder features a power of max. 500 mA per output what allows direct switching cycles of even superior loads without additional signal amplification. Time lags in the switching cycle can optionally be equalized by convenient and user-friendly programming. The cam encoder communication with for example PC or notebook with installed software ProCam is realized by RS232 respectively RS485 interface. The open programming interface is further enabling programming by customer-specific protocols or directly by PLC. Further features are planned for the future, for example a shaft design and compatibility to several fieldbus systems by the modular Bus cover concept already well-proven in the multiturn encoder series.
Many tasks in automation call for position-relevant switching cycles and consequently have been for long the domain of cam gears. Mechanical solutions susceptible to wear and tear meanwhile have been replaced by electronic cam gears opening up new possibilities for the operator, especially thanks to their flexible programming options.
With regard to decentralized structures there is a new trend in modern engineering technology. Due to very high processing speeds, especially the packaging industry is focusing on solutions where the electronic cams are integrated in the absolute encoder that is required anyway. The cam encoders of the latest generation are especially convincing by their compact design, high resolutions, powerful outputs, versatile programming functions and thanks to their fieldbus capability they can be integrated into master automation landscapes.

First step: Replacing mechanics susceptible to wear and tear by electronics

Mechanical camshaft gears have been more and more replaced by electronic solutions. Electronics means speed, no wear and tear and most of the time convenient and easy operation. Furthermore electronic cams feature many different programs that at any time- even during operation- may be amended or adapted. By principle, cam gears may be part of a control program, but not in time-relevant tasks since even a rapid PLC is subject to prolonged cycle times according to the increasing program complexity. For this reason, integrating a camshaft gear into the control level for applications in the mechanical and plant engineering industry does not make sense.
Second step: Encoder with integrated cams functions
You can imagine each output of an electronic cam gear as „unrolled circular circumference” of a mechanical cam. The number of “cam discs” corresponds to the number of outputs. Cam programming is by keypad to define the corresponding triggers for on and off. Machine position sensing is by encoder, in general absolute, which is passing the absolute angular value of the machine position to the electronic cam gear. Meanwhile, following the trend towards decentralization, electronic solutions are well established in mechanical engineering and plant technology.
Technical progress never stops. Integrating the electronic cam gear into the absolute encoder that is required anyway does not only mean saving completely one device, space and corresponding mounting costs but even better this solution is eliminating trouble occurring in the connection between encoder and cam gear that often is susceptible to disturbance and interferences. By corresponding interfaces the cam encoder is allowing direct communication with the master control or PLC. Errors and malfunctions for example can be traced easily.

Hollow shaft encoder with high-performance cams
By RXA1H, Baumer IVO as an encoder specialist offers a compact absolute encoder featuring electronic cams. The absolute encoder with dimensions of 75 mm in diameter and 50 mm in length is already having the fully electronic cam gear integrated and thus already in the standard version allows many “intelligent” control functions.
The hollow shaft singleturn encoder with electronic cams is allowing quick and easy mounting onto the drive even in narrow places difficult to access. The cam encoder requires only two mounting accessories: fixing angle or leaf spring as torque support and one mounting screw. Just slide the encoder onto the shaft and tighten the clamping ring, what is done within a minute even without any practice.

High resolution and many optional function already in standard version
The singleturn hollow shaft encoder with electronic cams features a standard resolution of 13 bit what corresponds to 8192 positions. The parallel interface is providing 16 cam outputs protected against short circuits. Four inputs serve for selecting one of the 16 programs, another input signal is starting the selected program. The 16 outputs enable programming of up to 1024 cams (fig.6), both direction and time-relevant cams (fig. 7 and 8). In other words, the triggers for switch on and off are not limited to position but can also be assigned to sense of rotation and time if required. The cam encoder provides a maximum drive output power of 500 mA, whereas 1.5 A per block of eight must not be exceeded. This is enabling direct switching cycles also of superior loads without additional signal amplification.
The cam encoder is capable of time lag compensation. If required, the trigger for on and off of the programmed cam is shifted depending on the actual speed. This means compensating the time elapsed from output trigger to the true reaction. Programming is easy and practice-oriented. The cam encoder is able to communicate with PC or notebook having the software ProCam installed by RS232 resp. RS485 interface.
ProCam is an especially modified windows software for easy application with versatile visual options. By serial interface the actual speed can be shown on the screen any time upon request. The cam encoder is designed for industrial applications and in line with protection standards IP 54 to IP 65. Supply range is within 12 and 30 V so that peaks and drops in the mains are not a problem. Already the standard version offers outputs that may be assigned to several special functions, for example run control signal or watchdog for monitoring or warning upon exceeding the rotation speed. Upon request a LED for zero point indication may be integrated.