Spring brake or clutch control wish list fulfilled?

If you work in the world of spring brakes and clutches like I do you’ve probably developed an informal wish list over time of what the brake and control could do to make your life easier. Chances are these wishes fall into 1 of 2 categories; optimizing performance and improving reliability.

To optimize performance when disengaging a spring brake or clutch, we would ideally provide full voltage, 24V to a 24V brake, to the coil initially to overcome the spring force. However, once the armature has moved much less voltage is needed to hold the brake disengaged so maintaining that voltage wastes energy and heats the brake reducing its life. So in our ideal situation we would reduce the voltage to a holding voltage less than 24V after the initial full voltage time needed to fully disengage the brake or clutch. Again, ideally, both this full voltage time and holding voltage level would be easily and continuously adjustable to optimize them for any brake or clutch I wished to use. It would also be useful to have an indicator on the control, an LED that turned on when the brake was on, reduced in brightness proportional to the reduced holding voltage and turned off when the brake or clutch was off.

To keep going with making life easier we may also like to be able to receive a signal that tells us the status of the brake or clutch. Perhaps a voltage signal output from our control that we can monitor remotely from a control panel to know when the brake or clutch armature has actually begun movement. Rather than just assuming it has turned on (disengaged) when initiated we would receive a signal as positive feedback that the armature has, in fact, moved.

All this will get us our best performance and monitoring of our brake but at some point we know it will wear out and fail. In order to improve reliability, in our ideal situation, we would do maintenance exactly when needed. Trying to schedule maintenance has 2 inherent problems; doing it too soon or doing it too late. Performing maintenance entails down time of our system, tying up maintenance personnel, and fixing or replacing our brake or clutch. This is costly so we don’t want to do it more often than necessary. Yet it may not be as costly as not doing it often enough and risking system failure. If we schedule periodic maintenance (every 3 months, 6 months, etc.) we risk both types of problems. Perhaps the brake was used much less than usual the last 3 months so we may be replacing it unnecessarily, or if it’s been overused maybe it doesn’t quite make it to 3 months…uh-oh.

With our ideal control we don’t have to worry about doing it too soon or too late. What if the control had another signal, perhaps an LED indicator, to let us know when there were, say, less than 1,000 cycles remaining on our brake or clutch? That would be a nice, visual warning that I better schedule maintenance.

But maybe we can do even better, after all this is a wish list.

What if I could see exactly how worn my brake or clutch is? An actual display, an LCD screen, with a 2 digit readout of the actual percent wear on my brake or clutch. Now we’re talking, I’ll know when it’s 43% or 72% or 81% worn. With my brake monitored for wear every cycle and having it continuously displayed I can schedule maintenance when it reaches a specific worn condition. I can now establish my safety threshold. So if I decide the brake or clutch needs to be replaced or repaired at 80% wear I’ll know when I’m approaching that and can schedule maintenance, no concern that I’m wasting money doing it too soon nor risking doing it too late. If it was lightly used the last 3 months I would see it is only say, 10% worn, too soon to replace (saves that maintenance cost) or if heavily used I might see it at 80% worn in only 2 months (glad I didn’t wait).

So there’s a wish list for the ideal spring brake or clutch control;

• Adjustable full voltage time for optimum performance
• Adjustable holding voltage for longer life and reduced energy use
• Brake or clutch on indicator with brightness proportional to brake current
• Armature motion signal for positive feedback to integrate into my control system
• Warning light when less than 1,000 cycles remain for safety
• Display of armature wear to know exactly when maintenance is needed

Now this control is available, the SmartSense24, from Regent Controls. If you would like more information please contact us.