gearchange

Whether the gearchange function can be used for more than two spindle ranges.

you can add more then one gearchange fuinctions or vomponents
but you can also use a simple logic to do it

Here is a version I wrote years ago that handles up to 32 gears.

Install it with "sudo halcompile --install gearchange.comp"

That should also generate documentation.

Hi,

@andypugh do you have an hal example?
I want to use it for my lathe which has 24 gears (3x4 manually switched and and two by an electic controlled hydraulic clutch) To make this more fun I added a VFD and now need a way to scale the output.

thanks Patrick

The HAL setup would depend on how the system is configured to detect the selected gear.

For your setup I think that you would need some HAL logic to convert the 3 inputs into a gear number. Or you could modify the component to suit your system.

As it stands the component expects either an integer number for the selected gear, or a single input bit to be set for each gear. Your system has 8 inputs but they are used in combinations. You could potentially wire pairs of switches to each lever to give binary patterns to be sent to a weighted-sum component, but I think that modifying the component above to have three sets of input bits would be better.

It might actually be easier to use the VFD speed and measured spindle speed to auto-detect the selected gear. (Better still would be to use a speed sensor or encoder on the motor). This is what I do with my milling machine which has 8 gears.

Thanks for answering. Sensors for the mechanical lever would be difficult.The electric clutch would be no problem. The spindle to measure the spindle speed is no problem it has an encoder but I can't fit an encoder to the motor.

I found thread of yours:
forum.linuxcnc.org/47-hal-examples/27071...indle-gear-detection

but I didn't understand it completely yet

Maybe some sort of sensor detecting the motor fan blades?

This might not be necessary with a modbus-controlled VFD. The one on my mill is controlled by analogue voltage so I don't have the actual motor speed, just the commanded.

yea same here. just analog out. But I think it can talk modbus. but why would this be better compared to an analog control?
Couldn't I calculate from the voltage and the rpm of the motors it speed.
can't simply set the gear with an hal input

anfänger wrote: yea same here. just analog out. But I think it can talk modbus. but why would this be better compared to an analog control?

With Modbus the VFD reports back the current speed. With analogue control your motor speed is only the programmed speed once the ramp up and ramp-down have finished.

can't simply set the gear with an hal input

Is that a question or a statement? You certainly could enter the currently-selected gear in a VCP box and connect that to the gearchange comp in HAL, but that seems inelegant.

My lathe has only two gears, I think that I am glad about that (And I have managed to program it to switch speeds on-the-fly during G0 moves)

Yes it would be an quick and dirty solution. An alternative start would would be using 2400 and 1600 rpm with the electric clutch.
I am slowly getting an idea how I can build something to automatically change the manual gears