stepper motor from hp printer

[myxo]

Hi I got this stepper motor from an old HP printer. RH7-5219 DNQ16D16R37A .
I can't find any specifications on the web.
Its a 6 wire , so its unipolar. It measures approx 80mm in diameter and about 96mm long including the black part
It has 24 distinct steps when rotated by hand .
I compared it to another stepper from the same printer (NMB PM55L048-CAQ8) which is a 7.5 degree ,55mm motor, by counting the steps they were the same so I would assume it may also be a 7.5 degree motor.

The chip on the board it is attached to is LB1823 DK3.
Is that board the driver /controller ? I havent seen any motors with boards attached.

Can anyone help me with any info about the RH7 motor and possible its suitability for use in a cnc machine. I hope to build a small table top unit maybe 24"x18" for light aluminum and wood routing.

I also have a pic of the 2 motors side by side.
and a pic of the wire connectors
thank you

[packrat]

That is a 'BLDC' motor and chip. BLDC = Brush Less DC. Alot of printers have gone to them instead of stepper motors. Link to the chip - http://www.datasheetcatalog.org/data...f_e/LB1823.pdf

[LUCKY13]

I have a few different motors like those. What the PS and the LD hookups?


Mine also has a CLK hookup I am not sure of.


WIll they run with step and dirrection and enable from Mach3?


I do know they have a lot more power than you would expect. I checked them ouot while they was on the copier. I have one much bigger that really had a lot of power.


IDK if they would be strong enough to run a table as big as you are wanting though. They might with gearing and not expecting to much speed. Be great for something like a Taig mill with ballscrews though.



Jess

[myxo]

thanks for the clarification.
I tried reading up on BLDC, but I am left more confused.
According to wikipedia "BLDC motors are a popular motor choice for model aircraft including helicopters...favorable power to weight ratios"
"The large power to weight ratio of modern batteries and brushless motors allows models to ascend vertically, rather than climb gradually"
and
"Their popularity has also risen in the Radio Controlled Car, Buggy, and Truck scene, where sensor-type motors (with an extra six wires, connected to Hall effect sensors) allow the position of the rotor magnet to be detected. "

That makes this seem like a powerful motor... So can this be used as a stepper? If it would work on something like a TAIG min mill that would be great.

i am quite clueless when it comes to motors and such.
Is PS = power supply?
What is LD and CLK?

[LUCKY13]

Thats what I was asking, what is the PS, LD connnections on your motors? Mine has these, but also has a CLK connection ( WHat is CLK connection, anyone).

I don thtink PS is power supply unless its like a logic power feed. The 24v and PGND are the power supply connections for the motor itself. But something has to control the chip and IDK if there is power regulated down from the 24v supply or it needs a different supply for the chip.

I am not good enough to read the data sheet to the chip and know what it needs. Mine also has a different chip than yours. It uses the SLA6023 to drive the motor but then its got a nother chip for control but the numbers are not there ( atlest this one motor i have in hand right now, I do have one just like yours).




The motors cant be run as steppers. There totally different designs. They may have enough power to run a bigger machine than I am thnking but they will run something like a Taig very easy. They are very strong. They can take the place of a stepper, but what type of signal they need to be driven is the question (step/dirrection, PWM, quanature or analog or what ever). Thats where we need to know what is the PS and LD, and in my case also the CLK termanals. If we new that then using them would no problem as long as they will drive from step and dirrection. I think EMC2 will drive with one of the other possible ways but Mach we need them to be the step adn dirrection inputs.


Maybe someone will drop in and help us here. I am sure there have been some others that have had there hands on these motors. I think I have about 10 of them so it would be good for me to be able to use them even if its just for simple stuff.

BTW, all the electronics could be bypassed and a external BLDC drive used to drive them. But those drives are expencieve. All though a cheap drive may be able to be built if a diagram was out there somewhere.

Jess

[LUCKY13]

Can anyone help us with the hookup of these motors? What drives them and what the pin labling is. The high voltage side is a no brainer. It would be helpfull if we could get these motors going.


Jess

[garym1957]

Hey there.
I'm afraid those little motors wont have the umph to deliver any cutting pressure. They will be working very hard as is, trying to overcome their own inertia, with a little force left over to turn whatever gizmo they were designed to turn. 24 Volts is kinda balsy for these little motors, but what feels like really strong holding torque can quickly drop as RPMS increase.

The printer's steppers often come attached to a circuit board. Depending on the machine, that could be the driver(probably) or a positional encoder(also likely) ... Have you tried applying voltage and trying to "operate" the motor with 5Volt signals thru a 330 ohm resister? Some signal inputs are visible on the board.

Don't be discouraged. Using 1/4-20 threaded rod and maybe some fuel line for shaft to screw couplings, you can build a simple machine to demonstrate the physics of the system you have in mind. Great experimentation and excellent proof of concept. Only, no real cutting except MAYBE for balsa or thin foam. You could definitely make a cool little pen-plotter. (Use a solenoid for the Z)

There my 2 cents. Hope it helps.

[packrat]

The BLDC motors are an offshoot of the stepper motor. In steppers, most have 200 steps per revolution. The BLDC have only 12 or 16 steps per revolution.

Because of the lower number of steps the BLDC is used normally for continuous rotation, like in models for propulsion. In the printers they are used to feed the paper.

[myxo]

Thanks guys for the explanation.
I guess with the lower steps and lack of torque, these are probably only good for maybe designing and learning how to set things up as far as cnc (routing) is concerned.

[James Newton]

If you are looking for good stepper motors from discarded office equipment, there is a list at:

techref.massmind.org/techref/io/stepper/linistep/motors.htm

Check the notes in the far right had side. There are some very nice motors out there if you can find the right equipment.

And if you know of a good motor to be found in something, please use the form under the list to add that info? Thanks!