Brake sticking on Feed Table Hoist

Does anyone have any information on how to properly adjust the brake on the Feeder Pile Hoist Motor on a Komori NL 528. Ours is sticking and we cannot get it adjusted correctly.

 

Brake should be ON/OFF and nothing more

As far as i know (and i do not know your brake or it's history) it is very basic , and the device is pre-adgested.
Will it keep the motor in braked condition and not release it or will it not brake the motor (so it slips down and fail to climb up ) ???

Do you wish to change the speed the table moves up ?

Meny

 

The table will only move in auto. It won't move up or down in manual

 

what is the logic then ?

If the brake is working in AUTO and not working at all in manual why do you think the problem is in the brake ???
If the brake stops the table from slipping down when fully loaded and releases the table to go up in auto mode , then nothing wrong with the brake !

Plain logic....

 

you may have a PLC issue
Tye brake is a mechanical device with 2 ways - open / closed
if it is OK in auto mode , it can not be wrong mechanically

So the problem may be in the PLC controling it (bad diode on board ?)
If i remember right , you should have (in the original PLC) 2 diodes that are not in use.
If it is the diode , you can use one of them for a faster respons , but this is for an electric engineer who knows what he is doing to check....

can't answer this in remote

Good luck
Meny

 

I agree with Meny on the brake, if the feeder pile works properly in Auto, the brake is probably not your problem. The key word here is properly! How many impressions do you have? Has the brake ever been adjusted? If the press is several years old and you have not adjusted the brake, it may be time to do so. Most of the newer Komori's brakes are spring loaded and you merely tighten the 3 crush nuts (metal version of nylock) 1-2 faces evenly. The exact gap should be in your manual but I'd guess around 0.2-0.3mm.

As for PLC failure, not likely. Almost all of the feeder pile circuitry on your press is relay logic, limit switches and sensors. Do the contactors pull in when you push the up/down button? Does the motor get hot?

 

The brake was the problem. Replaced it and it works just fine. Thanks for the help

 

An important yet often overlooked element of the hoist brake circuit is the brake capacitor. As the brake disc wears, the distance between the pressure plate and magnet increases to the point that the magnetic field can no longer overcome the force of the springs pressing the pressure plate to the disc. A deteriorated capacitor can accentuate this problem because it no longer provides the initial electrical 'kick' to pull the pressure plate from the disc.

Adjusting or replacing the brake will temporarily correct the problem but if the capacitor is failing, the problem will soon return as the disc begins to wear and the capacitor deteriorates further. Replacing the capacitor is an inexpensive preventive measure.

Visual signs of a failing capacitor are the presence of leaking electrolyte or swelling of the capacitor.

 

I have one new - old stock JPE MSB-140 feeder hoist motor brake for Komori or Mitsubishi 40 inch press left in my inventory. Asking price is just over half the list price. Includes capacitor and warranty.
ah6k@warwick.net