[Noisebridge-discuss] Elevator repair

[lee worden]

If you're going to work on the elevator, be sure to do the background 
reading:

http://en.wikipedia.org/wiki/The_Intuitionist


> Date: Tue, 1 Feb 2011 06:12:06 -0800 (PST)
> From: Jake <jake at spaz.org>
> To: noisebridge-discuss at lists.noisebridge.net
> Subject: Re: [Noisebridge-discuss] Elevator repair
> 
> Okay so Monday night, Rachel and I climbed through the hatch in the cieling 
> of the elevator, just like in the movies, and stood on top of the thing to 
> figure out why it doesn't let itself be called when it's there.
>
> I was right that there is a switch activated when the elevator is at the top 
> of its travel, but that's like a foot higher than our floor and is not being 
> triggered.  The button that is being triggered is the same kind however, and 
> is in a metal junction box and its arm has a roller bearing on it and is very 
> serious like you would expect.
>
> http://spaz.org/~jake/pix/elevator.jpg
>
> My theory now is that inside that junction box is either one Dual-Pole 
> microswitch (two sets of contacts) or two separate microswitches, and one of 
> them is failing intermittently.
>
> One of them makes the elevator stop at our floor, and is working.  The other 
> tells the system the elevator has arrived and is ready to go and is not 
> making contact all the time.  Apparently this also happens on the second 
> floor.
>
> I say the solution is to open either the safety switchbox above and examine 
> the microswitches inside, and order two or three of them, or do the same to 
> the actual switchbox that stops our elevator which presumably has the same 
> switches in it anyway.
>
> When we open the switchbox below it, whether to examine it or to put in the 
> new switches (buttons technically) we will do so by moving the elevator down 
> from our floor, hit STOP after a couple of feet, and then climb out the 
> ceiling hole to access the switchbox of our floor by standing on top of the 
> elevator again.  Because we can't access the switchbox while the elevator is 
> properly stopped on our floor.
>
> There is a mechanism to prevent opening the internal gate of the elevator 
> when not on a proper floor but it doesn't work, and if it did we could easily 
> bypass it by tugging a cable on top of the elevator while opening the gate, 
> so that elevator repairpersons could take a break and get a kombucha while 
> not finished fixing the elevator, while it's 2 feet low.
>
> Note that when i say switches, i am talking about momentary switches also 
> known as buttons, most likely "micro switches" made of Bakelite with a lever 
> arm and a clicky noise, but we won't know until we open one of the boxes.  I 
> should have done that Monday night (the topmost box) and taken pictures so 
> that someone could go to the elevator parts store.  Whatever.
>
> Someone should make an elevator repair wiki and put these posts on it.
>
> -jake
>
>> Wait you debugged the elevator?  Let's fix it then!  Having it actually
>> work properly would be the best solution.  I'll be happy to be the one
>> to Do it if you can show me this microswitch of which you speak.
>
> i am just mentally picturing the problem.  The elevator comes to our
> floor, which is the top floor, and there's a button "A" on the rail to
> keep it from going too far.  There is another button "B" which tells the
> system that it's on the third floor, and is ready to be called to another
> floor because it's done moving around.  The button "A" is being triggered
> before button "B" and the elevator stops moving before it really "arrives"
> at the third floor.
p>
> When one goes in there and presses the 3 button again, the button bypasses
> the stop switch for long enough to run the motor enough to bump it up a
> quarter-inch until it presses button "B" telling the system it's arrived
> at the third floor and everything is okay.
>
> It might not be as simple as adjustment however, because it could be that
> the capacitor or diode protecting the buttons' contacts from the inductive
> kick of the relay it triggers has failed to protect the button contacts,
> and the button needs to be replaced.  Only an elevator-repairfolk will
> have the exact correct replacement button, and really know how to adjust
> it.
>
> As much as I would be okay with getting covered in grease and mouse-shit
> trying to find both buttons and adjusting them, and hoping that the
> problem is only adjustment (which is slightly unlikely) i think it's
> probably better to have the repair made by the professional.  However if
> the landlord/property owner flat-out says that they'd rather us try to fix
> it first, we should go for it.
>
> But at this point, with the elevators' behavior properly sussed out (the
> note on the door is excellent) it should be easy for a repairperson to do
> the job without wasting too much time.
>
> -jake
>
>
>