Fire Warden: What Is This???

[blackstone]

For years, I have been trying to find out what exactly this is. Some type of fire alarm, I would assume.

When the knurled knob is moved by hand, a loud metallic noise is produced. This must the alarming noise. There is a hanger on top, suggesting a permanent installation hanging from a ceiling. I just don't know how this alarm would be activated by a fire.

Any fire alarm experts around here?

Thanks,
Fred

 

[eronie]

Is there a keyhole on the back to wind it up?
Any type of fasteners holding if it together?

 

[blackstone]

Can't take it apart without destroying the covers.

Nothing to wind up anything. Turning the knurled knob in one direction makes the noise; turning in the other direction just rotates continually.

 

[cuffs054]

Maybe used flow of sprinkler system to drive bell?

 

[joe_in_philly]

Perhaps it is a manual fire alarm bell?

http://https//youtu.be/clhiwvjU8uI

 

[askolover]

Joe I saw that same video and wondered the same thing.

 

[thomasortega]

If that's true, this is the silliest fire alarm I've ever seen.

 

[eronie]

Maybe the knurled wheel rubs on the tire of the fire truck????

 

[johnb300m]

That's a toughy.
I tried searching for wind up alarms.
Google reverse image search.
Brand name search.
Nothing.
It also looks nothing like the plethora of old wind up fire alarms I found.

Maybe the best guess so far is that this was pressed up against a wheel of a fire truck to make the bell noise as they drove?

I got nothin' else.

 

[swestoyz]

Looks like a mechanical heat sensing fire alarm. Several years ago I was in a house filled with alarms similar to these, and the owner was quite proud of them. Probably safe to use a conventional smoke detector within the same location and not solely rely on the heat alarm.

Ben

https://www.nachi.org/forum/f19/smoke-alarm-hubcap-ufo-548/

 

[blackstone]

Ben,

You have provided the best lead so far. I read the forum in your link. What is described there is a heat-sensitive, wind-up alarm, much more modern than what I have.

When I rotate the knob on my alarm, it does not appear to come to a stop (i.e., fully wound); unless I gave up too soon. I don't see any kind of tab, as described in the forum, that would activate the alarm. Perhaps my alarms are single-use. Now I am curious to actually remove the cover, even if it means being unable to replace it.

Thanks for the lead.

 

[blackstone]

I took it apart

Apparently, it is a one-time use, heat-sensitive fire alarm. The copper strap must be wound up, and released when a source of heat melts a tab of some sort.

Sounds rather primitive; it would only work if it were placed above a fire producing a lot of heat, and the alarm would sound only until the strap unwound completely. So, you would have to be close enough to the alarm (which would have to be close enough to the fire) in order to hear the sound for a short time. And if the alarm is to serve its purpose, you would have to be unaware of the probably-intense heat.

 

[circlew]

If the fusible metal part is like that of a sprinkler head, it would melt and activate the alarm before the temperature got too high. An "ordinary" rated fire sprinkler will activate when the surrounding temperature reaches 155F for a short time. If this alarm was ceiling mounted, it wouldn't take much of a fire to set it off.