ATO question about switch contact on ATO

[focusrsh_b07732]

I have what I think is an ATO. I have a question about the switching contact in the "ecapement".

There is an arched arm that rocks. On the end of the arm is a pin that contacts and lifts two brass leaf-springs, In the photo here, the pin is labeled "1". The leaf springs are connected to the -side of the battery through a wire. When the pin touches the springs it briefly completes the circuit to the coil through the clock frame.

However, there is also a brass arm, labeled (2) in the photo, that the springs rest against (or so I think) when they are not lifted. When they touch this arm the circuit is also completed.
OK, so I'm confused. It the pin the switch contact? Or should the pin be coated (insulated) so it is isolated from the brass springs , and thus its only purpose is to lift the two springs aways from the #2 arm and break the circuit.

 

[praezis]

Contact is completed by the (platinum-) pin.
Contact leaves and their frame must be isolated from the clock plate.

Frank

 

[focusrsh_b07732]

Contact is completed by the (platinum-) pin.
Contact leaves and their frame must be isolated from the clock plate.

Frank

Thank you! I'll verify that the leaves are indeed isolatedfrom the clock plate.

 

[whatgoesaround]

The pin should just touch the contacts as it "jumps" out and not rest on them. The lower screws, fourth one up on your picture, will allow for adjustment.

 

[focusrsh_b07732]

Thank you for clarifying this.

 

[Dave T]

My ONE and only experience on one of these, indicates that the contact should be very light. I adjusted until there was no contact, and then engaged it back just enough!

(For whatever that information is worth.)

 

[focusrsh_b07732]

I posted the initial question and want to correct something. I said that the brass arm, #2 in the photo. completes the circuit when the flexible contacts touch it. NOT TRUE! It is isolated from clock frame along with the flexible contacts. It has nothing to do with the circuit except to adjust the contact gap.