The
notched metal edge of the program disk has perforations or
grooves made to hold the pins which are placed in a series
to form the program or pattern for ringing the bells.
The
program disk's front face had figures from 1 to 12 to
resemble a clock dial. The clock dial was divided into 5
minute intervals. (Some of the Frick clocks were marked in
two and one-half minute intervals). Perforations in the
outer metal portion of the program dial held the pins which
were inserted at the place on the dial which corresponded to
the time when bells were to ring. The program disk made one
revolution every twelve hours.
The
free ends of the contact arms were bent laterally so they
would come in contact with the pins placed into the notched
area of the program disk when the ends of the contact arms
were raised. This happened when the bend or
"shoulder" engaged with the pins located in the
revolvable drum. When the contact arm and a pin from the
program disk engaged, the electric circuit was closed and
the bell would ring. A post of insulated material along with
socketed holders helped to keep the contact pins held in
place.
The
revolvable drum sits behind the contact pins near where the
bend or "shoulder" of the contact arms are
attached.
The
spring motor which powers the rotation of the program disk.
The motor is set in motion automatically every 5 minutes and
moves the disk an equivalent space.
