 |
Cryovac test chamber on the bench in the lab. The chamber began
its life (before it knew us) as a pressure cooker, including having
6 "dogs" with screws to hold the cover on under pressure.
We modified it by adding the "stovepipe" at the back that
supported the CTI 1050 cold head. Inside the test chamber, the first
cold station (50 K) was bolted to a modified aluminum pot (from Ace
Hardware, I believe). This was surrounded by a floating, highly polished
aluminum cold shield - held off from the active cold pot by small
G10 threaded stubs. Wiring passed through a hermetic connector on
the backside. |
 |
Temperature monitoring and control were provided by a Lakeshore
LS218, a Lakeshore LS 331, and a pair of Chromolux PID controllers.
Thermocouple vacuum monitoring unit is just under the Chromolux pair. |
 |
The stepper motor test plate and anodization test plate (with heater)
were placed on G10 standoffs inside the active cold volume. A strap
from the CTI 1050 cold head's second stage (10 K) went to the heater
block and another went from the heater block to the motor plate. In
this fashion, we were able to bring the motors to fixed, stable temperatures
anywhere from 27 to 300 K. Before testing, covers were put in place
and the entire volume vacuum pumped. |
|