US 12,313,488 B2
Thermal insulation system for a capacitance diaphragm gauge
Matt E. Datlen, Carson City, NV (US); Kurt R. Rustin, San Diego, CA (US); Nathaniel S. Hankel, Lemon Grove, CA (US); and Shawn C. Brown, Menifee, CA (US)
Assigned to Sumitomo (SHI) Cryogenics of America, Inc., Allentown, PA (US)
Filed by Sumitomo (SHI) Cryogenics of America, Inc., Allentown, PA (US)
Filed on Nov. 29, 2022, as Appl. No. 18/059,845.
Claims priority of provisional application 63/285,774, filed on Dec. 3, 2021.
Prior Publication US 2023/0175907 A1, Jun. 8, 2023
Int. Cl. G01L 9/12 (2006.01); G01L 19/04 (2006.01)
CPC G01L 9/125 (2013.01) [G01L 19/04 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A thermally controlled capacitance diaphragm gauge (CDG) sensor comprising:
a CDG sensor; and
a thermal control system for the CDG sensor having at least a first sensor signal wire and having a gas inlet tube, the gas inlet tube having an outer surface, the thermal control system comprising:
a vacuum enclosure that includes a first end and a second end, the first end opening into a cavity in which the CDG sensor is mounted, the second end including a through bore passing into the cavity, the outer surface of the gas inlet tube hermetically sealed to the vacuum enclosure;
an end cap hermetically sealed to the first end of the vacuum enclosure to seal the cavity of the vacuum enclosure;
at least a first sensor signal connector passing through a first through bore of the end cap, the first sensor signal connector hermetically sealed to the end cap, the first sensor signal connector electrically connected to the first sensor signal wire;
an internal heater mounted to the CDG sensor within the vacuum enclosure, the internal heater having an internal heater cable;
a sensor heater connector passing through a second through bore of the end cap, the sensor heater connector hermetically sealed to the end cap, the sensor heater connector electrically connected to the internal heater cable;
an internal temperature sensor coupled to the CDG sensor, the internal temperature sensor having at least a first temperature sensor wire and a second temperature sensor wire;
at least a first temperature sensor connector electrically connected to the first temperature sensor wire and a second temperature sensor connector electrically connected to the second temperature sensor wire, the first temperature sensor connector passing through a third through bore of the end cap, the second temperature sensor connector passing through a fourth through bore of the end cap, the first and second temperature sensor connectors hermetically sealed to the end cap;
an evacuation tube passing through a fifth through bore of the end cap, the evacuation tube hermetically sealed to the end cap, the evacuation tube configured to enable gas to be removed from the cavity of the enclosure to form a vacuum insulator around the CDG sensor within the cavity; and
an ion gauge positioned in a through bore of the end cap, the ion gauge hermetically sealed to the end cap, the ion gauge configured to detect the presence of gas molecules within the cavity of the vacuum enclosure.