Two-terminal temperature sensor with electrically isolated housing
View Patent ↗A two-terminal temperature sensor connects a first end of thermistor or other thermometer device to a first electrical terminal via an inner compression coil. A second electrical terminal is connected to a second end of the thermistor via an outer compression coil and a formed conductor. The inner compression coil and thermistor are positioned within the formed conductor. The inner compression coil and thermistor are prevented from contact with the formed conductor by an inner insulating tube. The first and second electrical contacts are mounted in a molded terminal assembly that insulates the electrical contacts from one another. The entire assembly is housed within a housing that is electrically isolated from the formed conductor and outer compression coil via an outer insulating tube and an insulating disk.
1. A two-terminal temperature sensor comprising
a housing having a sidewall, a closed bottom, and an open top;
an electrically conductive formed conductor housed within and electrically isolated from the housing and having a sidewall, an open top, and a closed bottom;
a thermometer device configured for placement within the formed conductor and in electrical contact with the closed bottom of the formed conductor;
an electrically conductive first terminal positioned within the open top of the housing;
an electrically conductive second terminal positioned within the open top of the housing and configured to be in electrical connection with the open top of the formed conductor; and
an electrically conductive first compression coil placed within and electrically isolated from the formed conductor and positioned between and electrically connecting the first terminal and a top of the thermometer device.
2. The two-terminal temperature sensor of claim 1 further comprising an electrically conductive second compression coil placed within the housing between and electrically connecting the second terminal and the open top of the formed conductor.
3. The two-terminal temperature sensor of claim 1 further comprising
an electrically non-conductive first insulating tube configured for placement between the formed conductor and both the first terminal and the thermometer device; and
an electrically non-conductive second insulating tube configured for placement between the housing and both the second terminal and the formed conductor.
4. The two-terminal temperature sensor of claim 1 further comprising a thin, electrically non-conductive, thermally conductive disk placed between the closed bottom of the housing and the closed bottom of the formed conductor.
5. The two-terminal temperature sensor of claim 1 further comprising
a terminal assembly fixed in the open top of the housing comprising
the first terminal;
the second terminal, wherein each of the first terminal and the second terminal define respective body portions and external protrusion portions; and
an electrically non-conductive terminal insulator, wherein
the body portions are enveloped by the terminal insulator and the external protrusion portions protrude from a top end of the terminal insulator.
6. The two-terminal temperature sensor of claim 5 further comprising a terminal divider configured to protrude from the top end of the terminal insulator between the external protrusion portions of each of the first terminal and the second terminal.
7. The two-terminal temperature sensor of claim 5 , wherein
the terminal insulator defines an annular groove in a sidewall; and
the housing is crimped around the annular groove in the terminal insulator.
8. The two-terminal temperature sensor of claim 5 further comprising an electrically non-conductive sealing washer configured to seal an interface between the terminal assembly and the housing from exterior contaminants.
9. The two-terminal temperature sensor of claim 5 , wherein the terminal assembly further comprises an electrical connector interfaced with the external protrusion portions of the first terminal and the second terminal.
10. The two-terminal temperature sensor of claim 9 , wherein the electrical connector is a Packard connector.
11. The two-terminal temperature sensor of claim 9 , wherein the electrical connector is a screw connector.
12. The two-terminal temperature sensor of claim 1 , wherein the thermometer device is a thermistor.
13. The two-terminal temperature sensor of claim 1 , wherein an exterior surface of the sidewall of the housing is threaded for screwing into an aperture in a device to be measured.
14. The two-terminal temperature sensor of claim 1 , wherein the housing is electrically non-conductive and thermally conductive.
15. A two-terminal temperature sensor comprising
a housing having a sidewall, a closed bottom, and an open top;
an electrically conductive formed conductor housed within the housing and having a sidewall, an open top, and a closed bottom;
a thermometer device configured for placement within the formed conductor and in electrical contact with the closed bottom of the formed conductor;
an electrically conductive first terminal positioned within the open top of the housing and configured to be in electrical connection with a top of the thermometer device;
an electrically conductive second terminal positioned within the open top of the housing and configured be in electrical connection with the open top of the formed conductor;
an electrically non-conductive first insulating tube configured for placement between the formed conductor and both the first terminal and the thermometer device; and
an electrically non-conductive second insulating tube configured for placement between the housing and both the second terminal and the formed conductor.
16. The two-terminal temperature sensor of claim 15 further comprising a thin, electrically non-conductive, thermally conductive disk placed between the closed bottom of the housing and the closed bottom of the formed conductor.
17. The two-terminal temperature sensor of claim 15 further comprising
a terminal assembly fixed in the open top of the housing comprising
the first terminal;
the second terminal, wherein each of the first terminal and the second terminal define respective body portions and external protrusion portions;
an electrically non-conductive terminal insulator, wherein
the body portions are enveloped by the terminal insulator and the external protrusion portions protrude from a top end of the terminal insulator.
18. The two-terminal temperature sensor of claim 17 further comprising a terminal divider configured to protrude from a top end of the terminal insulator between a first terminal protrusion of the first terminal and a second terminal protrusion of the second terminal.
19. A two-terminal temperature sensor comprising
a housing having a sidewall, a closed bottom, and an open top;
a terminal assembly fixed within the open top of the housing comprising
an electrically conductive first terminal;
an electrically conductive second terminal, wherein each of the first terminal and the second terminal define respective body portions, external protrusion portions, and internal contact portions; and
an electrically non-conductive terminal insulator, wherein
the body portions are enveloped by the terminal insulator, the external protrusion portions protrude from a top end of the terminal insulator, and the internal contact portions protrude from a bottom end of the terminal insulator within the housing;
an electrically conductive formed conductor housed within the housing and having a sidewall, an open top, and a closed bottom;
a thermistor configured for placement within the formed conductor and in electrical contact with the closed bottom of the formed conductor;
a thin, electrically non-conductive, thermally conductive disk placed between the closed bottom of the housing and the closed bottom of the formed conductor;
an electrically conductive first compression coil placed within the formed conductor and positioned between and electrically connecting the internal contact portion of the first terminal and a top of the thermistor;
an electrically non-conductive first insulating tube surrounding the first compression coil and interposed between the formed conductor and both the first compression coil and the thermistor;
an electrically conductive second compression coil placed within the housing between and electrically connecting the open top of the formed conductor and the internal contact portion of the second terminal; and
an electrically non-conductive second insulating tube surrounding the second compression coil and the formed conductor and interposed between the housing and both the second compression coil and the formed conductor.
20. The two-terminal temperature sensor of claim 19 , wherein
the terminal insulator defines an annular groove in a sidewall; and
the housing is crimped around the annular groove in the terminal insulator.