Enhanced ambient temperature detection
Methods, systems, and apparatus, including computer programs encoded on computer-storage media, for a device with improved ambient temperature detection. In some implementations, a device includes a housing that forms an interior space, and the housing includes an exterior surface, a pass-through region that defines a through-hole between the interior space to the exterior surface, and a recess at the exterior surface adjacent to the pass-through hole. The device includes a printed circuit board disposed within the interior space of the plastic housing. The device includes a flexible printed circuit substrate including a first end region that is connected to the printed circuit board that is disposed within the interior space of the housing, a second end region at an opposite end of the flexible printed circuit substrate than the first end region, that is disposed in the recess at the exterior surface of the housing, and a middle region that passes through the through-hole between the first end region and the second end region. The device includes a temperature sensor disposed at the second end region of the flexible printed circuit substrate in the recess at the exterior surface of the housing. The device includes a protective layer that is disposed on at least a portion of the exterior surface of the housing and that covers the recess and the through-hole.
1. A device comprising:
a housing that forms an interior space, and that includes (i) an exterior surface, (ii) a pass-through region that defines a through-hole between the interior space to the exterior surface, and (iii) a recess at the exterior surface adjacent to the through-hole;
a printed circuit board disposed within the interior space of the housing;
a flexible printed circuit substrate including (i) a first end region that is connected to the printed circuit board that is disposed within the interior space of the housing, (ii) a second end region at an opposite end of the flexible printed circuit substrate than the first end region, that is disposed in the recess at the exterior surface of the housing, and (iii) a middle region that passes through the through-hole between the first end region and the second end region;
a temperature sensor disposed at the second end region of the flexible printed circuit substrate in the recess at the exterior surface of the housing; and
a protective layer that is disposed on at least a portion of the exterior surface of the housing and that covers the recess and the through-hole, wherein the protective layer comprises a sticker, comprises epoxy, or is formed from a metallized polymer, or is formed from a metal.
2. The device of claim 1 , wherein:
the temperature sensor is disposed on a first side of the flexible printed circuit; and
the first side of the flexible printed circuit faces the protective layer.
3. The device of claim 1 , wherein the temperature sensor is in contact with the protective layer.
4. The device of claim 1 , wherein the recess at the exterior surface of the housing has a deeper section between two higher sections.
5. The device of claim 4 , wherein:
a first higher section of the two higher sections of the recess is positioned adjacent to the through-hole;
a second higher section of the two higher sections of the recess is positioned away from the through-hole; and
a portion of the second end region of the flexible printed circuit substrate is secured to the second higher section of the two higher sections of the recess.
6. The device of claim 4 , wherein the temperature sensor is disposed at the second end region of the flexible printed circuit substrate in the deeper section of the recess at the exterior surface of the housing.
7. The device of claim 4 , wherein the temperature sensor is disposed on a first side of the flexible printed circuit at the second end region of the flexible printed circuit substrate above the deeper section of the recess at the exterior surface of the housing.
8. The device of claim 7 , wherein a gap is formed between a second side of the flexible printed circuit at the second end region of the flexible printed circuit substrate and the deeper section of the recess at the exterior surface of the housing.
9. The device of claim 1 , wherein the recess at the exterior surface of the housing has a width that is slightly wider than the width of the second end region of the flexible printed circuit substrate and a length that is slightly longer than the length of the second end region of the flexible printed circuit substrate.
10. The device of claim 1 , wherein the pass-through region of the housing defines the through-hole such that the through-hole is substantially perpendicular with respect to the protective layer.
11. The device of claim 1 , wherein the protective layer is formed from a polymer.
12. The device of claim 11 , wherein the polymer is biaxially-oriented polyethylene terephthalate.
13. The device of claim 1 , wherein the metalized polymer is biaxially-oriented polyethylene terephthalate having a deposit layer of metal thereon.
14. The device of claim 1 , wherein the protective layer is secured to the at least portion of the exterior surface of the housing through an adhesive.
15. The device of claim 1 , wherein:
the housing contains an upper housing unit having a top exterior surface and a lower housing unit;
the top housing unit is secured to the lower housing unit; and
the protective layer is disposed on at least a portion of the top exterior surface.
16. A method comprising:
placing a printed circuit board within an interior space of a housing that includes (i) an exterior surface, (ii) a pass-through region that defines a through-hole between the interior space to the exterior surface, and (iii) a recess at the exterior surface adjacent to the through-hole;
placing (i) a first end region of a flexible printed circuit substrate within the interior space of the housing, (ii) a second end region of the flexible printed circuit substrate at an opposite end of the flexible printed circuit substrate than the first end region and in the recess at the exterior surface of the housing, and (iii) a middle region of the flexible printed circuit substrate through the through-hole between the first end region and the second end region;
placing a temperature sensor at the second end region of the flexible printed circuit substrate in the recess at the exterior surface of the housing;
securing the first end region of the flexible printed circuit substrate to the printed circuit board; and
covering the recess and the through-hole with a protective layer, wherein the protective layer comprises a sticker, comprises epoxy, or is formed from a metallized polymer, or is formed from a metal.