Patent ID: 11972081
Assignee: NISSHA CO., LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 0:
1. A capacitive pressure sensor, comprising:
a first electrode sheet in which a first electrode layer is formed on a first insulating sheet;
a second electrode sheet in which a second electrode layer is formed on a second insulating sheet;
an elastic body layer formed by a foam sheet in which air bubbles having an average air bubble diameter of 2 to 40 μm are dispersed and sandwiched between the first electrode sheet and the second electrode sheet; and
adhesive layers, one of the adhesive layers being formed on a surface of the elastic body layer on a side of the first electrode sheet and another of the adhesive layers being formed on a surface of the elastic body layer on a side of the second electrode sheet, wherein
when the first electrode sheet or the second electrode sheet is pressed, the capacitive pressure sensor detects a pressing force based on a capacitance change between the first electrode layer and the second electrode layer according to a distance change between the first electrode layer and the second electrode layer, and, wherein
Vg/(Vp+Vg) in a surface layer region at a depth of 20 μm from a surface of the foam sheet is smaller than a half of Vg/(Vp+Vg) in an inner region deeper than the surface layer region of the foam sheet, wherein
Vg refers to a volume of gases in the air bubbles contained per unit volume, and
Vp refers to a volume of plastic contained per unit volume in a portion where the air bubbles are absent.