Force sensor mount and related housings and systems that incorporate the same
Assemblies include a chassis having a first side configured to receive a force-sensitive surface, a support structure including first electrode portions, and resilient mounting elements attached to the chassis and to the support structure. The mounting elements include second electrode portions positioned adjacent to the first electrode portions. Force-sensitive systems include force sensors including portions of a support structure and portions of a mounting element that are adapted to relatively move responsive to one or more applied forces, and a controller configured to identify the one or more applied forces by determining movement between the support structure and the mounting element. Methods include detecting changes in capacitances of respective capacitors formed by first electrode portions on a support structure and second electrode portions defined by mounting elements coupling a chassis to the support structure. Force values and force locations are determined from the detected changes in capacitances.
1. An assembly, comprising:
a chassis comprising a first side configured to receive a force-sensitive surface;
a support structure including first electrode portions; and
resilient mounting elements attached to the chassis and to the support structure, the resilient mounting elements positioned to allow relative movement between the chassis and the support structure, wherein the resilient mounting elements comprise second electrode portions, the second electrode portions positioned adjacent to the first electrode portions.
2. The assembly of claim 1 , wherein the resilient mounting elements comprise four strip springs respectively positioned near corners of the chassis.
3. The assembly of claim 2 , wherein the strip springs are oriented at an angle of about 45 degrees from a peripheral edge of the chassis.
4. The assembly of claim 1 , wherein the resilient mounting elements consist essentially of a metal material.
5. The assembly of claim 1 , wherein a gap is defined between each adjacent first electrode portion and second electrode portion when no external force is applied to the force-sensitive surface.
6. The assembly of claim 5 , further comprising biasing elements that, while a force is not applied to the first side of the chassis, are adapted to maintain the gaps defined between each adjacent first electrode portion and second electrode portion.
7. The assembly of claim 6 , wherein the gaps comprise air gaps.
8. The assembly of claim 6 , wherein a material is disposed in the gaps.
9. The assembly of claim 1 , wherein the resilient mounting elements are positioned to allow relative movement between each adjacent first electrode portion and second electrode portion.
10. The assembly of claim 1 , wherein an end portion of each of the resilient mounting elements is configured as a mounting point of the support structure to the chassis.
11. The assembly of claim 1 , wherein the support structure comprises a printed circuit board (PCB).
12. A method of estimating a force applied to a force-sensitive surface, the method comprising:
detecting changes in capacitances of respective capacitors formed by first electrode portions on a support structure and second electrode portions defined by mounting elements, the mounting elements coupling a chassis receiving a force-sensitive surface to the support structure;
using the detected changes in capacitances to determine a force value of a force applied to the force-sensitive surface; and
comparing the changes in capacitances of the respective capacitors to estimate a location of the force applied to the force-sensitive surface.
13. A force-sensitive system, comprising:
a chassis having a first side;
force sensors comprising portions of a support structure and portions of a mounting element, the portions of the support structure and the portions of the mounting element adapted to move closer and/or apart responsive to one or more forces applied to the first side; and
a controller supported by the support structure and configured to identify the one or more forces applied to the first side by determining movement between the portions of the support structure and the portions of the mounting element.
14. The force-sensitive system of claim 13 , wherein the controller is configured to detect capacitance changes of respective capacitors formed between the portions of the support structure and the portions of the mounting element upon movement of the mounting element relative to the support structure.
15. The force-sensitive system of claim 14 , wherein the controller is further configured to estimate a location of the one or more forces applied to the first side by comparing the detected capacitance changes of the respective capacitors.
16. The force-sensitive system of claim 13 , wherein the first side comprises a liquid crystal display touchscreen.
17. The force-sensitive system of claim 13 , further comprising at least one spacer positioned between the mounting element and the support structure to define an initial space between the portions of the mounting element and the portions of the support structure when the one or more forces is not applied to the first side.
18. The force-sensitive system of claim 13 , further comprising at least one biasing element positioned between the chassis and the support structure to bias the chassis to an initial position relative to the support structure when the one or more forces is not applied to the first side.
19. The force-sensitive system of claim 13 , further comprising insulators positioned between the portions of the mounting element and the portions of the support structure.
20. The force-sensitive system of claim 13 , wherein the mounting element comprises strip springs that are respectively attached to the support structure with at least one electrically conductive fastener.
21. The force-sensitive system of claim 13 , further comprising a protrusion between the chassis and the support structure, the protrusion configured to abut against a surface to limit relative movement between the chassis and the support structure when the one or more forces is of a sufficient value is applied to the first side.
22. A system, comprising:
a force-sensitive surface;
a controller coupled to the force-sensitive surface; and
a mounting assembly, the mounting assembly comprising:
a chassis comprising a first side configured to receive the force-sensitive surface;
a support structure including first electrode portions; and
resilient mounting elements attached to the chassis and to the support structure, the resilient mounting elements positioned to allow relative movement between the chassis and the support structure, wherein the resilient mounting elements comprise second electrode portions, the second electrode portions positioned adjacent to the first electrode portions.
23. The system of claim 22 , wherein the force-sensitive device is configured to produce a force result responsive to an object touch at the surface.
24. The system of claim 23 , wherein the controller is configured to determine a force measurement responsive to the force result.
25. The system of claim 23 , wherein the controller is configured to determine a location at the surface responsive to the force result.
26. The system of claim 22 , further comprising a touch-sensitive device configured to produce a sense result responsive to an object touch at the surface or an object in close proximity to the surface.
27. The system of claim 22 , wherein the surface is selected from a group comprising: a touchscreen, a touchpad, a back plate, and a side of a housing.