Mechanical vibration switch

1. A mechanical vibration switch, comprising:

a bar pivotally attached to a reference structure;

a magnet disposed on the bar, the magnet having a first surface with a first surface area;

an inertial mass attached to the bar;

a magnetic material part disposed in spaced apart relation to the magnet such that a magnetic force acts on the bar in a first direction, the magnetic material part having a second surface, the second surface having a second surface area, the second surface facing the first surface of the magnet when the bar contacts a stop;

an electrical switch coupled to the bar such that the state of the switch changes from open to closed depending on the position of the bar;

a spring acting on the bar to provide a force in a second direction opposite to the first direction;

wherein the magnetic material part is adjustable between a first position where a first portion of the surface area S of the second surface is disposed in facing relation with a corresponding surface area S of the first surface to a second position where a second portion of the surface area S of the second surface is disposed in facing relation with a corresponding surface area S of the first surface while the distance d between the first surface and the second surface remains substantially constant; and,

wherein the second portion of the surface area S of the second surface is larger than the first portion of the surface area S of the second surface.

2. The mechanical vibration switch of claim 1 , wherein the first surface of the magnet is curved.

3. The mechanical vibration switch of claim 1 , wherein the first surface of the magnet is spherical.

4. The mechanical vibration switch of claim 1 , wherein the electrical switch is a relay switch having a relay throw.

5. The mechanical vibration switch of claim 1 , wherein the magnetic material part is cylindrical.

6. The mechanical vibration switch of claim 5 , wherein the magnetic material part has a threaded portion.

7. The mechanical vibration switch of claim 1 , wherein the relation between the magnetic force and the amount of surface area S of the first and second surfaces that is disposed in facing relation is substantially linear.

8. The mechanical vibration switch of claim 1 , wherein the bar has a distal end and a proximal end.

9. The mechanical vibration switch of claim 1 , wherein the magnet is disposed at the distal end of the bar.

10. The mechanical vibration switch of claim 1 , wherein the bar is pivotally attached to a reference structure at the proximal end.

11. A mechanical vibration switch, comprising:

a bar pivotally attached to a reference structure;

one of a magnet and a magnetic material part disposed on the bar, the magnet having a first surface with a first surface area;

an inertial mass connected to the bar;

the other of the magnet and magnetic material part disposed in spaced apart relation to the one of a magnet and a magnetic material part such that a force acts on the bar in a first direction, the magnetic material part having a second surface, the second surface having a second surface area, the first and second surfaces facing each other when the bar engages with a stop;

an electrical switch coupled to the bar such that the state of the switch changes from open to closed depending on the position of the bar;

a spring acting on the bar to provide a force in a second direction opposite to the first direction;

wherein one of the magnet and magnetic material part is adjustable such that the amount of surface area S disposed in facing relation between the first surface and the second surface varies.

12. The mechanical vibration switch of claim 11 , wherein the first surface of the magnet is curved.

13. The mechanical vibration switch of claim 11 , wherein the first surface of the magnet is spherical.

14. The mechanical vibration switch of claim 11 , wherein the electrical switch is a relay switch having a relay throw.

15. The mechanical vibration switch of claim 11 , wherein the relation between the magnetic force and the amount of surface area S of the first and second surfaces that is disposed in facing relation is substantially linear.

16. The mechanical vibration switch of claim 11 , wherein the bar has a distal end and a proximal end.

17. The mechanical vibration switch of claim 11 , wherein one of the magnet and the magnetic material part is disposed at the distal end of the bar.

18. The mechanical vibration switch of claim 11 , wherein the bar is pivotally attached to a reference structure at the proximal end.

19. A mechanical vibration switch, comprising:

a bar having a distal end and a proximal end, the bar pivotally attached to a reference structure at the proximal end;

an inertial mass attached to the bar;

a magnet disposed at the distal end of the bar, the magnet having a first surface with a first surface area;

a magnetic material part disposed in spaced apart relation to the magnet such that a magnetic force acts on the bar in a first direction, the magnetic material part having a second surface with a second surface area, the second surface facing the first surface on the magnet when the bar contacts a stop;

means for changing the state of a switch from open to closed in response to the position of the bar;

means for biasing the bar in a second direction opposite the first direction; and,

means for advancing the magnetic material part such that the second surface moves parallel to the first surface of the magnet.

20. The mechanical vibration switch of claim 19 , wherein the relation between the magnetic force and the amount of surface area S of the first and second surfaces that is disposed in facing relation is substantially linear.