Height sensor and air spring apparatus incorporating the same in the air chamber

A height sensor for measuring the change in height between two surfaces, comprising:

• a sensing element being mounted to one of a first surface and a second surface, said surfaces separated by a first height;
• an indicating element having a first portion connected to said first surface, a second portion connected to said second surface, and an elastic member connected therebetween and having a range of lengths;
• each said length of said elastic member defining a different indicating level sensible by said sensing element;
• wherein a change in height of said first surface relative to said second surface produces a proportional change of said indicating level relative to said sensing element;
• and
• wherein said indicating element further comprises:
• a reservoir member constituting said first portion of said indicating element connected to said first surface;
• said reservoir member having a top wall, a side wall, and a bottom wall defining a measurement cavity therewithin and moving with said first surface;
• said bottom wall having a passage formed therethrough;
• an elastic tube member constituting said elastic member of said indicating element;
• said tube member having an upper end, a lower end, and an inner diameter defining a tube cavity therewithin and having a tube capacity;
• said upper end of said tube member being connected to said bottom wall of said reservoir member at said passage to form a fluid connection between said reservoir member and said tube member;
• said lower end of said tube member being connected to said second portion of said indicating element to move with said second surface;
• and
• a fluid material disposed within said measurement cavity and said tube cavity and having a free surface within said reservoir member defining said indicating level;
• wherein, upon movement of said upper end of said tube member relative to said lower end of said tube member, the tube capacity changes to exchange said fluid material between said reservoir member and said tube member to move the position of said indicating level within said reservoir member in proportion to movement of said first surface relative to said second surface.

A height sensor for measuring the change in height between two surfaces, comprising:

• a sensing element being mounted to one of a first surface and a second surface, said surfaces separated by a first height;
• an indicating element having a first portion connected to said first surface, a second portion connected to said second surface, and an elastic member connected therebetween and having a range of lengths;
• each said length of said elastic member defining a different indicating level sensible by said sensing element;
• wherein a change in height of said first surface relative to said second surface produces a proportional change of said indicating level relative to said sensing element;
• and
• wherein said elastic member of said indicating element further comprises an upper spring member, a lower spring member, and a pointer member;
• said upper spring member being connected between said first portion of said indicating element and said pointer member;
• said upper spring member having a first free length and a first spring constant;
• said pointer member being connected between said upper spring member and said lower spring member and defining an indicating level;
• said lower spring member being connected between said pointer member and said second portion of said indicating element;
• said lower spring member having a second free length and a second spring constant;
• said first and second free lengths and said first and second spring constants adapted to position said pointer member adjacent said sensing element;
• wherein, upon movement of said first portion of said indicator member relative to said second portion of said indicator member, the position of said pointer member changes relative to said sensing element in proportion to movement of said first surface relative to said second surface.