DEVICE FOR MECHANICAL WEIGHT BEARING INDICATION WITH LOAD RANGE CAPABILITY

• US 20080041169A1
• Filed: 08/18/2006
• Published: 02/21/2008
• Est. Priority Date: 08/18/2006
• Status: Active Grant

• Current Assignee: Rensselaer Polytechnic Institute
• Original Assignee: Rensselaer Polytechnic Institute
• Inventors: Walczyk, Daniel F., Bornhoft, Stephen
• Granted Patent: US 7,493,810 B2
• Time in Patent Office: Days
• US Class Current: 73/862.391
• CPC Class Codes: G01L 1/04 by measuring elastic deformation of gauges, e.g. of springs
• CPC Class Codes: G01L 5/06 using mechanical means G01L5/042, G01L5/045 take precedence

Abstract

A mechanical load bearing indicator producing signals to a user when the user applies more than selected amounts of load between an extremity of the use and a surface. The indicator has a base plate adapted to establish a frame of reference with the surface, a load plate mounted for movement toward and away from the base plate and adapted to receive loads from the user'"'"'s extremity, and at least two snap domes mechanically engaged between the base plate and the load plate for generating two signals when more than two different respective loads are applied to the load plate by the extremity. The domes are either in series between the plates or are together in a dual dome containing both, or are one or more stacks of domes which individually collapse under incremental loads which are added together to form the selected lower and higher loads.

Claims

1. A mechanical load bearing indicator for producing signals to a user when the user applies more than selected amounts of load between an extremity of the use and a surface, comprising:

a base plate adapted to establish a frame of reference with the surface;

a load plate mounted for movement toward and away from the base plate and adapted to receive loads from the user'"'"'s extremity; and

at least two snap domes mechanically engaged between the base plate and the load plate for generating two signals when more than two different respective and selected loads are applied to the load plate by the extremity.

2. An indicator according to claim 1, wherein the at least two snap domes are engaged in series between the base plate and the load plate so that when a first lower one of the loads is applied to the load plate, a first one of the snap domes collapses and when a second higher one of the loads is applied to the load plate, a second one of the snap domes also collapses.

3. An indicator according to claim 1, wherein each snap dome is made of spring metal.

4. An indicator according to claim 1, wherein each snap dome is made of a plastic.

5. An indicator according to claim 1, wherein the base and the load plates each have a diameter of about 3 to 5 cm, and are adapted for engagement under the user'"'"'s heel or forefoot, the extremity comprising the user'"'"'s foot.

6. An indicator according to claim 1, wherein the base plate with load plate and snap domes have a total height of approximately 0.6 to 1.2 cm.

7. An indicator according to claim 1, wherein the at least two snap domes comprise a low load dome and a high load dome that are integrated into a single dual snap dome having a large diameter base in contact with one of the plates and an apex circle above the one plate in an un-loaded position of the dual dome, and a small diameter dome at the apex circle and in contact with the other of the plates, the large diameter base forming one of the low and high load domes and the small diameter dome forming the other of the low and high load domes.

8. An indicator according to claim 1, wherein one of the snap domes comprises a large diameter dome having an apex recess, the other of the snap domes comprising a small diameter dome nested in the apex recess, the large diameter dome forming one of the low and high load domes and the small diameter dome forming the other of the low and high load domes.

9. An indicator according to claim 1, wherein the at least two snap domes are engaged in series between the base plate and the load plate so that when a first lower one of the loads is applied to the load plate, a first one of the snap domes collapses and when a second higher one of the loads is applied to the load plate, a second one of the snap domes also collapses, at least one of the snap domes comprising a plurality of snap disks in a stack, each snap disk collapsing when an incremental load is applied to that snap disk so that at least one of the selected loads is reached by adding the incremental loads of the snap disks in the stack.

10. An indicator according to claim 1, wherein the at least two snap domes are engaged in series between the base plate and the load plate so that when a first lower one of the loads is applied to the load plate, a first one of the snap domes collapses and when a second higher one of the loads is applied to the load plate, a second one of the snap domes also collapses, each of the snap domes comprising a plurality of snap disks in a stack, each snap disk collapsing when an incremental load is applied to that snap disk so that each of the selected loads is reached by adding the incremental loads of the snap disks in the stack.

11. An indicator according to claim 1, wherein the at least two snap domes are engaged in series between the base plate and the load plate, the indicator including an intermediate plate between the at least two snap domes, and when a first lower one of the loads is applied to the load plate, a first one of the snap domes collapses and when a second higher one of the loads is applied to the load plate, a second one of the snap domes also collapses.

12. An indicator according to claim 1, wherein the at least two snap domes are engaged in series between the base plate and the load plate, the indicator including an intermediate plate between the at least two snap domes, and when a first lower one of the loads is applied to the load plate, a first one of the snap domes collapses and when a second higher one of the loads is applied to the load plate, a second one of the snap domes also collapses, at least one of the snap domes comprising a plurality of snap disks in a stack, each snap disk collapsing when an incremental load is applied to that snap disk so that at least one of the selected loads is reached by adding the incremental loads of the snap disks in the stack.

13. An indicator according to claim 1, wherein the at least two snap domes are engaged in series between the base plate and the load plate, the indicator including an intermediate plate between the at least two snap domes, and when a first lower one of the loads is applied to the load plate, a first one of the snap domes collapses and when a second higher one of the loads is applied to the load plate, a second one of the snap domes also collapses, each snap dome having a concave side with the concave side of one of the snap domes facing the intermediate plate and the concave side of the other snap plate facing either the load plate or the base plate.

14. An indicator according to claim 1, wherein the at least two snap domes are engaged in series between the base plate and the load plate, the indicator including an intermediate plate between the at least two snap domes, and when a first lower one of the loads is applied to the load plate, a first one of the snap domes collapses and when a second higher one of the loads is applied to the load plate, a second one of the snap domes also collapses, each snap dome having a concave side facing the intermediate plate.

15. An indicator according to claim 1, wherein the at least two snap domes are engaged in series between the base plate and the load plate, the indicator including an intermediate plate between the at least two snap domes, and when a first lower one of the loads is applied to the load plate, a first one of the snap domes collapses and when a second higher one of the loads is applied to the load plate, a second one of the snap domes also collapses, each snap dome having a concave side facing away from the intermediate plate.

16. A mechanical load bearing indicator for producing signals to a user when the user applies more than selected amounts of load between an extremity of the use and a surface, comprising:

a base plate adapted to establish a frame of reference with the surface;

a load plate mounted for movement toward and away from the base plate and adapted to receive loads from the user'"'"'s extremity; and

at least two snap domes mechanical engaged between the base plate and the load plate in series with each other for generating two signals when more than two different respective and selected loads are applied to the load plate by the extremity, so that when a first lower one of the loads is applied to the load plate, a first one of the snap domes collapses and when a second higher one of the loads is applied to the load plate, a second one of the snap domes also collapses.

17. An indicator according to claim 16, wherein at least one of the snap domes comprising a plurality of snap disks in a stack, each snap disk collapsing when an incremental load is applied to that snap disk so that at least one of the selected loads is reached by adding the incremental loads of the snap disks in the stack.

18. An indicator according to claim 16, including and intermediate plate between the snap domes.

19. A mechanical load bearing indicator for producing signals to a user when the user applies more than selected amounts of load between an extremity of the use and a surface, comprising:

a base plate adapted to establish a frame of reference with the surface;

a load plate mounted for movement toward and away from the base plate and adapted to receive loads from the user'"'"'s extremity; and

at least two snap domes mechanical engaged between the base plate and the load plate for generating two signals when more than two different respective and selected loads are applied to the load plate by the extremity;

the at least two snap domes comprising a low load dome and a high load dome that are integrated into a single dual snap dome having a large diameter base in contact with one of the plates and an apex circle above the one plate in an un-loaded position of the dual dome, and a small diameter dome at the apex circle and in contact with the other of the plates, the large diameter base forming one of the low and high load domes and the small diameter dome forming the other of the low and high load domes.

20. An indicator according to claim 19, wherein the apex circle includes a recess and the small diameter dome is at the recess.