Tension sensor

Claim 3

The apparatus as in claim 1 wherein said load plate includes guide means to align the load plate relative to the support means and flexure member, the guide means being slidably operative with the flexure member.

Claim 4

The apparatus as in claim 2 wherein said guide means comprises a guide post connected to the load plate.

Claim 5

The apparatus as in claim 1 wherein said load plate has a lower surface which is wedge shaped in cross section.

Claim 6

The apparatus as in claim 4 wherein said support means has a wedge shaped depression corresponding to the wedge shaped surface of the load plate.

Claim 7

The apparatus as in claim 1 wherein said support means is removably mounted to the frame.

Claim 8

The apparatus as in claim 1 wherein said means for adjusting the load plate comprises an adjustment mechanism joined to the flexure member, the adjustment mechanism adjusting the relative spacing between the load plate and the flexure member.

Claim 9

The apparatus as in claim 7 wherein said adjustment mechanism comprises a threaded rod mating with a threaded aperture in the flexure member.

Claim 10

The apparatus as in claim 8 and further comprising a beam joined to said flexure member, said beam having said threaded aperture.

Claim 11

The apparatus as in claim 9 wherein said beam is joined to said connector wall.

Claim 12

The apparatus as in claim 9 wherein said beam is disposed between said parallel plates.

Claim 13

The apparatus as in claim 9 and further comprising a guide post connected to the load plate, and wherein said beam includes a guide aperture, said guide post being slidable within said guide aperture to align said load plate with said support means.

Claim 14

The apparatus as in claim 9 and further comprising a plurality of guide posts connected to the load plate, and wherein said beam includes a plurality of guide apertures, each said guide post being slidable within one of the guide apertures to align said load plate with said support means.

Claim 15

A force sensor for determining tension forces present in a portion of tissue surrounding a body joint, the force sensor comprising: a frame; a flexure member cantilevered from the frame, the flexure member comprising parallel flexure plates and a connector wall, the flexure plates having first ends thereof attached to the frame and second ends thereof joined with the connector wall; a load plate mounted to the flexure member; support means mounted to said frame and opposite said load plate for supporting a portion of tissue to be measured; sensing means mounted to the flexure member for sensing tension forces, the tension forces being transferred from the load plate to the flexure member; a press assembly acting on the load plate to clamp the tissue between the load plate and the support means; and guide means operatively connected to the load plate and the flexure member for aligning the load plate relative to the support means and flexure member as the press assembly clamps the tissue between the load plate and the support means.

Claim 16

A force sensor for determining tension forces present in a portion of tissue surrounding a body joint, the force sensor comprising: a frame; a flexure member cantilevered from the frame, the flexure member comprising parallel flexure plates and a connector wall, the flexure plates having first ends thereof attached to the frame and second ends thereof joined with the connector wall; a load plate mounted to the flexure member; support means mounted to said frame and opposite said load plate for supporting a portion of tissue to be measured; sensing means mounted to the flexure member for sensing tension forces, the tension forces being transferred from the load plate to the flexure member; a press assembly acting on the load plate to clamp the tissue between the load plate and the support means; and guide means operatively connected to the load plate and the flexure member for aligning the load plate relative to the support means and flexure member as the press assembly clamps the tissue between the load plate and the support means.

Claim 17

The apparatus as in claim 14 wherein said guide means comprises guide posts connected to said load plate that are slidably guided relative to the flexure member.

Claim 18

The apparatus as in claim 14 wherein said sensing means is a strain gage.

Claim 19

The apparatus as in claim 14 wherein the press assembly is joined to the flexure member and the load plate.

Claim 20

The apparatus as in claim 17 wherein the press assembly comprises an adjustment mechanism joined to the flexure member, the adjustment mechanism adjusting the relative spacing between the load plate and the flexure member.

Claim 21

The apparatus as in claim 18 wherein said adjustment mechanism comprises a threaded rod mating with a threaded aperture in the flexure member.

Claim 22

The apparatus as in claim 19 and further comprising a beam joined to said flexure member, said beam having said threaded aperture.

Claim 23

The apparatus as in claim 20 wherein said beam is joined to the connector wall.

Claim 26

The apparatus as in claim 22 wherein the sensor assembly includes adjusting means connected to said load plate, and wherein the step of compressing comprises adjusting said adjusting means to apply a selected compression force to said tissue.

Claim 27

The method as in claim 23 wherein the sensor assembly includes a frame joined to said support plate, and wherein said flexure member is cantilevered from said frame and comprises spaced parallel flexure plates and a connector wall, the flexure plates having first ends thereof attached to the frame, and second ends thereof joined with the connector wall.

Claim 28

The method as in claim 22 wherein said support plate is detachable from said sensor assembly, and wherein the method includes, after the step of providing the output signal, detaching the sensor assembly from said support plate with said support plate remaining in contact with said tissue.

Claim 29

The method as in claim 25 and after the step of detaching the sensor assembly, including the steps: attaching said support plate to said sensor assembly; recompressing the tissue between said load plate and said support plate; generating a second force in said tissue; sensing the second force transferred from said load plate to said flexure member; and providing a second output signal from the flexure sensing device representative of the second force.

Claim 30

The method as in claim 26 wherein the step of recompressing comprises adjusting said adjusting means to reapply substantially the selected compression force to said tissue.