Deformation responsive weighing apparatus

Claim 2

A deformation-responsive weighing apparatus for weighing a load comprising: a substantially straight, longitudinal bar being elastically deformable in response to a load vector applied between the ends thereof; a pair of supporting members, each supporting an end of said bar, each supported end of said bar being free to move relative to its said supporting member about an axis generally perpendicular to a plane defined by the longitudinal axis of said bar and the load vector in response to the load vector being applied to the bar between its ends, thereby permitting linear deformation of the bar while avoiding reverse bending of the bar and the resulting nonlinearities of bar deformation caused by reverse bending; a load applying member on said bar between said supporting members and contacting said bar at a single location to apply a load to the bar at said single location, said load applying member cOoperating with said supporting members to elastically deform said bar when a load is applied to said bar by said load applying member; a plurality of pairs of strain gauges operatively mounted on said bar to detect deformation of said bar caused by forces applied to said bar by loading and to vary their electrical properties in response to such deformation, the two strain gauges comprising each pair of strain gauges being longitudinally spaced apart along said bar with the two gauges of each pair of strain gauges being positioned between said load applying member and one of said load supporting members, the longitudinal distance separating the two gauges of each said pair of strain gauges being substantially equal to the distance separating the two gauges of each of the remaining pairs of gauges; and electrical measuring circuitry operatively connected to said plurality of pairs of strain gauges to measure the changes in electrical properties of said strain gauges and to produce an output representative of the magnitude of the load applied to the bar.

Claim 3

The deformation-responsive weighing apparatus of claim 1 wherein said plurality of pairs of strain gauges includes two pairs of strain gauges on said bar, one pair of strain gauges being positioned between a supporting member and said load applying member and the second pair of strain gauges being positioned between the remaining supporting member and said load applying member.

Claim 4

The deformation-responsive weighing apparatus of claim 1 wherein a pair of said plurality of strain gauges is positioned on a portion of said bar to be exposed to substantial compression and a second pair of strain gauges is positioned on a portion of said bar to be exposed to substantial extension as the bar is deformed by the load.

Claim 5

The deformation-responsive weighing apparatus of claim 1 wherein all strain gauges are positioned on the said bar in a plane defined by the longitudinal axis of the bar and the load vector of the applied load.

Claim 6

The deformation-responsive weighing apparatus of claim 4 wherein one pair of strain gauges is mounted on the bar to detect compression of the bar and a second pair to detect extension of the bar when the bar is deformed by a given load.

Claim 7

The deformation-responsive weighing apparatus of claim 1 wherein said electrical measuring circuitry is an impedance-measuring bridge circuit with first and second current paths between a common energy source, and wherein the two strain gauges comprising each pair of strain gauges are electrically connected in said electrical measuring circuitry such that one strain gauge is in said first current path and the second strain gauge is in said second current path, the two strain gauges comprising each pair of strain gauges being electrically connected in opposite arms of said first and second current paths of said electrical measuring circuitry.

Claim 8

The deformation-responsive weighing apparatus of claim 6 wherein opposite arms of said first and said second current paths include like numbers of said strain gauges electrically connected therein, and the number of strain gauges arranged on the bar to sense compression of said bar being equal to the number of strain gauges arranged on the bar to sense tension of said bar when a given load is applied.

Claim 9

The deformation-responsive weighing apparatus of claim 1 wherein said bar is of uniform, constant diameter circular cross-sectional configuration.

Claim 10

A deformation-responsive weighing apparatus for weighing a load comprising: a substantially straight, longitudinal bar being elastically deformable in response to a load vector applied between the ends thereof; a pair of supporting members, each supporting an end of said bar, each supported end of said bar being free to move relative to its said supporting member about an axis generally perpendicular to a plane defined by the longitudinal axis of said bar and the load vector in response to the load vector being applied to the bar between its ends, thereby permitting linear deformation of the bar while avoiding reverse bending of the bar and the resulting nonlinearities of bar deformation caused by reverse bending; a load applying member on said bar between said supporting members, said load applying member cooperating with said supporting members to elastically deform said bar when a load is applied to said bar by said load applying member; a plurality of pairs of strain gauges operatively mounted on said bar to detect deformation of said bar caused by forces applied to said bar by loading and to vary their electrical properties in response to such deformation; electrical measuring circuitry operatively connected to said plurality of pairs of strain gauges to measure the changes in electrical properties of said strain gauges and to produce an output representative of the magnitude of the load applied to the bar; each said supporting member including a bar mounting socket to receive an end of said bar therein, each said socket having a pin aperture therethrough; said bar having a transverse pin bore adjacent each end thereof, said pin aperture of each socket and the pin bore at an end of said bar forming a continuous passage in said bar and socket, said passge being generally perpendicular to a plane defined by the central axis of the bar and the load vector; and each said supporting member further including a bar retaining pin, positioned within said pin aperture and pin bore at each end of said bar to confine the ends of said bar in said sockets.

Claim 11

A deformation-responsive weighing apparatus for weighing a load comprising: a substantially straight, longitudinal bar being elastically deformable in response to a load vector applied between the ends thereof; a pair of supporting members, each supporting an end of said bar, each supported end of said bar being free to move relative to its said supporting member about an axis generally perpendicular to a plane defined by the longitudinal axis of said bar and the load vector in response to the load vector being applied to the bar between its ends, thereby permitting linear deformation of the bar while avoiding reverse bending of the bar and the resulting nonlinearities of bar deformation caused by reverse bending; a load applying member on said bar between said supporting members, said load applying member cooperating with said supporting members to elastically deform said bar when a load is applied to said bar by said load applying member; a plurality of pairs of strain gauges operatively mounted on said bar to detect deformation of said bar caused by forces applied to said bar by loading and to vary their electrical properties in response to such deformation; electrical measuring circuitry operatively connected to said plurality of pairs of strain gauges to measure the changes in electrical properties of said strain gauges and to produce an output representative of the magnitude of the load applied to the bar; each said supporting member including a bar mounting socket to receive an end of said bar therein, each said socket having a pin aperture therethrough; said bar having a transverse pin bore adjacent each end thereof, said pin aperture of each socket and the pin bore at an end of said bar forming a continuous passage in said bar and socket, said passge being generally perpendicular to a plane defined by the central axis of the bar and the load vector; and each said supporting member further including a bar retaining pin, positioned within said pin aperture and pin bore at each end of said bar to confine the ends of said bar in said sockets.

Claim 12

The deformation-responsive weighing apparatus of claim 9 wherein said pins are of smaller diameter than said pin bores in said bar permitting said bar to undergo small movements about the pins to thereby substantially eliminate undesirable extraneous deformations in said bar.

Claim 13

A deformation-responsive weighing apparatus for weighing a load comprising: a substantially straight, longitudinal bar being elastically deformable in response to a load vector applied between the ends thereof; a pair of supporting members, each supporting an end of said bar, each supported end of said bar being free to move relative to its said supporting member about an axis generally perpendicular to a plane defined by the longitudinal axis of said bar and the load vector in response to the load vector being applied to the bar between its ends, thereby permitting linear deformation of the bar while avoiding reverse bending of the bar and the resulting nonlinearities of bar deformation caused by reverse bending; a load applying member on said bar between said supporting members, said load applying member cooperating with said supporting members to elastically deform said bar when a load is applied to said bar by said load applying member; a plurality of pairs of strain gauges operatively mounted on said bar to detect deformation of said bar caused by forces applied to said bar by loading and to vary their electrical properties in response to such deformation; electrical measuring circuitry operatively connected to said plurality of pairs of strain gauges to measure the changes in electrical properties of said strain gauges and to produce an output representative of the magnitude of the load applied to the bar; said load-applying member having a pin aperture therethrough; said bar having a pin bore communicating with said pin aperture, said aperture and bore forming a passage generally perpendicular to a plane defined by the longitudinal axis of said bar and the load vector; and a retaining pin in said passage to retain the said load-applying member on said bar with minimal generation of extraneous deformation.

Claim 14

A deformation-responsive weighing apparatus for weighing a load comprising: a substantially straight, longitudinal bar being elastically deformable in response to a load vector applied between the ends thereof; a pair of supporting members, each supporting an end of said bar, each supported end of said bar being free to move relative to its said supporting member about an axis generally perpendicular to a plane defined by the longitudinal axis of said bar and the load vector in response to the load vector being applied to the bar between its ends, thereby permitting linear deformation of the bar while avoiding reverse bending of the bar and the resulting nonlinearities of bar deformation caused by reverse bending; a load applying member on said bar between said supporting members, said load applying member cooperating with said supporting members to elastically deform said bar when a load is applied to said bar by said load applying member; a plurality of pairs of strain gauges operatively mounted on said bar to detect deformation of said bar caused by forces applied to said bar by loading and to vary their electrical properties in response to such deformation; electrical measuring circuitry operatively connected to said plurality of pairs of strain gauges to measure the changes in electrical properties of said strain gauges and to produce an output representative of the magnitude of the load applied to the bar; said load-applying member having a pin aperture therethrough; said bar having a pin bore communicating with said pin aperture, said aperture and bore forming a passage generally perpendicular to a plane defined by the longitudinal axis of said bar and the load vector; and a retaining pin in said passage to retain the said load-applying member on said bar with minimal generation of extraneous deformation.

Claim 15

A deformation-responsive weighing apparatus for weighing a load comprising: a substantially straight, longitudinal bar of uniform, circular cross-sectional configuration being elastically deformable in response to a load vector applied between the ends thereof; a paiR of supporting members, one of said members being adjacent each end of said bar and supporting an end of said bar; a load applying member on said bar between said supporting members and contacting said bar at a single location to apply a load to the bar at said single location, said load applying member cooperating with said supporting members to elastically deform said bar when a load is applied to said bar by said load applying member; a plurality of pairs of strain gauges operatively mounted on said bar to detect deformation of said bar caused by forces applied to said bar by loading and to vary their electrical properties in response to such deformation, the two strain gauges comprising each pair of strain gauges being longitudinally spaced apart along said bar with the two gauges of each pair of strain gauges being positioned between said load applying member and one of said load supporting members, the longitudinal distance separating the two gauges of each said pair of strain gauges being substantially equal to the distance separating the two gauges of each of the remaining pairs of gauges; and electrical measuring circuitry operatively connected to said plurality of pairs of strain gauges to measure the changes in electrical properties of said strain gauges and to produce an output representative of the magnitude of the load applied to the bar.

Claim 16

A deformation-responsive weighing apparatus for weighing a load comprising: a substantially straight, longitudinal bar of uniform, circular cross-sectional configuration being elastically deformable in response to a load vector applied between the ends thereof; a paiR of supporting members, one of said members being adjacent each end of said bar and supporting an end of said bar; a load applying member on said bar between said supporting members and contacting said bar at a single location to apply a load to the bar at said single location, said load applying member cooperating with said supporting members to elastically deform said bar when a load is applied to said bar by said load applying member; a plurality of pairs of strain gauges operatively mounted on said bar to detect deformation of said bar caused by forces applied to said bar by loading and to vary their electrical properties in response to such deformation, the two strain gauges comprising each pair of strain gauges being longitudinally spaced apart along said bar with the two gauges of each pair of strain gauges being positioned between said load applying member and one of said load supporting members, the longitudinal distance separating the two gauges of each said pair of strain gauges being substantially equal to the distance separating the two gauges of each of the remaining pairs of gauges; and electrical measuring circuitry operatively connected to said plurality of pairs of strain gauges to measure the changes in electrical properties of said strain gauges and to produce an output representative of the magnitude of the load applied to the bar.