Weighing apparatus

Claim 2

A load measuring apparatus comprising a parallelogramic link system including an upright frame member, an upright load receiving member parallel to but spaced from the frame member, and a plurality of parallel flexure strips forming a top linkage and a bottom linkage connecting the frame member and load receiving member for movement of the latter in a substantially vertical path; and a plurality of strain gauges mounted on the flexure strips to furnish electrical signals representative of a load producing deflection of the flexure strips; characterized in that the flexure strips are three in number of which first (20) and second (21) strips are in spaced, parallel horizontal coplanar relationship to form one of the linkages and the third flexure strip (25) is spaced vertically from said pair to form the other linkage, and in that all the strain gauges (29, 30, 31, 32) are mounted on said third flexure strip.

Claim 3

A load measuring apparatus according to claim 1 characterized in that the resistance to deflection of the flexure strips (20, 21, 25) constitutes the whole of load measuring resistance of the apparatus and the resistance of the third strip (25) equals the sum of the resistances of the first and second strips (20, 21).

Claim 4

A load measuring apparatus according to claim 1 characterized in that the pair of first and second flexure strips (21, 22) constitute the top linkAge and the third flexure strip (25) constitutes the bottom linkage.

Claim 5

A load measuring apparatus according to claim 1 characterized by a dash-pot (27) connected between relatively movable parts of the load-receiving member (16) and a frame structure (10) of the apparatus including the frame member.

Claim 6

A load measuring apparatus as defined in claim 1, wherein each of said flexure strips is fixed at one end to said frame member and at the opposite end to said load receiving member.

Claim 7

A load measuring apparatus according to claim 1, characterized in that there are four strain gauges (29, 30, 31, 32) mounted two (29, 30) on an upper surface and two (31, 32) on a lower surface of said third flexure strip (25) immediately beneath the upper two gauges.

Claim 8

A load measuring apparatus according to claim 6 characterized in that the strain gauges, (29, 30, 31, 32) are mounted by bonding and are electrically interconnected, said bonded gauges and electrical inter-connections being sealed with a moisture proofing compound.

Claim 9

A load measuring apparatus according to claim 6 characterized in that the four strain gauges (29, 30, 31, 32) are electrically interconnected in a Wheatstone''s Bridge arrangement for furnishing said electrical signals.

Claim 10

A load measuring apparatus comprising a parallelogramic link including an upright frame member, an upright load receiving member parallel to but spaced from the frame member, and a plurality of parallel flexure strips forming a top linkage and a bottom linkage connecting the frame member and load receiving member for movement of the latter in a substantially vertical path, said flexure strips being three in number of which first and second strips are in spaced parallel horizontal co-planar relationship to form a first of said linkages and the third strip is spaced vertically from said pair to form a second of said linkages, means for adjusting the position of attachment to said frame member of one of the linkages relative to the position of attachment of the other linkage, and a plurality of strain gauges all mounted on said third flexure strip to furnish electrical signals representative of the magnitude of a load applied to said load receiving member and causing deflection of said strips.

Claim 11

A load measuring apparatus comprising a parallelogramic link including an upright frame member, an upright load receiving member parallel to but spaced from the frame member, and a plurality of parallel flexure strips forming a top linkage and a bottom linkage connecting the frame member and load receiving member for movement of the latter in a substantially vertical path, said flexure strips being three in number of which first and second strips are in spaced parallel horizontal co-planar relationship to form a first of said linkages and the third strip is spaced vertically from said pair to form a second of said linkages, means for adjusting the position of attachment to said frame member of one of the linkages relative to the position of attachment of the other linkage, and a plurality of strain gauges all mounted on said third flexure strip to furnish electrical signals representative of the magnitude of a load applied to said load receiving member and causing deflection of said strips.

Claim 12

A load measuring apparatus according to claim 9 wherein said one linkage is said first linkage and the adjustment means is operable to adjust the position of attachment of each of said first and second flexure strips independently of the other.

Claim 13

A load measuring apparatus according to claim 9 wherein the resistance to deflection of said three flexure strips constitutes the whole load measuring resistant of the apparatus and the resistance of said third strip equals the sum of the resistances of said first and second strips.

Claim 14

A load measuring apparatus according to claim 9 wherein said first linkage constituted by the pair of first and second flexure strips in the top linkage, and said second linkage constituted by the third flexure strip in the bottom linkage.

Claim 15

A load measuring apparatus according to claim 9 including a dash-pot connected between relatively movable parts of the load-receiving member and a frame structure of the apparatus including the frame member.

Claim 16

A load measuring apparatus according to claim 9 having four strain gauges mounted two on an upper surface of said third flexure strip and two on a lower surface thereof immediately beneath the upper two gauges.

Claim 17

A load measuring apparatus according to claim 14 wherein the strain gauges are mounted by bonding and are electrically interconnected, said bonded gauges and electrical interconnections being sealed with a moisture proofing compound.

Claim 18

A load measuring apparatus according to claim 14 wherein the four strain gauges are electrically interconnected in a Wheatstone''s Bridge arrangement for furnishing said electrical signals.