Portable device for counting and sorting load cycles in supporting structures with various loads

• US 5,763,788 A
• Filed: 04/09/1997
• Issued: 06/09/1998
• Est. Priority Date: 01/25/1996
• Status: Expired due to Term

• Current Assignee: Krauss-Maffei Wegmann GmbH & Company KG (Wegmann GmbH & Co. KG)
• Original Assignee: Mania Technologie AG
• Inventors: Friedhoff, Roland, Kubsch, Gunther
• Primary Examiner(s): Dombroske, George M.
• Assistant Examiner(s): Noori, Max H.
• Application Number:
  US08/831,661
• Time in Patent Office: 426 Days
• Field of Search: 73/763, 73/768, 73/784, 73/786, 73/787, 73/804
• US Class Current: 73/763
• CPC Class Codes: G01B 7/16 for measuring the deformation in a solid, e.g. by resistance strain gauge
• CPC Class Codes: G01M 5/0008 of bridges
• CPC Class Codes: G01M 5/005 by means of external apparatus, e.g. test benches or portable test systems
• CPC Class Codes: G01M 5/0083 by measuring variation of impedance, e.g. resistance, capacitance, induction

Abstract

A device for counting and classifying load cycles in supporting structures with various loads, bridges, cranes, or tracks for example. A measuring instrument (2) is attached to an attachment side (7) of a load-cycle counter (1) and accommodates a mechanical strain amplifier (3). The ends (8 & 8'"'"') of the strain amplifier are much thicker and more resistant to strain. Its middle (9), which includes a strain gauge 10, is much thinner and more sensitive to strain. The ends are fastened to the attachment side. Any signal deriving from traction, force, or flection, and emitted by the strain amplifier (3) is forwarded through a digitalizer (4). The data are processed and stored in a signal processor (5).

Claims

1. An arrangement for counting and classifying load cycles in a supporting structure with changing loads, especially bridges, and for converting local strains arising in the structure into signals, comprising:

a portable, load-cycle counter independent of outside power sources and having a measuring instrument, a mechanical strain amplifier with a strain gauge, a freely programmable digitalizer, a signal processor for programming and reading out data stored by said digitalizer, and a power supply secured to one point on the structure;

a fully closed encapsulated housing holding said arrangement and being simultaneously said mechanical strain amplifier;

said counter carrying out level crossing counting;

said signal processor storing load variations according to load classification and countings, aging of the structure being determined by a specific computation, said housing protecting said arrangement against external disturbances, data from said arrangement being read out on-line over a serial sectional location;

said strain gauge being mounted at a substantially narrowed central part of said mechanical strain amplifier in said measuring instrument;

said load-cycle counter having a mounting wall, said measuring instrument being secured to said mounting wall, said counter receiving the same deformations as said structure;

planar stresses being transformed by stiff strain elements into a soft strain element for processing the transformed strain;

said counter providing remaining life of the structure at specific selection of said level, known life duration and given load spectrum;

said housing being free of outside cables;

said strain gauge having electrical resistance with amplified variations transmitted to said signal processor through said digitalizer.

2. An arrangement as defined in claim 1, wherein said counter is held in a small water-tight protective metal housing;

said data being protected against electromagnetic disturbances.

3. An arrangement as defined in claim 1, wherein said measuring instrument is attached to a side of said load-cycle counter and accommodates said mechanical strain amplifier, said strain amplifier having ends and a middle portion between said ends;

a strain gauge on said middle portion, said ends being thicker and more resistant to strain than said middle portion, said middle portion being thinner and more sensitive to strain than said ends.

4. An arrangement as defined in claim 1, wherein said signal processor is a microprocessor for classifying data and counting and storing applied loads in accordance with their class frequency and retaining the stored applied loads in memory even when the power is interrupted.

5. An arrangement as defined in claim 1, wherein said counter is secured to the structure by screws.

6. An arrangement as defined in claim 1, wherein said counter is secured to the structure by cement.

7. An arrangement as defined in claim 1, wherein said counter is secured to the structure by clamps.

8. An arrangement as defined in claim 1, wherein said power supply is independent of outside sources of power.

9. An arrangement as defined for counting and classifying load cycles in a supporting structure with changing loads, especially bridges, and for converting local strains arising in the structure into signals, comprising:

a portable, load-cycle counter independent of outside power sources and having a measuring instrument, a mechanical strain amplifier with a strain gauge, a freely programmable digitalizer, a signal processor for programming and reading out data stored by said digitalizer, and a power supply secured to one point on the structure;

a fully closed encapsulated housing holding said arrangement and being simultaneously said mechanical strain amplifier;

said counter carrying out level crossing counting;

said signal processor storing load variations according to load classification and countings, aging of the structure being determined by a specific computation, said housing protecting said arrangement against external disturbances, data from said arrangement being read out on-line over a serial sectional location;

said strain gauge being mounted at a substantially narrowed central part of said mechanical strain amplifier in said measuring instrument;

said load-cycle counter having a mounting wall, said measuring instrument being secured to said mounting wall, said counter receiving the same deformations as said structure;

planar stresses being transformed by stiff strain elements into a soft strain element for processing the transformed strain;

said counter providing remaining life of the structure at specific selection of said level, known life duration and given load spectrum;

said housing being free of outside cables;

said strain gauge having electrical resistance with amplified variations transmitted to said signal processor through said digitalizer;

said counter being held in small water-tight protective metal housing, said data being protected against electromagnetic disturbances;

said measuring instrument being attached to a side of said load-cycle counter and accommodating said mechanical strain amplifier, said strain amplifier having ends and a middle portion between said ends;

a strain gauge on said middle portion, said ends being thicker and more resistant to strain than said middle portion, said middle portion being thinner and more sensitive to strain than said ends;

said signal processor being a microprocessor for classifying data and counting and storing applied loads in accordance with their class frequency and retaining the stored applied loads in memory even when the power is interrupted;

said counter being secured to the structure by screws;

said power supply being independent of outside sources of power.