Device for sampling data for fatigue analysis by rainflow method

• US 5,847,668 A
• Filed: 01/30/1997
• Issued: 12/08/1998
• Est. Priority Date: 03/28/1996
• Status: Expired due to Term

• Current Assignee: Yukitaka Murakami
• Original Assignee: Fukuoka Kiki Co., Ltd.
• Inventors: Murakami, Yukitaka, Morita, Takumi
• Primary Examiner(s): Hoff, Marc S.
• Assistant Examiner(s): JEAN PIERRE, PEGUY
• Application Number:
  US08/791,304
• Time in Patent Office: 677 Days
• Field of Search: 341/155, 341/132, 364/508, 73/760
• US Class Current: 341/132
• CPC Class Codes: G01N 2203/0073 Fatigue
• CPC Class Codes: G01N 2203/0617 Electrical or magnetic indicating, recording or sensing means
• CPC Class Codes: G07C 3/00 Registering or indicating the condition or the working of machines or other apparatus, other than vehicles

Abstract

To more accurately and more simply realize data collection and analysis for analyzing fatigue phenomenon of materials by the Rainflow Method, strain signals from a strain detecting means attached to an object for analyzing fatigue is A/D-converted at predetermined intervals, a peak of the A/D-converted strain signal is sampled, the peak value is detected, a valley is sampled, the valley value is detected, the difference between the peak value and the valley value is calculated, count values for respective levels are calculated in accordance with the magnitudes of the differences and the count values at the respective levels are written to a memory card detachably provided to the main body of the device of sampling data.

Claims

1. A device for sampling data for fatigue analysis by the Rainflow Method, comprising:

means for A/D converting at predetermined intervals a strain signal from a strain detecting means attached to an object for analyzing fatigue;

means for sampling a peak of the A/D-converted strain signal and detecting a peak value thereof;

means for sampling a valley of the A/D-converted strain signal and detecting a valley value thereof;

means for calculating a difference peak value and the valley value;

means for counting the difference as a count value representing a frequency of occurrences of any one of a predetermined plurality of levels in accordance with an amount of the difference;

a memory card detachably provided to a main body of the device for sampling data including at least the means for A/D converting the strain signal, the means for detecting the peak value of the strain signal, the means for detecting the valley value of the strain signal, the means for calculating the difference between the peak value and the valley value and the means for counting the difference; and

means for writing said count value of the difference at each of the plurality of levels on the memory card.

2. The device for sampling data for fatigue analysis by the Rainflow Method according to claim 1, further comprising:

means for storing a value of the A/D-converted strain signal at an initial loading state as a correction value; and

means for correcting the A/D-converted strain signal by the correction value in sampling data for fatigue analysis.