The following operators can be used to better focus your queries.
( ) , AND, OR, NOT, W/#
? single char wildcard, not at start
* multi char wildcard, not at start
(Cat? OR feline) AND NOT dog?
Cat? W/5 behavior
(Cat? OR feline) AND traits
Cat AND charact*
This guide provides a more detailed description of the syntax that is supported along with examples.
This search box also supports the look-up of an IP.com Digital Signature (also referred to as Fingerprint); enter the 72-, 48-, or 32-character code to retrieve details of the associated file or submission.
Concept Search - What can I type?
For a concept search, you can enter phrases, sentences, or full paragraphs in English. For example, copy and paste the abstract of a patent application or paragraphs from an article.
Concept search eliminates the need for complex Boolean syntax to inform retrieval. Our Semantic Gist engine uses advanced cognitive semantic analysis to extract the meaning of data. This reduces the chances of missing valuable information, that may result from traditional keyword searching.
This system allows a simple and accurate method for ascertaining the number of turns in a coil winding, such as the rotational field coils used in bubble memories and the like.
English (United States)
This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately
92% of the total text.
Page 1 of 2
Moire System for Counting Winding Turns
This system allows a simple and accurate method for ascertaining the
number of turns in a coil winding, such as the rotational field coils used in bubble
memories and the like.
In the present system, a calibrated moire or line grating 10 with a spatial
frequency f is placed in contact over the coil 11 under test of known length L.
The grating lines are oriented parallel to the winding turns. As a result, an optical
interference pattern, i.e., moire effect pattern, appears through the grating 10
(Fig. 2). Grating 11 is manipulated in the direction X until the coarsest pattern is
observed, at which time the number N of interference fringes in the pattern is
The moire effect is essentially a heterodyning action, whereby
the spatial frequency F of the coil turns, i.e., the number of turns
per inch, is beat down to a lower spatial frequency by a constant
local oscillator or carrier frequency, i.e., the spatial frequency f
of the moire grid 10. Thus, the number F of turns per inch of coil
11 is determined by:
(1) F = f+N/L
The sign ambiquity in equation (1) is eliminated by sliding grating 10 over coil
11 away, i.e., minus X direction, from the observer. If the observed interference
pattern moves in the same direction as the grating, the negative sign is used in
equation (1). If the pattern moves in a direction opposite to the direction of the
grating 11, the positive sign is used.