Joseph Chedaker, George Gilbert Hoberg and Eugene Arthur Sands v. Arthur W. Lo

318 F.2d 333, 50 C.C.P.A. 1556, 138 U.S.P.Q. (BNA) 55, 1963 CCPA LEXIS 327
CourtCourt of Customs and Patent Appeals
DecidedJune 20, 1963
DocketPatent Appeal 6921
StatusPublished
Cited by2 cases

This text of 318 F.2d 333 (Joseph Chedaker, George Gilbert Hoberg and Eugene Arthur Sands v. Arthur W. Lo) is published on Counsel Stack Legal Research, covering Court of Customs and Patent Appeals primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Joseph Chedaker, George Gilbert Hoberg and Eugene Arthur Sands v. Arthur W. Lo, 318 F.2d 333, 50 C.C.P.A. 1556, 138 U.S.P.Q. (BNA) 55, 1963 CCPA LEXIS 327 (ccpa 1963).

Opinion

ALMOND, Judge.

This appeal is from the decision of the Board of Patent Interferences which awarded priority of invention in Interference No. 89,337 to the junior party Lo, patentee named in U. S. Patent 2,818,555. 1 Appellants Chedaker et al. are senior by virtue of the earlier filing date of their application 2 in which claims 8 and 12 of the Lo patent, corresponding to the counts in issue, were copied and added by amendment. The board found no support in the Chedaker et al. application for the copied claims.

The counts relate to a magnetic device and associated windings useful in the storage and control of electrical signals representing information. The magnetic material employed has the characteristic of a “rectangular hysteresis loop.” This term is derived from the graphical presentation obtained when magnetizing force is plotted against the magnetic flux density produced in the material. The resulting curve, called the hysteresis curve or loop, takes on a roughly rectangular shape.

In practical effect, such a hysteresis curve or loop indicates that the material has high magnetic remanence or retentivity. This means that if the material is magnetized in one direction by an applied magnetizing force, which may be created by current flow through a winding associated therewith, it will remain magnetized in that direction even after the magnetizing force is removed, i. e., it “remembers” the flux direction. Similarly, when a magnetizing force is applied in the opposite direction and then removed, the material will remain magnetized in the opposite direction. There is an abrupt transition between flux in one magnetic state and flux in the opposite state. In each state, the remanent flux is nearly equal to the saturation flux of material characterized as having a square hysteresis loop.

Since there are two stable “states,” or “senses,” depending on the direction of the applied magnetic force, with an abrupt change between these states when the direction of the magnetizing force is reversed, the material is capable of “remembering” which of the two forces was last applied.

There are two counts in issue. Count 1 is illustrative and reads:

“1. A magnetic device comprising a unitary core of magnetic material characterized by having a substantially rectangular hysteresis, loop, said core having a plurality of apertures therein, means for producing a magnetic flux completely around said core in one sense, and a winding wound through a first and a second of said apertures exclusively so that, when energized by a pulse of' either polarity, the magnetizing-force generated thereby will produeea flux change from said one sense to. the sense opposite the one sense in at least a portion of said core adjacent a third of said apertures.”

The language of the counts gives rise-to two issues of interpretation. The first is whether the phrase “characterized by having a substantially rectangular hysteresis loop” modifies the word “core” or-the word “material.” The Chedaker et al. device uses material having such a. characteristic but not a core so characterized over-all.

The second issue is whether the Chedaker et al. disclosure shows a winding in which, “when energized by a pulse of either polarity, the magnetizing force generated thereby will produce a flux change from said one sense to the sense-opposite the one sense * * Appel *335 lant contends that there is such a disclosure ; appellee, the contrary.

As to the first issue, the record shows that each of the parties employs magnetic material which is characterized as having a rectangular hysteresis loop. When a core is made from such material, however, it may or may not have a rectangular hysteresis loop, depending on the geometry or configuration of the core.

The core disclosed in appellee’s patent is a disc of magnetic material having a number of apertures therein. Each aperture has a function in the operation of the device. In the center of the disc is the blocking aperture, through which a winding is passed. When a uni-directional current pulse of sufficient amplitude is applied to this winding, the entire core is saturated with flux in one direction, placing it in what appellee describes as a blocked condition.

A pair of smaller setting apertures are symmetrically located in the disc on either side of the larger diameter blocking aperture. A winding extends through those apertures from a setting-pulse source. The windings are so arranged that a pulse of either a positive or negative polarity from the source unblocks the core by changing the flux direction in a portion of the core.

A third essential aperture in appellee’s device is designated an output aperture. Passing through this aperture is an input winding adapted to receive a .signal pulse and a separate output winding which responds to the signal pulse by producing an output which is indicative of whether the core is blocked or has been unblocked by reason of a setting pulse which was applied to the winding passing through the setting apertures.

While more apertures may be present, the minimum number disclosed by the Lo patent is four, to wit: a blocking aperture, two setting apertures and an output aperture. A feature of practical importance in appellee’s device is that a setting pulse of either polarity in the winding through the setting apertures produces a reversal of the flux direction in the path between the output aperture and the blocking aperture. While a positive setting pulse reverses a different portion of the blocked core than that reversed by a negative setting pulse, the reversed portions overlap so that each pulse reverses the portion of the core between the output aperture and the blocking aperture. Since the flow of flux around the output aperture is changed, the induced voltage in the output winding indicates either a blocked or an unblocked response, whether the unblocked response is a result of a positive or a negative setting pulse.

The core disclosed in the Lo patent is so constructed that the entire device exhibits the characteristic of a rectangular hysteresis loop so that the blocked condition may control all parts of the core. With some geometric configurations, the flux density might not be saturated in all portions of the core, so that some portions might indicate no strong flux direction (i. e., these portions might “forget” the last applied magnetic force), even though the composition of the core is a rectangular hysteresis loop material.

In appellants’ device, as disclosed in the Chedaker et al. application, it is not desired to have each portion of the core saturated with flux. Only one portion of the multi-apertured core in Chedaker et al. must be maintained at high flux density. In the remainder of the core, air gaps are introduced in the paths where high remanence is not required to concentrate the remanence flux in the critical paths. Alternatively, Chedaker et al. state in the specification that “it may be advantageous to make only the core section DGHF [the section providing the memory function] from a high remanence, high coercivity material and make the remainder of the core from a high permeability, low coercivity material.”

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318 F.2d 333, 50 C.C.P.A. 1556, 138 U.S.P.Q. (BNA) 55, 1963 CCPA LEXIS 327, Counsel Stack Legal Research, https://law.counselstack.com/opinion/joseph-chedaker-george-gilbert-hoberg-and-eugene-arthur-sands-v-arthur-w-ccpa-1963.