US4231107A — Serriform strip crosstie memory

Claim 1

Independent Claim 94 words

In a logic system, a serially accessible crosstie memory element, comprising: a ferromagnetic oblong layer having, denticulated margins parallel to and symmetric about the oblong centerline of the layer; and, electrical means external to, electrically insulated from, and running along the centerline of said ferromagnetic layer for creating a field pattern on said ferromagnetic layer; whereby along said centerline a domain wall may be positioned, and along said domain wall crossties may be nucleated at and Bloch lines may be nucleated between, opposite narrow cross-sections of said margins, and Bloch lines may be propelled.

Claim 2

Dependent Claim 94 words

In a logic system, a serially accessible crosstie memory element, comprising: a ferromagnetic oblong layer having, denticulated margins parallel to and symmetric about the oblong centerline of the layer; and, electrical means external to, electrically insulated from, and running along the centerline of said ferromagnetic layer for creating a field pattern on said ferromagnetic layer; whereby along said centerline a domain wall may be positioned, and along said domain wall crossties may be nucleated at and Bloch lines may be nucleated between, opposite narrow cross-sections of said margins, and Bloch lines may be propelled.

Claim 3

Dependent Claim 26 words

In a logic system as set forth in claim 1 wherein the memory element comprises said oblongly ferromagnetic layer terminating with at least one aculeate extremity.

Claim 4

Dependent Claim 19 words

In a logic system as set forth in claim 2 wherein said aculeate extremity is bisected by said centerline.

Claim 5

Dependent Claim 25 words

In a logic system as set forth in claim 1 wherein the memory element comprises said ferromagnetic layer terminating with at least one homecercal extremity.

Claim 6

Dependent Claim 19 words

In a logic system as set forth in claim 4 wherein said homocercal extremity is bisected by said centerline.

Claim 7

Dependent Claim 82 words

In a logic system, a crosstie memory element, comprising an oblongly ferromagnetic layer, longitudinally bounded by a pair of mirror image denticulated margins parallel to and symmetric about the centerline of the layer, each margin formed by an equal plurality of opposite, equally spaced abutting denticles, each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon the centerline exceeds the projected length of its minor edge upon the same centerline.

Claim 8

Dependent Claim 82 words

In a logic system, a crosstie memory element, comprising an oblongly ferromagnetic layer, longitudinally bounded by a pair of mirror image denticulated margins parallel to and symmetric about the centerline of the layer, each margin formed by an equal plurality of opposite, equally spaced abutting denticles, each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon the centerline exceeds the projected length of its minor edge upon the same centerline.

Claim 9

Dependent Claim 110 words

A logic system as set forth in claim 6 wherein said memory element comprises an oblongly serriform ferromagnetic layer having at least one acutely aculeate extremity formed by one or more edges on either side of said centerline such that on both sides of said centerline the length of the projection upon said centerline of those edges having a slope with the same sign with respect to said centerline as the sign of the slopes of said major edges on the same side of said centerline exceeds the length of the projection upon said centerline of all other edges forming the aculeate extremity on the same side of said centerline.

Claim 10

Dependent Claim 108 words

A logic system as set forth in claim 6 wherein said memory comprises an oblongly serriform ferromagnetic layer having at least one homocercal extremity formed by one or more edges on either side of said centerline such that on both sides of said centerline the length of the projection upon said centerline of those edges having a slope with the same sign with respect to said centerline as the sign of the slopes of said major edges on the same side of said centerline exceeds the length of the projection upon said centerline of all other edges forming the aculeate extremity on the same side of said centerline.

Claim 11

Dependent Claim 158 words

In a logic system, a crosstie memory element, comprising: an oblongly ferromagnetic layer longitudinally bounded by denticulated margins parallel to and symmetric about its centerline, each margin formed by an equal plurality of oppositely spaced and similarly oriented abutting denticles, each denticle having a first outside edge of length A intersecting a second outside edge of length B, the first edge potentially forming an angle θ with said centerline and the second edge potentially forming an angle φ with said centerline, wherein: A SINE 2θ>B SINE 2 φ; and external and electrically insulated main conductor means for creating a field pattern on said ferromagnetic layer; whereby along said centerline a domain wall may be positioned on which crossties may be nucleated at and Bloch lines may be nucleated between opposite narrow cross-sections of said margins, and Bloch lines may be propelled in response to the introduction of electrical currents of selected magnitude and direction into said main conductor.

Claim 12

Dependent Claim 158 words

In a logic system, a crosstie memory element, comprising: an oblongly ferromagnetic layer longitudinally bounded by denticulated margins parallel to and symmetric about its centerline, each margin formed by an equal plurality of oppositely spaced and similarly oriented abutting denticles, each denticle having a first outside edge of length A intersecting a second outside edge of length B, the first edge potentially forming an angle θ with said centerline and the second edge potentially forming an angle φ with said centerline, wherein: A SINE 2θ>B SINE 2 φ; and external and electrically insulated main conductor means for creating a field pattern on said ferromagnetic layer; whereby along said centerline a domain wall may be positioned on which crossties may be nucleated at and Bloch lines may be nucleated between opposite narrow cross-sections of said margins, and Bloch lines may be propelled in response to the introduction of electrical currents of selected magnitude and direction into said main conductor.

Claim 13

Dependent Claim 66 words

In a logic system as set forth in claim 9, a memory element including auxiliary electrical means comprising for each said denticulated margins a crenelated auxiliary electrical conductor external to, partially overlying the surface of, and electrically insulated from said ferromagnetic layer whereby only alternate denticles are overlain in each margin with only one denticle of each pair of opposite denticles overlain by the auxiliary conductor.

Claim 14

Dependent Claim 106 words

A serially accessible memory element for the storage and propagation of crosstie-Bloch line pairs, comprising: a ferromagnetic strip bordered along each of its oblong edges by a plurality of uniformily oriented denticles arranged in a spaced relation to those denticles bordering the opposite edge, each denticle described by a first chord of length A having a projecting end meeting one end of a second chord of length B and a recessed end potentially intersecting the centerline of the strip at an angle θ, the unmet end of the second chord potentially intersecting the centerline of the strip at an angle φ, wherein: A·SINE 2θ>B·SINE 2 φ.

Claim 15

Dependent Claim 106 words

A serially accessible memory element for the storage and propagation of crosstie-Bloch line pairs, comprising: a ferromagnetic strip bordered along each of its oblong edges by a plurality of uniformily oriented denticles arranged in a spaced relation to those denticles bordering the opposite edge, each denticle described by a first chord of length A having a projecting end meeting one end of a second chord of length B and a recessed end potentially intersecting the centerline of the strip at an angle θ, the unmet end of the second chord potentially intersecting the centerline of the strip at an angle φ, wherein: A·SINE 2θ>B·SINE 2 φ.

Claim 16

Dependent Claim 19 words

The ferromagnetic strip set forth in claim 11 further comprising said plurality of denticles arranged in abutting jugate pairs.

Claim 17

Dependent Claim 23 words

The ferromagnetic strip set forth in claim 11 further comprising said plurality of denticles separated by a baselength C wherein: C=A·COSINE θ+B·COSINE φ.

Claim 18

Dependent Claim 27 words

The ferromagnetic strip set forth in claim 11 further comprising said plurality of denticles arranged in jugate pairs separated by a baselength C wherein: C=2[A·COSINE θ+B·COSINE φ].

Claim 19

Dependent Claim 18 words

The ferromagnetic strip set forth in claim 13 further comprising said plurality of denticles arranged in jugate pairs.

Claim 20

Dependent Claim 24 words

The ferromagnetic strip set forth in claim 13 further comprising said plurality of denticles arranged along opposite of said edges in an alternate sequence.

Claim 21

Dependent Claim 19 words

The ferromagnetic strip set forth in claim 14 further comprised of said plurality of denticles arranged in jugate pairs.

Claim 22

Dependent Claim 25 words

The ferromagnetic strip set forth in claim 14 further comprised of said plurality of denticles arranged along opposite of said edges in an alternate sequence.

Claim 23

Dependent Claim 180 words

In a crosstie memory system of the type using an oblongly detate ferromagnetic layer with oppositely directed induced magnetic domains separated by a domain wall running along its length, and with opposite denticles defining individual memory cells, the layer overlain with and electrically insulated from a single electrical conductor for applying magnetic field patterns along the length of the layer, the process of propagating along the domain wall binary information represented by the presence of crosstie-Bloch line pairs, comprising the steps of: applying via said single conductor a magnetic propagation pulse in a negative direction perpendicular to the centerline of said layer whereby for each existing crosstie-Bloch line pair the Bloch line is propelled into the next memory cell; applying via said single conductor a magnetic annihilation pulse having a magnitude sufficient to propel each last nucleated Bloch line to the position occupied by the nearest previously existing crosstie but of magnitude insufficient to propel any pre-existing Bloch line to the position occupied by the last nucleated crosstie, in a positive direction perpendicular to the easy axes of said layer.

Claim 24

Dependent Claim 180 words

In a crosstie memory system of the type using an oblongly detate ferromagnetic layer with oppositely directed induced magnetic domains separated by a domain wall running along its length, and with opposite denticles defining individual memory cells, the layer overlain with and electrically insulated from a single electrical conductor for applying magnetic field patterns along the length of the layer, the process of propagating along the domain wall binary information represented by the presence of crosstie-Bloch line pairs, comprising the steps of: applying via said single conductor a magnetic propagation pulse in a negative direction perpendicular to the centerline of said layer whereby for each existing crosstie-Bloch line pair the Bloch line is propelled into the next memory cell; applying via said single conductor a magnetic annihilation pulse having a magnitude sufficient to propel each last nucleated Bloch line to the position occupied by the nearest previously existing crosstie but of magnitude insufficient to propel any pre-existing Bloch line to the position occupied by the last nucleated crosstie, in a positive direction perpendicular to the easy axes of said layer.

Claim 25

Dependent Claim 79 words

In a process of propagating binary information as set forth in claim 19, subsequent to applying said propagation pulse and prior to applying said annihilation pulse, the additional step comprised of applying via said single conductor a magnetic nucleation pulse having a duration less than and an amplitude greater than those of said propagation pulse in a positive direction perpendicular to the centerline of said layer whereby a crosstie-Bloch line pair is nucleated between each existing crosstie-Bloch line pair.

Claim 26

Dependent Claim 113 words

A serially accessible memory element for the storage and propagation of crosstie-Bloch line pairs, comprising: a ferromagnetic strip bordered along each of its edges by a plurality of uniformily oriented denticles arranged in a spaced relation to those denticles bordering the opposite edge, each denticle described by a first chord of length A having a projecting end meeting one end of a second chord of length B and a recessed end potentially intersecting a third chord at the centerline of the strip with an angle θ, the unmet end of the second chord potentially intersecting the third chord at the centerline of the strip with an angle φ, wherein: A·SINE 2θ>B·SINE 2 φ.

Claim 27

Dependent Claim 113 words

A serially accessible memory element for the storage and propagation of crosstie-Bloch line pairs, comprising: a ferromagnetic strip bordered along each of its edges by a plurality of uniformily oriented denticles arranged in a spaced relation to those denticles bordering the opposite edge, each denticle described by a first chord of length A having a projecting end meeting one end of a second chord of length B and a recessed end potentially intersecting a third chord at the centerline of the strip with an angle θ, the unmet end of the second chord potentially intersecting the third chord at the centerline of the strip with an angle φ, wherein: A·SINE 2θ>B·SINE 2 φ.

Claim 28

Dependent Claim 15 words

The memory element set forth in claim 21 further comprised of the centerline being straight.

Claim 29

Dependent Claim 19 words

The memory element set forth in claim 21 further comprised of the third chord being parallel to the centerline.

Claim 30

Dependent Claim 15 words

The memory element set forth in claim 21 further comprised of the centerline being circular.

Claim 31

Dependent Claim 15 words

The memory element set forth in claim 21 further comprised of the centerline being coiled.

Claim 32

Dependent Claim 15 words

The memory element set forth in claim 21 further comprised of the centerline being serpentine.

Claim 33

Dependent Claim 69 words

A serially accessible memory element, comprising: a thin-film ferromagnetic layer of uniform thickness having opposed, symmetrically disposed serriform margins; each margin formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 34

Dependent Claim 69 words

A serially accessible memory element, comprising: a thin-film ferromagnetic layer of uniform thickness having opposed, symmetrically disposed serriform margins; each margin formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 35

Dependent Claim 17 words

The memory element set forth in claim 27, further comprising the margins being symmetric about a centerline.

Claim 36

Dependent Claim 20 words

The memory element set forth in claim 28, further comprising the layer having an easy axis parallel to the centerline.

Claim 37

Dependent Claim 20 words

The memory element set forth in claim 28, further comprising the layer having a hard axis parallel to the centerline.

Claim 38

Dependent Claim 28 words

The memory element set forth in claim 28 further comprising the layer having the centerline parallel to an axis intermediate to an easy axis and a hard axis.

Claim 39

Dependent Claim 16 words

The memory element set forth in claim 27 further comprised of the layer being magnetically isotropic.

Claim 40

Dependent Claim 16 words

The memory element set forth in claim 27 further comprised of the layer being magnetically anisotropic.

Claim 41

Dependent Claim 18 words

The memory element set forth in claim 27 further comprising the margins being eccentrically symmetric about a centerline.

Claim 42

Dependent Claim 13 words

The memory element set forth in claim 34 wherein the centerline is straight.

Claim 43

Dependent Claim 13 words

The memory element set forth in claim 34 wherein the centerline is circular.

Claim 44

Dependent Claim 13 words

The memory element set forth in claim 34 wherein the centerline is coiled.

Claim 45

Dependent Claim 13 words

The memory element set forth in claim 34 wherein the centerline is serpentine.

Claim 46

Dependent Claim 77 words

A serially accessible memory comprising: a ferromagnetic layer of uniform thickness less than one thousand angstrom units and having a pair of opposed, unidirectionally oriented, serriform margins; each margin formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 47

Dependent Claim 77 words

A serially accessible memory comprising: a ferromagnetic layer of uniform thickness less than one thousand angstrom units and having a pair of opposed, unidirectionally oriented, serriform margins; each margin formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 48

Dependent Claim 15 words

The memory set forth in claim 39, further comprised of the layer being magnetically isotropic.

Claim 49

Dependent Claim 15 words

The memory set forth in claim 39, further comprised of the layer being magnetically anisotropic.

Claim 50

Dependent Claim 21 words

The memory set forth in claim 39, further comprised of a pair of opposed margins having a symmetry about a centerline.

Claim 51

Dependent Claim 14 words

The memory set forth in claim 42, further comprised of the symmetry being eccentric.

Claim 52

Dependent Claim 14 words

The memory set forth in claim 42, further comprised of the symmetry being regular.

Claim 53

Dependent Claim 81 words

A serially accessible memory element for storage and propagation of binary information, comprising: an oblongly ferromagnetic layer of uniform thickness having denticulation on opposed margins formed by a plurality of asymmetric denticles unidirectionally oriented along the direction of propagation; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 54

Dependent Claim 81 words

A serially accessible memory element for storage and propagation of binary information, comprising: an oblongly ferromagnetic layer of uniform thickness having denticulation on opposed margins formed by a plurality of asymmetric denticles unidirectionally oriented along the direction of propagation; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 55

Dependent Claim 16 words

The memory element set forth in claim 45 further comprised of the layer being magnetically isotropic.

Claim 56

Dependent Claim 16 words

The memory element set forth in claim 45 further comprised of the layer being magnetically anisotropic.

Claim 57

Dependent Claim 18 words

The memory element set forth in claim 45 further comprised of the denticulation of opposed margins being symmetric.

Claim 58

Dependent Claim 17 words

The memory element set forth in claim 48 further comprised of the denticles in each margin abutting.

Claim 59

Dependent Claim 18 words

The memory element set forth in 49 claim further comprised of the denticles in each margin spaced apart.

Claim 60

Dependent Claim 19 words

The memory element set forth in claim 48 further comprised of the denticulation of opposed margins being eccentrically symmetric.

Claim 61

Dependent Claim 17 words

The memory element set forth in claim 51 further comprised of the denticles in each margin abutting.

Claim 62

Dependent Claim 18 words

The memory element set forth in claim 51 further comprised of the denticles in each margin spaced apart.

Claim 63

Dependent Claim 72 words

A serially accessible binary memory, comprising: a ferromagnetic strip of uniform thickness having unidirectionally oriented denticulation along a pair of opposed margins; the denticulation formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 64

Dependent Claim 72 words

A serially accessible binary memory, comprising: a ferromagnetic strip of uniform thickness having unidirectionally oriented denticulation along a pair of opposed margins; the denticulation formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 65

Dependent Claim 90 words

A serially accessible crosstie memory element, comprising: a magnetically isotropic thin-film ferromagnetic strip of uniform thickness with opposed unidirectionally oriented serriform margins, capable of sustaining a domain wall along its length for the storage and propagation of crosstie--Bloch line pairs; each margin formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 66

Dependent Claim 90 words

A serially accessible crosstie memory element, comprising: a magnetically isotropic thin-film ferromagnetic strip of uniform thickness with opposed unidirectionally oriented serriform margins, capable of sustaining a domain wall along its length for the storage and propagation of crosstie--Bloch line pairs; each margin formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 67

Dependent Claim 15 words

The crosstie memory element set forth in claim 55, further comprising the strip being straight.

Claim 68

Dependent Claim 18 words

The crosstie memory element set forth in claim 55, further comprising the strip having at least one curve.

Claim 69

Dependent Claim 15 words

The crosstie memory element set forth in claim 55, further comprising the strip being circular.

Claim 70

Dependent Claim 15 words

The crosstie memory element set forth in claim 57, further comprising the strip being coiled.

Claim 71

Dependent Claim 15 words

The crosstie memory element set forth in claim 57, further comprising the strip being serpentine.

Claim 72

Dependent Claim 82 words

A crosstie memory element, comprising: a magnetically isotropic, ferromagnetic strip of uniform thickness defining a serially accessible data-track along its length for the storage and propagation of crosstie-Bloch line pairs including opposing margins each formed of a plurality of denticles, each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 73

Dependent Claim 82 words

A crosstie memory element, comprising: a magnetically isotropic, ferromagnetic strip of uniform thickness defining a serially accessible data-track along its length for the storage and propagation of crosstie-Bloch line pairs including opposing margins each formed of a plurality of denticles, each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 74

Dependent Claim 15 words

The crosstie memory element set forth in claim 61, further comprising the strip being straight.

Claim 75

Dependent Claim 18 words

The crosstie memory element set forth in claim 61, further comprising the strip having at least one curve.

Claim 76

Dependent Claim 15 words

The crosstie memory element set forth in claim 63, further comprising the strip being circular.

Claim 77

Dependent Claim 15 words

The crosstie memory element set forth in claim 63, further comprising the strip being coiled.

Claim 78

Dependent Claim 15 words

The crosstie memory element set forth in claim 63, further comprising the strip being serpentine.

Claim 79

Dependent Claim 91 words

A crosstie memory element, comprising: a ferromagnetic layer of uniform thickness not greater than one thousand angstrom units, having opposed, unidirectionally oriented, serriform margins defining a serially accessible data-track along its length for the storage and propagation of crosstie-Bloch line pairs; each margin formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 80

Dependent Claim 91 words

A crosstie memory element, comprising: a ferromagnetic layer of uniform thickness not greater than one thousand angstrom units, having opposed, unidirectionally oriented, serriform margins defining a serially accessible data-track along its length for the storage and propagation of crosstie-Bloch line pairs; each margin formed by a plurality of denticles; each denticle having a major edge intersecting a minor edge wherein for each denticle the projected length of its major edge upon an imaginary centerline disposed between the opposed margins exceeds the projected length of its minor edge upon the same centerline.

Claim 81

Dependent Claim 18 words

The crosstie memory element set forth in claim 67, further comprising the layer having at least one curve.

Claim 82

Dependent Claim 15 words

The crosstie memory element set forth in claim 68, further comprising the layer being coiled.

Claim 83

Dependent Claim 15 words

The crosstie memory element set forth in claim 68, further comprising the layer being serpentine.

Claim 84

Dependent Claim 15 words

The crosstie memory element set forth in claim 68, further comprising the layer being circular.

Claim 85

Dependent Claim 16 words

The crosstie memory element set forth in claim 67, further comprising the layer being magnetically isotropic.

Claim 86

Dependent Claim 19 words

The crosstie memory element set forth in claim 67, further comprising the layer having regular, symmetrically disposed serriform edges.

Claim 87

Dependent Claim 18 words

The crosstie memory element set forth in claim 67, further comprising the layer having unidirectionally oriented serriform edges.

Claim 88

Dependent Claim 27 words

The memory set forth in claims 27, 39, 45 or 54 further comprising the ferromagnetic layer supporting the propagation of Bloch line--crosstie pairs between the opposed margins.

Claim 89

Dependent Claim 20 words

The memory set forth in claims 27, 39, 45 or 54 further comprising the ferromagnetic layer being a unitary component.

Claim 90

Dependent Claim 67 words

The memory set forth in claims 27, 39, 45, 54, 55, or 67, comprising each denticle having a first outside edge of length A intersecting a second outside edge of length B, the first edge potentially forming an angle θ with an imaginary centerline disposed between the opposed margins, and the second edge potentially forming an angle φ with said centerline, wherein: A SINE 2θ>B SINE 2θ.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1983-10-28	1984-04-28	1984-10-28	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1987-10-28	1988-04-28	1988-10-28	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1991-10-28	1992-04-28	1992-10-28	$7700.00	Window Closed / Lapsed

Serriform strip crosstie memory

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