US3727002A
Expired / Lapsed
US
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Magnetic method for digitally identifying the location of an applied force
Assignee: Potter Instrument Co Inc
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Filing: 1971-03-29
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Granted: 1973-04-10
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Expires: 1991-03-29
Abstract
Abstract A method and apparatus for digitally identifying the location of an applied force by utilizing the changes in the properties of a magnetic material in response to the application of a force to the material. In one embodiment, a matrix of similarly-oriented magnetic cores is arranged so that the rows and columns of cores are sequentially driven by a driving signal from a core driver circuit. Sense lines are provided for both the rows and the columns of cores and are arranged so that the row sense lines thread a like number of cores in each row in each of a first direction and a second or opposite direction. The column sense lines are also located so that a like number of cores in each column are threaded in each of a first direction and a second direction. In the absence of a force applied to any one of the cores, the resultant sensed output from the column sense lines as the rows of cores are sequentially driven is substantially zero, since the sensed output produced by the cores threaded by the sense lines in one direction is cancelled by the sensed output produced by the cores threaded by the sense lines in a second direction. When a force is applied to a core, a signal is sensed by the column sense lines during the sequential driving of the rows of cores which cause a control circuit to actuate a counter to indicate the X-coordinate of the location of the force. Similarly, when the columns of cores are being driven, a signal is sensed by the row sense line during the sequential driving of the columns of cores which causes the control circuit to indicate a count on a Y-counter to indicate the Y-coordinate of the force. The respective coordinates thus indicate the location of the force. In an alternative embodiment, the column drive lines are used as sensing lines when the rows of cores are being sequentially driven, while the row drive lines are used as the sense lines when the columns of cores are sequentially driven. Circuit modifications to effect a reduction in the number of leads threading each core for the alternative embodiment are thus disclosed.
Inventors
- 👤 C Pear
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:22
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/94; H03K17/965; H03K17/97; H03K17/972
Claims Analysis
Total Claims: 52
Claim 1
Independent Claim
147 words
An apparatus for indicating the location of an applied force comprising the combination of: a ferromagnetic core which exhibits a change in a sensed output signal responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core, means for sensing the change in the sensed output signal including circuit means in combination with said core which provide a neutralizing signal substantially equal in magnitude to the sensed signal produced by said core when influenced by a first force, and indicating means responsive to said sensing means to indicate that force has been applied to indicate the location of said force, said circuit means being arranged so that said indicating means is responsive to a sensed output signal from said core when a second force which is different from said first force is applied to said core.
Claim 2
Independent Claim
147 words
An apparatus for indicating the location of an applied force comprising the combination of: a ferromagnetic core which exhibits a change in a sensed output signal responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core, means for sensing the change in the sensed output signal including circuit means in combination with said core which provide a neutralizing signal substantially equal in magnitude to the sensed signal produced by said core when influenced by a first force, and indicating means responsive to said sensing means to indicate that force has been applied to indicate the location of said force, said circuit means being arranged so that said indicating means is responsive to a sensed output signal from said core when a second force which is different from said first force is applied to said core.
Claim 3
Dependent Claim
58 words
The apparatus as set forth in claim 1 wherein said indicating means is responsive to the difference between the sensed output signal from said core when said core is influenced by said second force and the signal representing the difference between the sensed output signal from said core when influenced by said first force and said neutralizing signal.
Claim 4
Dependent Claim
105 words
The apparatus as set forth in claim 2 wherein said apparatus includes a second core which exhibits a change in a sensed output signal responsive to a drive signal applied to said second core wherein said change is a function of a force applied to said second core, said second core being arranged so that said second core when influenced by a force substantially equal to said first force produces a sensed output signal in response to a drive signal applied to said core which is substantially equal in magnitude to the sensed output signal from said first core when influenced by said first force.
Claim 5
Dependent Claim
22 words
The apparatus as set forth in claim 3 whErein said indicating means includes means for digitally coding the location of said force.
Claim 6
Dependent Claim
25 words
The apparatus as set forth in claim 3 wherein said second force is produced by a stylus which exerts a force on said first core.
Claim 7
Independent Claim
186 words
An apparatus for indicating the locations of an applied force comprising the combination of: a matrix of magnetic cores arranged in rows and columns of said cores wherein each of said cores exhibits a change in the sensed output signal from a core responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core, means for driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, means for sensing the output signal of the cores in said matrix, the sensed output signal being responsive to said drive signal, the net output signal sensed by said sensing means from the selected ones of said cores which are driven by a drive signal from said drive means being substantially zero when each of said elected ones of said cores is subjected to substantially the same force, and indicating means responsive to said sensing means to indicate that a force has been applied to at least one of said cores in said matrix and to indicate the location of said force.
Claim 8
Independent Claim
186 words
An apparatus for indicating the locations of an applied force comprising the combination of: a matrix of magnetic cores arranged in rows and columns of said cores wherein each of said cores exhibits a change in the sensed output signal from a core responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core, means for driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, means for sensing the output signal of the cores in said matrix, the sensed output signal being responsive to said drive signal, the net output signal sensed by said sensing means from the selected ones of said cores which are driven by a drive signal from said drive means being substantially zero when each of said elected ones of said cores is subjected to substantially the same force, and indicating means responsive to said sensing means to indicate that a force has been applied to at least one of said cores in said matrix and to indicate the location of said force.
Claim 9
Independent Claim
196 words
An apparatus for indicating the location of an applied force comprising the combination of: a matrix of magnetic cores arranged in rows and columns of said cores wherein each of said cores exhibits a change in a sensed output signal from a core responsive to a drive signal applied to said core wherein said change in a function of a force applied to said core, means for driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, means for sensing the output signal of the cores in said matrix, the sensed output signal being responsive to said drive signal, a net output signal being sensed by said sensing means from the selected ones of said cores which are driven by a drive signal from said drive means when at least one of the cores is subjected to a force different from the force applied to the remaining cores of said selected ones of said cores, and indicating means responsive to said sensing means to indicate that a force has been applied to at least one of said cores in said matrix and to indicate the location of said cores.
Claim 10
Independent Claim
196 words
An apparatus for indicating the location of an applied force comprising the combination of: a matrix of magnetic cores arranged in rows and columns of said cores wherein each of said cores exhibits a change in a sensed output signal from a core responsive to a drive signal applied to said core wherein said change in a function of a force applied to said core, means for driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, means for sensing the output signal of the cores in said matrix, the sensed output signal being responsive to said drive signal, a net output signal being sensed by said sensing means from the selected ones of said cores which are driven by a drive signal from said drive means when at least one of the cores is subjected to a force different from the force applied to the remaining cores of said selected ones of said cores, and indicating means responsive to said sensing means to indicate that a force has been applied to at least one of said cores in said matrix and to indicate the location of said cores.
Claim 11
Independent Claim
196 words
An apparatus for indicating the location of an applied force comprising the combination of: a matrix of magnetic cores arranged in rows and columns of said cores wherein each of said cores exhibits a change in a sensed output signal from a core responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core, means for driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, means for sensing the output signal of the cores in said matrix, the sensed output signal being responsive to said drive signal, a net output signal being sensed by said sensing means from the selected ones of said cores which are driven by a drive signal from said drive means when at least one of the cores is subjected to a force different from the force applied to the remaining cores of said selected ones of said cores, and indicating means responsive to said sensing means to indicate that a force has been applied to at least one of said cores in said matrix and to indicate the location of said cores.
Claim 12
Independent Claim
196 words
An apparatus for indicating the location of an applied force comprising the combination of: a matrix of magnetic cores arranged in rows and columns of said cores wherein each of said cores exhibits a change in a sensed output signal from a core responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core, means for driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, means for sensing the output signal of the cores in said matrix, the sensed output signal being responsive to said drive signal, a net output signal being sensed by said sensing means from the selected ones of said cores which are driven by a drive signal from said drive means when at least one of the cores is subjected to a force different from the force applied to the remaining cores of said selected ones of said cores, and indicating means responsive to said sensing means to indicate that a force has been applied to at least one of said cores in said matrix and to indicate the location of said cores.
Claim 13
Dependent Claim
27 words
The apparatus as set forth in claim 7 wherein said driving means sequentially drives each of a plurality of selected ones of said cores in said matrix.
Claim 14
Dependent Claim
27 words
The apparatus as set forth in claim 7 wherein said driving means sequentially drives each of a plurality of selected ones of said cores in said matrix.
Claim 15
Dependent Claim
52 words
The apparatus as set forth in claim 8 wherein said indicating means is responsive to said net output signal to indicate that one of said selected cores in said plurality of selected ones of said cores is influenced by a force different from the force applied to others of the driven cores.
Claim 16
Dependent Claim
52 words
The apparatus as set forth in claim 8 wherein said indicating means is responsive to said net output signal to indicate that one of said selected cores in said plurality of selected ones of said cores is influenced by a force different from the force applied to others of said driven cores.
Claim 17
Dependent Claim
29 words
The apparatus as set forth in claim 9 wherein said indicating means digitally codes the location of a core in said matrix which is influenced by said difference force.
Claim 18
Dependent Claim
29 words
The apparatus as set forth in claim 8 wherein said indicating means digitally codes the location of a core in said matrix which is influenced by said different force.
Claim 19
Dependent Claim
40 words
The apparatus as set forth in claim 9 wherein said driving means for a first plurality of selected ones of said cores comprises a portion of said sensing means for a second plurality of said selected ones of said cores.
Claim 20
Dependent Claim
40 words
The apparatus as set forth in claim 9 wherein said driving means for a first plurality of selected ones of said cores comprises a portion of said sensing means for a second plurality of said selected ones of said cores.
Claim 21
Dependent Claim
55 words
The apparatus as set forth in claim 11 wherein said matrix comprises a plurality of rows of cores and a plurality of columns of said cores and wherein the means for driving a row of cores serves as a portion of the means for sensing the sensed output from a column of cores when driven.
Claim 22
Dependent Claim
55 words
The apparatus as set forth in claim 11 wherein said matrix comprises a plurality of rows of cores and a plurality of columns of said cores and wherein the means for driving a row of cores serves as a portion of the means for sensing the sensed output from a column of cores when driven.
Claim 23
Independent Claim
123 words
A method for locating an applied force on a magnetic material which exhibits a change in the sensed output signal responsive to a drive signal applied to said magnetic material wherein said change is a function of a force applied to said magnetic material comprising the steps of: sensing the change in the sensed output signal; providing a neutralizing signal substantially equal in magnitude to the sensed output signal produced by said core by a first force; and indicating both that a force has been applied to the magnetic material and the location of the force by responding to a sensed output signal from said core when a second force which is different from said first force is applied to said magnetic material.
Claim 24
Independent Claim
123 words
A method for locating an applied force on a magnetic material which exhibits a change in the sensed output signal responsive to a drive signal applied to said magnetic material wherein said change is a function of a force applied to said magnetic material comprising the steps of: sensing the change in the sensed output signal; providing a neutralizing signal substantially equal in magnitude to the sensed output signal produced by said core by a first force; and indicating both that a force has been applied to the magnetic material and the location of the force by responding to a sensed output signal from said core when a second force which is different from said first force is applied to said magnetic material.
Claim 25
Independent Claim
123 words
A method for locating an applied force on a magnetic material which exhibits a change in the sensed output signal responsive to a drive signal applied to said magnetic material wherein said change is a function of a force applied to said magnetic material comprising the steps of: sensing the change in the sensed output signal; providing a neutralizing signal substantially equal in magnitude to the sensed output signal produced by said core by a first force; and indicating both That a force has been applied to the magnetic material and the location of the force by responding to a second output signal from said core when a second force which is different from said first force is applied to said magnetic material.
Claim 26
Independent Claim
123 words
A method for locating an applied force on a magnetic material which exhibits a change in the sensed output signal responsive to a drive signal applied to said magnetic material wherein said change is a function of a force applied to said magnetic material comprising the steps of: sensing the change in the sensed output signal; providing a neutralizing signal substantially equal in magnitude to the sensed output signal produced by said core by a first force; and indicating both That a force has been applied to the magnetic material and the location of the force by responding to a second output signal from said core when a second force which is different from said first force is applied to said magnetic material.
Claim 27
Dependent Claim
63 words
The method as set forth in claim 13 wherein the step of providing a neutralizing signal is further defined in that said neutralizing signal is provided from a second core which exhibits a change in a sensed output signal responsive to a drive signal applied to said second core wherein said change is a function of a force applied to said second core.
Claim 28
Dependent Claim
63 words
The method as set forth in claim 13 wherein the step of providing a neutralizing signal is further defined in that said neutralizing signal is provided from a second core which exhibits a change in a sensed output signal responsive to a drive signal applied to said second core wherein said change is a function of a force applied to said second core.
Claim 29
Dependent Claim
21 words
The method as set forth in claim 14 wherein the step of indicating includes the step of digitally locating said force.
Claim 30
Dependent Claim
21 words
The method as set forth in claim 14 wherein the step of indicating includes the step of digitally locating said force.
Claim 31
Independent Claim
154 words
The method for indicating the location os a force on a matrix of magnetic cores arranged in rows and columns wherein each of said cores exhibits a change in the sensed output signal from a core responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core comprising the steps of: driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, sensing the output signal from the selected ones of said cores in said matrix which are driven by a drive signal when at least one of the cores is subjected to a force different from the force applied to the remaining cores of said selected ones of said cores, and indicating that a force has been applied to at least one of said cores in said matrix and to indicate the location of said force.
Claim 32
Independent Claim
154 words
The method for indicating the location os a force on a matrix of magnetic cores arranged in rows and columns wherein each of said cores exhibits a change in the sensed output signal from a core responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core comprising the steps of: driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, sensing the output signal from the selected ones of said cores in said matrix which are driven by a drive signal when at least one of the cores is subjected to a force different from the force applied to the remaining cores of said selected ones of said cores, and indicating that a force has been applied to at least one of said cores in said matrix and to indicate the location of said force.
Claim 33
Independent Claim
154 words
The method for indicating the location of a force on a matrix of magnetic cores arranged in rows and columns wherein each of said cores exhibits a change in the sensed output signal from a core responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core comprising the steps of: driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, sensing the output signal from the selected ones of said cores in said matrix which are driven by a drive signal when at least one of the cores is subjected to a force different from the force applied to the remaining cores of said selected ones of said cores, and indicating that a force has been applied to at least one of said cores in said matrix and to indicate the location of said force.
Claim 34
Independent Claim
154 words
The method for indicating the location of a force on a matrix of magnetic cores arranged in rows and columns wherein each of said cores exhibits a change in the sensed output signal from a core responsive to a drive signal applied to said core wherein said change is a function of a force applied to said core comprising the steps of: driving selected ones of the cores in said matrix in a predetermined sequence with a drive signal, sensing the output signal from the selected ones of said cores in said matrix which are driven by a drive signal when at least one of the cores is subjected to a force different from the force applied to the remaining cores of said selected ones of said cores, and indicating that a force has been applied to at least one of said cores in said matrix and to indicate the location of said force.
Claim 35
Dependent Claim
32 words
The method as set forth in claim 16 wherein the step of driving includes the step of sequentially driving each of a plurality of selected ones of said cores in said matrix.
Claim 36
Dependent Claim
32 words
The method as set forth in claim 16 wherein the step of driving includes the step of sequentially driving each of a plurality of selected ones of said cores in said matrix.
Claim 37
Dependent Claim
56 words
The method as set forth in claim 17 wherein the step of indicating includes the step of responding to said net output signal by indicating that one of said selected cores in said plurality of selected ones of said cores is influenced by a force different from the force applied to others of the driven core.
Claim 38
Dependent Claim
56 words
The method as set forth in claim 17 wherein the step of indicating includes the step of responding to said net output signal by indicating that one of said selected cores in said plurality of selected ones of said cores is influenced by a force different from the force applied to others of the driven core.
Claim 39
Dependent Claim
34 words
The method as set forth in claim 18 wherein the step of indicating includes the step of digitally coding the location of a core in said matrix which is influenced by said different force.
Claim 40
Dependent Claim
34 words
The method as set forth in claim 18 wherein the step of indicating includes the step of digitally coding the location of a core in said matrix which is influenced by said different force.
Claim 41
Dependent Claim
44 words
The method as set forth in claim 19 wherein the step of driving includes the step of selecting ones of said cores to comprise a portion of said sensing means for a second plurality of said selected ones of said cores which are driven.
Claim 42
Dependent Claim
44 words
The method as set forth in claim 19, wherein the step of driving includes the step of selecting ones of said cores to comprise a portion of said sensing means for a second plurality of said selected ones of said cores which are driven.
Claim 43
Dependent Claim
59 words
The method as set forth in claim 20 wherein the matrix comprises a plurality of rows of cores and a plurality of columns of said cores and wherein the step of driving includes the step of using a row of cores as a portion of the apparatus which senses the sensed output from a column of cores when driven.
Claim 44
Dependent Claim
59 words
The method as set forth in claim 20 wherein the matrix comprises a plurality of rows of cores and a plurality of columns of said cores and wherein the step of driving includes the step of using a row of cores as a portion of the apparatus which senses the sensed output from a column of cores when driven.
Claim 45
Dependent Claim
153 words
Apparatus for indicating the location of an applied force comprising the combination of: a matrix of ferro-magnetic cores arranged in rows and columns, each core exhibiting an analog change in magnetic properties in accordance with the magnitude of a force applied to said core; means for providing a sensed output from each individual core, said sensed output varying in accordance with said magnetic properties of the corresponding core; matrix circuit means for providing coordinate outputs corresponding respectively to rows and columns of said cores, said circuit means being arranged such that the output for each row or each column represents the difference between the combined outputs of two sets of cores in the corresponding row or column and, when the forces applied to said sets of cores are balanced, said coordinate output is in a null condition; and means responsive to said coordinate outputs for digitally indicating the location of said applied force.
Claim 46
Dependent Claim
153 words
Apparatus for indicating the location of an applied force comprising the combination of: a matrix of ferro-magnetic cores arranged in rows and columns, each core exhibiting an analog change in magnetic properties in accordance with the magnitude of a force applied to said core; means for providing a sensed output from each individual core, said sensed output varying in accordance with said magnetic properties of the corresponding core; matrix circuit means for providing coordinate outputs corresponding respectively to rows and columns of said cores, said circuit means being arranged such that the output for each row or each column represents the difference between the combined outputs of two sets of cores in the corresponding row or column and, when the forces applied to said sets of cores are balanced, said coordinate output is in a null condition; and means responsive to said coordinate outputs for digitally indicating the location of said applied force.
Claim 47
Dependent Claim
153 words
Apparatus for indicating the location of an applied force comprising the combination of: a matrix of ferro-magnetic cores arranged in rows and columns, each core exhibiting an analog change in magnetic properties in accordance with the magnitude of a force applied to said core; means for providing a sensed output from each individual core, said sensed output varying in accordance with said magnetic properties of the corresponding core; matrix circuit means for providing coordinate outputs corresponding respectively to rows and columns of said cores, said circuit means being arranged such that the output for each row or each column represents the difference between the combined outputs of two sets of cores in the corresponding row or column and, when the forces applied to said sets of cores are balanced, said coordinate output is in a null condition; and means responsive to said coordinate outputs for digitally indicating the location of said applied force.
Claim 48
Dependent Claim
153 words
Apparatus for indicating the location of an applied force comprising the combination of: a matrix of ferro-magnetic cores arranged in rows and columns, each core exhibiting an analog change in magnetic properties in accordance with the magnitude of a force applied to said core; means for providing a sensed output from each individual core, said sensed output varying in accordance with said magnetic properties of the corresponding core; matrix circuit means for providing coordinate outputs corresponding respectively to rows and columns of said cores, said circuit means being arranged such that the output for each row or each column represents the difference between the combined outputs of two sets of cores in the corresponding row or column and, when the forces applied to said sets of cores are balanced, said coordinate output is in a null condition; and means responsive to said coordinate outputs for digitally indicating the location of said applied force.
Claim 49
Dependent Claim
187 words
Apparatus for indicating the location of an applied force comprising the combination of: a matrix of pressure-responsive ferro-magnetic cores arranged in columns and rows, said matrix being divided into four sections by first and second intersecting reference lines; means for providing a sensed output from each core, said sensed output being responsive in an analog fashion to the application of force to the corresponding core; matrix circuit means for providing coordinate analog outputs corresponding respectively to rows anD columns of said cores, said circuit means being arranged such that the output for each row represents the difference between the combined sensed outputs from cores lying on opposite sides of said first reference line, and the output for each column represents the difference between the combined sensed outputs from cores lying on opposite sides of said second reference line, and, when the forces applied to said cores in a row or column are balanced on either side of said first or second reference line respectively, said coordinate output is in a null operation; and means responsive to said coordinate outputs for indicating the location of said applied force.
Claim 50
Dependent Claim
187 words
Apparatus for indicating the location of an applied force comprising the combination of: a matrix of pressure-responsive ferro-magnetic cores arranged in columns and rows, said matrix being divided into four sections by first and second intersecting reference lines; means for providing a sensed output from each core, said sensed output being responsive in an analog fashion to the application of force to the corresponding core; matrix circuit means for providing coordinate analog outputs corresponding respectively to rows anD columns of said cores, said circuit means being arranged such that the output for each row represents the difference between the combined sensed outputs from cores lying on opposite sides of said first reference line, and the output for each column represents the difference between the combined sensed outputs from cores lying on opposite sides of said second reference line, and, when the forces applied to said cores in a row or column are balanced on either side of said first or second reference line respectively, said coordinate output is in a null operation; and means responsive to said coordinate outputs for indicating the location of said applied force.
Claim 51
Dependent Claim
187 words
Apparatus for indicating the location of an applied force comprising the combination of: a matrix of pressure-responsive ferro-magnetic cores arranged in columns and rows, said matrix being divided into four sections by first and second intersecting reference lines; means for providing a sensed output from each core, said sensed output being responsive in an analog fashion to the application of force to the corresponding core; matrix circuit means for providing coordinate analog outputs corresponding respectively to rows and columns of said cores, said circuit means being arranged such that the output for each row represents the difference between the combined sensed outputs from cores lying on opposite sides of said first reference line, and the output for each column represents the difference between the combined sensed outputs from cores lying on opposite sides of said second reference line, and, when the forces applied to said cores in a row or column are balanced on either side of said first or second reference line respectively, said coordinate output is in a null condition; and means responsive to said coordinate outputs for indicating the location of said applied force.
Claim 52
Dependent Claim
187 words
Apparatus for indicating the location of an applied force comprising the combination of: a matrix of pressure-responsive ferro-magnetic cores arranged in columns and rows, said matrix being divided into four sections by first and second intersecting reference lines; means for providing a sensed output from each core, said sensed output being responsive in an analog fashion to the application of force to the corresponding core; matrix circuit means for providing coordinate analog outputs corresponding respectively to rows and columns of said cores, said circuit means being arranged such that the output for each row represents the difference between the combined sensed outputs from cores lying on opposite sides of said first reference line, and the output for each column represents the difference between the combined sensed outputs from cores lying on opposite sides of said second reference line, and, when the forces applied to said cores in a row or column are balanced on either side of said first or second reference line respectively, said coordinate output is in a null condition; and means responsive to said coordinate outputs for indicating the location of said applied force.
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| 11.5 Years (Year 12) | 1984-04-09 | 1984-10-09 | 1985-04-10 | $7700.00 | Window Closed / Lapsed |