Patent US3577050A successfully refreshed from Google Patents.
US3577050A
Expired / Lapsed
US
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Vehicle driven by synchronous motors
Assignee: Allis Chalmers Corp
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Filing: 1969-08-27
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Granted: 1971-05-04
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Expires: 1989-08-27
Abstract
Abstract The wheels of a vehicle are driven by inductor type synchronous motors having solid rotors without windings and commutators. A diesel on the vehicle drives a pair of high frequency rotating generators each of which supplies power to a pair of the synchronous motors. Power pedal means actuated by the operator derive a power signal proportional to the desired tractive effort for the vehicle. A separate electric drive for each motor includes means for deriving a control signal modulated at motor speed, a cycloconverter between each motor and its generator regulated by the control signal, tachometer means for deriving a speed signal which is a function of motor speed, and control means responsive to both the power signal and speed signal for regulating the magnitude and phase of the control signal so that the motor output power is constant over the speed range at a level in accordance with the power pedal setting. Brake means actuated by the operator derive a brake signal, and the vehicle has means for shifting the phase of the control signals for all the motors to regeneratively brake them when the brake signal exceeds the power signal. The vehicle has travel direction selector means for shifting the phase of all the control signals to reverse the direction of motor rotation and thus propel the vehicle backward. The vehicle has manually operated means for setting a speed limit for the vehicle and means for deriving a speed limit signal which is additive to the brake signal to regeneratively brake the motors when vehicle speed exceeds the set speed limit. Turn compensation means increase the power supplied to the motors of the wheels on the outside of a turn and decrease the power supplied to the motors of the wheels on the inside of the turn as a function of the degree of turn and the magnitude of the power signal.
Inventors
- 👤 William L Ringland
- 👤 Manfred E Neumann
- 👤 Ernst K Kaeser
- 👤 Thomas P Gilmore
- 👤 Allois F Geiersbach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:45
CPC Classifications
B; B60; B60K; B60K17/00; B60K1/00; B60K17/34; B60K17/356; B60L; B60L15/00; B60L15/007; B60L15/02; B60L15/025; B60L3/00; B60L3/0023; B60L3/003; B60L50/00; B60L50/50; B60L50/60; B60L50/61; B60L7/00; B60L7/10; B60L7/14; B60L7/18; H; H02; H02K; H02K19/00; H02K19/02; H02K19/10; H02K19/103; B60L2210/00; B60L2210/30; B60L2210/40; B60L2220/00; B60L2220/10; B60L2220/14; B60L2220/40; B60L2220/44; B60L2220/46; B60L2240/00; B60L2240/10; B60L2240/12; B60L2240/40; B60L2240/42; B60L2240/421; B60L2240/423; B60L2240/427; B60L2240/52; B60L2240/525; B60L2250/00; B60L2250/26; B60L2260/00; B60L2260/20; B60L2260/28; F; F02; F02B; F02B3/00; F02B3/06; Y; Y02; Y02T; Y02T10/00; Y02T10/60; Y02T10/62; Y02T10/64; Y02T10/70; Y02T10/7072; Y02T10/72
Claims Analysis
Total Claims: 61
Claim 1
Independent Claim
111 words
In combination, a land vehicle having a ground-engaging tractive element, at least one inductor type synchronous motor on said vehicle having a polyphase stator winding, a rotor operatively connected to said tractive element, and means for generating magnetic poles in said rotor, a prime mover on said vehicle, a polyphase alternator on said vehicle driven by said prime mover, means operatively connected to said rotor for generating an output signal having a frequency which is a function of the speed of said motor, a polyphase frequency converter between said alternator and said stator winding controlled by said output signal, and control means for selectively varying a condition of said output signal.
Claim 2
Dependent Claim
111 words
In combination, a land vehicle having a ground-engaging tractive element, at least one inductor type synchronous motor on said vehicle having a polyphase stator winding, a rotor operatively connected to said tractive element, and means for generating magnetic poles in said rotor, a prime mover on said vehicle, a polyphase alternator on said vehicle driven by said prime mover, means operatively connected to said rotor for generating an output signal having a frequency which is a function of the speed of said motor, a polyphase frequency converter between said alternator and said stator winding controlled by said output signal, and control means for selectively varying a condition of said output signal.
Claim 3
Dependent Claim
33 words
In the combination of claim 1 wherein said rotor is solid and ferromagnetic and said means for generating magnetic poles in said rotor includes a field winding on the stator of said motor.
Claim 4
Dependent Claim
37 words
In the combination of claim 2 wherein said output signal generating means derives a polyphase output signal, and said frequency converter is a cycloconverter having controlled rectifiers between each phase of said stator winding and said alternator.
Claim 5
Dependent Claim
58 words
In the combination of claim 3 wherein said control means includes means for deriving reference signals which are functions of the phase voltages generated by said alternator, means for combining said reference signals and the phase output signals to provide composite sequence signals, and means controlled by said sequence signals for deriving gating signals for said controlled rectifiers.
Claim 6
Dependent Claim
75 words
In the combination of claim 4 wherein said gating signal deriving means includes means for detecting when said sequence signals cross the zero axis and wherein the maximum frequency of said output signal over the speed range of said motor is F cycles per second, and including governor means for controlling the speed of said prime mover so that said alternator generates a polyphase voltage having a frequency of at least 2F cycles per second.
Claim 7
Dependent Claim
54 words
In the combination of claim 5 and including means for selectively deriving a power signal which is a function of the desired tractive effort of said vehicle and whereIn said control means is responsive to said power signal and varies a condition of said polyphase output signal as a function of said power signal.
Claim 8
Dependent Claim
51 words
In the combination of claim 6 and including tachometer means for deriving a speed signal which is a function of the speed of said motor and wherein said control means regulates the magnitude and shifts the phase of said output signal in accordance with said power signal and said speed signal.
Claim 9
Dependent Claim
86 words
In the combination of claim 7 and including manually operated means for selectively driving a brake signal, and wherein said control means includes a subtractive amplifier for comparing said power and brake signals and generating a difference signal which is a function of their difference, and wherein said control means regulates the magnitude and shifts the phase of said polyphase output signal in accordance with said difference signal and said speed signal and regulates the energization of said field winding in accordance with said difference signal.
Claim 10
Dependent Claim
124 words
In the combination of claim 8 wherein said subtractive amplifier provides a difference signal of one polarity when said brake signal is greater than said power signal and of the opposite polarity when said power signal is greater than said brake signal and wherein said control means includes absolute value amplifier means responsive to either polarity of said difference signal for providing an absolute value signal whose magnitude is a function of the magnitude of said difference signal, and wherein said control means regulates the magnitude and shifts the phase of said polyphase output signal as a function of said absolute value signal and said speed signal and also controls the energization of said field winding as a function of said absolute value signal.
Claim 11
Dependent Claim
40 words
In the combination of claim 9 wherein said control means includes brake sense means responsive to said one polarity of said difference signal for shifting the phase of said polyphase output signal 180* to effect regenerative braking of said motor.
Claim 12
Dependent Claim
62 words
In the combination of claim 10 wherein said control means includes vector adder inductor means having a pair of energizing windings and a secondary winding inductively linked to said energizing windings and in which said output signal is induced and said brake sense means includes means for reversing both of said energizing windings to shift the phase of said output signal 180*.
Claim 13
Dependent Claim
42 words
In the combination of claim 9 and including manually operated travel direction selector means for shifting the phase of said polyphase output signal to effect reversal of the direction of rotation of said motor and the direction of travel of said vehicle.
Claim 14
Dependent Claim
62 words
In the combination of claim 12 wherein said control means includes vector adder inductor means having a pair of energizing windings and a secondary winding inductively linked to said energizing windings and in which said output signal is induced and said travel direction selector means includes means to reverse one of said energizing windings to shift the phase of said output signal.
Claim 15
Dependent Claim
99 words
In the combination of claim 9 and including protective means responsive to an undesirable operating condition in said vehicle for deriving a fault signal, and wherein said control means includes summing amplifier means receiving said absolute value signal and said fault signal as inputs and providing a summing signal which is a function of their sum, and wherein said control means regulates the magnitude and shifts the phase of said polyphase output signal as a function of said summing signal and said speed signal and controls the energization of said field winding as a function of said summing signal.
Claim 16
Dependent Claim
75 words
In the combination of claim 8 and including means for selectively deriving a speed limit signal which is a function of the desired maximum speed of said vehicle, speed limit means for comparing said speed signal and said speed limit signal and for deriving a speed limit error signal when the former exceeds the latter, said sPeed limit error signal being an input to said subtractive amplifier and being additive to said brake signal input.
Claim 17
Dependent Claim
39 words
In the combination defined by claim 2 and including means for selectively deriving a power signal which is a function of the desired tractive effort of said vehicle and wherein said control means is responsive to said power signal.
Claim 18
Dependent Claim
51 words
In the combination of claim 16 and including tachometer means for deriving a speed signal which is a function of the speed of said motor and wherein said control means regulates the magnitude and shifts the phase of said output signal in accordance with said power signal and said speed signal.
Claim 19
Dependent Claim
74 words
In the combination of claim 16 and including manually controlled means for selectively deriving a brake signal, and wherein said control means includes a subtractive amplifier for comparing said power and said brake signals and for generating a difference signal which is a function of their difference, and wherein said control means varies a condition of said output signal and regulates the energization of said field winding as a function of said difference signal.
Claim 20
Dependent Claim
114 words
In the combination of claim 18 wherein said subtractive amplifier provides a difference signal of one polarity when said brake signal is greater than said power signal and of the opposite polarity when said power signal is greater than said brake signal and wherein said control means includes absolute value amplifier means responsive to either polarity of said difference signal for providing an absolute value signal whose magnitude is a function of the magnitude of said difference signal, said control means varying a condition of said output signal as a function of said absolute value signal and also regulating the voltage applied to said field winding as a function of said absolute value signal.
Claim 21
Dependent Claim
29 words
In the combination of claim 19 wherein said control means includes brake sense means responsive to said one polarity of said difference signal for regeneratively braking said synchronous motor.
Claim 22
Dependent Claim
39 words
In the combination of claim 18 wherein said control means includes brake sense means responsive to said one polarity of said difference signal for shifting the phase of said output signal 180* to effect regenerative braking of said motor.
Claim 23
Dependent Claim
62 words
In the combination of claim 21 wherein said control means includes vector adder inductor means having a pair of energizing windings and a secondary winding inductively linked to said energizing windings and in which said output signal is induced and said brake sense means includes means for reversing both of said energizing windings to shift the phase of said output signal 180*.
Claim 24
Dependent Claim
48 words
In the combination of claim 3 and including manually operable travel direction selector means for shifting the phase of the voltage supplied by said cycloconverter to said stator winding to reverse the direction of rotation of said motor and thereby reverse the direction of travel of said vehicle.
Claim 25
Dependent Claim
62 words
In the combination of claim 23 wherein said control means includes vector adder inductor means having a pair of energizing windings and a secondary winding inductively linked to said energizing windings and in which said output signal is induced and said travel direction selector means includes means for reversing one of said energizing windings to shift the phase of said output signal.
Claim 26
Dependent Claim
81 words
In the combination of claim 19 and including protective means responsive to an undesirable operating condition in said vehicle for deriving a fault signal and wherein said control means includes a summing amplifier means receiving said absolute value and fault signals as inputs and providing a summing signal which is a function of their sum and said control means varies a condition of said output signal and controls the energization of said field winding as a function of said summing signal.
Claim 27
Dependent Claim
93 words
In the combination of claim 18 and including manually operated means for deriving a speed limit signal whose magnitude is proportional to the Desired maximum speed of said vehicle, tachometer means for generating a speed signal which is a function of the speed of said motor, speed limit means for comparing said speed signal and said speed limit signal and for deriving a speed limit error signal when the former exceeds the latter, said speed limit error signal being an input to said subtractive amplifier and being additive with said brake signal input.
Claim 28
Dependent Claim
138 words
In combination, a land vehicle having an earth-engaging tractive element, at least one synchronous electric motor on said vehicle having a stator winding and a rotor operatively connected to said tractive element, a prime mover on said vehicle, electric generator means including an alternator on said vehicle driven by said prime mover, means on said vehicle for selectively deriving a power signal which is a function of the desired tractive effort of said vehicle, manually controlled means for selectively deriving a brake signal, subtractive amplifier means for comparing said power and brake signals and for generating a difference signal which is a function of their difference, and control means between said electric generator means and said stator winding for regulating the voltage delivered by said generator means to said stator winding as a function of said difference signal.
Claim 29
Dependent Claim
138 words
In combination, a land vehicle having an earth-engaging tractive element, at least one synchronous electric motor on said vehicle having a stator winding and a rotor operatively connected to said tractive element, a prime mover on said vehicle, electric generator means including an alternator on said vehicle driven by said prime mover, means on said vehicle for selectively deriving a power signal which is a function of the desired tractive effort of said vehicle, manually controlled means for selectively deriving a brake signal, subtractive amplifier means for comparing said power and brake signals and for generating a difference signal which is a function of their difference, and control means between said electric generator means and said stator winding for regulating the voltage delivered by said generator means to said stator winding as a function of said difference signal.
Claim 30
Dependent Claim
102 words
In the combination of claim 27 wherein said subtractive amplifier means generates a difference signal of one polarity when said brake signal is greater than said power signal and of the opposite polarity when said power signal is greater than said brake signal, and wherein said control means includes absolute value amplifier means responsive to either polarity of said difference signal for providing an absolute value signal whose magnitude is a function of the magnitude of said difference signal, said control means regulating the voltage delivered by said generator means to said stator winding as a function of said absolute value signal.
Claim 31
Dependent Claim
56 words
In the combination of claim 27 wherein said means for deriving a brake signal is responsive to the magnitude of said power signal and, when it is at a predetermined partially operated position, derives a magnitude of brake signal greater than the magnitude of said power signal when said power signal deriving means is fully operated.
Claim 32
Dependent Claim
65 words
In the combination of claim 29 wherein said means for deriving a power signal includes a potentiometer, a direct current power source connected across the winding of said potentiometer, and a power signal amplifier coupled to the movable contact of said potentiometer and said means for deriving a brake signal includes a potentiometer having one end coupled to the output of said power signal amplifier.
Claim 33
Dependent Claim
29 words
In the combination of claim 28 wherein said control means includes brake sense means responsive to said one polarity of said difference signal for regeneratively braking said electric motor.
Claim 34
Dependent Claim
64 words
In the combination of claim 31 and including a cycloconverter between said generator means and said stator winding of said motor regulated by said control means and said brake sense means is responsive to said one polarity of said difference signal to shift the phase of the voltage supplied by said cycloconverter to said stator winding 180* to effect regenerative braking of said motor.
Claim 35
Dependent Claim
65 words
In the combination of claim 32 wherein said control means includes vector adder inductor means having a pair of energizing windings and a secondary winding inductively linked to said energizing windings for deriving a control signal for said cycloconverter and said brake sense means includes means for reversing both of said energizing windings to shift the phase of the voltage supplied by said cycloconverter 180*.
Claim 36
Dependent Claim
48 words
In the combination of claim 32 and including manually operable travel direction selector means for shifting the phase of the voltage supplied by said cycloconverter to said stator winding to reverse the direction of rotation of said Motor and thereby reverse the direction of travel of said vehicle.
Claim 37
Dependent Claim
69 words
In the combination of claim 34 wherein said control means includes vector adder inductor means having a pair of energizing windings and a secondary winding inductively linked to said energizing windings and in which said output signal is induced and said travel direction selector means includes means for reversing one of said energizing windings to shift the phase of said voltage supplied by said cycloconverter to said stator winding.
Claim 38
Dependent Claim
90 words
In the combination of claim 27 and including manually operable speed limit means for selectively deriving a speed limit signal, and wherein said control means includes tachometer means for deriving a speed signal which is a function of the speed of said motor and means for comparing said speed limit signal and said speed signal and for deriving a speed limit error signal when the latter exceeds the former, said speed limit error signal being an input to said subtractive amplifier means and being additive to said brake signal input.
Claim 39
Dependent Claim
115 words
In the combination of claim 36 and including a cycloconverter between said generator means and said stator winding of said motor regulated by said control means and travel direction selector means for shifting the phase of the voltage supplied by said cycloconverter to said stator winding to reverse the direction of rotation of said motor and thereby reverse the direction of travel of said vehicle and wherein said vehicle has a manually operable travel direction selector and speed limiting movable element, the direction of movement of said element controlling said travel direction selector means and the degree of movement thereof controlling said speed limit signal deriving means and the magnitude of said speed limit signal.
Claim 40
Dependent Claim
46 words
In the combination of claim 27 wherein said control means includes means responsive to an undesirable operating condition in said vehicle for reducing the voltage delivered by said generator means to said stator winding below that voltage level which is a function of said power signal.
Claim 41
Dependent Claim
92 words
In the combination of claim 28 wherein said control means includes a summing amplifier receiving said absolute value signal as an input and means responsive to an undesirable operating condition in said vehicle for deriving a fault signal which is an input to said summing amplifier, and wherein said summing amplifier provides a summing signal which is a function of the sum of said absolute value and fault signals and said control means regulates the power delivered by said generator means to said stator winding as a function of said summing signal.
Claim 42
Dependent Claim
33 words
In the combination of claim 39 wherein said means responsive to an undesirable operating condition comprises means for detecting a predetermined magnitude of overcurrent delivered by said generator means to said stator winding.
Claim 43
Dependent Claim
25 words
In the combination of claim 39 wherein said means responsive to an undesirable operating condition comprises means for detecting a predetermined overtemperature of said motor.
Claim 44
Dependent Claim
208 words
In combination, a land vehicle having a plurality of ground-engaging tractive elements, a plurality of inductor type synchronous motors on said vehicle each having a polyphase stator winding, a solid ferromagnetic rotor operatively connected to one of said tractive elements, and a field winding on said motor stator for generating magnetic poles in said rotor, a prime mover on said vehicle, polyphase electric generator means on said vehicle driven by said prime mover, a plurality of means each of which is associated with one of said motors operatively connected to said rotor for deriving an output signal having a frequency which is a function of the speed of said one motor, a plurality of polyphase frequency converters each of which is connected between said electric generator means and the stator winding of one of said motors controlled by said output signal which is a function of the speed of said one motor, a plurality of Control means each of which is associated with one of said motors for varying a condition of said output signal, and manually operated means for selectively deriving a power signal which is a function of the desired tractive effort of said vehicle, each of said control means being responsive to said power signal.
Claim 45
Dependent Claim
208 words
In combination, a land vehicle having a plurality of ground-engaging tractive elements, a plurality of inductor type synchronous motors on said vehicle each having a polyphase stator winding, a solid ferromagnetic rotor operatively connected to one of said tractive elements, and a field winding on said motor stator for generating magnetic poles in said rotor, a prime mover on said vehicle, polyphase electric generator means on said vehicle driven by said prime mover, a plurality of means each of which is associated with one of said motors operatively connected to said rotor for deriving an output signal having a frequency which is a function of the speed of said one motor, a plurality of polyphase frequency converters each of which is connected between said electric generator means and the stator winding of one of said motors controlled by said output signal which is a function of the speed of said one motor, a plurality of Control means each of which is associated with one of said motors for varying a condition of said output signal, and manually operated means for selectively deriving a power signal which is a function of the desired tractive effort of said vehicle, each of said control means being responsive to said power signal.
Claim 46
Dependent Claim
37 words
In the combination defined by claim 42 wherein said electric generator means includes a polyphase alternator on said vehicle connected to said motors for each pair of tractive elements, said alternator being driven by said prime mover.
Claim 47
Dependent Claim
59 words
In the combination of claim 42 including tachometer means associated with each of said motors for generating a speed signal which is a function of the speed of said motor, and wherein each of said control means regulates the voltage and shifts the phase of said output signal as a function of said speed signal and said power signal.
Claim 48
Dependent Claim
73 words
In the combination of claim 42 and including manually controlled means for selectively deriving a brake signal, and wherein each of said control means includes a subtractive amplifier for comparing said power and brake signals and generating a difference signal which is a function of their difference, each control means varying a condition of said polyphase output signal and controlling the energization of said field winding as a function of said difference signal.
Claim 49
Dependent Claim
106 words
In the combination of claim 45 wherein said subtractive amplifier provides a difference signal of one polarity when said brake signal is greater than said power signal and of the opposite polarity when said power signal is greater than said brake signal and each said control means also includes absolute value amplifier means responsive to either polarity of said difference signal for providing an absolute value signal whose magnitude is a function of the magnitude of said difference signal, each said control means regulating a condition of said output signal and controlling the energization of said field winding as a function of said absolute value signal.
Claim 50
Dependent Claim
65 words
In the combination of claim 46 and including a plurality of tachometer means each of which is associated with one of said motors for deriving a speed signal which is a function of the speed of said motor and wherein each said control means regulates the magnitude and phase of said polyphase output signal as functions of said absolute value signal and said speed signal.
Claim 51
Dependent Claim
71 words
In the combination of claim 46 and including a plurality of cycloconverters each of which is between said generator means and the stator winding of one of said motors and is controlled by said output signal and wherein each said control means includes brake sense means responsive to said one polarity of said difference signal for shifting the phase of said output signal 180* to effect regenerative braking of said motor.
Claim 52
Dependent Claim
54 words
In the combination of claim 48 wherein each of said control means includes vector adder inductor means having a pair of energizing windings and a secondary winding inductively linked to said energizing windings in which said output signal is induced and said brake sense means includes means for reversing both of said energizing windings.
Claim 53
Dependent Claim
49 words
In the combination of claim 45 wherein said vehicle has manually operated travel direction selector means for shifting the phase of all of said output signals to effect reversal of the direction of rotation of said plurality of motors and thus reverse the direction of travel of said vehicle.
Claim 54
Dependent Claim
69 words
In the combination of claim 50 wherein each of said control means includes vector adder inductor means having a pair of energizing windings and a secondary winding inductively linked to said energizing windings in which said output signal is induced and said travel direction selector means includes means in each of said control means for reversing one of said energizing windings to shift the phase of said output signal.
Claim 55
Dependent Claim
104 words
In the combination of claim 45 and including manually operable means for selectivelY deriving a speed limit signal which is a function of the desired maximum speed of said vehicle and wherein each of said control means includes means for deriving a speed signal which is a function of the speed of the associated motor and also includes speed limit means for comparing said speed signal and said speed limit signal and for deriving a speed limit error signal when the former exceeds the latter, said speed limit error signal being an input to said subtractive amplifier and being additive to said brake signal.
Claim 56
Dependent Claim
140 words
In the combination of claim 48 wherein said vehicle has a plurality of protective means each of which is associated with one of said motors and is responsive to an undesirable operating condition thereof for generating a fault signal, and each of said control means includes a summing amplifier receiving the corresponding fault signal and absolute value signal as inputs and providing a summing signal which is a function of their sum, and wherein each said control means also includes tachometer means for generating a speed signal which is a function of the speed of said motor and said control means regulates the phase and magnitude of said polyphase output signal as a function of said speed and summing signals and also includes means for applying a voltage to said field winding which is a function of said summing signal.
Claim 57
Dependent Claim
47 words
In the combination of claim 52 wherein said manually operable means for deriving a speed limit signal also actuates travel direction selector means for shifting the phase of all of said polyphase output signals to effect reversal of the direction of rotation of said plurality of motors.
Claim 58
Dependent Claim
59 words
In the combination of claim 54 wherein each said control means includes vector adder inductor means having a pair of energizing windings and a secondary winding inductively linked to said energizing windings in which said output signal is induced and said travel direction selector means includes means for reversing one of said energizing windings in each said control means.
Claim 59
Dependent Claim
82 words
In the combination of claim 53 wherein each frequency converter is a cycloconverter having controlled rectifiers between each phase of said generator means and said stator winding and each said control means includes means for deriving reference signals which are functions of the phase voltages produced by said generator means, means for combining said reference voltages and the associated phase output signals to derive composite sequence signals, and means controlled by said sequence signals for deriving gating signals for said controlled rectifiers.
Claim 60
Dependent Claim
76 words
In the combination of claim 56 wherein said gating signal deriving means includes means for detecting when said gating signals cross the zero axis, and wherein the maximum frequency of said output signals over the speed range of said motors is f cycles per second, and including governor means for controlling the speed of said prime mover so that said generator means produces a polyphase voltage having a frequency of at least 2f cycles per second.
Claim 61
Dependent Claim
68 words
In the combination of claim 37 wherein said subtractive amplifier means generates a difference signal of one polarity when said brake signal is greater than said power signal and of the opposite polarity when said power signal is greater than said brake signal and wherein said control means includes brake sense means responsive to said one polarity of said difference signal for regeneratively braking said synchronous electric motor.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-03 | 1974-11-02 | 1975-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-03 | 1978-11-02 | 1979-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-03 | 1982-11-02 | 1983-05-04 | $7700.00 | Window Closed / Lapsed |