Patent US3875955A successfully refreshed from Google Patents.
US3875955A
Expired / Lapsed
US
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Digital fluid flow rate measurement or control system
Assignee: Process Systems Inc
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Filing: 1974-01-10
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Granted: 1975-04-08
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Expires: 1994-01-10
Abstract
Abstract A plurality of individually actuatable, value weighted digital bistable valve elements in parallel interconnect a fluid source to a fluid receiver. A linear relationship is preferably maintained between the resultant fluid flow rate from the source to the receiver and the product of a flow rate determinative fluid parameter times the sum of the weighted values of the digital valve elements in the open state. The fluid parameter is sensed, the states of the digital valve elements are controlled, and a flow rate representative signal is derived from the states of the valve elements and the fluid parameter. If the fluid is liquid, the parameter is the square root of the pressure difference across the valve elements, in the absence of cavitating venturis, and is the square root of the difference between the upstream pressure and the vapor pressure of the liquid in the presence of cavitating venturis. If the fluid is gas, the parameter is the source pressure divided by the square root of the source temperature. For measurement, the states of the digital valve elements are controlled to maintain the value of the fluid parameter constant. For control the states of the digital valve elements are controlled to establish a set point flow rate.
Inventors
- 👤 Robert A Gallatin
- 👤 Jr Addison W Langill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 10:16
CPC Classifications
G; G05; G05D; G05D7/00; G05D7/06; G05D7/0617; G05D7/0629; G05D7/0635; G01; G01F; G01F1/00; G01F1/05; G01F1/34; G01F1/36; G01F1/363; G01F1/76; G01F1/86; G01F1/88; G01F15/00; G01F15/07; G01F15/075; G01F15/0755; Y; Y10; Y10T; Y10T137/00; Y10T137/0318; Y10T137/0396; Y10T137/7722; Y10T137/7758; Y10T137/7759; Y10T137/776; Y10T137/7761
Claims Analysis
Total Claims: 55
Claim 1
Independent Claim
211 words
A digital fluid flow rate measurement or control system comprising: a source of fluid at a first pressure; a fluid receiver at a second pressure lower than the first pressure; a plurality of individually actuatable, value weighted digital bistable valve elements interconnecting the source to the receiver, each valve element assuming exclusively either an open state in which fluid flows from the source through the valve element to the receiver or a closed state in which no fluid flows from the source through the valve element to the receiver such that the resultant fluid flow rate from the source to the receiver is a function of the product of a flow rate determinative fluid parameter times the sum of the weighted values of the digital valve elements in the open state; means for sensing the fluid parameter and generating a first signal representaitve of the value of the fluid parameter; means responsive to the value of the fluid parameter and the states of the digital valve elements for generating a second signal representative of the value of the resultant fluid flow rate; and means responsive to one of the signals for controlling the states of the digital valve elements so as to maintain constant the value represented by the one signal.
Claim 2
Dependent Claim
211 words
A digital fluid flow rate measurement or control system comprising: a source of fluid at a first pressure; a fluid receiver at a second pressure lower than the first pressure; a plurality of individually actuatable, value weighted digital bistable valve elements interconnecting the source to the receiver, each valve element assuming exclusively either an open state in which fluid flows from the source through the valve element to the receiver or a closed state in which no fluid flows from the source through the valve element to the receiver such that the resultant fluid flow rate from the source to the receiver is a function of the product of a flow rate determinative fluid parameter times the sum of the weighted values of the digital valve elements in the open state; means for sensing the fluid parameter and generating a first signal representaitve of the value of the fluid parameter; means responsive to the value of the fluid parameter and the states of the digital valve elements for generating a second signal representative of the value of the resultant fluid flow rate; and means responsive to one of the signals for controlling the states of the digital valve elements so as to maintain constant the value represented by the one signal.
Claim 3
Dependent Claim
44 words
The system of claim 1, in which the fluid is incompressible, the fluid parameter is the square root of the difference between the first and second pressures, and the sensing means senses the square root of the difference between the first and second pressures.
Claim 4
Dependent Claim
70 words
The system of claim 1, in which the fluid is incompressible, each digital valve element has a passage from the source to the receiver which includes a converging-diverging nozzle designed to maintain the vapor phase of the fluid at its throat, the fluid parameter is the square root of the difference between the first pressure and the vapor pressure of the fluid, and the sensing means senses the first pressure.
Claim 5
Dependent Claim
100 words
The system of claim 1, in which the fluid is compressible, the fluid parameter is the absolute stagnation pressure divided by the square root of the absolute stagnation temperature, the sensing means senses the first pressure and the temperature of the fluid at the source, each digital valve element has a flow passage from the source to the receiver, a flow determining orifice formed in the flow passage, and a region in the flow passage through which the fluid flows at sonic velocity thereby isolating the flow passage upstream of the flow determining orifice from variations in the second pressure.
Claim 6
Dependent Claim
50 words
The system of claim 1, in which the fluid is compressible, the fluid parameter is the first pressure divided by the square root of the absolute stagnation temperature, and the sensing means senses the first pressure, the second pressure, and the temperature of the fluid at the source or receiver.
Claim 7
Dependent Claim
29 words
The system of claim 1, in which the controlling means comprises means for controlling the states of the valve elements to maintain the value of the fluid parameter constant.
Claim 8
Dependent Claim
56 words
The system of claim 6, in which the controlling means additionally comprises: a source of a third signal proportional to a desired fluid flow rate from the source to the receiver, and means responsive to the difference between the third and second signals for changing the states of the digital valve elements to reduce such difference.
Claim 9
Dependent Claim
30 words
The system of claim 6, additionally comprising an indicator responsive to the controlling means for displaying the states of the valve elements as a measurement of the fluid flow rate.
Claim 10
Dependent Claim
55 words
The system of claim 1, in which the controlling means comprises: a source of a third signal proportional to a desired fluid flow rate from the source to the receiver, and means responsive to the difference between the third and second signals for changing the states of the digital valve elements to reduce such difference.
Claim 11
Dependent Claim
71 words
The system of claim 9, in which the values of the respective digital valve elements are weighted according to a binary code, the third signal comprises a plurality of binary signals equal in number to the digital valve elements and weighted according to the binary code, and the second signal comprises a plurality of binary signals equal in number to the digital valve elements and weighted according to the binary code.
Claim 12
Dependent Claim
34 words
The system of claim 1, in which the fluid flow rate through at least some of the respective digital valve elements in the open state are weighted according to a geometric progression of two.
Claim 13
Dependent Claim
23 words
The system of claim 1, additionally comprising means for maintaining a linear function relationship between the resultant fluid flow rate and the product.
Claim 14
Dependent Claim
24 words
The system of claim 12, in which the valve elements are arranged so the fluid streams flowing through them are directed at each other.
Claim 15
Dependent Claim
28 words
The system of claim 1, in which the one signal is the first signal and the value of the fluid parameter is maintained constant by the controlling means.
Claim 16
Dependent Claim
30 words
The system of claim 1, in which the one signal is the second signal and the value of the resultant fluid flow rate is maintained constant by the controlling means.
Claim 17
Dependent Claim
31 words
The system of claim 1, additionally comprising switching means for alternatively applying to the controlling means the first signal to measure flow rate or the second signal to control flow rate.
Claim 18
Dependent Claim
29 words
The system of claim 1, in which the second signal generating means comprises a signal multiplier responsive to the first signal and the states of the digital valve elements.
Claim 19
Dependent Claim
39 words
The system of claim 17, in which the sensing and first signal generating means comprises transducer means for generating a signal proportional to the fluid parameter and a function generator for modifying the signal generated by the transducer means.
Claim 20
Dependent Claim
158 words
A digital liquid flow rate measurement or control device comprising: an upstream liquid manifold; a downstream liquid manifold; a plurality of at least three individually actuatable, digital valve elements, each valve element having a liquid flow passage leading from the upstream manifold to the downstream manifold, a sealable orifice in the passage, and a bistable plug positionable exclusively in a first state in which the plug seals the orifice to prevent liquid flow through the passage or a second state in which the plug unseals the orifice to permit liquid flow through the passage; first liquid pressure sensing means located in the upstream manifold; second liquid pressure sensing means located in the downstream manifold; and means responsive to the liquid pressure difference sensed by the first and second pressure sensing means and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate from the upstream manifold to the downstream manifold.
Claim 21
Dependent Claim
158 words
A digital liquid flow rate measurement or control device comprising: an upstream liquid manifold; a downstream liquid manifold; a plurality of at least three individually actuatable, digital valve elements, each valve element having a liquid flow passage leading from the upstream manifold to the downstream manifold, a sealable orifice in the passage, and a bistable plug positionable exclusively in a first state in which the plug seals the orifice to prevent liquid flow through the passage or a second state in which the plug unseals the orifice to permit liquid flow through the passage; first liquid pressure sensing means located in the upstream manifold; second liquid pressure sensing means located in the downstream manifold; and means responsive to the liquid pressure difference sensed by the first and second pressure sensing means and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate from the upstream manifold to the downstream manifold.
Claim 22
Dependent Claim
36 words
The device of claim 19, additionally comprising means for controlling the states of the respective plugs to maintain the liquid pressure difference sensed by the first and second pressure sensing means at a substantially constant value.
Claim 23
Dependent Claim
32 words
The device of claim 20, additionally comprising an indicator responsive to the resultant fluid flow rate representative signal for displaying the liquid flow rate from the upstream manifold to the downstream manifold.
Claim 24
Dependent Claim
67 words
The device of claim 19, additionally comprising: a source of a set point signal proportional to a desired liquid flow rate from the upstream manifold to the downstream manifold, and means responsive to the difference between the resultant flow rate representative and set point signals for changing the plug states of the respective digital valve elements to equalize the desired flow rate and the actual flow rate.
Claim 25
Dependent Claim
50 words
The device of claim 19, additionally comprising means for maintaining a linear relationship between the resultant flow rate through the valve elements in the second position and the product of the sensed pressure difference times the sum of the effective cross-sectional areas of the valve elements in the second state.
Claim 26
Dependent Claim
165 words
A digital liquid flow measurement or control device comprising: an upstream liquid manifold; a downstream liquid manifold; a plurality of at least three individually actuatable, digital valve elements, each valve element having a liquid flow passage leading from the upstream manifold to the downstream manifold, a sealable orifice in the passage, a bistable plug positioned exclusively in a first state in which the plug seals the orifice to prevent liquid flow through the passage or a second state in which the plug unseals the orifice to permit liquid flow through the passage, and a cavitating venturi in the passage at which the liquid remains in its vapor phase when the plug is in the second state; liquid pressure sensing means located in the upstream manifold; and means responsive to the liquid pressure sensed by the pressure sensing means and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate from the upstream manifold to the downstream manifold.
Claim 27
Dependent Claim
165 words
A digital liquid flow measurement or control device comprising: an upstream liquid manifold; a downstream liquid manifold; a plurality of at least three individually actuatable, digital valve elements, each valve element having a liquid flow passage leading from the upstream manifold to the downstream manifold, a sealable orifice in the passage, a bistable plug positioned exclusively in a first state in which the plug seals the orifice to prevent liquid flow through the passage or a second state in which the plug unseals the orifice to permit liquid flow through the passage, and a cavitating venturi in the passage at which the liquid remains in its vapor phase when the plug is in the second state; liquid pressure sensing means located in the upstream manifold; and means responsive to the liquid pressure sensed by the pressure sensing means and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate from the upstream manifold to the downstream manifold.
Claim 28
Dependent Claim
32 words
The device of claim 24, additionally comprising means for controlling the states of the respective plugs to maintain the liquid pressure sensed by the pressure sensing means at a substantially constant value.
Claim 29
Dependent Claim
31 words
The device of claim 25, additionally comprising an indicator responsive to the resultant flow rate representative signal for displaying the liquid flow rate from the upstream manifold to the downstream manifold.
Claim 30
Dependent Claim
67 words
The device of claim 24, additionally comprising: a source of a set point signal proportional to a desired liquid flow rate from the upstream manifold to the downstream manifold, and means responsive to the difference between the resultant flow rate representative and set point signals for changing the plug states of the respective digital valve elements to equalize the desired flow rate and the actual flow rate.
Claim 31
Dependent Claim
188 words
A digital gas flow measurement or control device comprising: an upstream gas manifold; a downstream gas manifold; a plurality of at least three individually actuatable, digital valve elements, each valve element having a gas flow passage leading from the upstream manifold to the downstream manifold, a sealable orifice in the passage, a bistable plug positionable exclusively in a first state in which the plug seals the orifice to prevent gas flow through the passage or a second state in which the plug unseals the orifice to permit gas flow through the passage, and a critical flow orifice through which gas flow at sonic velocity is maintained when the plug is in the second state; absolute gas pressure sensing means located in the upstream manifold, absolute temperature sensing means located in the upstream manifold; and means responsive to the absolute pressure sensed by the pressure sensing means divided by the square root of the absolute temperature sensed by the temperature sensing means and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate from the upstream manifold to the downstream manifold.
Claim 32
Dependent Claim
188 words
A digital gas flow measurement or control device comprising: an upstream gas manifold; a downstream gas manifold; a plurality of at least three individually actuatable, digital valve elements, each valve element having a gas flow passage leading from the upstream manifold to the downstream manifold, a sealable orifice in the passage, a bistable plug positionable exclusively in a first state in which the plug seals the orifice to prevent gas flow through the passage or a second state in which the plug unseals the orifice to permit gas flow through the passage, and a critical flow orifice through which gas flow at sonic velocity is maintained when the plug is in the second state; absolute gas pressure sensing means located in the upstream manifold, absolute temperature sensing means located in the upstream manifold; and means responsive to the absolute pressure sensed by the pressure sensing means divided by the square root of the absolute temperature sensed by the temperature sensing means and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate from the upstream manifold to the downstream manifold.
Claim 33
Dependent Claim
47 words
The device of claim 28, additionally comprising means for controlling the states of the respective plugs to maintain the absolute pressure sensed by the pressure sensing means divided by the square root of the absolute temperature sensed by the temperature sensing means at a substantially constant value.
Claim 34
Dependent Claim
31 words
The device of claim 29, additionally comprising an indicator responsive to the resultant flow rate representative signal for displaying the gas flow rate from the upstream manifold to the downstream manifold.
Claim 35
Dependent Claim
67 words
The device of claim 28, additionally comprising: a source of a set point signal proportional to a desired gas flow rate from the upstream manifold to the downstream manifold, and means responsive to the difference between the resultant flow rate representative and set point signals for changing the plug states of the respective digital valve elements to equalize the desired flow rate and the actual flow rate.
Claim 36
Dependent Claim
18 words
The device of claim 28, in which the critical flow orifice comprises the throat of a converging-diverging nozzle.
Claim 37
Dependent Claim
173 words
A digital gas flow measurement or control device comprising: an upstream gas manifold; a downstream gas manifold; a plurality of at least three individually actuatable, digital valve elements, each valve element having a gas flow passage leading from the upstream manifold to the downstream manifold, a sealable orifice in the passage, and a bistable plug positionable exclusively in a first state in which the plug seals the orifice to prevent gas flow through the passage or a second state in which the plug unseals the orifice to permit gas flow through the passage; first gas pressure sensing means located in the upstream manifold; second gas pressure sensing means located in the downstream manifold; temperature sensing means located in one of the manifolds; and means responsive to the pressures sensed by the first and second pressure sensing means and the temperature sensed by the temperature sensing means and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate from the upstream manifold to the downstream manifold.
Claim 38
Dependent Claim
173 words
A digital gas flow measurement or control device comprising: an upstream gas manifold; a downstream gas manifold; a plurality of at least three individually actuatable, digital valve elements, each valve element having a gas flow passage leading from the upstream manifold to the downstream manifold, a sealable orifice in the passage, and a bistable plug positionable exclusively in a first state in which the plug seals the orifice to prevent gas flow through the passage or a second state in which the plug unseals the orifice to permit gas flow through the passage; first gas pressure sensing means located in the upstream manifold; second gas pressure sensing means located in the downstream manifold; temperature sensing means located in one of the manifolds; and means responsive to the pressures sensed by the first and second pressure sensing means and the temperature sensed by the temperature sensing means and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate from the upstream manifold to the downstream manifold.
Claim 39
Dependent Claim
47 words
The device of claim 33, additionally comprising means for controlling the states of the respective plugs to maintain the pressure sensed by the first pressure sensing means divided by the square root of the absolute temperature sensed by the temperature sensing means at a substantially constant value.
Claim 40
Dependent Claim
31 words
The device of claim 34, additionally comprising an indicator responsive to the resultant flow rate representative signal for displaying the gas flow rate from the upstream manifold to the downstream manifold.
Claim 41
Dependent Claim
67 words
The device of claim 33, additionally comprising: a source of a set point signal proportional to a desired gas flow rate from the upstream manifold to the downstream manifold, and means responsive to the difference between the resultant flow rate representative and set point signals for changing the plug states of the respective digital valve elements to equalize the desired flow rate and the actual flow rate.
Claim 42
Independent Claim
172 words
A method of measuring the flow rate in a fluid line between a source of fluid at a first pressure and a fluid receiver at a second pressure lower than the first pressure, the method comprising the steps of: interconnecting a plurality of individually actuatable, value weighted digital bistable valve elements in parallel in the fluid line between the source and the receiver, each valve element assuming exclusively either an open state in which fluid flows from the source through the valve element to the receiver or a closed state in which no fluid flows from the source through the valve element to the receiver such that the resultant flow rate through the fluid line is a function of the product of a flow rate determinative fluid parameter times the sum of the weighted values of the digital valve elements in the open state; sensing the fluid parameter; and controlling the states of the digital valve elements to maintain the fluid parameter constant as the flow rate through the fluid line varies.
Claim 43
Independent Claim
172 words
A method of measuring the flow rate in a fluid line between a source of fluid at a first pressure and a fluid receiver at a second pressure lower than the first pressure, the method comprising the steps of: interconnecting a plurality of individually actuatable, value weighted digital bistable valve elements in parallel in the fluid line between the source and the receiver, each valve element assuming exclusively either an open state in which fluid flows from the source through the valve element to the receiver or a closed state in which no fluid flows from the source through the valve element to the receiver such that the resultant flow rate through the fluid line is a function of the product of a flow rate determinative fluid parameter times the sum of the weighted values of the digital valve elements in the open state; sensing the fluid parameter; and controlling the states of the digital valve elements to maintain the fluid parameter constant as the flow rate through the fluid line varies.
Claim 44
Dependent Claim
31 words
The method of claim 37, additionally comprising the step of maintaining a linear function relationship between the resultant flow rate through the valve elements in the open state and the product.
Claim 45
Dependent Claim
168 words
A digital fluid flow rate measurement or control system comprising: a source of fluid at a first pressure; a fluid receiver at a second pressure lower than the first pressure; a plurality of individually actuatable, value weighted digital bistable valve elements interconnecting the source to the receiver, each valve element assuming exclusively either an open state in which fluid flows from the source through the valve element to the receiver or a closed state in which no fluid flows from the source through the valve element to the receiver; means for maintaining a linear relationship between the resultant fluid flow rate from the source to the receiver and the product of a flow rate determinative fluid parameter times the sum of the weighted values of the digital valve elements in the open state; means for sensing the fluid parameter; and means responsive to the value of the fluid parameter and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate.
Claim 46
Dependent Claim
168 words
A digital fluid flow rate measurement or control system comprising: a source of fluid at a first pressure; a fluid receiver at a second pressure lower than the first pressure; a plurality of individually actuatable, value weighted digital bistable valve elements interconnecting the source to the receiver, each valve element assuming exclusively either an open state in which fluid flows from the source through the valve element to the receiver or a closed state in which no fluid flows from the source through the valve element to the receiver; means for maintaining a linear relationship between the resultant fluid flow rate from the source to the receiver and the product of a flow rate determinative fluid parameter times the sum of the weighted values of the digital valve elements in the open state; means for sensing the fluid parameter; and means responsive to the value of the fluid parameter and the states of the digital valve elements for generating a signal representative of the resultant fluid flow rate.
Claim 47
Dependent Claim
25 words
The system of claim 39, additionally comprising means for controlling the states of the valve elements to maintain the value of the fluid parameter constant.
Claim 48
Dependent Claim
53 words
The system of claim 39, in which the generating means is responsive to the sensed value of the fluid parameter and the states of the digital valve elements, the system additionally comprising means for controlling the states of the digital valve elements responsive to the signal representative of the resultant fluid flow rate.
Claim 49
Dependent Claim
86 words
The system of claim 39, in which the fluid is incompressible, the fluid parameter is the square root of the difference between the first and second pressures, the sensing means senses the square root of the difference between the first and second pressures, and the means for maintaining a linear relationship comprises means for establishing a sufficiently low maximum difference between the first and second pressures to prevent formation of vena contractas having pressure dependent cross-sectional areas downstream of the valve elements in the open state.
Claim 50
Dependent Claim
73 words
The system of claim 39, in which the fluid is incompressible, the fluid parameter is the square root of the difference between the first and second pressures, the sensing means senses the square root of the difference between the first and second pressures, and the means for maintaining a linear relationship comprises means for directing the streams from the valve elements in the open state at each other to dissipate the vena contractas.
Claim 51
Dependent Claim
54 words
The system of claim 39, in which the fluid is incompressible, the fluid parameter is the square root of difference between the first pressure and the vapor pressure of the fluid, the sensing means senses the first pressure, and the means for maintaining a linear relationship comprises a cavitating venturi in each valve element.
Claim 52
Dependent Claim
69 words
The system of claim 39, in which the fluid is compressible, the fluid parameter is the absolute stagnation pressure divided by the square root of the absolute stagnation temperature, the sensing means senses the first pressure and the temperature of the fluid at the source, and the means for maintaining a linear relationship comprises a critical flow orifice in each valve element through which fluid flows at sonic velocity.
Claim 53
Dependent Claim
16 words
The system of claim 45, in which the orifice is the throate of a converging-diverging nozzle.
Claim 54
Independent Claim
200 words
A method for operating a digital fluid flow control system having a plurality of individually actuatable, value weighted digital bistable valve elements interconnecting a source of fluid at a first pressure to a receiver at a second pressure lower than the first pressure, each valve element assuming exclusively either an open state in which fluid flows from the source through the valve element to the receiver or a closed state in which no fluid flows from the source through the valve element to the receiver such that the resultant fluid flow rate from the source to the receiver is a function of the product of a flow rate determinative fluid parameter times the sum of weighted weighthed values of the digital valve elements in the open state, the method comprising the steps of: sensing the fluid parameter and generating a first signal representative of the value of the fluid parameter; generating a second signal representative of the product of the value of the fluid parameter and the states of the digital valve elements; and controlling the states of the digital valve elements responsive to one of the signals so as to maintain constant the value representated by the one signal.
Claim 55
Independent Claim
200 words
A method for operating a digital fluid flow control system having a plurality of individually actuatable, value weighted digital bistable valve elements interconnecting a source of fluid at a first pressure to a receiver at a second pressure lower than the first pressure, each valve element assuming exclusively either an open state in which fluid flows from the source through the valve element to the receiver or a closed state in which no fluid flows from the source through the valve element to the receiver such that the resultant fluid flow rate from the source to the receiver is a function of the product of a flow rate determinative fluid parameter times the sum of weighted weighthed values of the digital valve elements in the open state, the method comprising the steps of: sensing the fluid parameter and generating a first signal representative of the value of the fluid parameter; generating a second signal representative of the product of the value of the fluid parameter and the states of the digital valve elements; and controlling the states of the digital valve elements responsive to one of the signals so as to maintain constant the value representated by the one signal.
References Cited (Backward Citations)
US2627280A
Cited
US3776249A
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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) | 1978-04-07 | 1978-10-07 | 1979-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-07 | 1982-10-07 | 1983-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-07 | 1986-10-07 | 1987-04-08 | $7700.00 | Window Closed / Lapsed |