US4991655A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Combined alarm and back-flow prevention arrangement for fire suppression sprinkler system
Assignee: BACK-FLO ALARM VALVE Co Inc
•
Filing: 1989-04-10
•
Granted: 1991-02-12
•
Expires: 2009-04-10
Abstract
Abstract An alarm valve and a backflow preventer are provided by a check valve and an alarm valve with a passageway provided between the check valve and the alarm valve preferably having a relief valve which selectively drains the passageway in response to the pressure in the main conduit upstream of the check valve. An alarm is sounded when the alarm valve is open. An impeller flow sensor may be provided in the backflow prevention device.
Inventors
- 👤 George J. McHugh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:04
CPC Classifications
E; E03; E03B; E03B7/00; E03B7/07; E03B7/072; A; A62; A62C; A62C35/00; A62C35/58; A62C35/68; F; F16; F16K; F16K15/00; Y; Y10; Y10T; Y10T137/00; Y10T137/3149; Y10T137/3185; Y10T137/3294; Y10T137/3331; Y10T137/8158; Y10T137/8326
Claims Analysis
Total Claims: 78
Claim 1
Independent Claim
172 words
A combined alarm valve and backflow prevention arrangement for a fire suppression sprinkler system, having a main conduit and an arrangement of individual sprinklers downstream of the main conduit, said combined alarm valve and backflow prevention arrangement comprising: a first check valve provided in said main conduit upstream of said arrangement of individual sprinklers; an alarm valve formed by a second check valve provided in said main conduit downstream of said first check valve and upstream of said arrangement of individual sprinklers; alarm means for indicating when the second check valve is open; and means for providing fluid communication between said first check valve and said alarm valve through a passageway, said means for providing fluid communication including relief valve means for selectively draining said passageway in response to the hydraulic pressure in said main conduit of the fire suppression system upstream of the first check valve, whereby said first check valve and said second check valve together provide a reduced pressure zone, double check valve backflow prevention and alarm valve arrangement.
Claim 2
Dependent Claim
172 words
A combined alarm valve and backflow prevention arrangement for a fire suppression sprinkler system, having a main conduit and an arrangement of individual sprinklers downstream of the main conduit, said combined alarm valve and backflow prevention arrangement comprising: a first check valve provided in said main conduit upstream of said arrangement of individual sprinklers; an alarm valve formed by a second check valve provided in said main conduit downstream of said first check valve and upstream of said arrangement of individual sprinklers; alarm means for indicating when the second check valve is open; and means for providing fluid communication between said first check valve and said alarm valve through a passageway, said means for providing fluid communication including relief valve means for selectively draining said passageway in response to the hydraulic pressure in said main conduit of the fire suppression system upstream of the first check valve, whereby said first check valve and said second check valve together provide a reduced pressure zone, double check valve backflow prevention and alarm valve arrangement.
Claim 3
Dependent Claim
63 words
The arrangement of claim 1 wherein the means for providing communication between said first check valve and said alarm valve comprises a plumbing fitting, said plumbing fitting comprising: a conduit having means for coupling said plumbing fitting to the first check valve upstream of the plumbing fitting and means for coupling said plumbing fitting to the alarm valve downstream of the plumbing fitting.
Claim 4
Dependent Claim
26 words
The arrangement of claim 1 wherein said relief valve means comprises a hydraulically operated relief valve which discharges to a drain which is vented to atmosphere.
Claim 5
Dependent Claim
43 words
The arrangement of claim 3 wherein said first check valve has a valve member and a valve seat, the inlet of the hydraulically operated relief valve being arranged vertically lower than the lowermost portion of the valve seat of the first check valve.
Claim 6
Dependent Claim
13 words
The arrangement of claim 4 wherein the first check valve is spring loaded.
Claim 7
Dependent Claim
32 words
The arrangement of claim 4 wherein said means for providing fluid communication includes means for admitting air into the passageway when the pressure in the passageway falls below a first predetermined amount.
Claim 8
Dependent Claim
37 words
The arrangement of claim 1 further comprising means for admitting air into said main conduit upstream of said alarm valve when the pressure in said main conduit upstream of the alarm valve falls below a predetermined amount.
Claim 9
Dependent Claim
57 words
The arrangement of claim 2 wherein said conduit has an inlet and an outlet, said inlet including said means for coupling said fitting to said first check valve and said outlet including said means for coupling said fitting to said alarm valve, said inlet and said outlet being oriented at 90 degrees with respect to one another.
Claim 10
Dependent Claim
34 words
The arrangement of claim 1 wherein said alarm means includes a fluid driven motor alarm which is actuated by fluid supplied downstream of said second check valve, when said second check valve is open.
Claim 11
Dependent Claim
36 words
The arrangement of claim 1 wherein said first check valve, said alarm valve and said means for providing fluid communication between said first check valve and said alarm valve are all provided within a common housing.
Claim 12
Dependent Claim
84 words
The arrangement of claim 1 wherein said first check valve and said means for providing fluid communication between said first check valve and said alarm valve through a passageway are provided within a common housing, said common housing having an inlet and an outlet, said inlet including means for coupling said housing to said main conduit and said outlet including means for coupling said common housing to said alarm valve, said inlet and said outlet being oriented substantially linearly with respect to one another.
Claim 13
Dependent Claim
56 words
The arrangement of claim 11 wherein said common housing is oriented vertically with said passageway within said common housing providing a first portion which is oriented generally upwardly from said inlet to said first check valve and a second portion which is oriented generally downwardly and then upwardly from said first check valve to said outlet.
Claim 14
Dependent Claim
78 words
The arrangement of claim 2 wherein said conduit has an inlet and an outlet, said inlet including said means for coupling said fitting to said first check valve and said outlet including said means for coupling said fitting to said alarm valve, said inlet and said outlet being oriented generally linearly with respect to one another with said conduit being oriented generally horizontally, said conduit including a mid-portion which is vertically lower than said inlet and said outlet.
Claim 15
Dependent Claim
69 words
The arrangement of claim 2 wherein said conduit has an inlet and an outlet, said inlet including said means for coupling said fitting to said first check valve and said outlet including said means for coupling said fitting to said alarm valve, said inlet and said outlet being oriented at 90 degrees with respect to one another, said conduit including a mid-portion which is vertically lower than said inlet.
Claim 16
Dependent Claim
39 words
The arrangement of claim 14 wherein said outlet is vertically lower than said inlet, with a lowermost portion of a seat of said alarm valve being lower than a lowermost portion of a seat of said first check valve.
Claim 17
Dependent Claim
15 words
The arrangement of claim 12 wherein said first check valve is a stop check valve.
Claim 18
Dependent Claim
104 words
A plumbing fitting for use in a fire suppression system whereby a check valve and an alarm valve may be connected to one another to provide a double check valve, reduced pressure zone, backflow preventer and an alarm valve arrangement, said plumbing fitting comprising: a conduit having means for coupling said plumbing fitting to the check valve upstream of the plumbing fitting and means for coupling said plumbing fitting to the alarm valve downstream of the plumbing fitting; and means for draining the plumbing fitting in response to the pressure in a main conduit of the fire suppression system upstream of the alarm valve.
Claim 19
Dependent Claim
104 words
A plumbing fitting for use in a fire suppression system whereby a check valve and an alarm valve may be connected to one another to provide a double check valve, reduced pressure zone, backflow preventer and an alarm valve arrangement, said plumbing fitting comprising: a conduit having means for coupling said plumbing fitting to the check valve upstream of the plumbing fitting and means for coupling said plumbing fitting to the alarm valve downstream of the plumbing fitting; and means for draining the plumbing fitting in response to the pressure in a main conduit of the fire suppression system upstream of the alarm valve.
Claim 20
Dependent Claim
24 words
The plumbing fitting of claim 17 wherein the means for draining the plumbing fitting comprises a hydraulically operated relief valve which discharges to atmosphere.
Claim 21
Dependent Claim
28 words
The plumbing fitting of claim 18 wherein said hydraulically operated relief valve is adapted to be in fluid communication with the main conduit upstream of the check valve.
Claim 22
Dependent Claim
25 words
The plumbing fitting of claim 17 further comprising means for selectively venting said conduit when the pressure in the conduit is below a predetermined amount.
Claim 23
Dependent Claim
26 words
The plumbing fitting of claim 17 further comprising means for selectively venting said conduit when the pressure in the conduit is generally less than atmospheric pressure.
Claim 24
Dependent Claim
59 words
The plumbing fitting of claim 17 wherein said conduit has an inlet and an outlet, said inlet including said means for coupling said plumbing fitting to said check valve and said outlet including said means for coupling said plumbing fitting to said alarm valve, said inlet and said outlet being oriented at 90 degrees with respect to one another.
Claim 25
Dependent Claim
99 words
The plumbing fitting of claim 17 wherein said conduit has an inlet and an outlet, said inlet including said means for coupling said plumbing fitting to said check valve and said outlet including said means for coupling said plumbing fitting to said alarm valve, said inlet and said outlet being oriented at 90 degrees with respect to one another, said plumbing fitting further comprising means for selectively venting said conduit when the pressure in the conduit is generally less than atmospheric pressure, the check valve upstream of the plumbing fitting being a stop-check valve that is spring-loaded to close.
Claim 26
Dependent Claim
228 words
A combined alarm valve and backflow prevention arrangement for a fire suppression, water sprinkler system, having a main conduit and an arrangement of individual water sprinklers downstream of the main conduit, said combined alarm valve and backflow prevention arrangement comprising: a first check valve provided in said main conduit upstream of said arrangement of individual sprinklers; an alarm valve including a second check valve provided in said main conduit downstream of said first check valve and upstream of said arrangement of individual sprinklers; alarm means for indicating when the alarm valve is open; and means for providing fluid communication between said first check valve and said alarm valve in a passageway, said means for providing fluid communication including means for draining the passageway in response to the pressure in said main conduit of the fire suppression system and means for venting said passageway when the pressure in the passageway is below a predetermined amount, said means for providing communication between said first check valve and said alarm valve comprising a plumbing fitting, said plumbing fitting having means for coupling said plumbing fitting to the first check valve upstream of the plumbing fitting and means for coupling said plumbing fitting to the alarm valve downstream of the plumbing fitting, said first check valve and said second check valve together providing a double check valve, reduced pressure zone, backflow preventer.
Claim 27
Dependent Claim
228 words
A combined alarm valve and backflow prevention arrangement for a fire suppression, water sprinkler system, having a main conduit and an arrangement of individual water sprinklers downstream of the main conduit, said combined alarm valve and backflow prevention arrangement comprising: a first check valve provided in said main conduit upstream of said arrangement of individual sprinklers; an alarm valve including a second check valve provided in said main conduit downstream of said first check valve and upstream of said arrangement of individual sprinklers; alarm means for indicating when the alarm valve is open; and means for providing fluid communication between said first check valve and said alarm valve in a passageway, said means for providing fluid communication including means for draining the passageway in response to the pressure in said main conduit of the fire suppression system and means for venting said passageway when the pressure in the passageway is below a predetermined amount, said means for providing communication between said first check valve and said alarm valve comprising a plumbing fitting, said plumbing fitting having means for coupling said plumbing fitting to the first check valve upstream of the plumbing fitting and means for coupling said plumbing fitting to the alarm valve downstream of the plumbing fitting, said first check valve and said second check valve together providing a double check valve, reduced pressure zone, backflow preventer.
Claim 28
Dependent Claim
69 words
The arrangement of claim 24 wherein the means for draining comprises a hydraulically operated relief valve which discharges to atmosphere and wherein said first check valve means includes a first check valve which is spring loaded having a valve member and a valve seat, an inlet of the hydraulically operated relief valve being arranged vertically lower than the lowermost portion of the valve seat of the first check valve.
Claim 29
Dependent Claim
68 words
The arrangement of claim 25 wherein said hydraulically operated relief valve is adapted to be in fluid communication with the main conduit upstream of the first check valve and wherein said means for venting is adapted to provide communication between the first check valve and atmosphere to admit air into the main conduit in the event that the pressure in the passageway is generally less than atmospheric pressure.
Claim 30
Dependent Claim
60 words
The arrangement of claim 26 wherein said plumbing fitting has an inlet and an outlet, said inlet including said means for coupling said plumbing fitting to said first check valve and said outlet including said means for coupling said plumbing fitting to said alarm valve, said inlet and said outlet being oriented at 90 degrees with respect to one another.
Claim 31
Dependent Claim
32 words
The arrangement of claim 24 wherein said alarm means includes a fluid driven motor alarm which is actuated by fluid supplied downstream of said alarm valve, when said alarm valve is open.
Claim 32
Dependent Claim
32 words
The arrangement of claim 27 wherein said alarm means includes a fluid driven motor alarm which is actuated by fluid supplied downstream of said alarm valve, when said alarm valve is open.
Claim 33
Dependent Claim
36 words
The arrangement of claim 24 wherein said first check valve, said alarm valve and said means for providing fluid communication between said first check valve and said alarm valve are all provided within a common housing.
Claim 34
Dependent Claim
84 words
The arrangement of claim 24 wherein said first check valve and said means for providing fluid communication between said first check valve and said alarm valve through a passageway are provided within a common housing, said common housing having an inlet and an outlet, said inlet including means for coupling said housing to said main conduit and said outlet including means for coupling said common housing to said alarm valve, said inlet and said outlet being oriented substantially linearly with respect to one another.
Claim 35
Dependent Claim
56 words
The arrangement of claim 31 wherein said common housing is oriented vertically with said passageway within said common housing providing a first portion which is oriented generally upwardly from said inlet to said first check valve and a second portion which is oriented generally downwardly and then upwardly from said first check valve to said outlet.
Claim 36
Dependent Claim
81 words
The arrangement of claim 24 wherein said plumbing fitting has an inlet and an outlet, said inlet including said means for coupling said fitting to said first check valve and said outlet including said means for coupling said fitting to said alarm valve, said inlet and said outlet being oriented generally linearly with respect to one another with said plumbing fitting being oriented generally horizontally, said plumbing fitting including a mid-portion which is vertically lower than said inlet and said outlet.
Claim 37
Dependent Claim
70 words
The arrangement of claim 24 wherein said plumbing fitting has an inlet and an outlet, said inlet including said means for coupling said fitting to said first check valve and said outlet including said means for coupling said fitting to said alarm valve, said inlet and said outlet being oriented at 90 degrees with respect to one another, said conduit including a mid-portion which is vertically lower than said inlet.
Claim 38
Dependent Claim
39 words
The arrangement of claim 34 wherein said outlet is vertically lower than said inlet, with a lowermost portion of a seat of said alarm valve being lower than a lowermost portion of a seat of said first check valve.
Claim 39
Dependent Claim
15 words
The arrangement of claim 32 wherein said first check valve is a stop check valve.
Claim 40
Dependent Claim
175 words
A combined alarm valve and backflow prevention arrangement for a fire suppression sprinkler system, having a main conduit and an arrangement of individual sprinklers downstream of the main conduit, said combined alarm valve and backflow prevention arrangement comprising: a first check valve provided in said main conduit upstream of said arrangement of individual sprinklers; an alarm valve formed by a second check valve provided in said main conduit downstream of said first check valve and upstream of said arrangement of individual sprinklers; alarm means for indicating when the second check valve is open; and means for providing fluid communication between said first check valve and said alarm valve through a passageway; means for draining the passageway between said first check valve and said alarm valve in response to the pressure in said main conduit; whereby said first check valve and said alarm valve provide a reduced pressure zone, double check valve backflow prevention and alarm arrangement for a fire suppression system with no stop valves provided between said first check valve and said alarm valve.
Claim 41
Dependent Claim
175 words
A combined alarm valve and backflow prevention arrangement for a fire suppression sprinkler system, having a main conduit and an arrangement of individual sprinklers downstream of the main conduit, said combined alarm valve and backflow prevention arrangement comprising: a first check valve provided in said main conduit upstream of said arrangement of individual sprinklers; an alarm valve formed by a second check valve provided in said main conduit downstream of said first check valve and upstream of said arrangement of individual sprinklers; alarm means for indicating when the second check valve is open; and means for providing fluid communication between said first check valve and said alarm valve through a passageway; means for draining the passageway between said first check valve and said alarm valve in response to the pressure in said main conduit; whereby said first check valve and said alarm valve provide a reduced pressure zone, double check valve backflow prevention and alarm arrangement for a fire suppression system with no stop valves provided between said first check valve and said alarm valve.
Claim 42
Dependent Claim
63 words
The arrangement of claim 37 wherein the means for providing communication between said first check valve and said alarm valve comprises a plumbing fitting, said plumbing fitting comprising: a conduit having means for coupling said plumbing fitting to the first check valve upstream of the plumbing fitting and means for coupling said plumbing fitting to the alarm valve downstream of the plumbing fitting.
Claim 43
Dependent Claim
13 words
The arrangement of claim 38 wherein the first check valve is spring loaded.
Claim 44
Dependent Claim
57 words
The arrangement of claim 38 wherein said conduit has an inlet and an outlet, said inlet including said means for coupling said fitting to said first check valve and said outlet including said means for coupling said fitting to said alarm valve, said inlet and said outlet being oriented at 90 degrees with respect to one another.
Claim 45
Dependent Claim
36 words
The arrangement of claim 37 wherein said first check valve, said alarm valve and said means for providing fluid communication between said first check valve and said alarm valve are all provided within a common housing.
Claim 46
Dependent Claim
84 words
The arrangement of claim 37 wherein said first check valve and said means for providing fluid communication between said first check valve and said alarm valve through a passageway are provided within a common housing, said common housing having an inlet and an outlet, said inlet including means for coupling said housing to said main conduit and said outlet including means for coupling said common housing to said alarm valve, said inlet and said outlet being oriented substantially linearly with respect to one another.
Claim 47
Dependent Claim
15 words
The arrangement of claim 42 wherein said first check valve is a stop check valve.
Claim 48
Dependent Claim
203 words
A combined alarm valve and backflow prevention arrangement for a fire suppression sprinkler system, having a main conduit and an arrangement of individual sprinklers downstream of the main conduit, said combined alarm valve and backflow prevention arrangement comprising: a first check valve provided in said main conduit upstream of said arrangement of individual sprinklers, said first check valve being spring-biased; an alarm valve formed by a second check valve provided in said main conduit downstream of said first check valve and upstream of said arrangement of individual sprinklers, said second check valve being spring-biased; alarm means for indicating when the second check valve is open; means for providing fluid communication between said first check valve and said alarm valve through a passageway; means for draining the passageway between said first check valve and said alarm valve in response to the pressure in said main conduit; and test port means for testing said alarm valve and said first check valve as a reduced pressure zone, double check valve backflow prevention and alarm valve arrangement, said test port means including test ports provided immediately upstream of the first check valve, downstream of the alarm valve and between said first check valve and said alarm valve.
Claim 49
Dependent Claim
203 words
A combined alarm valve and backflow prevention arrangement for a fire suppression sprinkler system, having a main conduit and an arrangement of individual sprinklers downstream of the main conduit, said combined alarm valve and backflow prevention arrangement comprising: a first check valve provided in said main conduit upstream of said arrangement of individual sprinklers, said first check valve being spring-biased; an alarm valve formed by a second check valve provided in said main conduit downstream of said first check valve and upstream of said arrangement of individual sprinklers, said second check valve being spring-biased; alarm means for indicating when the second check valve is open; means for providing fluid communication between said first check valve and said alarm valve through a passageway; means for draining the passageway between said first check valve and said alarm valve in response to the pressure in said main conduit; and test port means for testing said alarm valve and said first check valve as a reduced pressure zone, double check valve backflow prevention and alarm valve arrangement, said test port means including test ports provided immediately upstream of the first check valve, downstream of the alarm valve and between said first check valve and said alarm valve.
Claim 50
Dependent Claim
63 words
The arrangement of claim 44 wherein the means for providing communication between said first check valve and said alarm valve comprises a plumbing fitting, said plumbing fitting comprising: a conduit having means for coupling said plumbing fitting to the first check valve upstream of the plumbing fitting and means for coupling said plumbing fitting to the alarm valve downstream of the plumbing fitting.
Claim 51
Dependent Claim
27 words
The arrangement of claim 44 wherein said first check valve has a valve member and a valve seat, and wherein the first check valve is spring loaded.
Claim 52
Dependent Claim
32 words
The arrangement of claim 46 wherein said means for providing fluid communication includes means for admitting air into the passageway when the pressure in the passageway falls below a first predetermined amount.
Claim 53
Dependent Claim
57 words
The arrangement of claim 45 wherein said conduit has an inlet and an outlet, said inlet including said means for coupling said fitting to said first check valve and said outlet including said means for coupling said fitting to said alarm valve, said inlet and said outlet being oriented at 90 degrees with respect to one another.
Claim 54
Dependent Claim
34 words
The arrangement of claim 44 wherein said alarm means includes a fluid driven motor alarm which is actuated by fluid supplied downstream of said second check valve, when said second check valve is open.
Claim 55
Dependent Claim
36 words
The arrangement of claim 44 wherein said first check valve, said alarm valve and said means for providing fluid communication between said first check valve and said alarm valve are all provided within a common housing.
Claim 56
Dependent Claim
84 words
The arrangement of claim 44 wherein said first check valve and said means for providing fluid communication between said first check valve and said alarm valve through a passageway are provided within a common housing, said common housing having an inlet and an outlet, said inlet including means for coupling said housing to said main conduit and said outlet including means for coupling said common housing to said alarm valve, said inlet and said outlet being oriented substantially linearly with respect to one another.
Claim 57
Dependent Claim
56 words
The arrangement of claim 51 wherein said common housing is oriented vertically with said passageway within said common housing providing a first portion which is oriented generally upwardly from said inlet to said first check valve and a second portion which is oriented generally downwardly and then upwardly from said first check valve to said outlet.
Claim 58
Dependent Claim
15 words
The arrangement of claim 52 wherein said first check valve is a stop check valve.
Claim 59
Dependent Claim
26 words
The arrangement of claim 1 wherein said alarm valve is provided with pressure gauge and test ports immediately upstream and downstream of the second check valve.
Claim 60
Dependent Claim
26 words
The arrangement of claim 24 wherein said alarm valve is provided with pressure gauge and test ports immediately upstream and downstream of the second check valve.
Claim 61
Dependent Claim
26 words
The arrangement of claim 37 wherein said alarm valve is provided with pressure gauge and test ports immediately upstream and downstream of the second check valve.
Claim 62
Dependent Claim
29 words
The arrangement of claim 44 wherein said first check valve is a stop check valve and wherein said second check valve is a swing check valve for riser pipe.
Claim 63
Dependent Claim
34 words
The arrangement of claim 1 wherein said alarm means includes an electrically triggered alarm which is actuated by a flow switch downstream of said second check valve, when said second check valve is open.
Claim 64
Dependent Claim
28 words
The arrangement of claim 58 wherein said second check valve is a swing check valve for riser pipe and wherein the flow switch is a paddle flow switch.
Claim 65
Dependent Claim
34 words
The arrangement of claim 24 wherein said alarm means includes an electrically triggered alarm which is actuated by a flow switch downstream of said second check valve, when said second check valve is open.
Claim 66
Dependent Claim
28 words
The arrangement of claim 60 wherein said second check valve is a swing check valve for riser pipe and wherein the flow switch is a paddle flow switch.
Claim 67
Dependent Claim
34 words
The arrangement of claim 37 wherein said alarm means includes an electrically triggered alarm which is actuated by a flow switch downstream of said second check valve, when said second check valve is open.
Claim 68
Dependent Claim
28 words
The arrangement of claim 62 wherein said second check valve is a swing check valve for riser pipe and wherein the flow switch is a paddle flow switch.
Claim 69
Dependent Claim
34 words
The arrangement of claim 44 wherein said alarm means includes an electrically triggered alarm which is actuated by a flow switch downstream of said second check valve, when said second check valve is open.
Claim 70
Dependent Claim
28 words
The arrangement of claim 64 wherein said second check valve is a swing check valve for riser pipe and wherein the flow switch is a paddle flow switch.
Claim 71
Dependent Claim
35 words
The arrangement of claim 1 further comprising an impeller flow sensor and meter means for recording a flow through the first check valve, the impeller flow sensor being provided adjacent to the first check valve.
Claim 72
Dependent Claim
35 words
The arrangement of claim 24 further comprising an impeller flow sensor and meter means for recording a flow through the first check valve, the impeller flow sensor being provided adjacent to the first check valve.
Claim 73
Dependent Claim
35 words
The arrangement of claim 37 further comprising an impeller flow sensor and meter means for recording a flow through the first check valve, the impeller flow sensor being provided adjacent to the first check valve.
Claim 74
Dependent Claim
35 words
The arrangement of claim 44 further comprising an impeller flow sensor and meter means for recording a flow through the first check valve, the impeller flow sensor being provided adjacent to the first check valve.
Claim 75
Dependent Claim
22 words
The arrangement of claim 66 further comprising: means for remotely indicating the flow through the combined alarm valve and backflow prevention arrangement.
Claim 76
Dependent Claim
22 words
The arrangement of claim 67 further comprising means for remotely indicating the flow through the combined alarm valve and backflow prevention arrangement.
Claim 77
Dependent Claim
22 words
The arrangement of claim 68 further comprising means for remotely indicating the flow through the combined alarm valve and backflow prevention arrangement.
Claim 78
Dependent Claim
22 words
The arrangement of claim 69 further comprising means for remotely indicating the flow through the combined alarm valve and backflow prevention arrangement.
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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) | 1994-02-11 | 1994-08-13 | 1995-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-11 | 1998-08-13 | 1999-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-11 | 2002-08-13 | 2003-02-12 | $7700.00 | Window Closed / Lapsed |