US3776200A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic self-testing low-water cut-off
Assignee: Watts Regulator Co
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Filing: 1972-09-01
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Granted: 1973-12-04
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Expires: 1992-09-01
Abstract
Abstract A system for preventing ''''dry-boiler'''' failures which includes a float mechanism for detecting the water level in a heated reservoir and a device for testing the float mechanism to determine if it is operating properly and for preventing activation of the burner if improper operation is detected. If the float mechanism is operating properly but the water level is below a pre-determined safety level, then activation of the burner can be prevented and various alarms actuated to notify the operator.
Inventors
- 👤 S Tine
- 👤 C Rushforth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:01
CPC Classifications
F; F22; F22B; F22B37/00; F22B37/02; F22B37/42; F22B37/425
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
115 words
In a low-water cut-off control apparatus, for use in systems having a water reservoir and a water heater, said apparatus including float means mounted on a linkage surrounded by a protective bellows for detecting the water level in said reservoir and means operatively associated with said float for preventing activation of the water heater when the water level in the reservoir is below a predetermined safety level, the improvement which comprises said control apparatus having test means associated with said float means, linkage, bellows and heater for urging said float means downwardly and for preventing activation of said heater if said linkage or said bellows is inoperative, thereby preventing free movement of said float means.
Claim 2
Dependent Claim
115 words
In a low-water cut-off control apparatus, for use in systems having a water reservoir and a water heater, said apparatus including float means mounted on a linkage surrounded by a protective bellows for detecting the water level in said reservoir and means operatively associated with said float for preventing activation of the water heater when the water level in the reservoir is below a predetermined safety level, the improvement which comprises said control apparatus having test means associated with said float means, linkage, bellows and heater for urging said float means downwardly and for preventing activation of said heater if said linkage or said bellows is inoperative, thereby preventing free movement of said float means.
Claim 3
Dependent Claim
33 words
An apparatus as in claim 1 wherein said test means include means for applying a force to said linkage and means for preventing activation of said burner of a predetermined force is exceeded.
Claim 4
Dependent Claim
103 words
An apparatus as in claim 2 wherein said force applying means include cam means; and spring-biased exerciser means operatively associated with said cam means and said float linkage means, said exerciser means including cam follower means, linkage-engaging means and spring means disposed therebetween which permit relative movement of said cam follower means and linkage-engaging means if said predetermined force is exceeded, said exerciser means also including means for detecting relative movement of cam follower means and linkage-engaging means toward each other and for preventing activation of said heater when said relative movement exceeds a predetermined distance which is related to said predetermined force.
Claim 5
Dependent Claim
81 words
An apparatus as in claim 3 wherein micro-switch means are mounted to said cam follower and stop plate means are mounted to said linkage-engaging means in spaced and aligned relation to said micro-switch means, said switch means and said plate means being engageable after said linkage-engaging means and said cam follower move said predetermined distance, said switch means associated with said burner and being normally closed and being movable to an open, activation-preventing position when in engagEment with said stop plate.
Claim 6
Dependent Claim
34 words
An apparatus as in claim 1 wherein there is further provided means associated with said float and said burner for preventing activation of said burner if said float is below a predetermined danger position.
Claim 7
Dependent Claim
30 words
An apparatus as in claim 5 wherein there is further provided alarm means operatively associated with said float for alerting an operator when said float is below the danger position.
Claim 8
Dependent Claim
33 words
An apparatus as in claim 5 including burner-activating means associated with said test means and float level means for activating said burner if said test means and said float means are operating properly.
Claim 9
Dependent Claim
45 words
An apparatus as in claim 7 wherein said test means include cam means having lobes thereon for exercising said float linkage and said burner activator means include cam means having lobe means arranged to permit activation of said burner after test means have been exercised.
Claim 10
Dependent Claim
24 words
An apparatus as in claim 6 wherein there is provided means for preventing activation of said alarm means during testing of said linkage means.
Claim 11
Dependent Claim
29 words
An apparatus as in claim 8 wherein there is further provided motor means for driving said cam means and means for deactivating said motor after said burner is activated.
Claim 12
Dependent Claim
25 words
An apparatus as in claim 10 wherein means are provided for reactivating said motor after said burner is deactivated if said motor is operating properly.
Claim 13
Dependent Claim
39 words
An apparatus as in claim 11 wherein means associated with said burner activator cam means, other than said activating lobe means, are positioned to reactivate said burner after deactivation thereof and prior to the activation of said test means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-03 | 1977-06-04 | 1977-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-03 | 1981-06-04 | 1981-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-03 | 1985-06-04 | 1985-12-04 | $7700.00 | Window Closed / Lapsed |