US3638211A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crane safety system
Assignee: Northrop Grumman Guidance and Electronics Co Inc
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Filing: 1969-10-08
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Granted: 1972-01-25
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Expires: 1989-10-08
Abstract
Abstract A system is shown for warning the operator of a crane when the crane is about to overturn due to the moment of a heavy load or when the weight of that load could cause structural failure of the crane. Sensors for measuring the boom length, boom angle, condition of the crane support, and the quadrant in which the crane is operating are connected to the crane and apply signals to a computer which selects previously stored information from a memory unit depending on the signals received. This stored information is applied to a comparator which compares the stored signal against a measured load signal and provides a warning alarm to the crane operator when the two signals approach each other.
Inventors
- 👤 Albert A Sanchez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:51
CPC Classifications
B; B66; B66C; B66C23/00; B66C23/88; B66C23/90; B66C23/905
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
170 words
A crane safety system for use within a crane having a loadlifting boom structure, comprising: boom length sensor means for sensing the length of the boom structure; boom angle sensor means for sensing the vertical angular relation of the axis of said boom structure to a horizontal plane; digital memory means for storing information peculiar to said crane; means connecting said boom angle sensor means and said boom length sensor means to said digital memory means for addressing signals thereto; said digital memory means receiving said addressed signals from said sensor means and selecting a portion of said stored information determined by said addressed signals as a selected output signal; boom load-sensing means for generating a measured load signal; comparator means connected to said boom load-sensing means and said digital memory means for comparing said measured load signal and said selected portion of said stored information output signal; and alarm means connected to said comparator means for producing an alarm when said load signal approaches said stOred information output signal.
Claim 2
Dependent Claim
170 words
A crane safety system for use within a crane having a loadlifting boom structure, comprising: boom length sensor means for sensing the length of the boom structure; boom angle sensor means for sensing the vertical angular relation of the axis of said boom structure to a horizontal plane; digital memory means for storing information peculiar to said crane; means connecting said boom angle sensor means and said boom length sensor means to said digital memory means for addressing signals thereto; said digital memory means receiving said addressed signals from said sensor means and selecting a portion of said stored information determined by said addressed signals as a selected output signal; boom load-sensing means for generating a measured load signal; comparator means connected to said boom load-sensing means and said digital memory means for comparing said measured load signal and said selected portion of said stored information output signal; and alarm means connected to said comparator means for producing an alarm when said load signal approaches said stOred information output signal.
Claim 3
Dependent Claim
41 words
A crane safety system as claimed in claim 1, wherein, said stored information includes maximum safe load in the form of digital stress information, and said measured load signal is generated by a strain-sensitive device in the form of stress signals.
Claim 4
Dependent Claim
86 words
A crane safety system as claimed in claim 2 wherein said crane includes a gantry hard line connecting said boom structure to a gantry strut and wherein said strain-sensitive device for generating said measured load stress signal, comprises, circuit means including a plurality of strain gages, connecting means for connecting said gantry hard line to said gantry strut, and said circuit means including a plurality of strain gages mounted upon said connecting means for sensing the strain therein and for generating said measured load stress signals.
Claim 5
Dependent Claim
42 words
A crane safety system as claimed in claim 3 wherein said connecting means includes a pin and clevis, said pin is formed from a tubular member, and said plurality of strain gages are mounted upon the inner surface of said tubular member.
Claim 6
Dependent Claim
150 words
A crane safety system as claimed in claim 1, wherein said digital memory means additionally comprises: stored information within said digital memory means including digital values of various boom angles and digital values of maximum load in the form of stress at each of said various boom angles; control means including clock means connecting said boom length sensor means to said memory means for sequentially addressing said memory means and receiving said selected portions of said stored information including said digital values of various boom angles; process means including said clock means connecting said boom angle sensor means to said memory means for matching said sensed boom angle with the stored digital value of various boom angles and selecting a stored information signal representing said digital values of maximum load at said sensed boom angle; wherein said stored digital value of maximum load is compared with said measured load signal.
Claim 7
Dependent Claim
34 words
A crane safety system as claimed in claim 1, additionally comprising, further sensor means for sensing the support condition of said crane connected to said digital memory means for selecting said stored information therefrom.
Claim 8
Dependent Claim
48 words
A crane safety system as claimed in claim 1, wherein, said alarm means connected to said comparator means includes a first alarm which alarms as said measured load signal approaches said stored information and a second alarm which alarm as said measured load signal equals said stored information.
Claim 9
Dependent Claim
127 words
A crane safety system for warning the operator of a pending crane failure, comprising: sensor means for sensing a plurality of crane conditions and generating information signals in response thereto; memory means for storing information peculiar to said crane; selection means for selecting portions of said stored information from said memory means in response to said generated information signals received from said sensor means and for presenting said portions of said stored information as a stored information signal representing a particular crane function; further sensing means for actually measuring said particular crane function and generating an actual information signal; and means for comparing said actual information signal against said stored information signal and generating a warning signal as said actual and stored information signals approach each other.
Claim 10
Dependent Claim
127 words
A crane safety system for warning the operator of a pending crane failure, comprising: sensor means for sensing a plurality of crane conditions and generating information signals in response thereto; memory means for storing information peculiar to said crane; selection means for selecting portions of said stored information from said memory means in response to said generated information signals received from said sensor means and for presenting said portions of said stored information as a stored information signal representing a particular crane function; further sensing means for actually measuring said particular crane function and generating an actual information signal; and means for comparing said actual information signal against said stored information signal and generating a warning signal as said actual and stored information signals approach each other.
Claim 11
Dependent Claim
31 words
A crane safety system as claimed in claim 8, wherein, a said particular crane function presented by said selection means and sensed by said further sensing means is the crane load.
Claim 12
Dependent Claim
57 words
A crane safety system as claimed in claim 9, wherein said memory means stores the maximum crane load in the form of stress which said crane will support under said plurality of crane conditions for warning the operator thereof when the crane may fail due to a structure limitation or due to pending overturning of the craNe.
Claim 13
Dependent Claim
20 words
A crane safety system as claimed in claim 8, wherein, said memory means additionally comprise a digital read only memory.
Claim 14
Dependent Claim
93 words
A crane safety system for warning an operator of a pending crane failure while manipulating a load, comprising: memory means for storing information peculiar to a plurality of crane-operating conditions including the maximum load under each of said operating conditions; means for sending said plurality of crane-operating conditions and selecting the stored value of maximum load for the particular crane-operating condition sensed; and means for comparing said selected stored value of maximum load against said manipulated load and for producing a warning as said manipulated load approaches said stored value of maximum load.
Claim 15
Dependent Claim
93 words
A crane safety system for warning an operator of a pending crane failure while manipulating a load, comprising: memory means for storing information peculiar to a plurality of crane-operating conditions including the maximum load under each of said operating conditions; means for sending said plurality of crane-operating conditions and selecting the stored value of maximum load for the particular crane-operating condition sensed; and means for comparing said selected stored value of maximum load against said manipulated load and for producing a warning as said manipulated load approaches said stored value of maximum load.
References Cited (Backward Citations)
US3505514A
Cited
US3489294A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |