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US4345539A Expired / Lapsed US ⏱️ 0.0 years remaining

Warning system with pneumatic function generator

Assignee: MI Drilling Fluids Co
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Filing: 1980-04-21
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Granted: 1982-08-24
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Expires: 2000-04-21
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Abstract

Abstract A totally pneumatic crane warning system is disclosed capable of use in oil well environments. The crane warning system utilizes a pneumatic function generator. The pneumatic function generator includes a means for receiving a linear pneumatic signal that may be representative of a boom angle and translating that signal to a non-linear output representative of the maximum load capacity of the crane at that angle. This function is accomplished through the use of a rolling cam machined to represent the functional relationship between the boom angle and the maximum load capacity at that angle. This relationship has been found to be non-linear in nature. A pneumatic control circuit is utilized in conjunction with the rolling cam to effect the pneumatic output signal that is representative of the maximum load capacity at a given boom angle. The crane warning system is further provided with a means for comparing the maximum load signal with the actual load of the crane and actuating a pneumatic warning device when the actual weight exceeds the maximum load capacity output of the function generator.

Inventors

  • 👤 Henry L. Williams

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 22:24
CPC Classifications
B; B66; B66C; B66C23/00; B66C23/88; B66C23/90; Y; Y10; Y10T; Y10T137/00; Y10T137/2278; Y10T137/8158

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 187 words
A pneumatic warning system for a boom-type load lifting device comprising: a pneumatic function generator including: an air cylinder with means for receiving and storing an input pneumatic signal; means for mechanically representing a predetermined curve, functionally dependent on said input pneumatic signal, mechanically connected to said air cylinder; and means for translating the function of said curve to an output pneumatic signal for any value of said input pneumatic signal, mechanically connected to and operatively associated with said means for representing said curve; means for transmitting a boom angle pneumatic signal, pneumatically connected to said pneumatic function generator; means for determining the weight of a load on said lifting device; means for delivering a pneumatic load signal to said pneumatic function generator, comparator signal means for comparing said output signal of said pneumatic function generator with said pneumatic load signal, whereby said comparator means delivers a pneumatic output warning signal when said load signal exceeds said pneumatic function generator output signal; and warning signal means connected to said comparator signal means for sounding a warning when said load signal exceeds said pneumatic function generator output signal.
Claim 2
Dependent Claim 187 words
A pneumatic warning system for a boom-type load lifting device comprising: a pneumatic function generator including: an air cylinder with means for receiving and storing an input pneumatic signal; means for mechanically representing a predetermined curve, functionally dependent on said input pneumatic signal, mechanically connected to said air cylinder; and means for translating the function of said curve to an output pneumatic signal for any value of said input pneumatic signal, mechanically connected to and operatively associated with said means for representing said curve; means for transmitting a boom angle pneumatic signal, pneumatically connected to said pneumatic function generator; means for determining the weight of a load on said lifting device; means for delivering a pneumatic load signal to said pneumatic function generator, comparator signal means for comparing said output signal of said pneumatic function generator with said pneumatic load signal, whereby said comparator means delivers a pneumatic output warning signal when said load signal exceeds said pneumatic function generator output signal; and warning signal means connected to said comparator signal means for sounding a warning when said load signal exceeds said pneumatic function generator output signal.
Claim 3
Dependent Claim 36 words
A pneumatic warning system as set forth in claim 1 wherein said means for transmitting a boom angle pneumatic signal comprises a pneumatic transmitter capable of delivering a predetermined pneumatic signal at a given boom angle.
Claim 4
Dependent Claim 28 words
A pneumatic warning system as set forth in claim 1 wherein said means for determining the weight of said load on said lifting device comprises a load cell.
Claim 5
Dependent Claim 16 words
A pneumatic warning system as set forth in claim 3 wherein said load cell is hydraulic.
Claim 6
Dependent Claim 16 words
A pneumatic warning system as set forth in claim 3 wherein said load cell is pneumatic.
Claim 7
Dependent Claim 56 words
A pneumatic warning system as set forth in claim 4 wherein said means for delivering a pneumatic load signal is a hydraulic to pneumatic transducer having a means for receiving a referenced air supply and said hydraulic load signal from said hydraulic load cell, and delivering a pneumatic signal indicative of the weight of said load.
Claim 8
Dependent Claim 20 words
A pneumatic warning system as set forth in claim 1 wherein said comparator signal means is a differential pressure switch.
Claim 9
Dependent Claim 20 words
A pneumatic warning system as set forth in claim 1 further including a pneumatic relay for boosting said warning signal.
Claim 10
Dependent Claim 19 words
A pneumatic warning system as set forth in claim 1 wherein said warning signal means comprises a pneumatic horn.
Claim 11
Dependent Claim 38 words
A pneumatic warning system as set forth in claim 1 further including a biasing air regulator pneumatically connected to said means for transmitting a boom angle pneumatic signal, for changing said boom angle signal with varying boom length.
Claim 12
Dependent Claim 29 words
A pneumatic warning system as set forth in claim 1 further including first and second pneumatic gauges for indicating the maximum capacity and actual load, and boom angle respectively.
Claim 13
Dependent Claim 21 words
A pneumatic warning system as set forth in claim 1 further including a pneumatic switch for deactivating said warning signal means.

References Cited (Backward Citations)

DE632356C Cited
US2222551A Cited
US3018041A Cited
US2967537A Cited
US3239140A Cited
US3254837A Cited
US3278925A Cited
US3491229A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-08-23 1986-02-22 1986-08-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-08-23 1990-02-22 1990-08-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-08-23 1994-02-22 1994-08-24 $7700.00 Window Closed / Lapsed

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