US3870226A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compaction of a surface with a compactor having wheels
Assignee: Richier SA
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Filing: 1973-05-21
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Granted: 1975-03-11
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Expires: 1993-05-21
Abstract
Abstract A device for continuously measuring a signal which varies as a hyperbolic or exponential function comprising an analog circuit having two signal input terminals, one of which is connected to a first signal source representative of at least one variable of the function to be measured and the other of which is connected to a second signal source representative of a second variable of the hyperbolic or exponential function. The analog circuit is so arranged that an output signal therefrom is proportional to the signal to be measured. A particular application of the device is in controlling a compactor in such a manner as to obtain a continuous control of the quality of compaction of a material. In this case the first signal source provides a signal representative of the torque applied to the wheels of the compactor and the second signal source provides a signal proportional to the movement of the compactor.
Inventors
- 👤 Maurice Leroy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:21
CPC Classifications
G; G06; G06J; G06J1/00
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
76 words
A method for determining the degree of compaction of a surface by means of a compactor having wheels, in successive sweeps, comprising the steps of: A. determining a value representative of the torque applied to the wheels of the compactor during at least a part of each sweep; B. comparing the value determined during two successive sweeps, and C. determining the degree of compaction of the surface as a function of the result of the comparison.
Claim 2
Independent Claim
76 words
A method for determining the degree of compaction of a surface by means of a compactor having wheels, in successive sweeps, comprising the steps of: A. determining a value representative of the torque applied to the wheels of the compactor during at least a part of each sweep; B. comparing the value determined during two successive sweeps, and C. determining the degree of compaction of the surface as a function of the result of the comparison.
Claim 3
Dependent Claim
81 words
A method according to claim 1 wherein the step determining a value representative of the torque applied to the wheels of the compactor during at Least a part of each sweep comprises the steps of: A. determining a value representative of the instantaneous torque applied to the wheels; B. determining a value representative of the speed of the compactor; and C. computing the average value of the torque applied to the wheels of the compactor during said part of each sweep.
Claim 4
Independent Claim
75 words
A device for determining the degree of compaction of a surface by a compactor having wheels, in successive sweeps, which comprises: A. means for providing a signal representative of the torque applied to the wheels during at least a part of each sweep; B. means for comparing the signals provided during two successive sweeps, and C. means for determining the degree of compaction as a function of the result of the comparison of said signals.
Claim 5
Independent Claim
75 words
A device for determining the degree of compaction of a surface by a compactor having wheels, in successive sweeps, which comprises: A. means for providing a signal representative of the torque applied to the wheels during at least a part of each sweep; B. means for comparing the signals provided during two successive sweeps, and C. means for determining the degree of compaction as a function of the result of the comparison of said signals.
Claim 6
Independent Claim
75 words
A device for determining the degree of compaction of a surface by a compactor having wheels, in successive sweeps, which comprises: A. means for providing a signal representative of the torque applied to the wheels during at least a part of each sweep; B. means for comparing the signals provided during two successive sweeps, and C. means for determining the degree of compaction as a function of the result of the comparison of said signals.
Claim 7
Independent Claim
75 words
A device for determining the degree of compaction of a surface by a compactor having wheels, in successive sweeps, which comprises: A. means for providing a signal representative of the torque applied to the wheels during at least a part of each sweep; B. means for comparing the signals provided during two successive sweeps, and C. means for determining the degree of compaction as a function of the result of the comparison of said signals.
Claim 8
Dependent Claim
88 words
A device according to claim 3 wherein said means for providing a signal representative of the torque applied to the wheels during at least a part of each sweep comprises: A. means for providing a signal representative of the instantanious torque applied to the wheels of the compactor; B. means for providing a signal representative of the speed of the compactor; and C. an analog circuit for producing an output signal representative of the torque applied to the wheels of the compactor during said part of each sweep.
Claim 9
Dependent Claim
140 words
A device according to claim 4, wherein the speed signal is a pulse signal, and wherein the analog circuit comprises: A. a frequency-potential converter for converting the pulses of said speed signal to an analog signal; B. a multiplier having two inputs and an output, one of said two inputs being connected to receive said instantaneous torque signal and the other of said two inputs being connected to receive said analog signal; C. a potential-frequency converter having an input which is coupled to said multiplier output, and D. at least one circuit coupled to said potential-frequency converter for converting an output signal therefrom into a signal the frequency of which is solely proportional to the absolute value of the potential of said signal representative of the torque applied to the wheels of the compactor during said part of each sweep.
Claim 10
Dependent Claim
29 words
A device according to claim 5, further comprising an absolute value amplifier connected to said instantaneous torque signal providing means, and wherein said multiplier is coupled to said amplifier.
Claim 11
Dependent Claim
64 words
A device according to claim 6, wherein said analog circuit comprises means for producing an output signal representative of the average value of the torque, and further comprising means for treating said average value as a function of a predetermined threshold representative of the compacting to be obtained, and means for indicating operations to be carried out during the course of compacting said surface.
Claim 12
Dependent Claim
81 words
A device according to claim 7, wherein said means for treating comprises a sequence logic associated with an impulse counter and a subtractor capable of obtaining the difference between the impulses counted between two consecutive passes of the compactor, said counter and said subtractor each being associated with means adapted to enable the sign of the torque at the wheels to be taken into account; and further comprising a control logic for comparing said difference with that of a predetermined threshold.
Claim 13
Dependent Claim
43 words
A device as claimed in claim 8, wherein said subtractor is a five decade circuit, and further comprising an adder connected to three decades of said subtractor, said adder being capable of effecting the difference between the impulses counted between two successive sweeps.
Claim 14
Dependent Claim
50 words
A device according to claim 8, further comprising a first gate connected to said subtractor, a second gate having one input connected to said first gate, and a double bistable element connected to said sequence logic, said bistable element having an input connected to the output of said second gate.
Claim 15
Dependent Claim
89 words
A device according to claim 10, wherein said sequence lOgic comprises a decade counter connected to the output of a third gate, one input of said third gate being connected to an output of a binary decoder associated with said decade counter while the other input of said third gate is connected to receive timing impulses and two ''''exclusive OR'''' gates each connected to a separate output of said binary decoder a further output of which controls the transfer of the count from said impulse counter to said subtractor.
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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) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |