US4579098A
Expired / Lapsed
US
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Method of and device for controlling the burn-off of a measuring resistor
Assignee: Robert Bosch GmbH
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Filing: 1985-03-19
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Granted: 1986-04-01
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Expires: 2005-03-19
Abstract
Abstract Disclosed is a method of and a device for controlling a burn-off function of a measuring resistor, particularly heated wire or heated film in an air flow sensor of an internal combustion engine. The burn-off operation for fast cleaning the measuring resistor is normally made either periodically or in response to preset operational conditions of the engine. The invention interrupts this burn-off function when detrimental operational condition of the engine depending on the rotary speed has occurred. The stoppage of the burn-off function preferably occurs after a simultaneous detection of a predetermined temperature value detected by a sensor.
Inventors
- 👤 Bernhard Mattes
- 👤 Egbert Perenthaler
- 👤 Gunther Plapp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:09
CPC Classifications
G; G01; G01F; G01F15/00; G01F15/12; F; F02; F02D; F02D41/00; F02D41/02; F02D41/18; F02D41/187; G01F1/00; G01F1/68; G01F1/696; G01F1/698; G01F1/6983
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
96 words
A device for controlling the burn-off of a measuring resistor such as a heated wire or heated cell, particularly, for stopping the burn-off function of a control circuit for a measuring resistor arranged as an air mass flow sensor of an internal combustion engine, comprising means for producing a rotary speed signal, at least one timing member responsive to a predetermined limit value of the rotary speed signal to produce a trigger signal, storage means triggered by said trigger signal to generate an output signal applied to said burn-off control circuit for stopping its burn-off operation.
Claim 2
Independent Claim
96 words
A device for controlling the burn-off of a measuring resistor such as a heated wire or heated cell, particularly, for stopping the burn-off function of a control circuit for a measuring resistor arranged as an air mass flow sensor of an internal combustion engine, comprising means for producing a rotary speed signal, at least one timing member responsive to a predetermined limit value of the rotary speed signal to produce a trigger signal, storage means triggered by said trigger signal to generate an output signal applied to said burn-off control circuit for stopping its burn-off operation.
Claim 3
Dependent Claim
95 words
A device as defined in claim 1, comprising two timing members in the form of monostable multivibrators whose inputs are connected to the source of the rotary speed signal, said storage means being in the form of a RS flip-flop latch whose R and S inputs are connected via gating means to the corresponding outputs of said multivibrators, an end stage controlled by the output signal at said RS flip-flop between a conductive and non-conductive stage, the output of said end stage being connected to said control circuit for stopping or starting its burn-off function.
Claim 4
Dependent Claim
87 words
A device as defined in claim 1, further comprising a switching temperature sensor of the engine which after falling below or exceeding a preset temperature value switches over its output signal, the output signal of said temperature sensor being applied to said end stage where it is combined with the ouptut signal of the RS flip-flop to activate or inactivate the end stage and hence to stop or release the burn-off control circuit when the two signals are simultaneously applied to or removed from the end stage.
Claim 5
Independent Claim
314 words
A device for controlling the burn-off of a measuring resistor such as a heated wire or heated cell, particularly for stopping the burn-off function of a cotnrol circuit for an air mass flow sensor of an internal combustion engine, comprising means for producing a rotary speed signal, at least one timing member responsive to a predetermined limit value of the rotary speed signal to produce a trigger signal, storage means triggered by said trigger signal to generate an output signal applied to said burn-off control circuit for stopping its burn-off operation, two timing members in the form of monostable multivibrators whose inputs are connected to the source of the rotary speed signal, said storage means being in the form of a RS flip-flop latch whose R and S inputs are connected via gating means to the corresponding outputs of said multivibrators, an end stage controlled by the output signal at said RS flip-flop between a conductive and non-conductive stage, the output of said end stage being connected to said control circuit for stopping or starting its burn-off function, and wherein the time interval of the non-stable state of a first monostable multivibrator is set shorter than the duration of a cycle of the rotary speed signal, the latter corresponding to a rotation of the engine to detect the drop below a lower value of the rotary speed signal in such a manner that in resetting the monostable multivibrator to its original state a setting pulse is generated for the subsequent storing RS flip-flop when ignition switch indicating signal Z simultaneously applied to the gating means and the time interval of the unstable state of the second monostable multivibrator is set to be longer than half wave of the rotary speed signal so that a reset pulse is applied to the RS storing flip-flop when the upper limit value of the rotary speed is exceeded.
Claim 6
Independent Claim
314 words
A device for controlling the burn-off of a measuring resistor such as a heated wire or heated cell, particularly for stopping the burn-off function of a cotnrol circuit for an air mass flow sensor of an internal combustion engine, comprising means for producing a rotary speed signal, at least one timing member responsive to a predetermined limit value of the rotary speed signal to produce a trigger signal, storage means triggered by said trigger signal to generate an output signal applied to said burn-off control circuit for stopping its burn-off operation, two timing members in the form of monostable multivibrators whose inputs are connected to the source of the rotary speed signal, said storage means being in the form of a RS flip-flop latch whose R and S inputs are connected via gating means to the corresponding outputs of said multivibrators, an end stage controlled by the output signal at said RS flip-flop between a conductive and non-conductive stage, the output of said end stage being connected to said control circuit for stopping or starting its burn-off function, and wherein the time interval of the non-stable state of a first monostable multivibrator is set shorter than the duration of a cycle of the rotary speed signal, the latter corresponding to a rotation of the engine to detect the drop below a lower value of the rotary speed signal in such a manner that in resetting the monostable multivibrator to its original state a setting pulse is generated for the subsequent storing RS flip-flop when ignition switch indicating signal Z simultaneously applied to the gating means and the time interval of the unstable state of the second monostable multivibrator is set to be longer than half wave of the rotary speed signal so that a reset pulse is applied to the RS storing flip-flop when the upper limit value of the rotary speed is exceeded.
Claim 7
Independent Claim
137 words
A method of controlling the burn-off of a temperature measuring resistor such as a heated wire installed in the intake manifold of an internal combustion engine and connected to a source of measuring electric current, the engine being equipeed with means for performing in predetermined time intervals the burn-off function by heating the measuring resistor with an electric current of increased intensity with respect to the measuring electric current, comprising the steps of detecting a critical rotary speed value of the engine at which catalytic burning of the measuring resistor may occur, measuring rotary speed of the engine during operation of said means for performing the burn off function, and stopping the operation of said burn-off performing means by the aid of an electric protective circuit in response to the detection of said critical rotary speed value.
Claim 8
Independent Claim
137 words
A method of controlling the burn-off of a temperature measuring resistor such as a heated wire installed in the intake manifold of an internal combustion engine and connected to a source of measuring electric current, the engine being equipeed with means for performing in predetermined time intervals the burn-off function by heating the measuring resistor with an electric current of increased intensity with respect to the measuring electric current, comprising the steps of detecting a critical rotary speed value of the engine at which catalytic burning of the measuring resistor may occur, measuring rotary speed of the engine during operation of said means for performing the burn off function, and stopping the operation of said burn-off performing means by the aid of an electric protective circuit in response to the detection of said critical rotary speed value.
Claim 9
Dependent Claim
27 words
A method as defined in claim 5 wherein said measuring resistor is a part of an air-mass flow sensor installed in an intake manifold of the engine.
Claim 10
Dependent Claim
23 words
A method as defined in claim 5, wherein the burn-off function is interrupted when the temperature of the engine drops below 20° centigrade.
Claim 11
Dependent Claim
64 words
A method as defined in claim 5, wherein the burn-off function is stopped when a detected upper value of the rotary speed has not been exceeded since the last turn-on of the engine and/or at the turn on condition of the engine in which the ignition switch is on and the critical rotary speed of the engine has dropped below a detected lower value.
Claim 12
Dependent Claim
60 words
A method as defined in claim 8, and wherein a window defined by the lower rotary speed value and the upper rotary speed value is generated by means for two timing members whose outputs are coupled to a bistable storage device, the output signal of which determines the rotary speed window during which said burn-off function producing means remain unaffected.
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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) | 1989-03-31 | 1989-09-30 | 1990-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-31 | 1993-09-30 | 1994-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-31 | 1997-09-30 | 1998-04-01 | $7700.00 | Window Closed / Lapsed |