ENGINE OIL SYSTEM HEALTH
MONITORING USING OIL LEVEL SENSOR
FINAL OFFICE ACTION
This action is in response to the Applicant’s amendment of March 02, 2026.
CLAIMS
In the event that the determination of the status of the application as subject to AIA is incorrect, any correction of the statutory basis for the rejection will not be considered a new ground of rejection if the rationale supporting the rejection would be the same.
35 U.S.C. § 112
In view of the Applicant’s amendments to the claims and corresponding remarks, the rejection of claims 13, 19, and 20 under 35 U.S.C. 112(b) as set forth in the previous Office Action of Nov. 28, 2025 has been overcome.
35 U.S.C. § 101
In view of the Applicant’s amendments to the claims and corresponding remarks, the rejection of claims 17 - 20 under 35 U.S.C. 101 as set forth in the said previous Office Action has been overcome.
35 U.S.C. § 103
Claims 1 - 6, 8 - 14 and 17 - 21 are rejected under 35 U.S.C. 103 as being unpatentable over Hegemier et al. (5,273,134).
With respect to independent claim 1, Hegemier et al. set forth a method for determining engine oil system health, the method comprising:
determining with an oil lever sensor within an engine oil sump (col. 1, lines 50 - 57), an oil level (52 in Fig. 3) in the engine oil sump (13) of an engine ( 10);
determining an oil consumption rate of the engine based on a current oil volume (col. 2, lines 1 - 5);
determining a remaining useful oil volume (55 and 56 of Fig. 3 and col. 1, lines 55 - 58) based on the oil consumption rate and duty cycle data of the engine (50 in Fig. 3); and
generating an alert in response to the oil consumption rate being greater than a predetermined threshold, the alert comprising a command (actuate pump) to a controller associated with the engine to cause the engine to perform an action (57 and 59 in Fig. 3).
Hegemier et al. fail to set forth an engine oil consumption rate determination based on a time at which the oil was last replenished.
However, it would have been obvious to one having ordinary skill in the art armed with the Hegemier et al. teaching that determining an engine oil consumption rate will take into account a time at which the oil was last replenished.
The motivation being that Hegemier et al. set forth that the oil consumption rate is based on a beginning oil level (52) and an ending oil level (54). When the ending oil level is unsatisfactory (56), oil is replenished (57 or 59) to the sump from an external tank and the oil consumption rate determination is performed over. Thus, the determining of an engine oil consumption rate takes into account a time at which the oil was last replenished.
In addition, Hegemier et al. fail to explicitly set forth the added limitation that the remaining useful oil volume corresponds to a volume of oil in the engine oil sump that is above a low oil level below which the engine is unable to maintain a desired oil pressure.
However, it would have been obvious to one having ordinary skill in the art armed with the Hegemier et al. teaching to set the low oil level at a level where the engine would be unable to maintain a desired oil pressure at oil levels below this level.
The motivation being to prevent engine damage in that one having ordinary skill in the art would have the knowledge that when the engine oil level is very low, an engine can not maintain a desired oil pressure and thus operating an engine with such a low oil level would cause damage to the engine. Thus, one would have motivation to not operate an engine with such a low oil level and accordingly be alerted if the oil level reaches such a point.
With respect to claim 2, Hegemier et al. suggest the time at which the oil was last replenished (57 or 59) based on an increase in the current oil volume (52) relative to a previous oil volume (55).
With respect to claim 3, Hegemier et al. set forth determining the remaining useful oil volume (55) is further based on historical data of oil levels (52 and 54).
With respect to claim 4, Hegemier et al. fail to set forth that the alert is output to a user interface. However, it would have been obvious to one having skill in the art armed with the Hegemier et al. teaching to output the alert to a user interface. The motivation being to inform the user of the current operation conditions.
With respect to claim 5, Hegemier et al. set forth that the predetermined threshold corresponds to a deviation above an expected oil consumption rate (56 in Fig. 3).
With respect to claim 6, Hegemier et al. suggest that the duty cycle data comprises power output of the engine (50 in Fig. 3).
With respect to claim 8, Hegemier et al. suggest determining an estimated fill schedule for the oil (ie. the need for one injection or two injections; 57 and 59 in Fig. 3).
With respect to claim 9, Hegemier et al. fail to set forth that the estimated fill schedule comprises a date or range of dates at which the oil level is estimated to fall below a predetermined level. However, any measurement at which the oil level is below a predetermined level, oil replenishment takes place at that date and time. Thus, a date of replenishment is suggested.
With respect to claim 10, Hegemier et al. suggests that the predetermined level corresponds to the low oil level (56 in Fig. 3) in which for oil levels below this level, the engine is unable to maintain the desired oil pressure as discussed above in the rejection of claim 1.
With respect to independent claim 11, Hegemier et al. set forth a system for monitoring engine system oil health, the system comprising:
a user interface (50 of Fig. 3);
an oil sump (13) of an engine (10);
an oil level sensor (20) positioned within a portion of the oil sump for determining an oil level in the oil sump (col. 1, lines 50 - 57); and
a controller (23) configured to determine an oil fill schedule based on the oil level (col. 3, lines 17 - 28).
Hegemier et al. fail to explicitly set forth that the oil fill schedule includes a date or range of dates at which oil in the oil sump should be replenished as is claimed. However, it would have been obvious to one having ordinary skill in the art armed with the Hegemier et al. teaching that the oil fill schedule would include a date at which oil in the oil sump should be replenished.
The motivation being that Hegemier et al. set forth that when the oil level is low, an oil pump (24) adds oil to the oil sump (13) from an external oil reservoir (25). Thus, the date at which the oil sump should be replenished is the date of the measurement (col. 3, lines 17 - 28) or as soon thereafter as possible.
In addition, Hegemier et al. fail to explicitly set forth the added limitation of determining whether the oil consumption rate exceeds an expected oil consumption threshold during normal operation of the engine, and upon determining that the oil consumption rate exceeds the normal threshold, generating and outputting an alert to the user interface, wherein the alert is displayed on the user interface.
However, it would have been obvious to one having ordinary skill in the art armed with the Hegemier et al. teaching to determine if the oil consumption rate exceeds an expected oil consumption threshold during normal operation of the engine, and if so, display the findings as an alert on the user interface.
The motivation being that if the measured oil level is lower than the expected oil level for a given time period, one can assume that the oil consumption rate exceeds a normal consumption rate. If left unchecked, an increased oil consumption rate can lead to a low level of engine oil in the engine sump and ultimately to engine damage. Thus, one having ordinary skill would have motivation to monitor and determine oil consumption and to alert the operator of any such high oil consumption.
With respect to claim 12, Hegemier et al. set forth a temperature sensor for determining a temperature of the oil (see 53 in Fig. 3) in the oil sump, wherein the controller is configured to apply temperature compensation (see 54 in Fig. 3) to an output signal of the oil level sensor based on the temperature of the oil, wherein the controller applies temperature compensation to the output signal of the oil sensor level by normalizing the oil level output signal based on the determined temperature of the oil in the oil sump (col. 5, lines 20 - 32).
With respect to claim 13, Hegemier et al. set forth that the controller is configured to determine a remaining useful oil volume (see 55 in Fig. 3) based on duty cycle data (see 50 in Fig. 3) and an oil consumption rate (see 56 in Fig. 3), wherein the remaining useful oil volume corresponds to a volume of oil in the oil sump that is above a low oil level below which the engine is unable to maintain a desired oil pressure (see reasoning in above rejection of claim 1), and wherein the duty cycle data includes power output information of the engine over time (see 50 in Fig. 3).
With respect to claim 14, Hegemier et al. fail to explicitly set forth that the controller is configured to determine a time of last oil fill based on the oil level as claimed.
However, it would have been obvious to one having ordinary skill in the art armed with the Hegemier et al. teaching that the controller is “configured” to determine a time of last oil fill.
The motivation being that the controller is a microprocessor (23) and microprocessors have time stamps as to when an action (ie. activation of oil pump 24) is carried out.
With respect to independent claim 17, Hegemier et al. set forth a method for determining an estimated fill schedule for an engine oil system of a machine, the method comprising:
determining with an oil level sensor positioned within an engine sump of an engine, an oil level (52 in Fig. 3) in the engine sump (13) of an engine (10);
determining an oil volume in the engine sump based on the oil level (col. 1, lines 55 - 58);
determining, with a controller of the machine, an oil consumption rate of the engine based on the oil volume and a time since a last oil fill (col. 2, lines 1 - 5); and
determining a fill rate for the oil based on the oil consumption rate (57 and 59 in Fig. 3).
Hegemier et al. fail to explicitly set forth determining an estimated fill schedule for the oil as claimed.
However, it would have been obvious to one having ordinary skill in the art armed with the Hegemier et al. teaching that such a determination of an estimated fill schedule is completed by Hegemier et al.
The motivation being that from the determined oil level/volume/consumption rate, Hegemier et al. determines whether to activate one or two injections (57 and 59 in Fig. 3) in order to replenish the oil when the oil level is below a predetermined amount. This replenishment can be reasonably interpreted as the “estimated fill schedule” as claimed because the use of two injections will replenish the oil to a given level faster than the use of one injection.
Hegemier et al. fail to explicitly set forth the added limitation that the determining of the oil consumption rate of the engine is also based on historical oil volume.
However, it would have been obvious to one having ordinary skill in the art armed with the Hegemier et al. teaching that the determined oil consumption rate is also based on historical oil volume as claimed.
The motivation being that Hegemier et al set forth that the oil level is recorded over a period of time in order to determine the rate of oil consumption. Thus, the previously recorded oil levels, relative to the currently recorded oil level, is a historic oil volume.
With respect to claim 18, Hegemier et al. fail to set forth that the estimated fill schedule comprises a date or range of dates at which the oil level is estimated to fall below a predetermined level. However, any measurement at which the oil level is below a predetermined level, oil replenishment takes place at that date and time. Thus, a date of replenishment is suggested.
Furthermore, the added limitation that the predetermined level corresponds to a volume of oil in the engine sump that is above a low oil level below which the engine is unable to maintain a desired oil pressure would have been obvious to one having ordinary skill in the art as per the reasoning as set forth above in the rejection of claim 1.
With respect to claim 19, Hegemier et al. suggest that when oil replenishment takes place (57 and 59 in Fig. 3), the estimated fill schedule extrapolates oil consumption data over a current window of data points (52 -56 in Fig. 3).
With respect to claim 20, Hegemier et al. set forth that the process (Fig. 3) repeats (at 55) when conditions warrant wherein new measured values (data points) are used and old measured
values (data points) are no longer used.
With respect to claim 21, the subject matter thereof is deemed as being an intended use of the engine which does not further limit the method of claim 1.
Claim 16 is rejected under 35 U.S.C. 103 as being unpatentable over Hegemier et al. (5,273,134) in view of Bradford et al. (2016/0230625).
With respect to claim 16, Hegemier et al. fail to set forth that the oil level sensor is a capacitive oil level sensor.
However, Bradford et al. set forth an oil level sensor which is a capacitive oil level sensor.
As such, it would have been obvious to one having ordinary skill in the art armed with these teachings to use a capacitive oil lever sensor, as taught by Bradford et al. in the system of Hegemier et al.
The motivation being that a capacitive oil level sensor is a commonly used type of liquid level sensor for its simple design, low cost, and reliable results.
The Examiner notes that the added limitation of the engine being required to be an engine of a locomotive is interpreted as merely an intended use of the engine and does not further define the monitoring system to which the claimed invention is directed.
Allowable Subject Matter
Claim 15 is objected to as being dependent upon rejected base claim 11, but would be allowable if rewritten in independent form including all of the limitations of the base claim 11 because the prior art fails to teach or suggest that the threshold is a predetermined number of standard deviations above the expected oil consumption during normal operation of the engine.
Response To Arguments
The Applicant’s arguments pertaining to the rejection of independent claim 1 under 35 U.S.C. 103 have been considered but have not been found to be persuasive. The Applicant argues that the applied prior art of Hegemier et al. do not teach determining oil level in an engine oil sump. Instead, the Applicant argues that Hegemier et al. teach a float chamber in communication with the engine oil sump. The Examiner disagrees in that the engine oil sump holds the engine oil for the engine and, ultimately, any determination of oil level is with respect to the oil level in the sump.
The Examiner disagrees with the Applicant’s comments and assessment pertaining to independent claim 11 in that no agreement was reached during the interview that independent claim 11, as amended, overcomes the current rejection under 35 USC 103.
The Applicant’s argument that independent claim 17 distinguishes over the prior art of Hegemier et al. and overcomes the current rejection under 35 U.S.C. 103 for the same reasons as presented with respect to claim 1 has not been found to be persuasive for the same reasoning as
argued by the Examiner against claim 1.
CONTACT INFORMATION
THIS ACTION IS MADE FINAL. The Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
Any inquiry concerning this communication from the Examiner should be directed to Eric S. McCall whose telephone number is 571-272-2183. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/Eric S. McCall/Primary Examiner
Art Unit 2855
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