DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
2. This Office Action is sent in response to Applicant's Communication received on September 16, 2025.
Response to Arguments
Applicant’s arguments filed September 16, 2025, with respect to claims 3 and 11 rejections have been fully considered and are persuasive. Accordingly, said claims 3 and 11 rejections have been withdrawn.
Further on, claims 3 and 11 are objected as allowable subject matter.
Applicant's arguments filed September 16, 2025 regarding claims 1-2, 4-10 and 12 have been fully considered but they are not persuasive as explained below.
Applicant respectfully asserts, regarding claim 1, that the cited prior art fails to meet the limitations “…method for controlling the traction of a vehicle hydraulic assistance circuit, said hydraulic assistance circuit comprising a unidirectional variable displacement hydraulic pump, having its displacement controller servo-controlled by a pressure setpoint…” in at least claim 1.
More specifically, Applicant respectfully asserts that Didierjean (cited prior art) does not mention or suggest using such a type of hydraulic pump. Secondly, Didierjean relates to a displacement control for a hydraulic pump. Such a control is inadequate and totally irrelevant for a load sensing pump. Thirdly, Didierjean relates to an entirely different application, which is adapting the flow delivered by a hydraulic pump to a circuit to the specificities of this circuit. Didierjean therefore indicates that a correction value for the displacement of the hydraulic pump is determined and adapted to the actual condition of the system. Didierjean aims at minimizing this correction value, so as to minimize the reaction of the system to specific conditions such as a loss of adherence. It is pointed out that the target pressure for the hydraulic pump is not modified and remains a constant value.
The Examiner respectfully submits, regarding claim 1, that Didierjean discloses a unidirectional variable displacement hydraulic pump (Variable-displacement hydraulic pump 7: Fig. 1), having its displacement controller (Controller 9: Fig. 1) servo-controlled by a pressure setpoint. Where the theoretical displacement value corresponding to the desired flow rate is determined in order to drive the carrying wheels 51 and 52 to the desired rotational speed. Considering a vehicle traveling under predetermined and constant conditions, the thus determined displacement value is therefore constant. It is however understood that in operation under real conditions, the target pressure and displacement value will change as a function of time, as a function of the rotational speed of the wheels of the main axle 3 driven by the engine 1 (or a parameter related thereto) ([0035]).
Applicant respectfully asserts, regarding claim 9, that the cited prior art fails to meet the limitations in at least claim 9 for the same arguments as explained by Applicant with respect to claim 1 above.
The Examiner respectfully submits, regarding claim 9, the same explanations with respect to claim 1 above.
Disposition of Claims
Claims 1-12 are pending in this application.
Claims 3 and 11 are objected as allowable subject matter.
Claims 1-2, 4-10 and 12 are rejected.
Allowable Subject Matter
Claims 3 and 11 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims.
Claim Rejections - 35 USC § 102
The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action:
A person shall be entitled to a patent unless –
(a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale or otherwise available to the public before the effective filing date of the claimed invention.
(a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention.
Claims 1-2 and 4-8 are rejected under 35 U.S.C. 102(a)(1) as being anticipated by (Didierjean – US 2020/0232556 A1).
Regarding claim 1, Didierjean discloses:
A method for controlling the traction of a vehicle hydraulic assistance circuit (Vehicle provided with hydraulic assistance on an axle: Fig. 1), said hydraulic assistance circuit comprising:
a unidirectional variable displacement hydraulic pump (Variable-displacement hydraulic pump 7: Fig. 1), having its displacement controller (Controller 9: Fig. 1) servo-controlled by a pressure setpoint,
said method comprising the following steps:
a control step, wherein a target pressure is applied to the hydraulic assistance circuit, and a setpoint pressure and a theoretical value of a parameter (Theoretical displacement value corresponding to the desired flow rate: [0035-0042, 0061-0063, 0073-0074, 0081, 0088]) of the hydraulic assistance circuit are determined;
a setpoint step, wherein a pressure setpoint is applied to the hydraulic pump, equal to the setpoint pressure ([0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D: “The displacement of the hydraulic pump 7 is initially equal to C+Cc+Vc, with C being the theoretical displacement value, Cc the correction constant and Vc the correction variable as already described above, the adjustment of the displacement being performed within the limits of the predetermined correction variable Vc”);
a measurement step, wherein an actual value is measured in said hydraulic assistance circuit ([0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D: “At a moment Te, a command for evaluating the displacement of the hydraulic pump 7 is performed. As previously described, the correction constant is then adjusted as a function of the correction variable, in order to minimize the latter. Indeed, the correction constant integrates two components; a theoretical constant Ct and an adjusted constant Ca. The theoretical constant Ct remains unchanged, while the adjusted constant is changed, for example to correspond to 0.9 or 0.95 Vc during the execution of the evaluation command. The correction constant thus takes a new value Cc′, whereas the correction variable Vc is greatly reduced (it is then indicated by Vc′), and then has a value that can thus be equal to 10% or 5% of its value preceding the evaluation command. It is here understood that it is possible to execute several evaluation commands successively in order to refine the value of the adjusted constant Ca and therefore of the correction constant Cc, the operation then remaining unchanged”);
a comparison step, wherein the actual value measured in said hydraulic assistance circuit is compared to the theoretical value ([0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D: “In the example represented, the correction variable Vc is represented as having a positive value. However, it is understood that this correction variable Vc can have a positive or negative value, that is to say, represent a rolling radius too large or too small compared to what is originally provided in the value C. It is therefore possible that the adjustment of the pump displacement is positive or negative at start-up, to obtain the pressure Ptarget. Consequently, the correction that will follow will be positive or negative”);
if a gap between the actual value and the theoretical value is greater than a threshold value, a step of adjusting the setpoint is carried out in which the pressure setpoint of the hydraulic pump is modified so that it is equal to an actual pressure, to within an adjustment coefficient ([0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D: “When the output pressure of the hydraulic pump 7 reaches the threshold value at a moment T3, the hydraulic assistance becomes fully effective, and then exerts a torque on the second axle 5 ensuring a driving of the vehicle, so as to control the rotational speed of the wheels of the first axle 3 (graph 3B). Unlike the example represented in FIGS. 2A to 2D, it is seen here that the displacement of the hydraulic pump 7 is very close to the ideal displacement value for perfect synchronization of the vehicle axles (graph 3C), the value of Vc having been minimized. The hydraulic assistance is thus provided with an optimal displacement” and “At moment T4, the slip stops. The wheels of the first axle 3 recover their initial rotational speed (graph 3B), and the output pressure of the hydraulic pump 7 also returns to its initial value Ptarget (graph 3D). The displacement of the hydraulic pump 7 is changed to return to its value C+Cc′+Vc′”).
Regarding claim 2, Didierjean disclose the method according to claim 1, and further on Didierjean also discloses:
wherein following the setpoint adjustment step, a rebound step is carried out, wherein the pressure setpoint is progressively modified so as to return it to the target pressure (Didierjean [0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D).
Regarding claim 4, Didierjean disclose the method according to claim 1, and further on Didierjean also discloses:
wherein the theoretical value is a theoretical pressure, and the measurement step is carried out by means of a pressure sensor positioned in the hydraulic assistance circuit (Didierjean [0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D).
Regarding claim 5, Didierjean disclose the method according to claim 4, and further on Didierjean also discloses:
wherein the rebound step is carried out if the pressure setpoint is strictly less than the target pressure (Didierjean [0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D).
Regarding claim 6, Didierjean disclose the method according to claim 1, and further on Didierjean also discloses:
wherein the measurement step and the comparison step are carried out by determining, by means of a computer and by comparing: a theoretical flow rate in the hydraulic assistance circuit as a function in particular of theoretical operating parameters of the hydraulic assistance circuit, and an actual flow rate, as a function of the parameters measured in the hydraulic assistance circuit (Didierjean [0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D).
Regarding claim 7, Didierjean disclose the method according to claim 6, and further on Didierjean also discloses:
wherein the actual flow rate is determined by means of a position sensor of a plate of the hydraulic pump of the hydraulic assistance circuit (Didierjean [0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D).
Regarding claim 8, Didierjean disclose the method according to claim 1, and further on Didierjean also discloses:
wherein, during the measurement step and the comparison step, two actual values are measured for two distinct parameters, and the actual value measured in said hydraulic assistance circuit for each of these two parameters is compared to an associated theoretical value for each of these parameters; and wherein the setpoint adjustment step is carried out if a gap between the actual value and the theoretical value of at least one of said two parameters is greater than a threshold value (Didierjean [0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D).
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries set forth in Graham v. John Deere Co., 383 U.S. 1, 148 USPQ 459 (1966), that are applied for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or non-obviousness.
Claims 9-10 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over (Didierjean – US 2020/0232556 A1), in view of (Beck – US 4,236,595 A).
Regarding claim 9, Didierjean discloses:
A system for controlling the traction of an axle driven in rotation by a hydraulic assistance circuit (Vehicle provided with hydraulic assistance on an axle: Fig. 1), wherein said hydraulic assistance circuit comprises:
a unidirectional variable displacement hydraulic pump (Variable-displacement hydraulic pump 7: Fig. 1) having its displacement controller (Controller 9: Fig. 1) servo-controlled by a pressure setpoint, a hydraulic motor suitable for driving a movement member in rotation, the hydraulic pump being connected to the hydraulic motor (hydraulic motor 8: Fig. 1) via a closed-loop hydraulic circuit,
said traction control system comprising:
a control member, suitable for applying a setpoint to the hydraulic assistance circuit ([0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D);
a computer, suitable for determining a target control pressure as a function of the setpoint applied by the control member, a pressure setpoint applied to the hydraulic pump and a theoretical value of a parameter of the hydraulic assistance circuit (Theoretical displacement value corresponding to the desired flow rate: [0035-0042, 0061-0063, 0073-0074, 0081, 0088]);
a sensor, suitable for measuring an actual value of said parameter of the hydraulic assistance circuit ([0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D: “At a moment Te, a command for evaluating the displacement of the hydraulic pump 7 is performed. As previously described, the correction constant is then adjusted as a function of the correction variable, in order to minimize the latter. Indeed, the correction constant integrates two components; a theoretical constant Ct and an adjusted constant Ca. The theoretical constant Ct remains unchanged, while the adjusted constant is changed, for example to correspond to 0.9 or 0.95 Vc during the execution of the evaluation command. The correction constant thus takes a new value Cc′, whereas the correction variable Vc is greatly reduced (it is then indicated by Vc′), and then has a value that can thus be equal to 10% or 5% of its value preceding the evaluation command. It is here understood that it is possible to execute several evaluation commands successively in order to refine the value of the adjusted constant Ca and therefore of the correction constant Cc, the operation then remaining unchanged”),
wherein said computer is suitable for comparing the actual value to the theoretical value ([0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D: “In the example represented, the correction variable Vc is represented as having a positive value. However, it is understood that this correction variable Vc can have a positive or negative value, that is to say, represent a rolling radius too large or too small compared to what is originally provided in the value C. It is therefore possible that the adjustment of the pump displacement is positive or negative at start-up, to obtain the pressure Ptarget. Consequently, the correction that will follow will be positive or negative”), and,
if a gap between the actual value and the theoretical value is greater than a threshold value, to modify the control setpoint so that it is equal to the actual value, to within an adjustment coefficient ([0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D: “When the output pressure of the hydraulic pump 7 reaches the threshold value at a moment T3, the hydraulic assistance becomes fully effective, and then exerts a torque on the second axle 5 ensuring a driving of the vehicle, so as to control the rotational speed of the wheels of the first axle 3 (graph 3B). Unlike the example represented in FIGS. 2A to 2D, it is seen here that the displacement of the hydraulic pump 7 is very close to the ideal displacement value for perfect synchronization of the vehicle axles (graph 3C), the value of Vc having been minimized. The hydraulic assistance is thus provided with an optimal displacement” and “At moment T4, the slip stops. The wheels of the first axle 3 recover their initial rotational speed (graph 3B), and the output pressure of the hydraulic pump 7 also returns to its initial value Ptarget (graph 3D). The displacement of the hydraulic pump 7 is changed to return to its value C+Cc′+Vc′”).
But Didierjean does not explicitly and/or specifically meet the following limitations:
(A) {{{an open-loop hydraulic circuit}}}.
However, regarding limitation (A) above, Beck discloses/teaches the following:
With reference to FIG. 1 of the drawing, the auxiliary hydraulic drive system of the present invention is generally described by reference numeral 10. The auxiliary system 10 is supplied with hydraulic energy by a pressure compensated variable displacement pump 12, which is of the axial piston type well known in the prior art. Pump 12 is driven by the power source of the tractor 14 which also drives the main drive wheels 18 through a conventional mechanical transmission 16. Pump 12 supplies two fixed displacement reversible wheel motors 20 and 22 through a selector valve 24 in a parallel circuit which branches from a divider valve 26 into individual motor lines 30 and 32 to their respective motors. Motors 20 and 22 drive wheels 19 which are the steerable front wheels of the tractor. Sensor 21 on wheel motor 20 electrically senses the wheel speed of the front wheels while sensor 23 on wheel 18 senses the main drive wheel speed. Motor return lines 34 and 36 are joined in a second divider valve 28 for return to reservoir 40 via line 38. Divider valves 26 and 28 are not shown in detail, but are of the type described in U.S. Pat. No. 4,140,196. Divider valves 26 and 28 equally divide the flow from a single source to the individual motors, regardless of the flow rate, allowing a pre-arranged flow differential between the motors for cornering (Column 2, Lines 34-59).
To engage the auxiliary system 10 for movement in a forward direction, selector valve 24 is shifted to its position 65, which connects pump discharge flow in line 11 directly to inlet line 41, while draining return line 38 to reservoir 40. In a no-slip condition, variable displacement pump 12 will stand by at a set pressure level of 1500 PSI, for example, which is determined by the compressive force of spring 51 in servo cylinder 48 (see FIG. 2). As the main drive wheels 18 of the tractor increase in speed, the front wheels 19 will also increase in speed requiring a higher flow rate from pump 12. This drops the working pressure in the auxiliary system 10 causing the servo cylinder 48 to maintain its pressure compensating level by increasing the stroke on the pump 12 until that pressure level is regained (Column 3, Lines 45-59).
Fig. 1 shows an open-loop hydraulic circuit between the variable displacement pump (12) and the low-pressure charging pump (42) that includes reservoir (40) and relief valve (46).
Accordingly, one skilled in the art would have been motivated to incorporate the teachings of Beck into Didierjean to provide constant low-pressure fluid to the spring tension cylinder, and also charging the auxiliary system in its freewheeling neutral position while maintaining the operating pressure and avoiding excessive pressure via the relief valve.
Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have modified the hydraulic pump system of Didierjean incorporating the use of an open-loop hydraulic circuit as taught by Beck to provide constant low-pressure fluid to the spring tension cylinder, and also charging the auxiliary system in its freewheeling neutral position while maintaining the operating pressure and avoiding excessive pressure via the relief valve.
Regarding claim 10, Didierjean as combined above disclose the system according to claim 9, and further on Didierjean as combined above also discloses:
wherein the sensor comprises a pressure sensor in the hydraulic circuit (Didierjean [0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D).
Regarding claim 12, Didierjean as combined above disclose the system according to claim 10, and further on Didierjean as combined above also discloses:
wherein the sensor comprises two pressure sensors suitable for measuring the pressure at the terminals of a calibrated restriction of the hydraulic assistance circuit, and the computer is suitable for determining a theoretical flow rate in the hydraulic circuit, and an actual flow rate delivered by the hydraulic pump as a function of the pressure measurements carried out by said pressure sensors (Didierjean [0035, 0046, 0054, 0061-0075, 0079, 0081-0083] and Figs. 3A-3D).
Conclusion
THIS ACTION IS MADE FINAL. 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 or earlier communications from the examiner should be directed to Ruben Picon-Feliciano whose telephone number is (571)-272-4938. The examiner can normally be reached on Monday-Thursday within 11:30 am-7:30 pm ET.
If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Lindsay M. Low can be reached on (571)272-1196. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/RUBEN PICON-FELICIANO/Examiner, Art Unit 3747
/GRANT MOUBRY/Primary Examiner, Art Unit 3747