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 October 23, 2025.
Information Disclosure Statement
The information disclosure statement (IDS) submitted on November 12, 2025 was submitted in compliance with the provisions of 37 CFR 1.97. Accordingly, the information disclosure statement is being considered by the examiner.
Response to Arguments
Applicant’s amendments filed October 23, 2025, with respect to claims 1-20 rejections under 35 U.S.C. 112(b) have been fully considered and are persuasive. Accordingly, said claims 1-20 rejections under 35 U.S.C. 112(b) have been withdrawn.
Applicant’s arguments/remarks filed October 23, 2025, with respect to claims 3, 5, 7, 14-15 and 17 rejections under 35 U.S.C. 103 as being unpatentable over (Ogihara – US 2020/0125108 A1), in view of (MATSUSHITA – JP H11291931 A) have been fully considered and are persuasive. Accordingly, said claims 3, 5, 7, 14-15 and 17 rejections under 35 U.S.C. 103 as being unpatentable over (Ogihara – US 2020/0125108 A1), in view of (MATSUSHITA – JP H11291931 A) have been withdrawn.
Further on, claims 3, 5, 7, 14-15 and 17 are objected as allowable subject matter.
Applicant’s amendments/arguments filed October 23, 2025, with respect to the claims 1-2, 4, 6, 8-13, 16 and 18-20 rejections under 35 U.S.C. 103 as being unpatentable over (Ogihara – US 2020/0125108 A1), in view of (MATSUSHITA – JP H11291931 A) have been fully considered and are persuasive. Therefore, the rejections have been withdrawn. However, upon further consideration, a new ground(s) of rejection is made in view of Suzuki as explained below.
Disposition of Claims
Claims 1-20 are pending in this application.
Claims 3, 5, 7, 14-15 and 17 are objected as allowable subject matter.
Claims 1-2, 4, 6, 8-13, 16 and 18-20 are rejected.
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 1-2, 4, 6, 8-13, 16 and 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over (Ogihara – US 2020/0125108 A1), in view of (MATSUSHITA – JP H11291931 A), further in view of (Suzuki – JP 6649852 B2).
Regarding claim 1, Ogihara discloses:
A control system for a work vehicle (dump truck vehicle 2: Fig. 1) comprising:
a first operation command unit (travel control unit 37: Figs. 1-3 and [0025-0048, 0061]: “The travel control unit 37 outputs to the travel device 21 an operation command for controlling the travel device 21 including the steering device 26 based on the limiting travel speed Vsmax, which is a changed travel parameter. The operation command is a command for controlling a travel state of the travel device 21 and is determined based on the travel course data and the travel parameter. The travel state of the travel device 21 includes driving, braking, and swinging of the travel device 21. The travel control unit 37 outputs to the travel device 21 an operation command for causing the travel device 21 to drive, brake, and swing based on the travel course data and the limiting travel speed Vsmax, which is a travel parameter”) that outputs a first operation command (operation command is a command for controlling a travel state of the travel device 21 and is determined based on the travel course data and the travel parameter) to operate a steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]) of the work vehicle (dump truck vehicle 2: Fig. 1) in a first steering direction (a travel direction thru steering device 26: [0028]), in a stopped state (“stationary steering operation” state and/or “before start of traveling” state: [0124, 0114-0115, 0123-0126]) of the work vehicle (dump truck vehicle 2: Fig. 1);
a state monitoring unit (steering angle sensor 18 and travel course data acquisition unit 32 and temperature data acquisition unit 33: Figs. 1-3 and [0054-0055, 0086-0089, 0102]) that monitors a state of the steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]);
a restriction determination unit (maximum steering speed calculation unit 35: Figs. 1-3 and [0054-0055, 0086-0089, 0102]) that determines whether to restrict operation of the steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]) in the first steering speed, based on the state during output of the first operation command; and
a restriction command unit (command output unit 36: Figs. 1-3 and [0054-0055, 0086-0089, 0102]) that restricts the operation of the steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]) in the first steering speed, based on the determination by the restriction determination unit (maximum steering speed calculation unit 35: Figs. 1-3 and [0054-0055, 0086-0089, 0102]).
But Ogihara does not explicitly meet the following limitations:
(A) restricting the steering direction of the steering device.
It is noted that while Ogihara discloses the uses of the steering angle (i.e., claimed “steering direction”) to calculate the maximum allowable steering speed Vϴmax, it is not explicitly recited in Ogihara the limitation “…restricts the operation of the steering device in the first steering direction, based on the determination by the restriction determination unit…” as claimed above.
However, regarding limitation (A) above, MATSUSHITA discloses/teaches the following:
The steering direction determining means 42 determines the steering direction, that is, the direction in which the steering driving means 39 is driven, based on the turning angle. This is because when the turning angle is more than ± 90 degrees with respect to the forward direction of the vehicle, the direction of the driver's cab 4 is reversed, so that the actual steering direction is reversed with respect to the steering direction operated by the operator. This is to prevent an erroneous operation due to the reversal in response to the feeling of performing the operation. Therefore, in this case, when the steering operation is performed in a state where the vehicle turns in the reverse direction at a predetermined allowable angle (for example, 10 degrees, including 0 degrees) more than ± 90 degrees with respect to the forward direction of the vehicle. The steering driving direction is opposite to the steering direction in the forward direction. This determination result is output to the traveling command calculation means 46 and the reverse steering correction means 47 ([0032-0051]). The reverse steering correction means 47 outputs the steering angle command from the steering angle command means 41 to the steering drive means 39. At this time, the driving direction of the steering driving unit 39 is switched so that the steering is performed in accordance with the steering driving direction determined by the steering direction determining unit 42 and the steering drive means 39 ([0032-0051]).
FIG. 4 is a block diagram showing a control function according to the present invention, and the configuration of each control function will be described below with reference to FIG. The steering amount detection means 51 detects an operation amount of the steering operation means 9, and uses the detected steering operation amount (hereinafter, simply referred to as a steering amount) to the steering angle command means 41 of the control unit 40 and the rotation amount. It outputs to the number ratio calculating means 45. The steering angle command means 41 outputs a steering angle command for driving the steering drive means 39 based on the steering amount. That is, the steering angle command is set to reverse steering so that the steering angle α (the rotation angle around the articulate pin 36 with respect to the rear frame 31 with respect to the front frame 35) is cut off in accordance with the magnitude of the steering amount. It is output to the correction means 47 ([0032-0067]).
In the state, the steering operation direction and the actual steering direction due to the steering operation direction are made opposite to each other, so that it is adapted to human operation feeling and operability is improved. Therefore, erroneous operations such as reverse steering during turning can be prevented ([0028]).
The steering can be performed very easily and smoothly, particularly at the time of "stationary steering" in which the steering is largely performed at a low speed. Therefore, in the crawler type construction machine having the articulated steering mechanism, the operability and the steerability when the direction is changed on the spot are improved.
Further on, regarding limitation (A) above, Suzuki discloses/teaches the following:
When the detected steering angle θs is larger than the second detected steering angle θs2, the control unit 11 maintains the torque when the detected steering angle θs is the second detected steering angle θs2 (hereinafter, referred to as minimum torque). In the present embodiment, the rate of change of the first limit amount is constant irrespective of the detected steering angle θs, the minimum torque is constant irrespective of when the vehicle is moving forward or backward, and irrespective of whether the vehicle is turning right or left. The rate of change and the minimum torque are constant ([0032]).
The third control mode is a control mode in which when the detected vehicle speed V is higher than the first predetermined speed V1, the vehicle speed is equal to or lower than the limit vehicle speed Vlmt shown in FIG. The limit vehicle speed Vlmt is a vehicle speed value set in advance in relation to the detected steering angle θs, and is a vehicle speed value that decreases as the detected steering angle θs increases ([0033]).
Details of Control FIG. 5 shows an example of a control flow of the above “Overview of Control”. A program for executing the control flow is stored in a nonvolatile storage unit such as a ROM. The relationship between the detected steering angle θs, the first limit torque (first limit amount), and the vehicle speed limit Vlmt (second limit torque) is stored in a nonvolatile storage unit 15 (see FIG. 2) such as a ROM in advance ([0042]).
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 steering control system of Ogihara incorporating additional controller communications/calculation-unit modules/instructions as taught by MATSUSHITA and Suzuki to improve operability, while erroneous operations such as reverse steering during turning can be prevented.
Regarding claim 11, Ogihara discloses:
A control method for a work vehicle (dump truck vehicle 2: Fig. 1) comprising:
outputting a first operation command to operate (travel control unit 37: Figs. 1-3 and [0025-0048, 0061]: “The travel control unit 37 outputs to the travel device 21 an operation command for controlling the travel device 21 including the steering device 26 based on the limiting travel speed Vsmax, which is a changed travel parameter. The operation command is a command for controlling a travel state of the travel device 21 and is determined based on the travel course data and the travel parameter. The travel state of the travel device 21 includes driving, braking, and swinging of the travel device 21. The travel control unit 37 outputs to the travel device 21 an operation command for causing the travel device 21 to drive, brake, and swing based on the travel course data and the limiting travel speed Vsmax, which is a travel parameter”) a steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]) of the work vehicle (dump truck vehicle 2: Fig. 1) in a first steering direction, in a stopped state (“stationary steering operation” state and/or “before start of traveling” state: [0124, 0114-0115, 0123-0126]) of the work vehicle (dump truck vehicle 2: Fig. 1);
monitoring a state (steering angle sensor 18 and travel course data acquisition unit 32 and temperature data acquisition unit 33: Figs. 1-3 and [0054-0055, 0086-0089, 0102]) of the steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]);
determining whether to restrict operation (maximum steering speed calculation unit 35: Figs. 1-3 and [0054-0055, 0086-0089, 0102]) of the steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]) in the first steering speed, based on the state during output of the first operation command; and
restricting the operation (command output unit 36: Figs. 1-3 and [0054-0055, 0086-0089, 0102]) of the steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]) in the first steering speed, based on the determination about whether to restrict the operation of the steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]).
But Ogihara does not explicitly meet the following limitations:
(A) restricting the steering angle (i.e., claimed “steering direction”) of the steering device.
It is noted that while Ogihara discloses the uses of the steering angle (i.e., claimed “steering direction”) to calculate the maximum allowable steering speed Vϴmax, it is not explicitly recited in Ogihara the limitation “…restricts the operation of the steering device in the first steering direction, based on the determination by the restriction determination unit…” as claimed above.
However, regarding limitation (A) above, MATSUSHITA discloses/teaches the following:
The steering direction determining means 42 determines the steering direction, that is, the direction in which the steering driving means 39 is driven, based on the turning angle. This is because when the turning angle is more than ± 90 degrees with respect to the forward direction of the vehicle, the direction of the driver's cab 4 is reversed, so that the actual steering direction is reversed with respect to the steering direction operated by the operator. This is to prevent an erroneous operation due to the reversal in response to the feeling of performing the operation. Therefore, in this case, when the steering operation is performed in a state where the vehicle turns in the reverse direction at a predetermined allowable angle (for example, 10 degrees, including 0 degrees) more than ± 90 degrees with respect to the forward direction of the vehicle. The steering driving direction is opposite to the steering direction in the forward direction. This determination result is output to the traveling command calculation means 46 and the reverse steering correction means 47 ([0032-0051]). The reverse steering correction means 47 outputs the steering angle command from the steering angle command means 41 to the steering drive means 39. At this time, the driving direction of the steering driving unit 39 is switched so that the steering is performed in accordance with the steering driving direction determined by the steering direction determining unit 42 and the steering drive means 39 ([0032-0051]).
FIG. 4 is a block diagram showing a control function according to the present invention, and the configuration of each control function will be described below with reference to FIG. The steering amount detection means 51 detects an operation amount of the steering operation means 9, and uses the detected steering operation amount (hereinafter, simply referred to as a steering amount) to the steering angle command means 41 of the control unit 40 and the rotation amount. It outputs to the number ratio calculating means 45. The steering angle command means 41 outputs a steering angle command for driving the steering drive means 39 based on the steering amount. That is, the steering angle command is set to reverse steering so that the steering angle α (the rotation angle around the articulate pin 36 with respect to the rear frame 31 with respect to the front frame 35) is cut off in accordance with the magnitude of the steering amount. It is output to the correction means 47 ([0032-0067]).
In the state, the steering operation direction and the actual steering direction due to the steering operation direction are made opposite to each other, so that it is adapted to human operation feeling and operability is improved. Therefore, erroneous operations such as reverse steering during turning can be prevented ([0028]).
The steering can be performed very easily and smoothly, particularly at the time of "stationary steering" in which the steering is largely performed at a low speed. Therefore, in the crawler type construction machine having the articulated steering mechanism, the operability and the steerability when the direction is changed on the spot are improved.
Further on, regarding limitation (A) above, Suzuki discloses/teaches the following:
When the detected steering angle θs is larger than the second detected steering angle θs2, the control unit 11 maintains the torque when the detected steering angle θs is the second detected steering angle θs2 (hereinafter, referred to as minimum torque). In the present embodiment, the rate of change of the first limit amount is constant irrespective of the detected steering angle θs, the minimum torque is constant irrespective of when the vehicle is moving forward or backward, and irrespective of whether the vehicle is turning right or left. The rate of change and the minimum torque are constant ([0032]).
The third control mode is a control mode in which when the detected vehicle speed V is higher than the first predetermined speed V1, the vehicle speed is equal to or lower than the limit vehicle speed Vlmt shown in FIG. The limit vehicle speed Vlmt is a vehicle speed value set in advance in relation to the detected steering angle θs, and is a vehicle speed value that decreases as the detected steering angle θs increases ([0033]).
Details of Control FIG. 5 shows an example of a control flow of the above “Overview of Control”. A program for executing the control flow is stored in a nonvolatile storage unit such as a ROM. The relationship between the detected steering angle θs, the first limit torque (first limit amount), and the vehicle speed limit Vlmt (second limit torque) is stored in a nonvolatile storage unit 15 (see FIG. 2) such as a ROM in advance ([0042]).
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 steering control system of Ogihara incorporating additional controller communications/calculation-unit modules/instructions as taught by MATSUSHITA and Suzuki to improve operability, while erroneous operations such as reverse steering during turning can be prevented.
Regarding claim 2, Ogihara as combined above disclose the control system for a work vehicle according to claim 1, and further on Ogihara as combined above also discloses:
wherein the state includes an operation speed (the travel parameter includes the steering speed Vθ of the steering device 26: Ogihara [0131]) of the steering device (steering device 26: Figs. 1-3 and [0025-0048, 0061]).
Regarding claim 4, Ogihara as combined above disclose the control system for a work vehicle according to claim 1, and further on Ogihara as combined above also discloses:
wherein the first operation command unit (travel control unit 37: Figs. 1-3 and [0025-0048, 0061]: “The travel control unit 37 outputs to the travel device 21 an operation command for controlling the travel device 21 including the steering device 26 based on the limiting travel speed Vsmax, which is a changed travel parameter. The operation command is a command for controlling a travel state of the travel device 21 and is determined based on the travel course data and the travel parameter. The travel state of the travel device 21 includes driving, braking, and swinging of the travel device 21. The travel control unit 37 outputs to the travel device 21 an operation command for causing the travel device 21 to drive, brake, and swing based on the travel course data and the limiting travel speed Vsmax, which is a travel parameter”) outputs the first operation command such that the steering device (26) operates in a target state, and the restriction determination unit determines whether to restrict the operation of the steering device in the first steering direction, based on a difference between the target state and the state (As combined above Ogihara with MATSUSHITA).
Regarding claim 6, Ogihara as combined above disclose the control system for a work vehicle according to claim 1, and further on Ogihara as combined above also discloses:
wherein the first operation command unit (travel control unit 37: Figs. 1-3 and [0025-0048, 0061]: “The travel control unit 37 outputs to the travel device 21 an operation command for controlling the travel device 21 including the steering device 26 based on the limiting travel speed Vsmax, which is a changed travel parameter. The operation command is a command for controlling a travel state of the travel device 21 and is determined based on the travel course data and the travel parameter. The travel state of the travel device 21 includes driving, braking, and swinging of the travel device 21. The travel control unit 37 outputs to the travel device 21 an operation command for causing the travel device 21 to drive, brake, and swing based on the travel course data and the limiting travel speed Vsmax, which is a travel parameter”) outputs the first operation command such that the steering device operates in the first steering direction to a first target angle, and the restriction command unit changes the first target angle to restrict the operation of the steering device in the first steering direction (As combined above Ogihara with MATSUSHITA).
Regarding claim 8, Ogihara as combined above disclose the control system for a work vehicle according to claim 1, and further on Ogihara as combined above also discloses:
wherein the restriction command unit (command output unit 36: Figs. 1-3 and [0054-0055, 0086-0089, 0102]) stops output of the first operation command to restrict operation of the steering device (26) in the first steering direction (As combined above Ogihara with MATSUSHITA).
Regarding claim 9, Ogihara as combined above disclose the control system for a work vehicle according to claim 1, and further on Ogihara as combined above also discloses:
wherein the steering device (26) includes a link mechanism (rod 133: Fig. 2) that is connected to a wheel (front wheel 27F: Fig. 2) of the work vehicle (dump truck vehicle 2: Fig. 1), and a hydraulic cylinder (steering cylinder 13: Fig. 2) that drives the link mechanism (rod 133: Fig. 2) based on hydraulic oil (hydraulic oil supplied to the steering cylinder 13: [0056]), and the control system further comprising: a hydraulic oil temperature monitoring unit (temperature data acquisition unit 33 and temperature sensor 17: Fig. 3) that monitors a temperature of the hydraulic oil (hydraulic oil supplied to the steering cylinder 13: [0056]); a warm-up determination unit that determines whether to perform a warm-up process for the steering device based on the temperature of the hydraulic oil; and a warm-up command unit that causes the first operation command unit to output the first operation command, based on the determination by the warm-up determination unit (Ogihara [0114]: “In the present embodiment, described is an example in which, {{{by raising the temperature T of the hydraulic oil before start of traveling}}} of the unmanned vehicle 2, the {{{steering responsiveness is improved}}}, and in which the unmanned vehicle 2 travels along the travel course”).
Regarding claim 10, Ogihara as combined above disclose the control system for a work vehicle according to claim 1, and further on Ogihara as combined above also discloses:
a second operation command unit (valve control unit 38 controls the valve device 12 so that the steering cylinder 13 may be actuated before start of traveling of the unmanned vehicle 2: Fig. 2 and [0123]) that outputs a second operation command to operate the steering device in a second steering direction opposite to the first steering direction, in a stopped state of the work vehicle after operation of the steering device in the first steering direction is restricted (As combined above Ogihara with MATSUSHITA).
Regarding claim 12, Ogihara as combined above disclose the control method for a work vehicle according to claim 11, and further on Ogihara as combined above also discloses:
outputting the first operation command such that the steering device operates in a target state; and determining whether to restrict the operation of the steering device in the first steering direction, based on a difference between the state and the target state (As combined above Ogihara with MATSUSHITA).
Please see same analysis for the equivalent limitations of the control system of claims above.
Regarding claim 13, Ogihara as combined above disclose the control method for a work vehicle according to claim 11, and further on Ogihara as combined above also discloses:
wherein the state includes an operation speed of the steering device (As combined above Ogihara with MATSUSHITA).
Please see same analysis for the equivalent limitations of the control system of claims above.
Regarding claim 16, Ogihara as combined above disclose the control method for a work vehicle according to claim 11, and further on Ogihara as combined above also discloses:
outputting the first operation command such that the steering device operates in the first steering direction to a first target angle; and changing the first target angle to restrict the operation of the steering device in the first steering direction (As combined above Ogihara with MATSUSHITA).
Please see same analysis for the equivalent limitations of the control system of claims above.
Regarding claim 18, Ogihara as combined above disclose the control method for a work vehicle according to claim 11, and further on Ogihara as combined above also discloses:
stopping output of the first operation command to restrict operation of the steering device in the first steering direction (As combined above Ogihara with MATSUSHITA).
Please see same analysis for the equivalent limitations of the control system of claims above.
Regarding claim 19, Ogihara as combined above disclose the control method for a work vehicle according to claim 11, and further on Ogihara as combined above also discloses:
wherein the steering device includes a link mechanism that is connected to a wheel of the work vehicle, and a hydraulic cylinder that drives the link mechanism based on hydraulic oil, and the control method further comprising: monitoring a temperature of the hydraulic oil; determining whether to warm up the steering device based on the temperature of the hydraulic oil; and outputting the first operation command based on the determination about whether to warm up the steering device (As combined above Ogihara with MATSUSHITA).
Please see same analysis for the equivalent limitations of the control system of claims above.
Regarding claim 20, Ogihara as combined above disclose the control method for a work vehicle according to claim 11, and further on Ogihara as combined above also discloses:
outputting a second operation command to operate the steering device in a second steering direction opposite to the first steering direction, in a stopped state of the work vehicle after operation of the steering device in the first steering direction is restricted (As combined above Ogihara with MATSUSHITA).
Please see same analysis for the equivalent limitations of the control system of claims above.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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