BRAKE ACTUATORS AND SYSTEMS FOR MONITORING STROKE OF BRAKE ACTUATORS
NON-FINAL OFFICE ACTION
This action is in response to the Applicant’s Request for Continued Examination along with amendment of March 03, 2026.
SPECIFICATION
The lengthy specification has not been checked to the extent necessary to determine the presence of all possible minor errors. The Applicant's cooperation is requested in correcting any errors of which the Applicant may become aware of in the specification.
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. § 103
In accordance with 35 U.S.C. 103, 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 of this title, 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.
Claims 1, 2, 7, 8, 11, 12, 14, 17, 18, 21, 22, 24, 25, and 27 are rejected under 35 U.S.C. 103 as being unpatentable over Weant et al. (6,501,375).
With respect to amended independent claim 1, Weant et al. set forth a system for monitoring stroke of a spring brake actuator of a vehicle, the system comprising:
a spring brake actuator having a push rod, wherein pneumatic activation of the spring brake actuator causes the push rod to further extend out of the spring brake actuator to thereby activate braking of the vehicle, and wherein pneumatic deactivation of the spring brake actuator causes the push rod to retract back into the spring brake actuator to thereby deactivate braking of the vehicle (col. 1, lines 11+);
a first magnet (124) and a second magnet (128) coupled to the push rod (122), the second magnet spaced apart from the first magnet (Fig. 8);
a sensor configured to sense a value of a combined magnetic field created by the first magnet and the second magnet (col. 4, lines 23 - 27 and col. 5, lines 59+); and
a control system configured to determine stroke of the push rod based on the combined magnetic field (col. 9, lines 10 - 14).
Weant et al. fail to explicitly set forth that the sensor senses a magnetic field strength which is created by the first and second magnets. Thus, Weant et al. fail to explicitly set forth that the sensor senses a value of the combined magnetic field strength created by the first and second magnets.
However, it would have been obvious to one having ordinary skill in the art armed with the Weant et al. teaching that the sensor does sense a magnetic field strength, and thus a value of the combined magnetic field strength, created by the first magnet and by the second magnet.
The motivation being that magnets create a magnetic field and a magnetic field inherently has a value of magnetic strength. Thus, when the sensor senses the magnets in Weant et al., it is sensing the value of magnetic field created by both the first and second magnets because both magnetic fields remain present even though one magnetic field may be of insignificant strength compare to the other magnetic field. In addition, when the magnetic fields are sensed, a value of the magnetic strength is inherently being detected since the magnetic field varies in strength depending on the position of the sensor.
With respect to claim 2, Weant et al. set forth that the first magnet is fixed relative to the second magnet such that as the push rod moves, the distance between the first magnet (124) and the second magnet (128) remains constant (Fig. 8).
With respect to claim 7, Weant et al. set forth a sleeve (122) that couples the second magnet (128) to the push rod (50).
With respect to claim 8, Weant et al. set forth that the sleeve comprises a ferromagnetic material (col. 5, lines 59 +).
With respect to independent claim 11, Weant et al. set forth a spring brake actuator for braking a wheel of a vehicle, the spring brake actuator comprising:
a chamber (top chamber 42 or bottom chamber of brake actuator 26);
a push rod (50) extending from the chamber (Fig. 2), wherein pneumatic activation of the spring brake actuator causes the push rod to further extend out of the chamber to thereby activate braking of the wheel of the vehicle, and wherein pneumatic deactivation of the spring brake actuator causes the push rod to retract back into the chamber to thereby deactivate braking of the wheel of the vehicle (col. 1, lines 11+);
a first magnet (124) coupled to the push rod (122);
a second magnet (128) coupled to the push rod (122), the second magnet being spaced apart from the first magnet (Fig. 8);
a sensor configured to sense a magnetic field created by the first magnet and the second magnet (col. 4, lines 23 - 27 and col. 5, lines 59+); and
a control system configured to determine stroke of the push rod based on the magnetic field (col. 9, lines 10 - 14).
However, Weant et al. fail to explicitly set forth that the sensor senses a value of a combined magnetic field strength which is created by the first and second magnets.
Nonetheless, it would have been obvious to one having ordinary skill in the art armed
with the Weant et al. teaching that the sensor does sense a value of a combined magnetic field strength created by the first magnet and by the second magnet.
The motivation being that magnets create a magnetic field and a magnetic field inherently has a value of magnetic strength. Thus, when the sensor senses the magnets in Weant et al., it is sensing the value of magnetic field created by both the first and second magnets because both magnetic fields remain present even though one magnetic field may be of insignificant strength compare to the other magnetic field. In addition, when the magnetic fields are sensed, a value of the magnetic strength is inherently being detected since the magnetic field varies in strength depending on the position of the sensor.
With respect to claim 12, Weant et al. set forth that the first magnet is fixed relative to the second magnet such that as the push rod moves, the distance between the first magnet (124) and the second magnet (128) remains constant (Fig. 8).
With respect to claim 14, Weant et al. set forth that the second magnet (128) is coupled to a rod end of the push rod (Fig. 8).
With respect to claim 17, Weant et al. set forth a sleeve (122) that couples the second magnet (128) to the push rod (50).
With respect to claim 18, Weant et al. set forth that the sleeve comprises a ferromagnetic material (col. 5, lines 59 +).
With respect to independent claim 21, Weant et al. set forth a method for monitoring stroke of a spring brake actuator (26), the method comprising:
coupling a first magnet (124) and a second magnet (128) to a push rod (122) of the spring brake actuator (Fig. 8);
actuating the spring brake actuator to thereby move the push rod (Fig. 2);
sensing a magnetic field created by the first magnet and the second magnet as the push rod is moved (col. 4, lines 23 - 27 and col. 5, lines 59+); and
determining stroke of the push rod (col. 9, lines 10 - 14).
However, Weant et al. fail to explicitly set forth determining of the stroke of the push rod based on a value of a combined magnetic field strength created by the first and second magnets.
Nonetheless, it would have been obvious to one having ordinary skill in the art armed with the Weant et al. teaching to determine the stroke of the push rod based on a value of a combined magnetic field strength created by the first magnet and by the second magnet.
The motivation being that magnets create a magnetic field and a magnetic field inherently has a value of magnetic strength. Thus, when the sensor senses the magnets in Weant et al., it is sensing a value of the combined magnetic field created by the first or second magnets because both magnetic fields remain present even though one magnetic field may be of insignificant strength compare to the other magnetic field. In addition, when the magnetic fields are sensed, a value of the magnetic strength is inherently being detected since the magnetic field varies in strength depending on the position of the sensor.
With respect to claim 22, Weant et al. set forth that the first magnet is fixed relative to the second magnet such that as the push rod moves, the distance between the first magnet (124) and the second magnet (128) remains constant (Fig. 8).
With respect to claim 24, Weant et al. set forth that the second magnet (128) is coupled to the push rod (122) by way of a sleeve (122).
With respect to claim 25, Weant et al. set forth that the sleeve comprises a ferromagnetic material (col. 5, lines 59 +).
With respect to claim 27, Weant et al. set forth that the magnetic field strength, and thus a value thereof, is indicative of the position of the push rod (122) after extension of the push rod.
Allowable Subject Matter
Claims 3, 5, 6, 9, 10, 13, 15, 16, 19, 20, and 23 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 for the reasons as was set forth in the said previous Office Action.
Independent claim 26 is allowable over the prior art because the prior art fails to teach or suggest that the brake actuator has a chamber from which the push rod extends with the first magnet positioned in the chamber and the second magnet positioned exterior of the chamber.
Response To Arguments
The Applicant’s arguments have been considered but have not been found to be persuasive. While the applied prior art of Weant et al. does not explicitly teach the detection of a specific value of a combined magnetic field strength, Weant et al. do teach the presence of magnets (124, 126, and 128) and thus the corresponding magnetic fields. With the presence of magnetic fields comes an inherent value of magnetic field strength for any specific position of the sensor. Thus, the sensors (60, 62), when activated, will sense the inherent strength value of a resultant of any and all magnetic fields present even though one magnetic field may be of insignificant strength compare to another magnetic field.
CONTACT INFORMATION
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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