US 11,655,774 B2
Injector failure diagnostic device and injector failure diagnostic method
Tien Trien Le, Kanagawa (JP); Hisashi Yokoyama, Ibaraki (JP); Takahiro Sagara, Kanagawa (JP); and Satoshi Inose, Ibaraki (JP)
Assigned to HITACHI CONSTRUCTION MACHINERY CO., LTD., Tokyo (JP)
Appl. No. 17/435,717
Filed by HITACHI CONSTRUCTION MACHINERY CO., LTD., Tokyo (JP)
PCT Filed Mar. 27, 2020, PCT No. PCT/JP2020/014096
§ 371(c)(1), (2) Date Sep. 2, 2021,
PCT Pub. No. WO2020/203795, PCT Pub. Date Oct. 8, 2020.
Claims priority of application No. JP2019-066663 (JP), filed on Mar. 29, 2019.
Prior Publication US 2022/0154661 A1, May 19, 2022
Int. Cl. F02D 41/22 (2006.01); F02D 41/00 (2006.01)
CPC F02D 41/221 (2013.01) [F02D 41/0087 (2013.01); F02D 2041/224 (2013.01); F02D 2200/025 (2013.01)] 6 Claims
OG exemplary drawing
 
1. An injector failure diagnostic device for a multi-cylinder internal combustion engine having a plurality of injectors, wherein each injector injects fuel to a corresponding cylinder, said injector failure diagnostic device comprising:
an operating sound obtainment unit configured to obtain a current operating sound that is the operating sound when all of the injectors are operated, and obtain a plurality of pseudo-failure operating sounds, each of the plurality of pseudo-failure operating sounds being obtained sequentially in correspondence with stopping the fuel injection of each of the injectors, wherein each of the plurality of pseudo-failure sounds is an operating sound generated by stopping the fuel injection from one injector while maintaining the operation of the remaining injectors;
a faulty injector identification unit that receives the plurality of pseudo failure sounds and the current operating sound and is configured to compare each of the plurality of pseudo failure sounds with the current operating sound to determine whether or not any of the pseudo-failure operating sounds corresponding to each of the injectors obtained by the operating sound obtainment unit is similar to the current operating sound to identify a faulty injector; and
wherein the faulty injector identification unit calculates a similarity based on peaks observed at integer multiple components of a ratio of a primary combustion frequency of the multi-cylinder internal combustion engine to a number of the cylinders to determine whether or not the pseudo-failure operating sound corresponding to each injector is similar to the current operating sound.