The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 27, 2009
Filed:
Jul. 18, 2006
Masaru Morise, Nukata-gun, JP;
Hideki Miyata, Okazaki, JP;
Hiromichi Kimura, Okazaki, JP;
Yuji Yasuda, Nishikamo-gun, JP;
Masaru Morise, Nukata-gun, JP;
Hideki Miyata, Okazaki, JP;
Hiromichi Kimura, Okazaki, JP;
Yuji Yasuda, Nishikamo-gun, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, JP;
Abstract
A hydraulic control apparatus of a vehicular automatic transmission has a plurality of hydraulic friction engagement devices that are selectively engaged and released to establish a plurality of forward speed change stages of different speed change ratios. The forward speed change stages are achieved through engagement of predetermined friction engagement devices, of the plurality of friction engagement devices. If it is determined that a predetermined speed change stage corresponding to a predetermined shift output is not established, the hydraulic control apparatus identifies a hydraulic friction engagement device having a bad engagement that is a cause of the non-establishment of the predetermined speed change stage, on the basis of the state of engagement oil pressure of the predetermined friction engagement device.