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:
Aug. 18, 2020
Filed:
Oct. 29, 2018
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, Aichi-ken, JP;
Ryochi Watanabe, Susono, JP;
TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota-shi, Aichi-ken, JP;
Abstract
A wheel speed estimation device is to be applied to a four-wheel drive vehicle including a first coupling device for a rear left-wheel axle and a second coupling device for a rear right-wheel axle. These coupling devices respectively change states of engagement of a left engagement state and a right engagement state to the any one of a completely restraint state, a release state, and an incompletely restraint state. The wheel speed estimation device includes a correction parameter calculator that calculates correction parameters affected by a difference in wheel radius between wheels based on all wheel rotation speed signals, and a wheel speed calculator that calculates wheel speeds based on the wheel rotation speed signals and the correction parameters. Further, the correction parameter calculator stops calculation of the correction parameters when at least one of the left engagement state or the right engagement state is the incompletely restraint state.