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:
Dec. 16, 1986
Filed:
Jan. 30, 1984
Kazuyoshi Iwanaga, Atsugi, JP;
Nissan Motor Company, Limited, Yokohama, JP;
Abstract
In order to ensure that an adequately high gear ratio (such as top gear) is engaged momentarily before the first gear ratio and thus reduce select shock when a manual selector valve is moved from neutral (N) to drive (D) while simultaneously enabling the provision of a flow restriction required to ensure smooth automatic upshifting, a valve which by-passes the flow restriction is provided. This by-pass valve includes a chamber provided with a drain port which is closed by a device (such as a solenoid valve) responsive to an engine associated with the transmission entering an idling condition. The chamber is supplied line pressure from the manual selector valve when the latter is moved from the N to D position so that when the engine is idling and the N-D select is made, the valve is moved to a position wherein the flow restriction is by-passed and line pressure fed unrestrictedly to the friction elements which condition the transmission to provide high gear ratio slightly before those which produce the first gear ratio. As soon as the engine ceases to idle the chamber is drained, the valve is returned to its normal position, the friction elements which produce the high gear ratio are drained and the flow restriction rendered effective again for normal automatic shifting.