VEHICLE SEAT

• US 20120212015A1
• Filed: 02/17/2011
• Published: 08/23/2012
• Est. Priority Date: 02/17/2011
• Status: Active Grant

• Current Assignee: Tachi-S Company Limited
• Original Assignee: Tachi-S Company Limited
• Inventors: Ozawa, Hitoshi
• Granted Patent: US 8,596,721 B2
• Time in Patent Office: Days
• US Class Current: 297/216.1
• CPC Class Codes: B60N 2/1615 Parallelogram-like structure
• CPC Class Codes: B60N 2/165 Gear wheel driven mechanism

Abstract

In a vehicle seat, two front and two rear links are pivotally connected between a seat cushion frame and a floor of vehicle. Each of the two front links has an arcuate gear region meshed with a corresponding pinion provided to the seat cushion at a point backwardly of that arcuate gear region. Two connecting links are pivotally connected between the respective two front and rear links, such that forward pivot points respective of the two connecting links in the respective two front links are always maintained forwardly of the respective pinions, irrespective of vertical rotation of the two front links. In the case of rear-end collision, such link arrangement allows an excessive backward and downward load to be transmitted through the two connecting links and front links to the two lateral sides of seat cushion frame and dispersed therein, thereby absorbing a corresponding excessive impact.

Claims

1. A vehicle seat in combination with a floor of vehicle, comprising:

a seat cushion frame including a first lateral frame member and a second lateral frame member, wherein said first lateral frame member has a forward portion facing forwardly of the vehicle and a backward portion facing backwardly of the vehicle, whereas said second lateral frame member has a forward portion facing forwardly of the vehicle and a backward portion facing backwardly of the vehicle,

a drive pinion rotatably provided to said first lateral frame member, said drive pinion being operatively connected with a drive source;

a first front link element so formed to have;

a lower end portion pivotally secured on said floor of vehicle;

an upper end portion pivotally connected with said forward portion of said first lateral frame member; and

an arcuate gear region defined between said lower and upper end portions, said arcuate gear region being in a meshed engagement with said drive pinion and so arranged as to face backwardly of the seat;

said first front link element being movable vertically towards and away from said floor of vehicle;

said drive pinion being disposed backwardly of said first front link element;

a second front link element having;

an upper portion including a pivotal connection point pivotally connected with said forward portion of said second lateral frame member; and

a lower end portion pivotally secured on said floor of vehicle;

a first rear link element having;

an upper end portion pivotally connected with said backward portion of said first lateral frame member; and

a lower end portion pivotally secured on said floor of vehicle;

a second rear link element having;

an upper end portion pivotally connected with said backward portion of said second lateral frame member; and

a lower end portion pivotally secured on said floor of vehicle;

a first connecting link element which is at the forward end portion thereof pivotally connected with said upper portion of said first front link element, while being at the backward end portion thereof pivotally connected with said upper end portion of said first rear link element; and

a second connecting link element which is at the forward end portion thereof pivotally connected with said upper portion of said second front link element, while being at the backward end portion thereof pivotally connected with said upper end portion of said second rear link element,

wherein operation of said drive source causes rotation of said drive pinion, which in turn causes vertical rotative displacement of said first and second front link elements as well as of said first and second rear link elements, thereby raising and lowering the vehicle seat, and

wherein said forward end portion of said first connecting link element and said first front link element are arranged such that, even during said vertical rotative displacement of said first front link element, a pivotal connection point where said forward end portion of said first connecting link element is pivotally connected with said upper portion of said first front link element is maintained forwardly of a meshed engagement point where said drive pinion is in meshed engagement with said arcuate gear region of said first front link element.

2. The vehicle seat as claimed in claim 1, wherein said forward end portion of said first connecting link element and said first front link element are arranged such that said pivotal connection point therebetween is also maintained above said drive pinion, even during said vertical rotative displacement of said first front link element, wherein a connecting element is rotatably extended between said first and second lateral frame members, and wherein said first front link element is at the pivotal connection point thereof fixedly connected with said connecting element and said second front link element is also at the pivotal connection point thereof fixedly connected with said connecting element, so that said first and second front link elements are at the respective upper portions thereof rotatable in synchronized way relative to said connecting element.

3. The vehicle seat as claimed in claim 1, wherein a free-to-rotate pinion is rotatably provided to said second lateral frame member, wherein said second front link element has a widened area defined in the upper portion thereof and an arcuate gear region defined in said widened area, said arcuate gear region being in a meshed engagement with said free-to-rotate pinion and so arranged as to face backwardly of the seat, wherein said free-to-rotate pinion is disposed backward of said arcuate gear region of said second front link element, while being in meshed engagement therewith, wherein said forward end portion of said second connecting link element and said second front link element are arranged such that, even during said vertical rotations of said second front link element, a pivotal connection point where said forward end portion of said second connecting link element is pivotally connected with said upper portion of said second front link element is maintained forwardly of a meshed engagement point where said free-to-rotate pinion is in meshed engagement with said arcuate gear region of said second front link element, and wherein said first link element is at the pivotal connection point thereof fixedly connected with said connecting element and said second front link element is also at the pivotal connection point thereof fixedly connected with said connecting element, so that said first and second front link elements are at the respective upper portions thereof rotatable in synchronized way relative to said connecting element.

4. The vehicle seat as claimed in claim 3, wherein said forward end portion of said second connecting link element and said second front link element are arranged such that said pivotal connection point therebetween is also maintained above said drive pinion, even during said vertical rotative displacement of said second front link element.