# US 12,179,681 B2 · Lower limb restraint airbag device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,179,681 B2 - Document ID: US12179681B2 - Status: Granted - Kind: B2 - Application number: 18/378,683 - Filed: 2023-10-11 - Published: 2024-05-02 - Granted: 2024-12-31 - Earliest claimed: 2022-10-31 - Assignees: Toyota Jidosha Kabushiki Kaisha - Applicants: Toyota Jidosha Kabushiki Kaisha - Inventors: Mitsuyoshi Ohno - Web page: https://patentgrep.com/patent/US12179681B2 ## CPC - B60R 21/055: Padded {or energy-absorbing} fittings {, e.g. seat belt anchors (sun visors B60J3/00; head rests B60N2/80)} - B60R 21/206: in the lower part of dashboards, e.g. for protecting the knees - B60R 21/231: characterised by their shape, construction or spatial configuration - B60R 21/2338: Tethers - B60R 21/264: using instantaneous generation of gas, e.g. pyrotechnic (B60R21/268 takes precedence) - B60R 2021/0051: {Knees} - B60R 2021/23107: {the bag being integrated in a multi-bag system} - B60R 2021/23169: {specially adapted for knee protection} - B60R 2021/23386: {External tether means} - B60R: VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR ## Abstract A lower limb restraint airbag device, including: an airbag that is configured to be inflated and deployed toward a knee and a shin of a passenger seated in a vehicle seat by gas ejected from an inflator, and to make contact with at least the knee; a reaction force plate that is configured to be pulled out to a seat front side of the airbag in conjunction with inflation and deployment of the airbag; and a lock mechanism that is configured to block movement toward a seat front side of the pulled out reaction force plate. ## Claims ### Claim 1 A lower limb restraint airbag device, comprising: an airbag that is configured to be inflated and deployed toward a knee and a shin of a passenger seated in a vehicle seat by gas ejected from an inflator, and to make contact with at least the knee; a reaction force plate that is configured to be pulled out to a seat front side of the airbag in conjunction with inflation and deployment of the airbag; and a lock mechanism that is configured to block movement toward a seat front side of the pulled out reaction force plate, wherein one each of the inflator, the airbag, the reaction force plate, and the lock mechanism is provided for a left knee and for a right knee of the passenger and is installed at respective side walls disposed at the left and right sides of the vehicle seat, and wherein the reaction force plates are swingably supported by the side walls and are linked to the airbags by straps. ### Claim 2 (depends on 1) The lower limb restraint airbag device of claim 1, wherein: the lock mechanism includes a lock bar having a one-end portion slidably retained in a guide groove formed at the side wall and having an other-end portion swingably attached to the reaction force plate; and the guide groove includes a recess that immovably houses the one-end portion of the lock bar after the reaction force plate has been pulled out. ### Claim 3 (depends on 1) The lower limb restraint airbag device of claim 1, wherein: the lock mechanism includes: a striker that is provided at one of the reaction force plates, and a hook that is provided at the other of the reaction force plates and that is configured to anchor to the striker; and the reaction force plate provided with the hook is configured to swing with a delay relative to the reaction force plate provided with the striker. ### Claim 4 (depends on 3) The lower limb restraint airbag device of claim 3, wherein the reaction force plate provided with the hook is heavier than the reaction force plate provided with the striker. ### Claim 5 (depends on 3) The lower limb restraint airbag device of claim 3, wherein an ignition timing of the inflator that ejects gas into the airbag linked by the strap to the reaction force plate provided with the hook is delayed relative to an ignition timing of the inflator that ejects gas into the airbag linked by the strap to the reaction force plate provided with the striker. ### Claim 6 (depends on 1) The lower limb restraint airbag device of claim 1, wherein: the lock mechanism includes: a striker that is provided at one of the reaction force plates, and a hook that is provided swingably at the other of the reaction force plates and that is configured to anchor to the striker; and the hook is configured to swing and be anchored to the striker after the reaction force plate provided with the striker and the reaction force plate provided with the hook have been pulled out. ### Claim 7 (depends on 1) The lower limb restraint airbag device of claim 1, wherein the side walls are configured movably in the seat front-rear direction, with a rear end of the side walls disposed further toward a seat front side than a front end of a seat cushion of the vehicle seat while a vehicle is traveling, and with a front end of the side walls disposed either at a same position as, or further toward a seat rear side than, the front end of the seat cushion of the vehicle seat when a passenger is boarding or alighting. ### Claim 8 (depends on 7) The lower limb restraint airbag device of claim 7, wherein the side walls are configured to move toward the seat front side in conjunction with reclining of a seatback of the vehicle seat. ### Claim 9 (depends on 8) The lower limb restraint airbag device of claim 8, wherein the side walls are configured to move toward the seat front side in conjunction with reclining of a seatback of the vehicle seat by a specific angle or greater. ### Claim 10 (depends on 7) The lower limb restraint airbag device of claim 7, configured such that a seatback of the vehicle seat is not able to be reclined unless the rear end of the side walls is disposed further toward the seat front side than the front end of the seat cushion of the vehicle seat. ### Claim 11 (depends on 10) The lower limb restraint airbag device of claim 10, wherein a warning alarm is generated when a travel speed of the vehicle exceeds a specific speed and the left and right side walls continue to be disposed toward the seat rear side when the seatback is reclined or when a seatbelt is not being worn. ### Claim 12 (depends on 7) The lower limb restraint airbag device of claim 7, wherein only a side wall on a side door side of the respective side walls is configured movably. ### Claim 13 A lower limb restraint airbag device, comprising: an airbag that is configured to be inflated and deployed toward a knee and a shin of a passenger seated in a vehicle seat by gas ejected from an inflator, and to make contact with at least the knee; a reaction force plate that is configured to be pulled out to a seat front side of the airbag in conjunction with inflation and deployment of the airbag; and a lock mechanism that is configured to block movement toward a seat front side of the pulled out reaction force plate, wherein one each of the inflator, the airbag, the reaction force plate, and the lock mechanism is provided for a left knee and for a right knee of the passenger and is installed at respective side walls disposed at the left and right sides of the vehicle seat, and wherein the side walls are configured movably in the seat front-rear direction, with a rear end of the side walls disposed further toward a seat front side than a front end of a seat cushion of the vehicle seat while a vehicle is traveling, and with a front end of the side walls disposed either at a same position as, or further toward a seat rear side than, the front end of the seat cushion of the vehicle seat when a passenger is boarding or alighting. ### Claim 14 (depends on 13) The lower limb restraint airbag device of claim 13, wherein the side walls are configured to move toward the seat front side in conjunction with reclining of a seatback of the vehicle seat. ### Claim 15 (depends on 13) The lower limb restraint airbag device of claim 13, configured such that a seatback of the vehicle seat is not able to be reclined unless the rear end of the side walls is disposed further toward the seat front side than the front end of the seat cushion of the vehicle seat.