US 11878729

US Patent 11,878,729: Removable Seat Attachments for Strollers

Title: Removable seat attachments for strollers

Assignee: Baby Jogger Ii LLC (Current Assignee), Baby Jogger LLC (Original Assignee)

Inventors: Mark Zehfuss

Filing Date: October 31, 2022

Issue Date: January 23, 2024

Abstract: Embodiments include strollers having removable seats. An example stroller may include rear wheels, front wheels, and a frame including a handle portion, a rear wheel support portion, a front wheel support portion and a folding mechanism connecting the front wheel support portion and the handle portion in both an unfolded configuration and in a folded configuration. The frame may include a stroller seat support portion positioned at a first vertical position adjacent the handle portion, and a front seat attachment configured for attachment to the front wheel support portion at a second vertical position substantially lower than the first vertical position. The front seat attachment may be configured to support the front stroller seat substantially over the front wheels so that a center of gravity of the stroller system is between the front wheels and the rear wheels.

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Plain-Language Overview of Independent Claims:

The patent contains three independent claims.

Independent Claim 1:
This claim describes a stroller system designed to carry multiple children. It features a main stroller frame with a handle, rear wheels, and front wheels. The frame has a primary spot for a stroller seat, located higher up near the handle. Crucially, the system also includes a "front seat attachment" that connects to the front part of the stroller frame, specifically near the front wheels, at a lower vertical position than the primary seat. This front attachment is designed to hold a second stroller seat directly over the front wheels. The goal of this arrangement is to keep the stroller stable by ensuring the overall center of gravity remains between the front and rear wheels.

Independent Claim 13:
This claim focuses on a removable seat attachment itself that can convert a single stroller into a multi-seat stroller. This attachment includes a connector that fastens to the stroller's frame and a seat support element that holds a child's seat (which could be a stroller seat, baby seat, bassinet, pram, car seat, or baby carrier). The attachment also has a folding mechanism that makes it more compact for storage. The folding mechanism works with a strut that moves a sliding connector, shifting the attachment between an extended "in-use" position and a folded "storage" position. When extended, a locking mechanism secures the attachment to the stroller. Conversely, when folded, the attachment is unlocked and can be removed.

Independent Claim 18:
This claim describes a stroller apparatus with a frame that can support multiple seats. It specifies that the frame includes a front wheel support part, a rear wheel support part, and a handle. The stroller has at least one front wheel and at least one rear wheel. A first stroller seat is either permanently or detachably connected to the frame. The key feature is the "removable seat attachment adapter," which can be detached from the frame when not needed. This adapter connects to a housing on the stroller frame and has a second end that connects to a second stroller seat. The adapter is designed to hold this second seat in front of the first seat, and importantly, the attachment point for the second seat is at a vertical height substantially below where the first stroller seat attaches to the frame. This lower positioning of the second seat is intended to improve access to the first seat from the front.

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CAFC 2026 Dockets:

A review of the scheduled cases for the U.S. Court of Appeals for the Federal Circuit (CAFC) for April, May, and June 2026, as provided by the search results, did not reveal any dockets specifically mentioning US Patent 11,878,729. The scheduled case lists provide case numbers and parties, but not specific patent numbers for all cases, making a definitive determination of all patent litigation impossible without further detailed search into each case. Therefore, based on the information available, there are no directly identifiable CAFC dockets for 2026 related to this specific patent number.