Frame Folding Mechanism, Frame Locking Mechanism, Backrest Unlocking Mechanism and Stroller Collapsing a Pram in One Movement

This patent describes a linked set of mechanisms inside a stroller: a frame folding mechanism, a frame locking mechanism and a backrest unlocking mechanism, arranged so the frame, backrest and seat collapse together instead of one at a time. It comes from Wonderland Switzerland AG, part of the Wonderland Group, one of the world’s largest nursery products manufacturers.

The Problem

Parents want two things from a pram that pull in opposite directions. In use it should be comfortable and safe for the child, which means a substantial frame, a reclining backrest and a proper seat. Out of use it should shrink, so it fits in a car boot, a hallway or an apartment cupboard, and so it is not an embarrassment to store.

A conventional stroller has a frame, a backrest and a seat portion, with the backrest and seat mounted on the frame. Folding it usually means operating each of those separately: release the backrest, deal with the seat, then collapse the frame. The specification is blunt about the consequence, describing the folding operation of such strollers as complicated and inconvenient. Anyone who has tried to do it one-handed while holding a child, in the rain, beside a car in a supermarket car park, will recognise the complaint. An awkward fold is not merely annoying; it is the point at which fingers get caught and at which a frame that has not fully latched can collapse unexpectedly later.

What This Invention Does

The application covers three mechanisms and the stroller that combines them. The frame folding mechanism handles the collapse of the frame itself. The frame locking mechanism holds the frame rigid when it is open, which is the safety-critical function, since an unlocked frame under load is what causes an unintended fold. The backrest unlocking mechanism releases the backrest so it can travel with the rest of the structure.

The point of describing them together is that they are coupled. By linking the backrest unlocking action into the frame folding action, the stroller can be brought down without separately operating the backrest and the seat portion, which is what turns a multi-step procedure into a single movement. The corresponding benefits set out in the specification are a smaller folded volume, tidier appearance, space saving and convenient storage, achieved without giving up the comfort and safety expected while the child is in the seat.

Key Features

• Frame folding mechanism. A mechanism dedicated to collapsing the stroller frame.
• Frame locking mechanism. A locking mechanism holds the frame rigid in the open position.
• Backrest unlocking mechanism. The backrest is released by its own mechanism as part of the fold.
• Coupled operation. The mechanisms work together so the frame, backrest and seat need not be operated separately.
• Reduced folded volume. The stroller collapses into a smaller package for storage and transport.
• Complete stroller claimed. The application covers the stroller incorporating the mechanisms, not only the mechanisms alone.

Who Is Behind It

The applicant is Wonderland Switzerland AG, based in Steinhausen, Switzerland, the European arm of the Wonderland Group, a nursery goods manufacturer established in 1983 with operations across Asia, Europe, North America and Australia and more than 12,000 employees. The group manufactures car seats, strollers, travel cots and highchairs, including for well-known consumer brands. The named inventors are Jialiang Yuan and Zhengwen Guo. The application is a divisional of Australian application 2024205769, with priority from January 2020.

Why It Matters

Prams are one of the few products almost every family buys, and they are also regulated safety items: in Australia, prams and strollers must comply with the mandatory standard administered by the Australian Competition and Consumer Commission, which covers requirements including brakes, tethers and, relevantly here, protection against unintended folding and finger entrapment. Mechanisms that reduce the number of separate actions in a fold cut down the opportunities for a parent to leave something unlatched. The commercial dimension is just as real, since folded size is one of the first specifications a shopper compares, and it determines whether a pram fits the boot of a small car.

Related Concepts

• Baby transport – the product category this stroller belongs to.
• Linkage (mechanical)) – the engineering principle behind coupled folding mechanisms.
• Latch – the locking function that keeps the open frame rigid.
• Product safety standards – the Australian mandatory standards regime for prams and strollers.
• Ergonomics – the usability discipline behind one-motion folding.
• Child safety seat – an adjacent regulated product category from the same manufacturer.

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AU 2026202040 was published in the Australian Official Journal of Patents on 2 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.