Patent Description:
The present invention relates to child stroller frames.

A child stroller apparatus is generally constructed from a frame structure that can be collapsed for storage or transport and unfolded for use. In some existing stroller frame structures, the rear wheels may be provided with a separate folding mechanism, and a caregiver has to separately operate the stroller frame and the folding mechanism of the rear wheels for collapsing the child stroller apparatus. This type of stroller frames is more cumbersome in use as it requires multiple operating steps for folding the stroller apparatus. Moreover, because the folding mechanism of the rear wheels is usually placed at a lower position, the caregiver needs to bend over to operate the folding mechanism. Document <CIT> shows a child stroller with a support member having two links and two sleeves, wherein the links are pivotably connected to the base and the sleeves are slidably connected to the base.

Therefore, there is a need for an improved stroller frame that can be more convenient in use and address at least the foregoing issues.

The present application describes a child stroller frame that can be folded and unfolded in a convenient manner. According to one aspect, the child stroller frame includes a first frame portion, a second frame portion, a pivoting part, and a linkage movably coupling the first frame portion to the pivoting part. The second frame portion has a first end and a second end, the first end of the second frame portion being pivotally connected with the first frame portion. The pivoting part has one end fixedly connected with a rear wheel support member, and another end pivotally connected with the second frame portion. The linkage includes a plurality of bars, a first one of the bars being formed integrally as a single body having a first bar portion and a second bar portion that intersect each other at an angle, the second frame portion being pivotally connected with the first bar in a region thereof where the first bar portion joins with the second bar portion, whereby the first frame portion and the rear wheel support member are movably linked for folding in a concurrent manner toward the second frame portion.

<FIG> are perspective views illustrating the invention of a child stroller frame <NUM> having a foldable rear wheel. Referring to <FIG>, the child stroller frame <NUM> includes a first frame portion <NUM>, a second frame portion <NUM>, a rear wheel support member <NUM> coupled to a rear wheel <NUM>, a pivoting part <NUM> and a linkage <NUM>.

The first frame portion <NUM> can extend upward and rearward at an angle relative to the second frame portion <NUM> when the child stroller frame <NUM> is unfolded for use, and can have a lower end provided with a front wheel <NUM>. The front wheel <NUM> may be attached at the lower end of the first frame portion <NUM> and in front of the second frame portion <NUM>.

The second frame portion <NUM> can have a front end pivotally connected with the first frame portion <NUM> and a rear end pivotally connected with the pivoting part <NUM>. According to an example of construction, the second frame portion <NUM> may include a tube segment at each of the left and right side of the child stroller frame <NUM> that is oppositely connected pivotally with the first frame portion <NUM> and the pivoting part <NUM>. The first and second frame portions <NUM> and <NUM> can rotate relative to each other for folding and unfolding the child stroller frame <NUM>.

The pivoting part <NUM> has an end fixedly connected with the rear wheel support member <NUM> and an opposite end pivotally connected with a rear end of the second frame portion <NUM>. According to an example of construction, the pivoting part <NUM> may be movable as a single body. The pivoting part <NUM> can rotate relative to the second frame portion <NUM> to fold the rear wheel support member <NUM> carried on the pivoting part <NUM> toward the second frame portion <NUM> (the folding direction is shown with arrow P in <FIG>) or unfold the rear wheel support member <NUM> away from the second frame portion <NUM>.

The linkage <NUM> movably couples the first frame portion <NUM> to the pivoting part <NUM>, whereby the first frame portion <NUM> and the rear wheel support member <NUM> carried on the pivoting part <NUM> are movably linked for folding in a concurrent manner toward the second frame portion <NUM> or unfolding in a concurrently manner away from the second frame portion <NUM>. More specifically, the linkage <NUM> can have a first and a second end opposite to each other that are respectively coupled to the first frame portion <NUM> and the pivoting part <NUM>, and an intermediate portion between the first and second ends that is pivotally connected with the second frame portion <NUM>. When the first frame portion <NUM> and the second frame portion <NUM> rotate relative to each other for folding the child stroller frame <NUM>, the pivoting part <NUM> with the rear wheel support member <NUM> carried thereon can rotate and fold toward the second frame portion <NUM> owing to the coupling of the linkage <NUM>. Accordingly, the rear wheel support member <NUM> and the rear wheel <NUM> provided thereon can be conveniently folded along with the folding of the child stroller frame <NUM> without the need for a caregiver to perform an additional step of bending over and operating the rear wheel <NUM>.

According to an embodiment, the first frame portion <NUM> includes a handle frame segment <NUM> and a front leg segment <NUM> pivotally connected with each other. The second frame portion <NUM> has a front end that may be pivotally connected with any of the handle frame segment <NUM>, the front leg segment <NUM>, or a coupling part <NUM> that pivotally connects the handle frame segment <NUM> with the front leg segment <NUM>; the linkage <NUM> has a first end that may be pivotally connected with any of the handle frame segment <NUM>, the front leg segment <NUM> or the coupling part <NUM>, a second end that is pivotally connected with the pivoting part <NUM>, and an intermediate portion between the first and second ends that is pivotally connected with the second frame portion <NUM>.

In the example shown in <FIG>, the front end of the second frame portion <NUM> is pivotally connected with the front leg segment <NUM> adjacent to a front wheel mounting portion <NUM> thereof, and the first end of the linkage <NUM> is pivotally connected with the front leg segment <NUM>. During folding of the child stroller frame <NUM>, the front leg segment <NUM> can rotate and fold toward the second frame portion <NUM> while the handle frame segment <NUM> and the front leg segment <NUM> can rotationally fold over each other. The handle frame segment <NUM> and the front leg segment <NUM> can thereby fold to lie at one same side of the second frame portion <NUM>. Moreover, the pivoting part <NUM> with the rear wheel support member <NUM> carried thereon can be urged to rotate concurrently and fold toward the second frame portion <NUM> owing to the coupling of the linkage <NUM>.

It will be appreciated that other constructions of the child stroller frame <NUM> may be possible. For example, suppose the front end of the second frame portion <NUM> is pivotally connected with the coupling part <NUM> that pivotally connects the handle frame segment <NUM> with the front leg segment <NUM>. The first end of the linkage <NUM> can be pivotally connected with the front leg segment <NUM> or the handle frame segment <NUM>. During folding of the child stroller frame <NUM>, the handle frame segment <NUM> can rotate in an anticlockwise direction (i.e., corresponding to the direction P in <FIG>) relative to the second frame portion <NUM> and fold toward the second frame portion <NUM>, while the front leg segment <NUM> can rotate in a clockwise direction (i.e., opposite to the direction P) relative to the second frame portion <NUM> and fold toward the second frame portion <NUM>. The handle frame segment <NUM> and the front leg segment <NUM> can thereby fold to respectively lie at two opposite sides of the second frame portion <NUM>. As the handle frame segment <NUM> and the front leg segment <NUM> are folded toward the second frame portion <NUM>, the linkage <NUM> can likewise cause the rear wheel support member <NUM> and the rear wheel <NUM> provided thereon to fold toward the second frame portion <NUM>.

The rear wheel support member <NUM> described herein can provide support for attachment of the rear wheel <NUM>. Various constructions may be applied for the rear wheel support member <NUM>. According to an example of construction, the rear wheel support member <NUM> may include a transversal axle to which are attached two rear wheels <NUM>. According to another example of construction, the rear wheel support member <NUM> may include a wheel mount to which is attached one rear wheel <NUM>, two separate sets of the rear wheel support member <NUM> and the rear wheel <NUM> being respectively provided at the left and right sides of the second frame portion <NUM>.

Referring to <FIG>, the linkage <NUM> can include a first bar assembly <NUM> and a second bar assembly <NUM>. The first bar assembly <NUM> can be respectively connected pivotally with the second frame portion <NUM> and the pivoting part <NUM>, wherein the first bar assembly <NUM>, the pivoting part <NUM> and the second frame portion <NUM> can be configured to form a first bar linkage portion. The second bar assembly <NUM> can be respectively coupled to the first bar assembly <NUM> and the first frame portion <NUM>. According to the invention the first bar assembly <NUM> includes a first bar <NUM> pivotally connected with the second frame portion <NUM>, and the second bar assembly <NUM> is respectively connected pivotally with the first bar <NUM> and the first frame portion <NUM>. The second bar assembly <NUM>, the first bar <NUM>, the first frame portion <NUM> and the second frame portion <NUM> can be configured to form a second bar linkage portion. A relative rotation between the first frame portion <NUM> and the second frame portion <NUM> in a folding direction causes the first bar <NUM> to rotate relative to the second frame portion <NUM>, which results in the first bar linkage portion to fold and the pivoting part <NUM> to rotate for folding the rear wheel support member <NUM> toward the second frame portion <NUM>. In other words, the first and second bar assemblies <NUM> and <NUM> are operable to drive the rear wheel support member <NUM> to fold toward the second frame portion <NUM> when the first frame portion <NUM> rotates relative to the second frame portion <NUM> in a folding direction.

Referring to <FIG>, the first bar assembly <NUM> and the second bar assembly <NUM> may be located at an inner side of the pivoting part <NUM> to prevent environment interference during use. According to an example of construction, two sets of the first and second bar assemblies <NUM> and <NUM> can be symmetrically provided at the left and right sides of the child stroller frame <NUM>. Moreover, the child stroller frame <NUM> may further include a seat mount <NUM> for installation of a detachable child seat <NUM>. The installed child seat <NUM> may be collapsed along with the child stroller frame <NUM> into a compact form at an inner side of the child stroller frame <NUM>.

Referring to <FIG>, the first bar assembly <NUM> includes a plurality of bars. The first bar assembly <NUM>, the second frame portion <NUM> and the pivoting part <NUM> are configured to form a first bar linkage portion adapted to fold the pivoting part <NUM> and the rear wheel support member <NUM> carried thereon toward the second frame portion <NUM> during folding of the child stroller frame <NUM>. For example, the first bar assembly <NUM>, the second frame portion <NUM> and the pivoting part <NUM> may be configured to form a four-bar linkage. According to an example of construction, the first bar assembly <NUM> can include the first bar <NUM> and a second bar <NUM>, the second bar <NUM> having two opposite ends respectively connected pivotally with the first bar <NUM> and the pivoting part <NUM>. The first and second bars <NUM> and <NUM> of the first bar assembly <NUM>, the second frame portion <NUM> and the pivoting part <NUM> can form the first bar linkage portion that is operable to cause the pivoting part <NUM> and the rear wheel <NUM> carried thereon to fold toward the second frame portion <NUM>. More specifically, a rotation of the first bar <NUM> relative to the second frame portion <NUM> in a folding direction can cause the second bar <NUM> to move and urge the pivoting part <NUM> to rotate relative to the second frame portion <NUM> in the direction P for folding toward the second frame portion <NUM>. The second bar <NUM> can have a shape <NUM> configured to achieve compact folding and prevent obstructing interference with the pivoting part <NUM> and/or the rear wheel support member <NUM> during folding movement. For example, the shape <NUM> of the second bar <NUM> may include a curved profile with a concavity facing downward.

Referring to <FIG>, the second bar assembly <NUM> can include one or a plurality of bars. The second bar assembly <NUM>, the first bar <NUM>, the first frame portion <NUM> and the second frame portion <NUM> can be configured to form a second bar linkage portion. According to an example of construction, the second bar linkage portion may be a four-bar linkage. For example, the second bar assembly <NUM> can include a third bar <NUM> having two opposite ends respectively connected pivotally with the first bar <NUM> and the first frame portion <NUM>. The first bar <NUM>, the third bar <NUM>, the first frame portion <NUM> and the second frame portion <NUM> can thereby form the second bar linkage portion.

Referring to <FIG>, the first bar <NUM> has two bar portions <NUM> and <NUM> that intersect each other at an angle. The first bar <NUM> including the bar portions <NUM> and <NUM> is formed integrally as a single body. According to an example of construction, the bar portion <NUM> may have an elongate shape with a length greater than the length of the bar portion <NUM>. The first bar <NUM> is pivotally connected with the second bar assembly <NUM> at an end of the bar portion <NUM>, and the bar portion <NUM> extends at an angle from the bar portion <NUM> toward the second bar <NUM> and pivotally connect with the second bar <NUM>. According to an example of construction, the second bar <NUM> has a nonlinear shape, and the shape and/or length of the bar portion <NUM> may be configured in accordance with the desired folding shape of the first and second bars <NUM> and <NUM> so that the first bar linkage portion can be collapsed into a smaller volume. According to an example of construction, the pivot connection between the first bar <NUM> and the second frame portion <NUM> can be located at the joining region between the two bar portions <NUM> and <NUM>. According to an example of implementation, the bar portion <NUM> of the first bar <NUM>, the second bar <NUM>, the second frame portion <NUM> and the pivoting part <NUM> can form a first bar linkage portion; the bar portion <NUM> of the first bar <NUM>, the third bar <NUM>, the second frame portion <NUM> and the first frame portion <NUM> can form a second bar linkage portion.

Moreover, a limiting structure <NUM> can be disposed between the bar portion <NUM> and the second bar assembly <NUM>. According to an example of construction, the limiting structure <NUM> can include a limiting joint pivotally coupling the bar portion <NUM> of the first bar <NUM> to the third bar <NUM>. When the child stroller frame <NUM> is in an unfolded state for use, the bar portion <NUM> of the first bar <NUM> and the second bar assembly <NUM> (in particular the third bar <NUM> thereof) can form a substantially straight shape that extends between the first frame portion <NUM> and the second frame portion <NUM> and can provide stable support for the first frame portion <NUM>. According to an example of construction, the first bar <NUM> can have a L-shape.

Exemplary operation of the child stroller frame <NUM> is described hereinafter with reference to <FIG>. When the child stroller frame <NUM> is to be collapsed, the first frame portion <NUM> can be rotated for folding relative to the second frame portion <NUM>. More specifically, the front leg segment <NUM> can rotate and fold toward the second frame portion <NUM>, which results in folding of the second bar linkage portion. As the second bar linkage folds, the first bar <NUM> rotates relative to the second frame portion <NUM>, which actuates the first bar linkage portion so that the pivoting part <NUM> rotates in the direction P and folds toward the second frame portion <NUM>. As a result, the rear wheel support member <NUM> can be displaced by the pivoting part <NUM> to a position adjacent to the second frame portion <NUM> and in front of the pivot connection between the second frame portion <NUM> and the pivoting part <NUM>. Moreover, the handle frame segment <NUM> can rotate and fold over the front leg segment <NUM> so that the size of the first frame portion <NUM> can be reduced and the child seat <NUM> can be positioned compactly at an inner side of the folded child stroller frame <NUM>.

When the child stroller frame <NUM> is to be unfolded for use, the handle frame segment <NUM>, the front leg segment <NUM> and the second frame portion <NUM> can be reversely rotated relative to one another, which causes the pivoting part <NUM> to rotate and unfold from the second frame portion <NUM> owing to the first and second bar linkage portions. As a result, the rear wheel support member <NUM> can be displaced by the pivoting part <NUM> to a position away from the second frame portion <NUM> and behind the pivot connection between the second frame portion <NUM> and the pivoting part <NUM>.

Since the rear wheel support member <NUM> is movably linked to the child stroller frame <NUM>, the rear wheel support member <NUM> may be held in the unfolded or folded state without the need of providing an additional locking mechanism for locking the rear wheel support member <NUM> in position relative to the second frame portion <NUM>.

Advantages of the structures described herein include the ability to provide a child stroller frame that has a foldable rear wheel support member, whereby the child stroller frame can be folded into a compact form. The rear wheel support member can be movably coupled to the other frame portions of the child stroller frame with a linkage, thereby allowing the entire stroller frame to fold and unfold in a convenient manner.

Claim 1:
A child stroller frame (<NUM>) comprising:
a first frame portion (<NUM>) and a second frame portion (<NUM>), the second frame portion (<NUM>) having a first end and a second end, the first end of the second frame portion (<NUM>) being pivotally connected with the first frame portion (<NUM>);
a pivoting part (<NUM>) having one end fixedly connected with a rear wheel support member (<NUM>) and another end pivotally connected with the second frame portion (<NUM>); and
a linkage (<NUM>) movably coupling the first frame portion (<NUM>) to the pivoting part (<NUM>), wherein the linkage (<NUM>) includes a plurality of bars (<NUM>, <NUM>, <NUM>), a first one (<NUM>) of the bars being formed integrally as a single body having a first bar portion (<NUM>) and a second bar portion (<NUM>) that intersect each other at an angle, the second frame portion (<NUM>) being pivotally connected with the first bar (<NUM>) in a region thereof where the first bar portion (<NUM>) joins with the second bar portion (<NUM>), whereby the first frame portion (<NUM>) and the rear wheel support member (<NUM>) are movably linked for folding in a concurrent manner toward the second frame portion (<NUM>).