Patent ID: 12221146

Reference numerals inFIGS.1to7are as follows: front vertically-oriented pole1, rear vertically-oriented pole2, front folding rod3, rear folding rod4, middle horizontal hinge shaft5, front horizontal hinge shaft6, rear horizontal hinge shaft7, front cross rod8, rear cross rod9, vertical hinge shaft10, cross sliding sleeve11, front connecting sleeve12, rear connecting sleeve13, rear axle14, snapping post15, damping member16, universal wheel17, rear wheel18, handrail19, storage basket assembly20; front frame member111; rear frame member113; front upper sleeve connection121; fixed groove122, rear upper sleeve connection123, pin124.

DETAILED DESCRIPTION

The structure of the foldable wagon frame provided by the present application is shown inFIG.1, including a front wheel frame and a rear wheel frame. The front wheel frame and the rear wheel frame are respectively located in two parallel vertical planes, and they are connected together by a horizontal support frame. The front wheel frame, the horizontal support frame, and the rear wheel frame form a “U”-shaped structure when the wagon frame is in the expanded configuration. The horizontal support frame includes at least two front folding rods3and at least two rear folding rods4. All the front folding rods3are hinged connected with corresponding rear folding rods4with a middle horizontal hinge shaft5.

In a specific embodiment of the present application, two front folding rods3and two rear folding rods4are provided, the two front folding rods3are in one-to-one correspondence with the two rear folding rods4, and the two front folding rods3are hinged with the two rear folding rods4through two middle horizontal hinge shafts5respectively. The front folding rods3and the rear folding rods4as connected form two folding rod mechanisms that bend or pivot in the middle about the hinge shafts5. The two folding rod mechanisms are respectively located on opposite lateral sides of the horizontal support frame. The horizontal support frame further includes a support beam perpendicular to the folding rod mechanisms, where two ends of the support beam are respectively fixedly connected with the two folding rod mechanisms. In order to ensure the strength of the horizontal support frame, support beams are preferably provided between the front folding rods3and between the rear folding rods4. As shown inFIG.1, two support beams are provided between the front folding rods3, and another two support beams are provided between the rear folding rods4. One may provide multiple front folding rods3, multiple rear folding rods4, and corresponding hinge shafts5, as required. The hinge of the front folding rods3with the rear folding rods4through the middle horizontal hinge shaft5may refer to the conventional technology. For example, the length of the middle horizontal hinge shaft5may be equal to the width of the horizontal support frame, and all the front folding rods3and all the rear folding rods4are connected with the same middle horizontal hinge shaft5to realize hinged connection. Alternatively, as shown in the drawings, a respective hinge shaft5may be provided for each front and rear folding rod.

In order to ensure the strength of the horizontal support frame, the foldable wagon frame further includes a cross-folding frame. The cross-folding frame is located below the horizontal support frame when the wagon frame is in the expanded configuration. The cross-folding frame can support the horizontal support frame to share the load borne by the horizontal support frame. As shown inFIG.6, the cross-folding frame includes a front cross rod8and a rear cross rod9. One end of the front cross rod8is preferably fixedly connected with the lower end of the front wheel frame, and another end of the front cross rod8is hingedly connected with an end of the rear cross rod9through a vertical hinge shaft10. The opposite end of the rear cross rod9(that is, the end of the rear cross rod9away from the front cross rod8) is preferably fixedly connected to the lower part of the rear wheel frame.

When the front wheel frame and the rear wheel frame are moved toward each other, as shown inFIG.3, the middle horizontal hinge shaft(s)5moves upward, and the front folding rods3and the rear folding rods4approach each other, thereby collapsing the horizontal support frame. Meanwhile, the vertical hinge shaft10moves horizontally, so that the front cross rod8and the rear cross rod9approach each other, thereby collapsing the cross-folding frame.

In an embodiment, as shown inFIG.1, the front wheel frame includes two front vertically-oriented poles1, and the rear wheel frame includes two rear vertically-oriented poles2. The lower parts of the two front vertically-oriented poles1are each sleeved with a front lower connecting sleeve12, and each front folding rod3is hinged with the corresponding front lower connecting sleeve12through a front horizontal hinge shaft6. Therefore, each front folding rod3rotates around the corresponding front horizontal hinge shaft6, so that each front folding rod3can approach the corresponding front vertically-oriented pole1when the wagon frame is folded. The front lower connecting sleeve12allows for rotation of the front vertically oriented pole1relative to the respective front folding rod3. The lower parts of the two rear vertically-oriented poles2are each sleeved with a rear lower connecting sleeve13, and each rear folding rod4is hinged with the corresponding rear connecting sleeve13through a rear horizontal hinge shaft7. When the respective rear folding rod4rotates upward around the corresponding rear horizontal hinge shaft7, the rear folding rod4approaches the corresponding rear vertically-oriented pole2when the wagon frame is folded. The rear lower connecting sleeve13allows for rotation of the rear vertically oriented pole2relative to the respective rear folding rod4. The connecting sleeves12,13may each have a tubular sleeve body. One side of the sleeve body may be provided with a hinge groove, and the respective folding rod3,4is connected with the hinge groove through the horizontal hinge shaft. In addition, a limit mechanism is provided between each folding rod and the corresponding vertically-oriented pole, and the limit mechanism can limit the maximum rotation angle of the folding rod to 90°. The structure of the limit mechanism may refer to the conventional technology.

The front wheel frame may include a front frame member111. The front frame member111may be operatively connected with the upper part of a front vertically oriented pole3with a front upper connecting sleeve121. The front upper connecting sleeve121may be sleeved on an upper part of each of the front vertically oriented poles1. The front upper connecting sleeve121may be configured to allow for rotation of the front vertically oriented pole1relative to the respective front frame member111. The rear wheel frame may include a rear frame member113. The rear frame member113may be operatively connected with the upper part of a rear vertically oriented pole2with a rear upper connecting sleeve123. The rear upper connecting sleeve123may be sleeved on an upper part of each of the rear vertically oriented poles2. The rear upper connecting sleeve123may be configured to allow for rotation of the rear vertically oriented pole2relative to the respective rear frame member113. Making reference toFIG.7, the upper connecting sleeve121,123may have a similar construction and may each include a groove122, which may be horizontal. The upper part of the each vertically-oriented pole1,2may be provided with a protruding limiter124, for instance, a screw or pin. When the vertically-oriented poles1,2rotate during the folding process, the protruding limiter124can move along the horizontal direction of the fixed groove122of each upper connecting sleeve so configured. The configuration of the pin and groove may be reversed so the pin may be on the sleeve and the groove provided on the vertically-oriented pole.

In an embodiment, as shown inFIG.3, the cross-folding frame includes two front cross rods8and two rear cross rods9. The two front cross rods8are fixedly connected to the lower ends of the two front vertically-oriented poles1, and the two rear cross rods9are fixedly connected to the lower parts of the two rear vertically-oriented poles2. When the cross rods move during the expanding and folding process, the motion of the cross rods through the respective fixed connection with the vertical pole will drive the vertically-oriented pole to rotate. So, the vertically-oriented poles and the other frame member components connected to the vertically oriented poles can be connected through the aforementioned sleeve connections12,13,121,123, and/or another mechanism such as a bearing, thereby reducing the resistance during the rotation. In the alternate, the front and rear cross rods may be operatively rotationally connected to their respective vertically oriented poles with a sleeve/bearing connection. The front cross rod8on the left lateral side of the foldable wagon frame is hinged with the rear cross rod9on the left lateral side, and the front cross rod8on the right lateral side of the foldable wagon frame is hinged with the rear cross rod9on the right lateral side. In addition, in order to ensure that the two front cross rods8and the two rear cross rods9do not interfere each other during collapsing, the front cross rod8on the left side and the rear cross rod9on the right side each have a downwardly bent section, so that a sinking section from the bent section to the end away from the front vertically-oriented pole1is formed in the front cross rod8on the left side. The height of the sinking section is lower than the front cross rod8on the right side, so that the sinking section can cross the front cross rod8on the right side. The rear cross rod9on the right side also has a sinking section, and the sinking section of the rear cross rod9on the right side can cross the rear cross rod9on the left side. The fixed connection between the cross rod and the vertically-oriented pole can improve the bearing strength of the cross-folding frame. The user may connect the vertically-oriented pole with the cross rod through a fixed connecting sleeve as required.

In addition, in order to ensure the connection strength between the front cross rod8and the rear cross rod9, the front cross rod8and the rear cross rod9are each connected with a connecting sheet extending in the horizontal direction. As shown inFIG.3andFIG.6, the front cross rod8is connected with two connecting sheets that form a yoke for a hinge connection10, so the projections of the two connecting sheets in the horizontal direction overlap. The rear cross rod9is also connected with two connecting sheets that form a yoke for a hinge connection10, and the projections of these two connecting sheets in the horizontal direction also overlap. The vertical distance between the two connecting sheets on the front cross rod8is greater than the vertical distance between the two connecting sheets on the rear cross rod9. During connection, the two connecting sheets on the rear cross rod9are inserted between the two connecting sheets of the front cross rod8, the vertical hinge shaft10is passed through the two connecting sheets on the rear cross rod9and is fixedly connected with the two connecting sheets on the front cross rod8, thereby hinging the front cross rod8with the rear cross rod9. The user may use other methods in the conventional technology to realize hinge, which is not limited here.

Further, as shown inFIG.5, a cross sliding sleeve11is provided between the two front cross rods8. The cross sliding sleeve11includes two sliding sleeves, the side walls of the two sliding sleeves are hinged, and the two front cross rods8are respectively inserted into the two sliding sleeves. When the cross-folding frame is folded or unfolded, the two front cross rods8respectively slide in the two sliding sleeves. The two rear cross rods9are also connected by another cross sliding sleeve11. The user may provide the cross sliding sleeve11only between the two front cross rods8or between the two rear cross rods9as required.

In order to ensure that the cross-folding frame can effectively support the horizontal support frame, the support beam of the horizontal support frame is provided with a snapping post15extending in the horizontal direction. As shown inFIG.3, the cross-folding frame is provided with a damping member16, and the damping member16has a snapping groove. After the horizontal support frame and the cross-folding frame are unfolded, the snapping post15can be embedded in the snapping groove, so that the horizontal support frame and the cross-folding frame are connected to form an integrated structure.

In an embodiment, the lower ends of the two front vertically-oriented poles1are respectively connected with two universal direction or swivel wheels17, and the lower ends of the two rear vertically-oriented poles2are respectively connected with two ends of a rear axle14, where the two ends of the rear axle14are each provided with a rear wheel18. Projections of the two universal direction or swivel wheels17on the rear axle14are located between the two rear wheels18. After the foldable wagon frame is folded, the two universal direction or swivel wheels17are located between the two rear wheels18. As shown inFIG.5, the two universal direction or swivel wheels17and the two rear wheels18form four support points to ensure that the foldable wagon frame as folded can be placed upright on its own.

In an embodiment, the upper ends of the two rear vertically-oriented poles2are connected with a handrail19, and the handrail19is in the shape of “U”. Two ends of the handrail19are hinged with the upper ends of the two rear vertically-oriented poles2respectively, and the handrail19can be folded to a position where it closely contacts the rear vertically-oriented poles2. The upper end of the rear vertically-oriented pole2is further provided with a limiting assembly which limits the rotation range of the handrail19to be greater than 90° and less than 180°. When the handrail19rotates to the maximum angle, the user can push the foldable wagon frame by means of the handrail19.

In an embodiment, a storage basket assembly20is further provided between the two rear vertically-oriented poles2, and the storage basket assembly20is also in the shape of “U”. Two ends of the storage basket assembly20are hinged to the middle of the two rear vertically-oriented poles2respectively. The maximum rotation angle of the storage basket assembly20is 90°. The storage basket assembly20can be connected to a storage basket made of cloth. When the storage basket assembly20is rotated to the maximum rotation angle, the storage basket can be unfolded to store items. When the storage basket is no longer used, the storage basket assembly20can be rotated to the plane where the two rear vertically-oriented poles2are located, thus reducing the space occupied by the storage basket assembly20.

In this embodiment, the foldable wagon frame is provided with a horizontal support frame and a cross-folding frame. A storage space is formed between the horizontal support frame, the front wheel frame and the rear wheel frame for storing items. The cross-folding frame is located below the horizontal support frame, and supports the horizontal support frame to ensure that the foldable wagon frame has sufficient bearing strength. Therefore, there is no need to provide connecting rods on the two sides of the foldable wagon frame, which makes the left and right sides of the storage space open, increases the space volume for storing items of the storage space, and improves the bearing capacity of the foldable wagon frame. In addition, both the horizontal support frame and the cross-folding frame can be folded and received between the front wheel frame and the rear wheel frame, so after the foldable wagon frame is folded, it occupies less space and is convenient for storage.

It should be noted that, relationship terms herein such as first and second are merely used to distinguish an entity from other entities and do not require or imply that there are any such actual relationships or sequences between these entities.

The foldable wagon frame provided by the present application has been described in detail above. The principle and the embodiments of the present application are illustrated herein by specific examples. The above description of examples is only intended to facilitate the understanding of the method and core idea of the present application. It should be noted that, for those skilled in the art, many modifications and improvements may be made to the present application without departing from the principle of the present application, and these modifications and improvements are also deemed to fall into the protection scope of the present application defined by the appended claims.