CN114750818B

CN114750818B - Child trailer

Info

Publication number: CN114750818B
Application number: CN202210270995.8A
Authority: CN
Inventors: 张兴荣; 石平中
Original assignee: Goodbaby Child Products Co Ltd
Current assignee: Goodbaby Child Products Co Ltd
Priority date: 2022-03-18
Filing date: 2022-03-18
Publication date: 2023-08-04
Anticipated expiration: 2042-03-18
Also published as: CN114750818A

Abstract

The invention discloses a child trailer which comprises a frame and a plurality of groups of wheel assemblies arranged at the bottom of the frame, wherein each group of wheel assemblies comprises a wheel frame and a wheel body arranged at the bottom of the wheel frame in a rotating mode around a wheel shaft, the wheel frame is connected to the frame in a rotating mode, a linkage mechanism used for linking the wheel assemblies to turn over is arranged between the frame and the wheel body, the linkage mechanism at least comprises a linkage rod, one end portion of the linkage rod is connected with the frame in a universal rotating mode, the other end portion of the linkage rod is connected with the wheel frame in a universal rotating mode, and in the process of converting the child trailer from the unfolded state to the folded state, the linkage mechanism drives the wheel assemblies to turn over in the up-down direction relative to the frame and fold in the frame, so that the overall size of the child trailer after being folded is greatly reduced, and convenience is provided for daily storage and carrying of users.

Description

Child trailer

Technical Field

The invention relates to the field of children supplies, in particular to a children trailer.

Background

In order to reduce the folded storage space for easy storage and carrying, the existing child trailers are mostly provided with a foldable structure. The existing children's trailer generally includes collapsible main frame, sets up at the anterior front wheel subassembly of main frame bottom and sets up at the rear wheel subassembly of main frame bottom rear portion to and can supply the tow bar of operation of dragging, at present, children's trailer is folding back, only has folded main frame, and front wheel subassembly and rear wheel subassembly still are located the bottom of the main frame after folding, have taken great size space, have influenced children's trailer folding back overall size's reduction.

Disclosure of Invention

It is an object of the present invention to provide a new child trailer to solve one or more of the problems of the prior art.

In order to achieve the above purpose, the invention adopts the following technical scheme: the utility model provides a children's trailer, has expansion state and folding state, children's trailer includes the frame, locates the multiunit wheel subassembly of frame bottom, every group the wheel subassembly all includes the wheel carrier and sets up rotationally around the axle the wheel body of wheel carrier bottom, the wheel carrier rotationally connect in on the frame, the frame with be provided with between the wheel body and be used for the linkage the link gear of wheel subassembly upset, the link gear includes the gangbar at least, one end of gangbar with the frame is connected rotationally in universal, another end of gangbar with the wheel carrier is connected rotationally in universal, children's trailer is by expansion state to folding state's in-process, the link gear order about the wheel subassembly is along the upset of upper and lower direction and draw in the frame.

Preferably, in the unfolded state of the child trailer, the wheel axle extends in the left-right direction; when the child trailer is in a folded condition, the axle extends in a fore-aft direction.

Preferably, the multiple groups of wheel assemblies comprise two groups of front wheel assemblies arranged on the left side and the right side of the front part of the frame bottom and two groups of rear wheel assemblies arranged on the left side and the right side of the rear part of the frame bottom, when the child trailer is in a folded state, the two groups of front wheel assemblies are arranged side by side along the left-right direction, the two groups of rear wheel assemblies are arranged side by side along the left-right direction, and the front wheel assemblies and the rear wheel assemblies on the same side of the frame are arranged in an overlapping manner along the front-rear direction.

Preferably, connectors are arranged at two ends of the linkage rod in the length direction, and the two ends of the linkage rod are respectively connected with the wheel frame and the vehicle frame in a universal rotation manner through the connectors, wherein the connectors are spherical joint pieces.

Preferably, the wheel frame is rotatably connected with the frame around a rotation center line, and the rotation center line extends along the front-rear direction when the child trailer is in a unfolded state; the child trailer is in a folded condition, with the centre line of rotation extending from top to bottom.

Preferably, the frame comprises two groups of side frames which are respectively arranged on the front side and the rear side and extend along the up-down direction, an upper surrounding frame which is rotationally arranged between the upper parts of the two groups of side frames, and a lower surrounding frame which is rotationally arranged between the lower parts of the two groups of side frames, wherein the upper surrounding frame and the lower surrounding frame respectively extend along the front-rear direction and can be respectively arranged in a folding manner along the front-rear direction, the wheel frame is rotationally arranged on the lower surrounding frame, the linkage rod is rotationally arranged between the wheel frame and the side frames, and the lower surrounding frames are linked when being folded along the front-rear direction so as to enable the wheel assembly to turn over.

In some embodiments, the lower enclosure frame comprises a first lower frame and a second lower frame which can be folded in a relative rotation manner, the rear part of the first lower frame is connected with the front part of the second lower frame in a relative rotation manner, the plurality of groups of wheel assemblies comprise two groups of front wheel assemblies arranged on the left and right sides of the front part of the first lower frame bottom, two groups of rear wheel assemblies arranged on the left and right sides of the rear part of the second lower frame bottom, the two groups of front wheel assemblies are folded in a relative overturning manner in the process of converting the unfolded state into the folded state, the two groups of rear wheel assemblies are folded in a relative overturning manner, and the lower enclosure frame is folded in the front-rear direction so that the front wheel assemblies and the rear wheel assemblies are folded between the first lower frame and the second lower frame in the front-rear direction.

In some embodiments, the first lower frame includes two first lower surrounding rods that are respectively disposed at the left and right sides and all extend along the front and rear directions, the second lower frame includes two second lower surrounding rods that are respectively disposed at the left and right sides and all extend along the left and right directions, the wheel frame of the front wheel assembly can be rotationally disposed on the first lower surrounding rods around the axis of the first lower surrounding rods, and the wheel frame of the rear wheel assembly can be rotationally disposed on the second lower surrounding rods around the axis of the second lower surrounding rods.

In some embodiments, the lower frame further comprises a lower connecting piece on each side of the frame, the rear part of the first lower surrounding rod is rotatably connected to the lower connecting piece around a first shaft, the front part of the second lower surrounding rod is rotatably connected to the lower connecting piece around a second shaft, the first shaft and the second shaft extend along the left-right direction and are arranged in parallel with each other, and a limiting structure for limiting the downward rotation position of the first lower surrounding rod and the second lower surrounding rod is further arranged on the lower connecting piece.

In some embodiments, a set of said linkage bars are rotatably disposed between said wheel frame and said side frame of the front side of each said front wheel assembly; a group of linkage rods are rotatably arranged between the wheel frame of each rear wheel assembly and the side frame at the rear side.

In some embodiments, the upper frame comprises a first upper frame, an upper connecting piece and a second upper frame which are sequentially connected in a rotating manner from front to back, the lower frame comprises a first lower frame, a lower connecting piece and a second lower frame which are sequentially connected in a rotating manner from front to back, the child trailer is in a folded state, the first upper frame, the first lower frame and the side frames on the front side are mutually folded, the second upper frame, the second lower frame and the side frames on the rear side are mutually folded, the lower connecting piece is positioned above the upper connecting piece, and all wheel assemblies are overturned and folded into a space formed by the upper frame, the lower frame and the two groups of side frames.

Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages: according to the child trailer disclosed by the invention, the frame can be turned over and folded relative to the frame in the folding process, so that the wheel assemblies are turned over in the up-down direction in the folding process of the frame and folded in the folded frame, the height of the folded trailer frame is greatly reduced compared with that of the trailer frame before folding, the overall size of the folded child trailer is greatly reduced, and convenience is brought to daily storage and carrying of users.

Drawings

FIG. 1 is a schematic perspective view of a child trailer in an unfolded state according to an embodiment of the present invention;

FIG. 2 is a schematic side elevational view of the child trailer of FIG. 1;

FIG. 3 is a schematic perspective view of the child trailer of FIG. 1 during folding;

FIG. 4 is a schematic side elevational view of the child trailer of FIG. 3;

FIG. 5 is a schematic rear view of the child trailer of FIG. 3;

FIG. 6 is a schematic perspective view of the child trailer of FIG. 1 in a collapsed condition;

FIG. 7 is a schematic side elevational view of the child trailer of FIG. 6;

FIG. 8 is a schematic rear view of the child trailer of FIG. 6;

wherein: 1. a first side enclosure frame; 2. a second side frame; 3. a lower surrounding frame; 31. a first lower frame; 311. a first lower surrounding rod; 312. a first lower cross bar; 32. a second lower frame; 321. a second lower enclosing rod; 322. a second bottom rail; 33. a lower connecting piece; 34. a first shaft; 35. a second shaft; 4. an upper surrounding frame; 41. a first upper frame; 411. a first upper surrounding rod; 42. a second upper frame; 421. a second upper surrounding rod; 43. an upper connecting piece; 44. a third shaft; 45. a fourth shaft; 5. a front wheel assembly; 51. a front wheel frame; 52. a front wheel; 53. a front axle; 6. a rear wheel assembly; 61. a rear wheel frame; 62. a rear wheel; 63. a rear axle; 7. a front linkage rod; 7a, a front connector; 8. a rear link lever; 8a, a rear connector; 9. a towing bar.

Detailed Description

The technical scheme of the invention is further described below with reference to the attached drawings and specific embodiments.

The following description of the front, rear, left, right, up, down, etc. orientations are defined with reference to the orientations that an operator observes while towing the child trailer in the unfolded state, and the reference definition of the orientations is mainly aimed at more clearly explaining the relative positional relationship between the lever members.

Referring to fig. 1 and 2, a child trailer is shown having an unfolded state and a folded state. The children trailer comprises a frame and a plurality of groups of wheel assemblies arranged at the bottom of the frame, each group of wheel assemblies comprises a wheel frame and a wheel body rotationally arranged at the bottom of the wheel frame around a wheel shaft, wherein the wheel frame is rotationally connected to the frame, a linkage mechanism for overturning the driving wheel assemblies is arranged between the frame and the wheel body, the linkage mechanism comprises a linkage rod, one end part of the linkage rod is connected to the frame in a universal rotation manner, and the other end part of the linkage rod is connected to the wheel frame of the wheel assemblies to be linked in a universal rotation manner. In the folding process of the frame, the linkage mechanism drives all wheel assemblies to turn over along the up-down direction relative to the frame and fold in the frame, wherein the wheel shafts of all wheel assemblies extend along the left-right direction when the child trailer is in an unfolding state; when the child trailer is converted to a collapsed condition, the axles of the wheel assemblies are converted to extend in a fore-aft direction.

Referring to fig. 1 and 2, in particular, the multi-wheel assembly includes a front wheel assembly 5 provided at a front portion of a frame bottom, a rear wheel assembly 6 provided at a rear portion of the frame bottom, the front wheel assembly 5 including a front wheel frame 51 extending in a vertical direction, a front wheel 52 rotatably provided at a bottom portion of the front wheel frame 51 about a front wheel axle 53, an upper portion of the front wheel frame 51 being rotatably connected to the frame; the rear wheel assembly 6 includes a rear wheel frame 61 extending in the up-down direction, a rear wheel 62 rotatably provided at the bottom of the rear wheel frame 61 about a rear wheel axle 63, and an upper portion of the rear wheel frame 61 is rotatably connected to the vehicle frame. Here, the front wheel assembly 5 and the rear wheel assembly 6 each have two groups respectively provided on the left and right sides.

The frame comprises two groups of side frames which are respectively arranged on the front side and the back side and extend along the up-down direction, namely a first side frame 1 positioned on the front side and a second side frame 2 positioned on the back side, an upper frame 4 rotationally arranged between the upper part of the first side frame 1 and the upper part of the second side frame 2, and a lower frame 3 rotationally arranged between the lower part of the first side frame 1 and the lower part of the second side frame 2. The frame also comprises a towing bar 9, and the towing bar 9 is rotatably connected to the upper part of the first side surrounding frame 1. When the trailer frame is in a unfolded state, a riding space for children to ride is formed by surrounding the first side wall frame 1, the second side wall frame 2, the upper surrounding frame 4 and the lower surrounding frame 3, wherein the lower surrounding frame 3 provides bearing support.

The first side frame 1 and the second side frame 2 are fixed frame frames, and in this embodiment, the first side frame and the second side frame are not foldable in the left-right direction; the lower surrounding frame 3 and the upper surrounding frame 4 extend along the front-rear direction and can be respectively folded along the front-rear direction, the front wheel assembly 5 and the rear wheel assembly 6 are mounted at the bottom of the lower surrounding frame 3, and the lower surrounding frame 3 is linked through a linkage mechanism when being folded along the front-rear direction, so that the front wheel assembly 5 and the rear wheel assembly 6 are overturned, and further are folded relatively to the frame. Specifically, the lower surrounding frame 3 includes a first lower frame 31 and a second lower frame 32 which can be folded relatively rotatably, the front part of the first lower frame 31 is rotatably connected with the first side surrounding frame 1, the rear part of the second lower frame 32 is rotatably connected with the second side surrounding frame 2, the rear part of the first lower frame 31 is rotatably connected with the front part of the second lower frame 32, here, the lower surrounding frame 3 further includes a lower connecting piece 33 for connecting the rear part of the first lower frame 31 with the front part of the second lower frame 32, and in the unfolded state, the first lower frame 31, the lower connecting piece 33 and the second lower frame 32 are sequentially connected from front to back and extend along the same length direction.

In this embodiment, referring to fig. 1, the first lower frame 31 includes two first lower surrounding rods 311 respectively disposed at the left and right sides and extending in the front-rear direction, and a first lower cross rod 312 fixedly disposed between the two first lower surrounding rods 311 and extending in the left and right direction; the second lower frame 32 includes two second lower surrounding rods 321 respectively disposed on the left and right sides and extending in the front-rear direction, and a second lower cross rod 322 fixedly disposed between the two second lower surrounding rods 321 and extending in the left-right direction, the lower connecting member 33 includes two groups of first lower surrounding rods 311 and second lower surrounding rods 321 respectively disposed on the left and right sides and respectively used for rotationally connecting the sides, specifically, on each of the left and right sides of the lower surrounding frame 3, the rear portion of the first lower surrounding rod 311 is rotationally connected to the front end portion of the lower connecting member 33 about a first shaft 34, the front portion of the second lower surrounding rod 321 is rotationally connected to the rear end portion of the lower connecting member 33 about a second shaft 35, the axes of the first shaft 34 and the second shaft 35 are all disposed in parallel to each other and extend in the left-right direction, and the first shaft 34 is located on the front side of the second shaft 35. The lower connecting piece 33 is further provided with a limiting structure for limiting the downward rotation positions of the first lower surrounding rod 311 and the second lower surrounding rod 321, so that the first lower frame 31 and the second lower frame 32 can stably provide bearing support after being unfolded along the front-rear direction.

The upper surrounding frame 4 comprises a first upper frame 41 and a second upper frame 42 which can be folded relatively, the front part of the first upper frame 41 is rotationally connected with the first side surrounding frame 1, the rear part of the second upper frame 42 is rotationally connected with the second side surrounding frame 2, the rear part of the first upper frame 41 is rotationally connected with the front part of the second upper frame 42, here, the upper surrounding frame 4 also comprises an upper connecting piece 43 for connecting the rear part of the first upper frame 41 and the front part of the second upper frame 42, and in the unfolded state, the first upper frame 41, the upper connecting piece 43 and the second upper frame 42 are sequentially connected from front to back and extend along the same length direction.

In this embodiment, as shown in fig. 1, the first upper frame 41 includes two first upper surrounding rods 411 that are disposed on both sides and extend in the front-rear direction; the second upper frame 42 includes two second upper surrounding rods 421 respectively disposed on the left and right sides and extending in the front-rear direction, the upper connecting member 43 has two groups respectively disposed on the left and right sides for rotationally connecting the first upper surrounding rod 411 and the second upper surrounding rod 421 on the left and right sides of the side, specifically, on each of the left and right sides of the upper surrounding frame 4, the rear portion of the first upper surrounding rod 411 is rotationally connected to the front end portion of the upper connecting member 43 around the third shaft 44, the front portion of the second upper surrounding rod 421 is rotationally connected to the rear end portion of the upper connecting member 43 around the fourth shaft 45, the axial leads of the third shaft 44 and the fourth shaft 45 are respectively disposed in parallel with each other and extend in the left and right direction, and the third shaft 44 is disposed on the front side of the fourth shaft 45. The upper connector 43 is further provided with a limiting structure for limiting the upward rotation positions of the first upper rail 411 and the second upper rail 421, so that the first upper frame 41 and the second upper frame 42 can stably extend in the front-rear direction after being unfolded in the front-rear direction.

Referring to the drawings, two sets of front wheel assemblies 5 are respectively provided at left and right sides of a bottom front portion of the first lower frame 31, specifically, on left and right sides of the frame, upper portions of front wheel frames 51 of the front wheel assemblies 5 are rotatably connected to the first lower surrounding bar 311 around an axis of the first lower surrounding bar 311; the two sets of rear wheel assemblies 6 are respectively disposed on left and right sides of the bottom rear portion of the second lower frame 32, specifically, on left and right sides of the frame, an upper portion of the rear wheel frame 61 of the rear wheel assembly 6 is rotatably connected to the second lower rail 321 around an axis of the second lower rail 321, and in the unfolded state of the trailer frame, both the axis of the first lower rail 311 and the axis of the second lower rail 321 extend in the front-rear direction.

The four linkage rods of the linkage mechanism comprise two front linkage rods 7 respectively used for linking the two groups of front wheel assemblies 5 and two rear linkage rods 8 respectively used for linking the two groups of rear wheel assemblies 6. The front linkage rod 7 is disposed between the first side frame 1 and the front wheel assembly 5, two ends of the front linkage rod 7 are respectively provided with a front connector 7a, the two ends of the front linkage rod 7 are respectively rotatably connected with the first side frame 1 and the front wheel frame 51 through the front connectors 7a, specifically, as shown in fig. 2, the front part of the first lower surrounding rod 311 of the first lower frame 31 is connected with the first side frame 1 at a point a, one end of the front linkage rod 7 is connected with the first side frame 1 at a point B through the front connectors 7a in a universal rotation manner, the other end of the front linkage rod 7 is connected with the front wheel frame 51 at a point C through the front connectors 7a in a universal rotation manner, the point a is located above the point C in an unfolding state, and the point B is located at the inner side of the point C in the left-right direction. The rear linkage rod 8 is arranged between the second side frame 2 and the rear wheel assembly 6, both ends of the rear linkage rod 8 are respectively provided with a rear connector 8a, and both ends of the rear linkage rod 8 are respectively rotatably connected with the second side frame 2 and the rear wheel frame 61 through the rear connectors 8 a. In this embodiment, the front connector 7a and the rear connector 8a are spherical connectors, however, in other embodiments, the front connector 7a and the rear connector 8a may be other connectors capable of realizing universal rotation connection.

Referring to fig. 1 and 2, in the unfolded state of the child trailer, the upper surrounding frame 4 and the lower surrounding frame 3 are unfolded along the front-rear direction respectively, the two sets of front wheel assemblies 5 and the two sets of rear wheel assemblies 6 are supported at the bottom of the frame respectively, the front wheel frame 51 and the rear wheel frame 61 extend along the up-down direction respectively, and the towing bar 9 extends obliquely from back to front upwards for towing operation.

When the child trailer needs to be folded, referring to fig. 3 to 5, the towing bar 9 is turned down and folded on the front side of the first side surrounding frame 1, and then the lower connecting piece 33 is lifted up, so that the first lower frame 31 is turned up relative to the first side surrounding frame 1, the second lower frame 32 is turned up relative to the second side surrounding frame 2, the first lower frame 31 and the second lower frame 32 are converted to extend in the up-down direction, so that the lower surrounding frame 3 is gradually folded in the front-back direction, and meanwhile, the upper connecting piece 43 moves down, so that the first upper frame 41 and the second upper frame 42 are turned down relative to the first side surrounding frame 1 and the second side surrounding frame 2, respectively, so that the upper surrounding frame 4 is gradually folded in the front-back direction.

When the lower surrounding frame 3 is turned and folded, the front linkage rods 7 at the two sides are respectively linked to enable the front wheel assemblies 5 at the two sides to integrally turn inwards, the two groups of front wheel assemblies 5 are turned in the left-right direction in opposite directions to be gradually folded relative to the first lower frame 31, the rear linkage rods 8 at the two sides are respectively linked to enable the rear wheel assemblies 6 at the two sides to integrally turn inwards, and the two groups of rear wheel assemblies 6 are turned in the left-right direction in opposite directions to be gradually folded relative to the second lower frame 32. During the gradual transition of the first and second lower frames 31 and 32 to extend in the up-down direction, the front wheel assembly 5 and the rear wheel assembly 6 are also turned over accordingly, so that the front wheel frame 51 and the rear wheel frame 61 are gradually transitioned to extend in the front-rear direction.

Referring to fig. 6 to 8, in the folded state, the first upper frame 41, the first lower frame 31 and the first side frame 1 are folded, the second upper frame 42, the second lower frame 32 and the second side frame 2 are folded, the lower connecting piece 33 and the upper connecting piece 43 extend along the front-rear direction, the lower connecting piece 33 is located above the upper connecting piece 43, and all the wheel assemblies, namely, the two front wheel assemblies 5 and the two rear wheel assemblies 6 are turned over and folded in the space formed by the upper surrounding frame 4, the lower surrounding frame 3, the first side frame 1 and the second side frame 2, in particular, the space is located between the first lower frame 31 and the second lower frame 32 along the front-rear direction. The axis of the first lower surrounding rod 311 and the axis of the second lower surrounding rod 321 are both converted to extend along the up-down direction, the two groups of front wheel assemblies 5 are arranged side by side along the left-right direction, the two groups of rear wheel assemblies 6 are arranged side by side along the left-right direction, the front wheel axle 53 and the rear wheel axle 63 both extend along the front-rear direction, and the front wheel assemblies 5 and the rear wheel assemblies 6 on the same side on the frame are arranged in an overlapping manner along the front-rear direction. The whole body of the folded child trailer is regular square, and all wheel assemblies are contained in the inner space formed by folding each rod piece of the frame, so that the whole height is greatly reduced, the whole size of the folded child trailer is greatly reduced, and convenience is brought to daily containing and carrying of users.

The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and to implement the same, but are not intended to limit the scope of the present invention, and all equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of the present invention.

Claims

1. A child trailer having an unfolded state and a folded state, the child trailer comprising a frame, a plurality of sets of wheel assemblies disposed at a bottom of the frame, characterized in that: the frame is including locating the front and back both sides and all along two sets of side wall frames that extend in the upper and lower direction, rotationally set up two sets of on the side wall frame upper portion enclose the frame, and rotationally set up two sets of down enclosing the frame between the side wall frame lower part, go up enclosing the frame with down enclosing the frame and respectively extend in the front and back direction and respectively can fold up the ground along the front and back direction setting, every group the wheel subassembly all includes the wheel carrier and sets up around the wheel axle rotationally the wheel body of wheel carrier bottom, the wheel carrier rotationally connect in on the lower enclosing the frame, the frame with be provided with between the wheel body and be used for the linkage wheel subassembly upset the link gear, the link gear includes the gangbar at least, one end of gangbar with side wall frame universal rotationally is connected, another end of gangbar with the wheel carrier universal rotationally is connected, the in-back direction is in-out state conversion's the process of children's trailer, down enclosing the wheel carrier is in the front and back direction setting up the wheel carrier is relative the wheel carrier is in the direction is folded up down along the direction.

2. A child trailer according to claim 1, wherein: the wheel axle extends along the left-right direction when the child trailer is in a unfolded state; when the child trailer is in a folded condition, the axle extends in a fore-aft direction.

3. A child trailer according to claim 1, wherein: the multiunit wheel components is including locating two sets of front wheel components of frame bottom front portion left and right sides, locate two sets of rear wheel components of frame bottom rear portion left and right sides, works as children's trailer is in under the folded condition, two sets of front wheel components are arranged side by side along left and right directions, two sets of rear wheel components are arranged side by side along left and right directions, be located on the same side on the frame the front wheel components with rear wheel components is arranged along fore-and-aft direction overlapping.

4. A child trailer according to claim 1, wherein: the two ends of the linkage rod in the length direction are respectively provided with a connector, and the two ends of the linkage rod are respectively connected with the wheel frame and the frame in a universal rotation manner through the connectors, wherein the connectors are spherical joint pieces.

5. A child trailer according to claim 1, wherein: the wheel frame is rotationally connected with the frame around a rotation center line, and the rotation center line extends along the front-back direction when the child trailer is in a unfolded state; the child trailer is in a folded condition, with the centre line of rotation extending from top to bottom.

6. A child trailer according to any one of claims 1 to 5, wherein: the lower surrounding frame comprises a first lower frame and a second lower frame which can be folded in a relative rotating manner, the rear part of the first lower frame is connected with the front part of the second lower frame in a relative rotating manner, a plurality of groups of wheel assemblies comprise two groups of front wheel assemblies arranged on the left side and the right side of the front part of the first lower frame, two groups of rear wheel assemblies arranged on the left side and the right side of the rear part of the second lower frame, the two groups of front wheel assemblies are turned over in the opposite direction and folded in the process of converting an unfolding state into a folding state, the two groups of rear wheel assemblies are turned over in the opposite direction, and the lower surrounding frame is folded in the front-rear direction so that the front wheel assemblies and the rear wheel assemblies are folded in the front-rear direction between the first lower frame and the second lower frame.

7. A child trailer according to claim 6, wherein: the first lower frame is including locating left and right sides and two first lower enclosing pole that all extend along the fore-and-aft direction respectively, the second lower frame is including locating left and right sides and two second lower enclosing poles that all extend along the left and right direction respectively, the wheel carrier of front wheel subassembly can be around first enclosing pole's axial lead rotationally locates on the first enclosing pole, the wheel carrier of rear wheel subassembly can be around second enclosing pole's axial lead rotationally locates on the second lower enclosing pole.

8. The child trailer of claim 7, wherein: the frame is left and right sides, the lower frame still includes down the connecting piece, the rear portion of first lower enclosing the pole around first axle rotationally connect in down on the connecting piece, the second lower front portion of enclosing the pole around the second axle rotationally connect in down on the connecting piece, first axle with the second axle all extends along left and right directions and sets up parallel to each other, still be equipped with on the connecting piece and be used for right first lower enclosing the pole with second lower enclosing the pole and rotate down the limit structure that the position was spacing down.

9. A child trailer according to claim 6, wherein: a group of linkage rods are rotatably arranged between the wheel frame of each front wheel assembly and the side frame on the front side; a group of linkage rods are rotatably arranged between the wheel frame of each rear wheel assembly and the side frame at the rear side.

10. A child trailer according to claim 1, wherein: the child trailer is in a folded state, the first upper frame, the first lower frame and the side frames on the front side are mutually folded, the second upper frame, the second lower frame and the side frames on the rear side are mutually folded, the lower connecting piece is located above the upper connecting piece, and all wheel assemblies are overturned and folded to form a space inside by surrounding the upper frame, the lower frame and the two groups of side frames.