CN103407478B - Folding trailer - Google Patents

Abstract

The invention discloses a folding trailer which comprises a front frame assembly, a rear frame assembly and a connecting mechanism for connecting the front frame assembly and the rear frame assembly; the rear frame assembly comprises a rear luggage carrier, two rear wheel assemblies, a rear baffle arranged at the rear end of the rear luggage carrier and two connecting pieces used for connecting the rear baffle and the rear luggage carrier; the front end of the connecting piece is provided with a first pin joint hole, a rear furling abutting surface, a rear unfolding abutting surface and a rear arc-shaped transition surface; the rear furling abutting surface is positioned above the rear unfolding abutting surface and is vertical to the rear furling abutting surface; the distance between the central axis of the first pivot hole and the rear unfolding abutting surface is greater than the distance between the central axis and the rear folding abutting surface; the rear end of the connecting piece is provided with a second pivot hole, a furled bearing surface and an unfolded bearing surface, the furled bearing surface and the unfolded bearing surface are positioned below the second pivot hole, and the unfolded bearing surface is positioned on one side of the second pivot hole close to the first pivot hole. The invention has reasonable and compact structure.

Description

collapsible trailer

technical field

The invention relates to the technical field of trailers, in particular to a foldable trailer.

Background technique

People often use four-wheel trailers when shopping and carrying items, which can save energy for users. However, four-wheel trailers are generally large in size at present, cannot be folded and folded, are inconvenient to carry, and take up a lot of space when stored.

Patent document CN202186404U discloses a foldable luggage cart, which includes a telescopic frame, the lower part of which is provided with a cylindrical push-pull rod hinged to the load-carrying bottom plate of the luggage cart, and the upper part of the cylindrical push-pull rod is provided with a first annular groove , the lower end surface of the first annular groove is provided with a first helical guide surface; the load-bearing bottom plate is folded and attached to the frame, and it is arranged perpendicular to the frame after unfolding for carrying luggage; the side of the load-bearing bottom plate connected to the frame is provided with The wheel vertical stroke control part fixedly connected with the bearing base plate; the wheel bracket has a second annular groove adapted to fit with the cylindrical push-pull rod, and the upper end surface of the second annular groove is provided with the first spiral guide. The second spiral guide surface matched with the guide surface, a rotating torsion spring is fixed and seated in the second annular groove; the push-pull rod is vertically installed in the second annular groove, and the shaft hole at the lower part of the push-pull rod is socketed in the vertical stroke of the wheel In the shaft of the control part; when the bearing base plate is unfolded, the wheel vertically forms the control part to push the second annular groove, and is guided under the joint action of the first helical guide surface and the second helical guide surface The wheel moves up vertically and rotates outward on both sides. When the load-bearing base plate is folded, the wheel rotates back under the action of the torsion spring and moves vertically downward; the wheel edge of the folded wheel protrudes from the folded load-bearing Bottom edge of base plate.

This patent document describes in detail the mechanism and working principle of the foldable wheels. However, this kind of foldable luggage cart cannot be widely used in factory workshops because it is a push-pull cart with only two wheels and has a small load-carrying force.

Contents of the invention

The purpose of the present invention is to provide a foldable trailer with reasonable and compact structure and comprehensive functions.

The technical solution for realizing the purpose of the present invention is: a collapsible trailer, including a front frame assembly, a rear frame assembly and a coupling mechanism for connecting the front frame assembly and the rear frame assembly; the rear frame assembly includes a rear load frame, two rear wheel assemblies, a tailgate arranged at the rear end of the rear carrier, and two connectors for connecting the tailgate and the rear carrier; There is a rearwardly protruding rear sliding column, and each rear sliding column is provided with an annular rear limit block, and the rear end of each rear limit block is provided with a plurality of rear limit tooth grooves; the rear end of each rear sliding column A rear pin hole is provided; the front end of each connector is provided with a first pivot hole, a rear folded abutment surface, a rear unfolded abutment surface, and a rear arc-shaped transition surface connecting the rear folded abutment surface and the rear unfolded abutment surface ; each connecting piece is connected to a corresponding rear sliding column through a pin shaft passing through the first pivot hole and the rear pin hole, and the distance between the central axis of the first pivot hole and the rear abutment surface is greater than the distance between the central axis and the rear The distance between the folded abutment surfaces; each rear unfolded abutment surface is parallel to the plane where the tailgate is located, and each rear folded abutment surface is perpendicular to the plane where the rear baffle is located; the rear end of each connector is provided with a The second pivot hole, the folded force-bearing surface, and the unfolded force-bearing surface, the folded force-bearing surface is located on the side of the second pivot hole away from the first pivot hole, and the expanded force-bearing surface is located near the second pivot hole. One side of a pivot hole; each rear wheel assembly includes a rear wheel frame with a rear sleeve, a rear torsion spring and a rear wheel that is rotatably arranged on the rear wheel frame; the front end of each rear sleeve is provided with each rear limit The rear limiting protruding teeth matched with the tooth grooves; the rear casing is set on the corresponding rear sliding column, and the rear torsion spring is sleeved on the corresponding rear sliding column and is located in the rear casing; the rear baffle is provided with Two rear connecting bosses, each rear connecting boss is provided with a rear axle hole and a force-bearing convex plate protruding outward along the lateral direction of the rear carrier; each rear connecting boss and a corresponding connecting piece pass through the rear axle hole and The pin shaft of the second pivot hole is rotatably connected; when the load-bearing convex plate rotates around the second pivot hole with the rear connecting boss, it can abut against the folded force-bearing surface and the unfolded force-bearing surface of the connector , and then drive the connecting piece to rotate.

The structure of the present invention is more reasonable and compact, and the function is more comprehensive. It can realize the stacking and flattening of the tailgate and the rear load frame, and can also carry out secondary positioning of the rear wheel assembly, so as to realize the stable rolling of the rear wheel and the alignment with the rear load. Stacking of racks.

Description of drawings

Fig. 1 is a kind of three-dimensional structure schematic diagram of the present invention;

Fig. 2 is a schematic diagram of a three-dimensional structure of the connector shown in Fig. 1 viewed from another angle;

Fig. 3 is a schematic diagram of a three-dimensional structure of the four-wheel foldable trailer made of the connector shown in Fig. 1 when it is in an unfolded state;

Fig. 4 is a schematic diagram of a three-dimensional structure of the front frame assembly in the trailer shown in Fig. 3;

Fig. 5 is a side view of the front frame assembly shown in Fig. 4;

Fig. 5 is a side view of the front baffle in the front frame assembly shown in Fig. 4;

Figure 6 is an exploded view of the front frame assembly shown in Figure 4;

Figure 7 is an exploded view of the front frame assembly shown in Figure 3;

Fig. 8 is a schematic diagram of a three-dimensional structure of the rear frame assembly in the trailer shown in Fig. 3;

Fig. 9 is a perspective view of the rear frame assembly shown in Fig. 8 viewed from another angle;

Figure 10 is a side view of the rear frame assembly shown in Figure 8;

Figure 11 is an exploded view of the rear frame assembly shown in Figure 8;

Figure 12 is an exploded view of the rear frame assembly shown in Figure 9;

Fig. 13 is a schematic diagram of a three-dimensional structure of the trailer shown in Fig. 3 when it is in a flattened state;

Fig. 14 is a schematic diagram of a three-dimensional structure of the tailgate in the trailer shown in Fig. 13;

Fig. 15 is a schematic diagram of a three-dimensional structure of the trailer shown in Fig. 3 when it is in a preliminary folded state;

Figure 16 is an exploded view of the tailgate and connectors in Figure 15;

Figure 17 is a side view of the trailer shown in Figure 15;

Fig. 18 is a schematic structural view of the coupling mechanism in the trailer shown in Fig. 3;

Fig. 19 is a schematic perspective view of the trailer shown in Fig. 3 when it is in a fully folded state;

Figure 20 is a side view of the trailer shown in Figure 19 .

The marks shown in the accompanying drawings are: front frame assembly 1, front load rack 11, front strut 111, front limit stand 112, front limit tooth groove 113, front pin hole 114, front wheel assembly 12, front cover Pipe 121, front wheel frame 122, front torsion spring 123, front wheel 124, front limit protruding teeth 125, front baffle plate 13, front connecting boss 131, front axle hole 132, front retracting abutment surface 133, front unfolding abutment Connecting surface 134, front arc-shaped transition surface 135, rotating connection part 136, clamping plate 137, tie rod 14, rear frame assembly 2, rear loading rack 21, rear sliding column 211, rear limit block 212, rear limit Tooth groove 213, rear pin hole 214, rear wheel assembly 22, rear bushing 221, rear wheel frame 222, rear torsion spring 223, rear wheel 224, rear limiting protruding tooth 225, rear baffle plate 23, rear connecting boss 231 , the rear shaft hole 232, the load-bearing convex plate 233, the connector 24, the first pivot hole 241, the rear abutment surface 242, the rear expansion abutment surface 243, the rear arc transition surface 244, the second pivot hole 245 , retract bearing surface 246, expand bearing surface 247, coupling mechanism 3, front coupling rod 31, positioning wheel 32, positioning notch 321, rear coupling rod 33, coupling convex plate 34, shaft rod 35, ring block 36, screw thread Spring 37, connecting bolt assembly 38, pin shaft 100.

detailed description

(Example 1)

This embodiment is a connecting piece for a foldable trailer, as shown in Figure 1 and Figure 2, the front end of the connecting piece 24 is provided with a first pivot hole 241, a rear folded abutment surface 242, and a rear unfolded abutment surface 243, and the rear arc-shaped transition surface 244 connecting the folded abutment surface and the rear unfolded abutment surface; the rear folded abutment surface is located on the rear expanded abutment surface and is perpendicular to the rear folded abutment surface; the first pivot hole The distance between the central axis of the center axis and the rear expanded abutment surface is greater than the distance between the central axis and the rear folded abutment surface; the rear end of the connector is provided with a second pivot hole 245, a folded bearing surface 246, and an expanded bearing surface 247 , the folded force bearing surface and the expanded force bearing surface are located below the second pivot hole, and the folded force bearing surface is located on the side of the second pivot hole away from the first pivot hole, and the expanded force bearing surface is located at the second pivot hole Close to the side of the first pivot hole.

(Application example 1)

This application example is a four-wheel folding trailer made by the above-mentioned embodiment 1, as shown in Fig. 3 to Fig. 20, including a front frame assembly 1, a rear frame assembly 2 and a The coupling mechanism of the rack assembly 3.

The specific structure of this application example when it is in the unfolded state is shown in Figures 3 to 12. The front frame assembly includes a front load frame 11, two front wheel assemblies 12, and a front baffle plate 13 arranged at the front end of the front load frame. , and the pull rod 14 arranged on the front baffle; the left and right sides of the front end of the front load rack are respectively provided with a front sliding column 111 protruding forward, and each front sliding column is provided with an annular front limit block 112, The front end of each front limit stand is provided with a plurality of front limit tooth slots 113; the front end of each front strut is provided with a front pin hole 114; Spring 123 and the front wheel 124 that rotation is arranged on the front wheel frame; The rear end of each front sleeve pipe is provided with the front limit salient tooth 125 that cooperates with each front limit tooth groove; Front sleeve sleeve is set on a corresponding front On the sliding column, the front torsion spring is sleeved on the corresponding front sliding column, and is located in the front casing; the front baffle is provided with two front connecting bosses 131, and each front connecting boss is provided with a front axle hole 132. The front gathering abutment surface 133, the front unfolding abutment surface 134, and the front arc-shaped transition surface 135 connecting the front gathering abutment surface and the front unfolding abutment surface; as shown in Fig. 6, the central axis of the front axle hole and The distance a of the front unfolded abutment surface is greater than the distance b between the central axis and the front folded abutment surface; each front connecting boss is rotatably connected to the front strut through a pin shaft 100 passing through the front shaft hole and a corresponding front pin hole; Each front unfolding abutting surface is parallel to the plane where the front baffle is located, and each folded abutting surface is perpendicular to the plane where the front baffle is located.

The rear frame assembly includes a rear carrier 21 , two rear wheel assemblies 22 , a tailgate 23 arranged at the rear end of the rear carrier, and two connectors 24 for connecting the rear carrier and the rear carrier.

The left and right side ends of the rear end of the rear carrier are respectively provided with a rearwardly protruding rear sliding column 211, each rear sliding column is provided with an annular rear limit stop platform 212, and the rear end of each rear limit stop platform is provided with multiple A rear limit tooth groove 213; the rear end of each rear sliding column is provided with a rear pin hole 214; the front end of each connector is provided with a first pivot hole 241, a rearwardly folded abutment surface 242, a rearwardly unfolded abutment surface 243, And the rear arc-shaped transition surface 244 that connects the abutment surface after being folded and the abutment surface after deployment; each connecting piece is connected with a corresponding rear sliding column through the pin shaft 100 passing through the first pivot hole and the rear pin hole 214, The distance between the central axis of the first pivot hole and the rear unfolded abutment surface is greater than the distance between the central axis and the rear stowed abutment surface; each rear unfolded abutment surface is parallel to the plane where the tailgate is located, and each rear stowed abutment surface is vertical On the plane where the rear baffle is located; the rear end of each connector is provided with a second pivot hole 245 for rotating connection with the rear baffle, a folded force-bearing surface 246, and an expanded force-bearing surface 247, and the folded force-bearing surface is located at the second The pivot hole is far away from the side of the first pivot hole, and the expanded load-bearing surface is located at the side of the second pivot hole close to the first pivot hole; each rear wheel assembly includes a rear wheel frame 222 with a rear sleeve 221, a rear Torsion spring 223 and the rear wheel 224 that rotation is arranged on the rear wheel frame; The front end of each rear sleeve pipe is provided with the rear position-limiting protruding tooth 225 that cooperates with each rear position-limiting tooth groove; On the sliding column, the rear torsion spring is sleeved on the corresponding rear sliding column, and is located in the rear casing; the rear baffle is provided with two rear connecting bosses 231, and each rear connecting boss is provided with a rear axle hole 232 And the load-bearing convex plate 233 that protrudes outward along the lateral direction of the rear object rack; each rear connecting boss and a corresponding connecting member are rotatably connected by the pin shaft 100 passing through the rear axle hole and the second pivot hole; the load-bearing convex plate is in the As the rear connecting boss rotates around the second pivot hole, it can abut against the retracted force-bearing surface and the unfolded force-bearing surface of the connecting piece, thereby driving the connecting piece to rotate.

As shown in Figure 18, the coupling mechanism 3 in this application example includes two front coupling rods 31 arranged on the left and right sides of the rear end of the front carrier, positioning wheels 32 fixedly arranged on each front coupling rod, Two rear connecting rods 33 at the left and right sides of the front end of the object rack, a connecting convex plate 34 fixedly arranged on each rear connecting rod, a shaft rod 35 which runs through the two rear connecting rods and can move back and forth along the left and right directions, and is fixedly arranged on the shaft Two annular stops 36 on the rod, threaded springs 37 for providing return elastic force for the axle rods, and connecting bolt assemblies 38 for rotationally connecting each rear coupling rod and a corresponding positioning wheel; There are two arc-shaped positioning gaps 321 symmetrical to the center, and each annular block is inserted into or moved out of a corresponding positioning gap during the reciprocating movement of the shaft; the front frame assembly and the rear frame assembly can be After turning 180 degrees around the connecting bolt assembly 38, they are stacked.

In this application example, the end of the front baffle close to the front connecting boss is provided with a rotating connection portion 136 with a pin hole, and the end of the front baffle far away from the front connecting boss is provided with two protruding clamping plates 137; The rotating connection part of the front baffle is connected in rotation, and the middle part of the pull rod can be clamped and connected between the two clamping plates. In practice, the pull rod can also be fixedly arranged on the front baffle.

When this application example is in the unfolded state, as shown in Figure 3 to Figure 12, the upper surfaces of the front carrier and the rear carrier are on the same plane, and the front carrier and the rear carrier are connected by a coupling mechanism and positioned by The wheels are embedded in the positioning gaps of the corresponding positioning wheels to lock the two. At this time, in the front frame assembly, the front baffle is perpendicular to the front load rack, and the front abutment surface 131 on the front limit stop is parallel to the plane where the front baffle is located, and abuts against the front end of the front sleeve 121 On the surface, at the same time, each front limiting protruding tooth at the rear end of the front casing is embedded in the corresponding front limiting tooth groove, and the front limiting tooth groove has the effect of restricting the rotation of the front casing, so that the front wheel at this time Perpendicular to the plane where the front load rack is located, it can be rolled to achieve normal dragging. In the rear frame assembly, the tailgate is perpendicular to the plane where the rear cargo rack is located, and the load-bearing convex plate 233 of the rear connecting boss abuts on the folded force-bearing surface 246 of the connector, and the folded force-bearing surface is in this state Next, the rear baffle can be prevented from continuing to rotate forward; the rear expansion abutment surface 243 in each connecting piece is parallel to the plane where the rear baffle is located, and abuts against the rear end surface of the corresponding rear sleeve, so that the front end of the rear sleeve Each of the rear limiting protruding teeth is embedded in the rear limiting tooth groove, and the rear limiting tooth groove has the effect of restricting the rotation of the rear bushing, so that the rear wheel is perpendicular to the plane where the rear load rack is located, and can roll to Realize normal dragging.

The specific structure of this application example in the flattened state is shown in Figures 13 to 14. In the unfolded state shown in Figure 3, the external force pushes the rear baffle to rotate backward around the rear axle hole until the load-bearing convex plate 233 abuts on the On the unfolded load-bearing surface 247 of the connector, the upper surface of the tailgate and the upper surface of the rear carrier are in the same plane at this time, and under the limiting action of the unfolded load-bearing surface 247 of the connector, the tailgate can be prevented from continuing to Rotate backwards; this structure can use the tailgate as a load board, effectively increasing the load-bearing area of the trailer.

The specific structure of this application example in the preliminary folded state is shown in Fig. 15 to Fig. 17. In the unfolded state shown in Fig. 3, the external force pushes the rear baffle forward. The connecting piece is folded on the load-bearing surface 246, thereby driving the connecting piece to rotate forward around the first pivot hole 241 until the rear gathering abutment surface 242 is perpendicular to the plane where the rear carrier is located and abuts against the rear end surface of the rear casing Since the distance between the central axis of the first pivot hole and the rear unfolded abutment surface is greater than the distance between the central axis and the rear folded abutment surface, the rear sleeve will be held by the rear torsion spring 223 during the rotation of the connector. Under the action of the elastic force, it slides backward for a certain distance, so that the rear limit teeth move out from the corresponding rear limit tooth grooves. Since the rear limit tooth grooves no longer have the effect of restricting the rotation of the rear casing, the rear casing Under the action of the torsion force of the rear torsion spring, the rear wheel frame 222 and the rear wheel 224 are driven to rotate at a certain angle and then abut against the bottom surface of the rear carrier. In addition, in the unfolded state shown in FIG. 3 , the external force pushes the front baffle backward, and drives the front connecting boss 131 to rotate backward around the front shaft hole 132 until the front folded abutment surface 133 abuts against the front end surface of the front casing. Since the distance a between the central axis of the front axle hole and the front unfolded abutment surface is greater than the distance b between the central axis and the front folded abutment surface, the front bushing will move forward during the rearward rotation of the tailgate. Slip a certain distance, so that the front limit teeth move out from the corresponding front limit tooth grooves, because the front limit tooth grooves no longer have the effect of restricting the rotation of the front bushing, so the front bushing will be under the torsion of the front torsion spring Next, drive the front wheel frame and the front wheel to rotate at a certain angle to abut against the bottom surface of the front carrier.

The specific structure of this application example in the fully folded state is shown in Figures 19 to 20. In the preliminary folded state shown in Figure 15, the shaft 35 is pressed, so that the shaft overcomes the return elastic force of the threaded spring 37 and moves a certain distance, so that The annular stop fixed on the shaft moves out from a corresponding positioning notch 321, so that the carrier and the rear carrier can be folded, and when the front carrier or the rear carrier is turned 180 degrees to make the two superimposed , that is, after the bottom surface of the front frame assembly is adjacent to the bottom surface of the rear frame assembly, the shaft rod is released, and the shaft rod moves and resets under the reset elastic force of the threaded spring 37, so that the annular stopper is embedded in the corresponding other In a positioning notch 321, the front carrier and the rear carrier are locked so that the two will not be separated by themselves.

In addition, this application example also has a feature, that is, when the connecting bolt assembly 38 is removed, the front frame assembly and the rear frame assembly can independently become a two-wheel folding trailer; Towing the holding bar, the front carrier continues to be the carrier; but for the rear frame assembly, the axle in the rear frame assembly is used as the towing holding bar, and the tailgate is used as the loading plate.

Apparently, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, rather than limiting the implementation of the present invention. For those of ordinary skill in the art, on the basis of the above description, other changes or changes in different forms can also be made. It is not necessary and impossible to exhaustively list all the implementation manners here. And these obvious changes or modifications derived from the spirit of the present invention are still within the protection scope of the present invention.

Claims (1)

1. a kind of folding trailer, including front frame component, Rear frame component and the coupling mechanism for coupling front frame component and Rear frame component；Rear frame component includes rear luggage carrier, two rear wheel assemblies, is arranged on the backboard of rear luggage carrier rear end and two connectors for connecting backboard and rear luggage carrier；It is characterized in that：The left and right sides end of luggage carrier rear end is respectively provided with a rearwardly projecting rear traveller afterwards, and each rear traveller is provided with multiple rear spacing teeth groove provided with limiting block platform after annular, the rear end of each rear limiting block platform；The rear end of each rear traveller is provided with rear pin-and-hole；Draw the rear arc transition face for drawing bearing surface and rear expansion bearing surface after bearing surface, afterwards expansion bearing surface and connection in provided with the first pivoted hole, afterwards in the front end of each connector；Each connector is rotated by the bearing pin through the first pivoted hole and rear pin-and-hole with traveller after corresponding one and is connected, and the distance of the central axis of the first pivoted hole and rear expansion bearing surface is more than the central axis and the rear distance for drawing bearing surface in；Expansion bearing surface is parallel to plane where backboard after each, and each rear bearing surface that draws in is perpendicular to plane where backboard；The rear end of each connector, which is provided with, to be used to rotate the second pivoted hole being connected with backboard, draws load-carrying surface in and expansion load-carrying surface, draw load-carrying surface in and be located at side of second pivoted hole away from the first pivoted hole, expansion load-carrying surface is located at the second pivoted hole close to the side of the first pivoted hole；Each rear wheel assemblies include rear wheel frame, rear torsion spring and the rear wheel being rotatably arranged on rear wheel frame with rear sleeve；The front end of each rear sleeve is provided with the rear spacing double wedge being engaged with each rear spacing teeth groove；Rear sleeve is set in after corresponding one on traveller, and rear torsion spring is set on corresponding rear traveller, and within rear sleeve；Backboard, which is provided with after two, connects boss, and each rear connection boss is provided with rear axis hole and the load protrusive board along rear luggage carrier horizontal direction evagination；Connection boss and a corresponding connector are rotated by the bearing pin through rear axis hole and the second pivoted hole after each connects；Load protrusive board with it is rear connection boss around the second pivoted hole rotate during, can be connected to the gathering load-carrying surface of connector and expansion load-carrying surface on, and then with follower link rotate；External force promotes backboard to be rotated backward around rear axis hole, until load protrusive board (233) is connected in the expansion load-carrying surface (247) of connector, now backboard upper surface and the upper surface of rear luggage carrier are in same plane, under the position-limiting action of the expansion load-carrying surface (247) of connector, backboard is prevented to continue to rotate backward.