1. A traction device, comprising:

the closed ring-shaped traction device comprises a closed ring-shaped traction device, wherein at least one traction head used for being connected with a carrier is arranged on the closed ring-shaped traction device;

the annular track corresponds to the annular track of the traction device and is used for bearing the carrier and allowing the carrier to move on the annular track;

the two driving devices are respectively arranged at two preset positions of the pulling rod circular track, and each driving device is provided with a power head capable of driving the pulling rod and a pushing structure used for moving the power head;

when one of the driving devices tensions and drives the traction device to rotate, the other driving device is in a standby state; after the traction head passes through the driving device in the standby state, the pushing structure of the driving device in the standby state starts to push the power head to be close to the traction rod, tension and drive the traction rod, the pushing structure of the driving device in the working state pushes the power head to be gradually far away from the traction rod, and the traction head enters the standby state after reaching the position capable of avoiding the traction head, so that the traction head can realize the non-blocking rotation.

2. The traction device as recited in claim 1, wherein the powerhead has a first engagement structure that engages the traction cable, the powerhead driving the traction device in an engagement drive.

3. The towing attachment in accordance with claim 1 wherein the power head of each of the drive arrangements includes three setting positions: a working position, a transition position and a standby position;

the working position refers to a position where the power head can be independently tensioned and drive the traction head, and the traction head cannot pass through the working position;

the standby position refers to a position where the power head is separated from the traction object, and the traction head can pass through the standby position without obstruction;

the transition position is a preset interval of the power head between the working position and the standby position, and the traction head cannot pass through the transition position;

when one power head of the two driving devices is in a working position, the other power head is in a standby position; and the two driving devices realize the driving switching of the traction device at the transition position.

4. The towing attachment in accordance with claim 3 wherein the two drive devices effecting drive switching of the tow bar at the transition location comprises:

the driving device which is currently at a standby position moves towards the working position until the power head contacts the traction device; synchronously, the driving device at the working position gradually moves towards the standby position;

when the pulling force is kept within a preset threshold value range, the driving device starting from the standby position continuously moves towards the working position until the preset working position stops; the driving device starting from the working position continuously moves to the standby position until the standby position stops;

when the tension force of the traction device exceeds a preset threshold value, the driving device starting from the standby position stops moving to the working position of the driving device, and the driving device starting from the working position continues moving to the standby position; both said drives continue said predetermined movement until said tension of said traction means falls back to a predetermined threshold;

when the tension of the traction device is lower than a preset threshold value, the driving device starting from the standby position continues to move to the working position of the driving device, and the driving device starting from the working position stops moving to the standby position of the driving device; both of the drives continue the predetermined movement until the tension of the traction means falls back to a predetermined threshold.

5. The traction device as claimed in claim 3, wherein when the number of the traction heads is 2 or more than 2, the traction heads are distributed in the traction device in a manner that: before one of the traction heads passes through the drive in the standby state, no traction head is allowed to pass through the transition point of the drive in operation.

6. Traction device according to any one of claims 1 to 5, characterized in that two said drive means are provided at two opposite positions of the endless closed track, both drive means obtaining a balanced standby, working time.

7. Traction means according to any one of claims 1 to 5, characterized in that the two drive means are arranged concentrically within a defined distance which is at least able to accommodate the traction head.

8. The towing attachment in accordance with claim 2 wherein the powerhead includes a first drive motor, a gear box coupled to an output of the first drive motor, a bearing housing at one end of the gear box, and a first engagement structure at one end of the bearing housing for mating with the towing article.

9. The traction device as recited in claim 6, wherein the pusher mechanism includes:

the support frame is used for bearing the power head;

the lead screw is connected with the output end of the second driving motor, the lead screw nut is connected to the support frame, and the second driving motor and the lead screw are used for driving the support frame to move;

the guide rail is used for supporting and limiting a moving path of the support frame, the support frame can reciprocate along the guide rail in the direction perpendicular to the meshing surface of the traction object under the driving of the second driving motor and the lead screw, and the moving track of the power head covers a working position, a transition position and a standby position in each one-way stroke of the support frame;

the spring with preset tension force is connected between the second driving motor and the support frame, and when the lead screw rotates and pushes the support frame to move, the spring stretches;

a tension monitoring device for measuring the tension of the tractor;

and the controller is in communication connection with the tension monitoring device and the second driving motor, and controls the second driving motor to drive the power head to move on the guide rail according to the tension value acquired by the tension monitoring device so as to balance the tension of the traction object.

10. A traction device as claimed in claim 9, wherein there are also two idler wheels at a location corresponding to each said drive means; each idler wheel surface is provided with a second meshing structure capable of meshing with the meshing side of the tractor;

when the standby position is adopted, the first meshing structure of the power head is arranged on one side of the traction device, the two idle wheels are arranged on the other side of the traction device, and the traction head can pass through the traction device without obstruction;

when the power head moves from the standby position to the working position, the first meshing structure of the power head pulls the pulling rod to pass between the two idle wheels, the pulling rod forms a U-shaped turn between the first meshing structure and the two idle wheels, and the pulling rod has a preset wrap angle on the first meshing structure.

11. The towing attachment in accordance with claim 1 wherein the tow head comprises:

the connecting part is connected with the carrier and arranged between the carrier and the towing object;

and the traction part is used for connecting the traction rod with the connecting part.

12. Traction apparatus as claimed in claim 10 or 11, wherein the traction head is located centrally symmetrically with respect to the vehicle.

13. The traction device according to claim 6, wherein the two drive devices are arranged at two opposite positions of the annular closed track by the following structural forms:

a driving device is arranged on a mobile device which can carry the driving device to circularly switch at two positions of the circular track.

14. The traction device according to claim 6, wherein the two drive devices are arranged at two opposite positions of the annular closed track by the following structural forms:

and sharing the power head of one driving device with the power head of the other driving device by using the pushing structure, and pushing the two power heads to circularly switch at two positions of the annular track by using the pushing structure.

15. A logistics transport system, comprising a pulling device according to any one of claims 1 to 14.

Background

Along with the development of logistics and the improvement of automation degree, logistics transmission systems are more and more widely applied to various occasions. In many industries, such as production lines and assembly lines of electronics, machinery, medicine, chemical engineering and the like, steel wire ropes or other flexible materials are generally adopted for transmission. The traction system adopting the steel wire rope is generally characterized in that devices to be dragged are connected to two ends of the steel wire rope, and the positions of the end devices are changed by rotating the steel wire rope on a friction wheel or a winch, so that objects are dragged.

Generally, a device for towing by using a steel wire rope or other flexible materials cannot form a closed loop path for towing because when the steel wire rope is towed by using a friction wheel or a winch, the operation of the friction wheel or the winch can be prevented by the connection point of the steel wire rope and a vehicle. The flexible material traction transmission device has the advantage of low cost compared with other types of logistics transmission devices, so how to manufacture the traction device which can continuously circulate and has low production cost becomes an important direction for the research of technicians in the field.

Disclosure of Invention

An object of the embodiment of the application is to provide a traction device, which can meet the requirement of continuous cycle traction by utilizing flexible material traction, and has the characteristics of simple structure and low production cost.

Another object of the embodiments of the present application is to provide a logistics transportation system using the above traction apparatus.

In a first aspect, a traction device is provided, comprising:

the closed ring-shaped traction device comprises a closed ring-shaped traction device, wherein at least one traction head used for being connected with a carrier is arranged on the closed ring-shaped traction device;

the annular track corresponds to the annular track of the traction device and is used for bearing the carrier and allowing the carrier to move on the annular track;

the two driving devices are respectively arranged at two preset positions of the pulling rod circular track, and each driving device is provided with a power head capable of driving the pulling rod and a pushing structure used for moving the power head;

when one of the driving devices tensions and drives the traction device to rotate, the other driving device is in a standby state; after the traction head passes through the driving device in the standby state, the pushing structure of the driving device in the standby state starts to push the power head to be close to the traction rod, tension and drive the traction rod, the pushing structure of the driving device in the working state pushes the power head to be gradually far away from the traction rod, and the traction head enters the standby state after reaching the position capable of avoiding the traction head, so that the traction head can realize the non-blocking rotation.

In one embodiment, the powerhead has a first engagement structure that engages the pull cable, and the manner in which the powerhead drives the pull cable is an engagement drive.

In one embodiment, the powerhead of each of the drive means includes three setting positions: a working position, a transition position and a standby position;

the working position refers to a position where the power head can be independently tensioned and drive the traction head, and the traction head cannot pass through the working position;

the standby position refers to a position where the power head is separated from the traction object, and the traction head can pass through the standby position without obstruction;

the transition position is a preset interval of the power head between the working position and the standby position, and the traction head cannot pass through the transition position;

when one power head of the two driving devices is in a working position, the other power head is in a standby position; and the two driving devices realize the driving switching of the traction device at the transition position.

In one embodiment, the two driving devices effecting driving switching of the pulling device at the transition location comprises:

the driving device which is currently at a standby position moves towards the working position until the power head contacts the traction device; synchronously, the driving device at the working position gradually moves towards the standby position;

when the pulling force is kept within a preset threshold value range, the driving device starting from the standby position continuously moves towards the working position until the preset working position stops; the driving device starting from the working position continuously moves to the standby position until the standby position stops;

when the tension force of the traction device exceeds a preset threshold value, the driving device starting from the standby position stops moving to the working position of the driving device, and the driving device starting from the working position continues moving to the standby position; both said drives continue said predetermined movement until said tension of said traction means falls back to a predetermined threshold;

when the tension of the traction device is lower than a preset threshold value, the driving device starting from the standby position continues to move to the working position of the driving device, and the driving device starting from the working position stops moving to the standby position of the driving device; both of the drives continue the predetermined movement until the tension of the traction means falls back to a predetermined threshold.

In one embodiment, when the number of the pulling heads is 2 or more than 2, the pulling heads are distributed in the pulling head mode as follows: before one of the traction heads passes through the drive in the standby state, no traction head is allowed to pass through the transition point of the drive in operation.

In one embodiment, two driving devices are arranged at two opposite positions of the annular closed track, and the two driving devices obtain balanced standby and working time.

In one embodiment, two of the drive devices are arranged concentrically within a defined distance, which distance is at least capable of accommodating the traction head.

In one embodiment, the powerhead includes a first drive motor, a gear box coupled to an output of the first drive motor, a bearing housing at one end of the gear box, and a first engagement structure at one end of the bearing housing that mates with the tow object.

In one embodiment, the pusher jack mechanism comprises:

the support frame is used for bearing the power head;

the lead screw is connected with the output end of the second driving motor, the lead screw nut is connected to the support frame, and the second driving motor and the lead screw are used for driving the support frame to move;

the guide rail is used for supporting and limiting a moving path of the support frame, the support frame can reciprocate along the guide rail in the direction perpendicular to the meshing surface of the traction object under the driving of the second driving motor and the lead screw, and the moving track of the power head covers a working position, a transition position and a standby position in each one-way stroke of the support frame;

the spring with preset tension force is connected between the second driving motor and the support frame, and when the lead screw rotates and pushes the support frame to move, the spring stretches;

a tension monitoring device for measuring the tension of the tractor;

and the controller is in communication connection with the tension monitoring device and the second driving motor, and controls the second driving motor to drive the power head to move on the guide rail according to the tension value acquired by the tension monitoring device so as to balance the tension of the traction object.

In one embodiment, two idler wheels are further provided at a position corresponding to each of the driving means; each idler wheel surface is provided with a second meshing structure capable of meshing with the meshing side of the tractor;

when the standby position is adopted, the first meshing structure of the power head is arranged on one side of the traction device, the two idle wheels are arranged on the other side of the traction device, and the traction head can pass through the traction device without obstruction;

when the power head moves from the standby position to the working position, the first meshing structure of the power head pulls the pulling rod to pass between the two idle wheels, the pulling rod forms a U-shaped turn between the first meshing structure and the two idle wheels, and the pulling rod has a preset wrap angle on the first meshing structure.

In one embodiment, the drag head comprises:

the connecting part is connected with the carrier and arranged between the carrier and the towing object;

and the traction part is used for connecting the traction rod with the connecting part.

In one embodiment, the tow head is located at a central symmetrical position of the vehicle.

In one embodiment, the two driving devices are arranged at two opposite positions of the annular closed track, and the two driving devices are arranged on the annular closed track through the following structural forms:

a driving device is arranged on a mobile device which can carry the driving device to circularly switch at two positions of the circular track.

In one embodiment, the two driving devices are arranged at two opposite positions of the annular closed track, and the two driving devices are arranged on the annular closed track through the following structural forms:

and sharing the power head of one driving device with the power head of the other driving device by using the pushing structure, and pushing the two power heads to circularly switch at two positions of the annular track by using the pushing structure.

According to a second aspect of the present application, there is also provided a logistics transport system comprising a pulling device as described in any one of the above.

The beneficial effect that draw gear in this application has:

1. the application utilizes the annular track to bear the carrier, and the carrier moves along the track of the annular track after being exerted with the driving force. At least one traction head is arranged on the closed ring-shaped traction device and is used for connecting the carrier. The two driving devices avoid the traction head on the closed annular traction object in turn and drive the closed annular traction object to move uninterruptedly, so that the continuous and cyclic traction of the carrier is realized.

2. In the application, only the closed annular traction device, the traction head for connecting the carrier and the closed annular traction device and the two driving devices only comprising the pushing structure are used, so that the application has the advantages of simple structure and low production cost.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

FIG. 1 is a schematic diagram illustrating a traction device according to an embodiment of the present disclosure;

fig. 2 is a state diagram of the power head in the working position, the transition position, and the standby position according to an embodiment of the present application;

FIG. 3 is a state diagram illustrating a powerhead in an operating position, a transition position, and a standby position according to another embodiment of the present application;

FIG. 4 is a schematic diagram illustrating a configuration of a powerhead according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a pusher jack mechanism according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a traction head according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Fig. 1 is a schematic structural diagram of a traction device according to an embodiment of the present application. Referring to fig. 1, the traction apparatus includes an endless track 100, a traction head 200, a closed-loop traction apparatus 300, and two driving devices 400.

The circular track of the circular track 100 corresponds to the circular track of the closed circular pulling device 300, and the circular track 100 is used for carrying the vehicle and allowing the vehicle to move thereon.

The traction head 200 includes a fixed end and a traction end. Wherein, the traction end of the traction head 200 is connected to the closed ring-shaped traction device 300, and the fixed end is connected to the carrier 500. In the embodiment, the closed loop type pulling device 300 is used for driving the pulling head 200 to move, and the carrier 500 moves synchronously with the pulling head 200 through the force transmission of the pulling head.

The two driving devices 400 are used for respectively driving the closed loop pulling device 300 to rotate. The two driving devices 400 are respectively arranged at two preset positions of the circular track formed by the closed circular traction device 300, the two driving devices 400 are respectively provided with a power head 410 capable of driving the closed circular traction device 300, the power heads 410 are arranged on the same pushing structure 420, and the pushing structure 420 and the power head 410 can be matched to act to tension and drive the closed circular traction device 300.

Specifically, the process of the two driving devices 400 driving the closed loop pulling device 300 to rotate in turn is as follows:

when one of the driving devices 400 tensions and drives the closed loop traction device 300 to rotate, the other driving device 400 is in a standby state; after the traction head 200 passes through the driving device in the standby state, the pushing structure of the driving device in the standby state starts to push the power head to be close to the traction primer, tension and drive the closed annular traction primer, the pushing structure of the driving device in operation pushes the power head to be gradually far away from the traction primer, and the traction head enters the standby state after reaching the position capable of avoiding the traction head 200, so that the traction head can realize the unhindered rotation.

In the process that the two driving devices 400 continuously drive the closed loop type traction device 300, the traction head 200 rotates to enable the carrier 500 connected to the fixed end to rotate, so that the continuous circulation traction of the carrier 500 is realized.

As can be seen from the above technical solutions, the present application uses the circular track 100 to carry the carrier 500, and the carrier 500 moves along the track of the circular track after being applied with the driving force. At least one traction head is arranged on the closed ring-shaped traction device and is used for connecting the carrier. The two driving devices avoid the traction head on the closed annular traction object in turn and drive the closed annular traction object to move uninterruptedly, so that the continuous and cyclic traction of the carrier is realized. The traction device only comprises the closed annular traction device, the traction head for connecting the carrier and the closed annular traction device, and the two driving devices only comprising the pushing structure, so the traction device has the advantages of simple structure and low production cost.

In the embodiment of the application, the number of the traction heads on the closed ring-shaped traction primer can be 1, and can also be set to be 2 or more than 2 according to the use requirement. When the number of the traction heads is 2 or more than 2, the distribution mode of the traction heads on the closed ring-shaped traction head 300 needs to meet the following requirements: before one of the traction heads passes through the drive in the standby state, no traction head is allowed to pass through the transition point of the drive in operation.

The closed loop pulling device 300 in the present application includes, but is not limited to, a timing belt, a wire rope, or a chain. In one implementation, the powerhead has a first engagement structure for engaging a towing article, and the powerhead drives the towing article in an engagement drive. When the traction mechanism is a synchronous belt, a first meshing structure matched with the power head is a synchronous belt gear; when the traction rod is a steel wire rope, a first meshing structure matched with the power head is a friction wheel; when the traction rod is a chain, the first meshing structure matched with the power head is a chain wheel.

In one embodiment, the powerhead 410 of each drive 400 will include three settings: a working position, a transition position and a standby position. Fig. 2 is a state diagram of the power head 410 in the working position, the transition position, and the standby position according to an embodiment of the present disclosure. Referring to fig. 2, the work station refers to a position where the powerhead 410 can individually tension and drive the closed loop tractor 300, where the tractor cannot pass through the work station. The standby position is a position where the power head 410 is out of contact with the closed loop type pulling head 300, and the pulling head can pass through the standby position without hindrance. The transition position refers to a predetermined interval of the powerhead 410 between the active position and the standby position where the tractor head cannot be passed by the transition position. When one power head of the two driving devices is in a working position, the other power head is in a standby position; the two driving devices realize the driving switching of the traction object at the transition position.

In another embodiment, referring to fig. 3, fig. 3 is a state diagram illustrating the powerhead 410 in an operational position, a transition position, and a standby position according to another embodiment of the present application. Referring to fig. 3, two idler pulleys 700 are further provided at positions corresponding to each driving device 400. Each idler 700 is provided with a second engagement formation on a surface thereof engageable with the engaging side of the tractor.

When the power head is in the standby position, the first meshing structure of the power head is arranged on one side of the traction device, the two idler wheels 700 are arranged on the other side of the traction device, and the traction head can pass through without obstruction.

When the power head moves from the standby position to the working position, the first meshing structure of the power head pulls the pulling object to pass through between the two idle wheels 700, the pulling object forms a U-shaped turn between the first meshing structure and the two idle wheels 700, and the pulling object has a preset wrap angle on the first meshing structure.

In one embodiment, the close contact surface of the two idle wheels and the traction rope is provided with a second meshing structure, and when the traction rope is a synchronous belt, the second meshing structure matched with the two idle wheels is a smooth surface synchronous belt idle wheel; when the traction rod is a steel wire rope, the second meshing structure matched with the two idle wheels is a groove-shaped idle wheel; when the pulling rod is a chain, the second meshing structure matched with the two idle wheels is a sprocket idle wheel.

In the embodiment using the working position, the standby position, and the transition position, in order to realize the continuous circular rotation of the closed loop type pulling device 300, the two driving devices 400 are in the following working states: when one is in the working position, the other is in the standby position; the two drive devices 400 effect a drive switching of the closed loop stopper 300 in the transition position.

The following describes how the two driving devices 400 can switch the driving of the closed loop pulling device 300 at the transition position.

The driving device 400 currently at the standby position moves towards the working position until the power head 410 contacts the closed ring-shaped traction object 300, and the tension of the traction object 300 rises; synchronously, the tension of the tractor 300 is increased to cause the driving device 400 which is currently at the working position to start moving towards the standby position so as to reduce the tension of the tractor 300; during this brief period, the closed loop pulling means 300 is still driven by the driving means 400 in the working position.

When the tightening force of the closed loop traction device 300 is kept within the preset threshold range, the driving device 400 starting from the standby position continuously moves to the working position until the preset working position stops; the drive unit 400 from the operating position continues to move toward the standby position until the standby position stops. In this process, the two working heads of the driving device 400 exert tension on the closed loop type pulling device 300, and both the two working heads contact with the teeth of the closed loop type pulling device 300 and can drive the closed loop type pulling device 300 to rotate.

When the two driving devices 400 are switched, the tension of the closed loop type pulling device 300 needs to be detected in real time. When the tension of the closed loop traction device 300 exceeds a predetermined threshold, the driving device 400 starting from the standby position stops moving to the working position of the driving device 400, and the driving device 400 starting from the working position continues moving to the standby position; until the tightening force of the closed loop pulling means 300 falls back to the predetermined threshold, the two driving means 400 continue the predetermined movement. When the tension of the closed loop traction device 300 is lower than the predetermined threshold, the driving device 400 from the standby position continues to move to the operating position of the driving device 400, and the driving device 400 from the operating position stops moving to the standby position of the driving device 400; until the tightening force of the closed loop pulling means 300 falls back to the predetermined threshold, the two driving means 400 continue the predetermined movement.

The above process enables the two driving devices 400 to avoid the tractor 200 in turn and keep the closed loop tractor 300 at the tension within the predetermined threshold range all the time, thereby realizing the unobstructed rotation of the tractor 200.

In one embodiment, two driving devices 400 are disposed at two opposite positions of the endless closed track, and the two driving devices 400 obtain balanced standby and working time. In a more specific embodiment, the two driving devices 400 are divided at two equal points of the endless closed track, i.e. the same distance is used for the driving device 400 to reach the other driving device 400 in the clockwise direction and the counterclockwise direction. The driving paths of the two driving devices 400 are the same, and the standby time and the working time are set to be the same, so that the control method of the two driving devices 400 is simpler, and the calculation amount in the control process is saved.

It should be noted that, in the above embodiments, the arrangement manner in which the two driving devices are respectively disposed on both sides of the closed loop-shaped pulling device to avoid the pulling head and achieve continuous driving of the closed loop-shaped pulling device is merely exemplary, and in another embodiment, the two driving devices are disposed at two opposite positions of the annular closed track, which can also be achieved by the following structural forms: a driving device is arranged on a mobile device which can carry the driving device to circularly switch at two positions of the circular track. And in a further embodiment, the two driving devices are arranged at two opposite positions of the annular closed track, and the following structural forms can be further realized: and the power head of one driving device and the power head of the other driving device share one pushing structure, and the pushing structure pushes the two power heads to circularly switch at two positions of the annular track.

Fig. 4 is a schematic diagram illustrating a configuration of a powerhead 410 according to an embodiment of the present disclosure. Referring to FIG. 4, the powerhead 410 includes a first drive motor 411, a gear housing 412 coupled to an output shaft of the first drive motor 411, a bearing housing 413 located at one end of the gear housing 412, and a first engagement structure 414 located at one end of the bearing housing 413 and configured to mate with the closed loop retractor 300.

The power head 410 in the embodiment of the present application has a function of pushing the closed loop type pulling device 300, and also has a function of driving the closed loop type pulling device 300 during the pushing of the closed loop type pulling device 300, in one embodiment, the closed loop type pulling device 300 is a toothed synchronous belt structure, and the first engaging structure 414 is a gear engaged with a tooth surface of the synchronous belt.

Fig. 5 is a schematic structural view of a pusher jack according to an embodiment of the present application. Referring to fig. 5, the pusher-pusher mechanism 420 includes a support frame 421, a second driving motor 422, a lead screw 423, a guide rail 424, a spring 425 having a predetermined tension, and a tension monitoring device 426.

The support frame 421 is divided into a front part and a rear part, the spring 425 is arranged at the front part of the support frame 421, and the power head 410 is arranged at the rear part of the support frame 421. The spring 425, the tension monitoring device 426, and the powerhead 410 are connected in series such that the front and rear connections of the support frame 421 move together. In this embodiment, the front and rear are distinguished from each other with respect to the distance position of the second driving motor, the position close to the second driving motor is the front, and the position far from the second driving motor is the rear.

The connecting end of the screw 423 is connected with the output end of the second driving motor 422, the front part of the support frame 421 is arranged at the position where the screw 423 is far away from the connecting end, and the second driving motor 422 and the screw 423 are used for driving the front part of the support frame 421 to move.

When the lead screw 423 rotates and pushes the front of the support frame 421 to move, the spring 425 stretches, and pulls the power head 410 at the rear of the support frame 421 to move along the guide rail 424. The guide rail 424 is used for supporting and defining a moving path of the support frame 421, the support frame 421 can move back and forth along the guide rail 424 in a direction perpendicular to the engaging surface of the closed loop traction mechanism 300 under the driving of the second driving motor 422 and the lead screw 423, and the moving track of the power head 410 covers a working position, a transition position and a standby position at each one-way stroke of the support frame 421.

A tension monitoring device 426 connected in series between the spring 425 and the powerhead 410 measures the tension value of the lead screw 423. The tension monitoring device 426 is communicatively coupled to the second drive motor 422, and the second drive motor 422 controls the amount of movement of the powerhead 410 along the track 424 based on the tension value obtained by the tension monitoring device 426.

In the embodiment of the present application, the tension applied to the closed loop pulling device 300 is reflected by the tension value of the lead screw 423, so as to achieve the purpose of program control of the tension of the closed loop pulling device 300. The tension monitoring device 426 in the embodiment of the present application may be an electronic ruler for measuring the amount of extension and retraction of a spring, or a tension meter for measuring the tension value of the lead screw 423. It should be noted that the electronic ruler and the tension meter are only exemplary, and the tension monitoring device 426 may also adopt other structures capable of measuring the length change or the tension change of the spring 425, and the structure of the tension monitoring device 426 is not particularly limited in the present application.

In the embodiment of the present application, the spring 425 functions to improve the system adjustment performance of the pusher-jack mechanism, so that the adjustment of the tension value of the lead screw 423 (corresponding to the tension of the pulling rod 300) tends to be smooth.

In one form of construction of the pulling head, the pulling head comprises a coupling portion and a pulling portion. The connecting part is connected with the carrier and arranged between the carrier and the traction object. The traction part is used for connecting the traction rod and the connecting part. Fig. 6 is a schematic structural diagram of a traction head according to an embodiment of the present application. Referring to fig. 6, the traction head 200 includes a coupling plate 210, a first tooth plate 220, a second tooth plate 230, and a pressure plate 240. The first tooth plate 220 and the second tooth plate 230 are used to connect the open closed loop pulling device 300 into a closed loop pulling device 300. The pressing plate 240, the start end portion 310 of the closed loop type pulling mechanism 300, the first tooth plate 220, the connecting plate 210, the end portion (not shown due to shielding) of the closed loop type pulling mechanism 300, and the second tooth plate 230 are sequentially arranged and fixedly connected in the thickness direction or the length direction of the closed loop type pulling mechanism 300.

The connection part 600 is fixedly connected with the connection plate 210 and extends a predetermined length to a lower side of the traction part for connection with the carrier 500.

In another embodiment, the connecting part can also be formed integrally with the connecting plate of the pulling part. In an implementation scheme, the connecting portion 600 is further provided with a first pressing block 610, the first pressing block 610 is provided with a mounting surface, a groove penetrating through the first pressing block 610 is formed in the mounting surface, after the first pressing block 610 is detachably connected with the connecting portion 600, a rope-shaped object and the like can be clamped in the groove, and a carrier and the like can be added on the rope-shaped object to increase the transmission amount of the annular closed traction device.

It should be noted that the first pressing block 610 and the connecting portion 600 may be fixed by a nut, or may be fixed by other components or structures, which is not specifically limited in this application.

The traction head 200 shown in fig. 6 is located at the central symmetrical position of the carrier 500. It should be noted that the present application is only exemplary for the towing head 200 to be disposed at the upper central symmetrical position of the carrier 500, and as another embodiment, the towing head 200 may also be located at one side of the carrier 500. The setting position of the traction head 200 relative to the carrier 500 is not specifically limited, and all the setting positions capable of driving the carrier 500 to move fall into the protection range of the present application.

In another aspect, the present application further provides a logistics transportation system, which includes a traction apparatus adopting any one of the above structures.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.