An AGV cart for pallet handling and its usage method

Abstract

The present invention relates to a pallet handling AGV trolley and its usage method. The AGV trolley includes a bearing plate, a lifting mechanism, a wheel set mechanism, a driving mechanism, a speed reduction mechanism, and a control mechanism. The lifting mechanism includes a hydraulic cylinder disposed on the bearing plate and a guiding assembly disposed on both sides of the hydraulic cylinder. The wheel set mechanism includes a driving wheel and a driven wheel disposed on the bearing plate, and the driving wheels are symmetrically disposed on both sides of the bearing plate. The driving mechanism and the speed reduction mechanism are disposed on the bearing plate. Each driving wheel is respectively connected to a driving mechanism, and a speed reduction mechanism is disposed between the driving mechanism and the driving wheel. The control mechanism respectively controls each driving mechanism to drive the corresponding driving wheel to rotate through the speed reduction mechanism. Compared with the prior art, the present invention has the advantages of high efficiency, low cost, no need to cooperate with a bracket, strong flexibility, and reduction of site occupation, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of AGV equipment, and particularly relates to a pallet handling AGV trolley and its usage method. Background Art

[0002] An AGV trolley refers to a transport vehicle equipped with automatic guiding devices such as electromagnetic or optical devices, capable of traveling along a specified guiding path, having safety protection and various transfer functions, without a driver in industrial applications, and powered by a rechargeable battery. There are various types of AGV trolleys. Classified by their transfer methods, they include lift type, forklift type, etc.

[0003] A pallet is a base made for facilitating the placement of scattered items and shipping requirements. Goods are placed on the pallet and are in a ready state to be transferred into motion at any time. Most lift type AGV trolleys adopt scissor lift assemblies, and the overall height of the trolley is relatively high. When using a lift type AGV trolley for goods handling, the pallet carrying the goods needs to be pre-placed on a bracket fixed to the ground to increase the height of the pallet. The entire lift type AGV trolley is inserted under the bracket to lift the pallet, and then it moves for the handling operation. This solution has relatively high efficiency, but it needs to cooperate with the bracket, occupies space, and has weak flexibility. When using a forklift type AGV trolley for goods handling, the fork arms used for loading on the AGV trolley are inserted into the pallet, and the fork arms are driven by the driving device to move upward, thereby lifting the pallet and the goods on it. The AGV trolley moves to complete the handling operation. This solution does not need to cooperate with the bracket, but has relatively low efficiency and high manufacturing cost of the trolley. Summary of the Invention

[0004] The purpose of the present invention is to provide a pallet handling AGV trolley and its usage method for efficiently handling pallets and reducing costs.

[0005] The purpose of the present invention can be achieved through the following technical solutions: A pallet handling AGV trolley includes a carrying plate, a lifting mechanism, a wheel set mechanism, a driving mechanism, a speed reduction mechanism, and a control mechanism;

[0006] The lifting mechanism includes a hydraulic cylinder arranged on the carrying plate and guiding components arranged on both sides of the hydraulic cylinder;

[0007] The wheel set mechanism includes driving wheels and driven wheels arranged on the carrying plate, and the driving wheels are symmetrically arranged on the left and right sides of the carrying plate;

[0008] The driving mechanism and the speed reduction mechanism are arranged on the carrying plate. Each driving wheel is respectively connected to a driving mechanism, and a speed reduction mechanism is arranged between the driving mechanism and the driving wheel. The control mechanism respectively controls each driving mechanism to drive the corresponding driving wheel to rotate through the speed reduction mechanism.

[0009] Preferably, the driven wheels are symmetrically arranged at the front and rear ends of the carrier plate, and have functions such as auxiliary support and steering. Further preferably, the driven wheels are universal wheels.

[0010] Preferably, the driving wheel is arranged at the middle position of the carrier plate (along the moving direction of the AGV vehicle).

[0011] Preferably, the reduction mechanism includes a first-stage reduction component and a second-stage reduction component connected to each other. Through the cooperative arrangement of the first-stage reduction component and the second-stage reduction component in the present invention, the driving mechanism undergoes two effective speed reductions, increasing the torque, reducing the rotational speed of the driving wheels, and improving the driving effect. Preferably, in order to reduce the volume and facilitate assembly, the first-stage reduction component and the second-stage reduction component can be pre-assembled in the same reduction box.

[0012] Further preferably, the first-stage reduction component is connected to the driving mechanism, and the first-stage reduction component includes a reduction gear; the second-stage reduction component is connected to the driving wheel, and the second-stage reduction component includes a spiral bevel gear set. Preferably, the reduction gear is a servo reduction gear. The tooth part of the spiral bevel gear set is in an inclined circular arc shape, which can achieve a better transmission effect with a smaller volume and provide sufficient power for the driving wheel. The spiral bevel gear set is preferably a ground spiral bevel gear.

[0013] Even more preferably, the spiral bevel gear set includes a small gear connected to the reduction gear and a large gear connected to the driving wheel, the small gear meshes with the large gear, the wheel set mechanism includes two driving wheels, and the large gears connected to the two driving wheels are coaxially arranged.

[0014] Preferably, the spiral bevel gear sets connected to the two driving wheels are oppositely arranged in the same gearbox.

[0015] The arrangement mode of the spiral bevel gear set in the present invention enables each spiral bevel gear set to reduce the overall volume without interference, saving the occupied space.

[0016] Preferably, a set of jacking mechanisms are arranged at the front and rear ends of the carrier plate respectively. The hydraulic cylinders in the jacking mechanisms on the same carrier plate are connected to a hydraulic pump through an oil supply pipeline. The hydraulic pump is arranged in the machine base, and a battery is also arranged in the machine base. To reduce the occupied space of the oil supply pipeline, the oil supply pipeline can be arranged through the gearbox. The hydraulic pump is composed of a motor and an oil supply tank. The machine base has the functions of fixing and storing, and the power supply of the AGV vehicle, such as a lithium battery, can be placed therein.

[0017] In the present invention, two sets of lifting mechanisms on the same carrier plate are configured with one hydraulic pump. When the AGV cart includes multiple carrier plates, it is equivalent to each carrier plate being equipped with one hydraulic pump. Compared with multiple carrier plates sharing one hydraulic pump, this solution can greatly improve the synchronization and stability of the lifting mechanisms on each carrier plate, preventing the lifting mechanisms on each carrier plate from lifting out of sync due to uneven oil distribution or flow rate differences, etc., which affects the stability of the handling process.

[0018] Preferably, the oil supply pipeline is arranged inside the carrier plate without increasing the overall volume of the AGV cart.

[0019] Preferably, the tops of the hydraulic cylinders in each of the lifting mechanisms are commonly connected to a lifting plate, and the lifting plate moves up and down along the guiding assembly under the drive of the hydraulic cylinder. The setting of the guiding assembly can improve the stability and reliability of the up and down movement of the lifting plate, and further improve the stability and reliability of the AGV cart during the handling process of the pallet.

[0020] More preferably, the guiding assembly includes linear bearings.

[0021] Preferably, the carrier plate has a concave structure with higher ends and lower middle. The lifting plate is arranged at the middle position of the carrier plate, so that when the lifting plate is not raised, it is only slightly higher than the two ends of the carrier plate, without affecting the insertion of the carrier plate under the pallet.

[0022] Preferably, the driving mechanism includes a servo motor.

[0023] Preferably, the pallet handling AGV cart includes one carrier plate.

[0024] A method for using the above-mentioned pallet handling AGV cart includes the following steps: The control mechanism controls the operation of each driving mechanism to drive the driving wheels on both sides of the carrier plate to rotate, and transports the AGV cart to the pallet stacking place. Subsequently, the carrier plate is inserted under the pallet, and the lifting mechanism lifts the pallet for handling. After reaching the designated position, the lifting mechanism puts down the pallet, and then the control mechanism controls the operation of each driving mechanism to continue, and the AGV cart continues to move forward.

[0025] Preferably, the pallet handling AGV cart includes two or more parallel and spaced-apart carrier plates, and the carrier plates are connected by a connecting mechanism.

[0026] A method for using the above-mentioned pallet handling AGV cart includes the following steps: The control mechanism controls the operation of each driving mechanism to drive each driving wheel to rotate, and transports the AGV cart to the pallet stacking place. Subsequently, the carrier plate is inserted under the pallet, and the lifting mechanism lifts the pallet for handling. After reaching the designated position, the lifting mechanism puts down the pallet, and then the control mechanism controls each driving mechanism to reverse, and the AGV cart withdraws.

[0027] When a turn is required, the speed difference of each driving wheel is controlled by adjusting different driving mechanisms through a control mechanism to achieve a turn.

[0028] Further preferably, the pallet handling AGV cart includes two parallel and spaced-apart carrier plates.

[0029] Preferably, the control mechanism includes a PLC controller, and the PLC controller is connected to the driving mechanism.

[0030] Preferably, the size of the carrier plate in the pallet handling AGV cart does not exceed the fork holes under the pallet, and the carrier plate is directly inserted under the pallet.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] 1. In the AGV cart of the present invention, the lifting mechanism and the driving mechanism are integrated onto the carrier plate, with a compact structure, small height and volume. The carrier plate can be directly inserted under the pallet to achieve pallet handling through lifting. The operation is simple, overcoming the disadvantages of lifting-type and forklift-type AGV carts, with high efficiency, low cost, no need to cooperate with brackets, strong flexibility, and reduced site occupation;

[0033] 2. Through the setting of the speed reduction mechanism in the present invention, the driving mechanism can provide sufficient driving force for the driving wheels in a smaller space, which is beneficial to the fast and stable handling of pallets by the AGV cart;

[0034] 3. Through the combined setting of the primary speed reduction component and the secondary speed reduction component in the present invention, the driving mechanism undergoes two effective speed reductions, the speed reduction ratio is doubled, the torque is increased, the rotational speed of the driving wheels is reduced, and the driving effect is improved;

[0035] 4. Each driving wheel in the present invention is driven by a separate driving mechanism and can have different rotational speeds under the control of the control mechanism, with more flexible operation and the ability to achieve a turn in place;

[0036] 5. One hydraulic pump is configured for the lifting mechanism on the same carrier plate in the present invention. When the AGV cart includes multiple carrier plates, it is equivalent to each carrier plate being equipped with a hydraulic pump. Compared with multiple carrier plates sharing one hydraulic pump, this solution can greatly improve the synchronization and stability of the lifting mechanisms on each carrier plate;

[0037] 6. The driving wheels are arranged at the middle position of the carrier plate in the present invention, so that the power of the AGV cart is at the middle position, which is beneficial to improving the stability during the movement process and reducing the turning radius;

[0038] 7. The lifting plate in the present invention is driven by two groups of lifting mechanisms arranged at both ends of the carrier plate, with stronger balance and stability;

[0039] 8. The present invention can be four-wheel driven, with strong power;

[0040] 9. The design of the present invention is flexible and can be in the form of a single leg or multiple legs (single load-bearing plate or multiple load-bearing plates), with a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Top view of the pallet handling AGV cart in Embodiment 1;

[0042] Figure 2 Side view of the pallet handling AGV cart in Embodiment 1;

[0043] Figure 3 Top view of the pallet handling AGV cart in Embodiment 1 after removing the lifting plate;

[0044] Figure 4 Partial structural schematic diagram of the pallet handling AGV cart in Embodiment 1 after removing the lifting plate, load-bearing plate and machine base;

[0045] Figure 5 Structural schematic diagram of the driving mechanism and deceleration mechanism in Embodiment 1;

[0046] Figure 6 Structural schematic of the pallet handling AGV cart in Embodiment 3 Figure 1 ;

[0047] Figure 7 Structural schematic of the pallet handling AGV cart in Embodiment 3 Figure 2 ;

[0048] Figure 8 Side view of the pallet handling AGV cart in Embodiment 3;

[0049] In the figure: 1 - load-bearing plate, 2 - lifting mechanism, 21 - hydraulic cylinder, 22 - guiding component, 3 - wheel set mechanism, 31 - driving wheel, 32 - driven wheel, 4 - driving mechanism, 5 - deceleration mechanism, 51 - primary deceleration component, 52 - secondary deceleration component, 6 - oil supply pipeline, 7 - hydraulic pump, 8 - machine base, 9 - battery, 10 - lifting plate. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0050] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are implemented on the premise of the technical solution of the present invention, and the detailed implementation manners and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0051] Embodiment 1

[0052] A pallet handling AGV cart, as Figures 1 - 2As shown in the figure, it includes two parallel and spaced-apart bearing plates 1. The two bearing plates 1 are connected by a connecting mechanism. Each bearing plate 1 is provided with a wheel set mechanism 3 and a lifting plate 10. Among them, the wheel set mechanism 3 includes a driving wheel 31 arranged at the middle position of the bearing plate 1 and universal driven wheels 32 arranged at the front and rear ends of the bearing plate 1. The lifting plate 10 is provided with a slot for the driving wheel 31 to pass through.

[0053] Specifically, as Figures 3 - 4 shown in the figure, at the front and rear ends of the bearing plate 1 (based on the traveling direction of the trolley), a lifting mechanism 2 for realizing the lifting of the lifting plate 10 is provided. Each lifting mechanism 2 includes a hydraulic cylinder 21 and guiding components 22 arranged on both sides of the hydraulic cylinder 21. The hydraulic cylinders 21 on the same bearing plate 1 are connected to a hydraulic pump 7 through an oil supply pipeline 6, which can improve the synchronism of the hydraulic cylinders 21 on the two bearing plates 1. In this embodiment, the two hydraulic pumps 7 are both arranged in the machine base 8. The machine base 8 is arranged on the connecting mechanism between the two bearing plates 1. The battery 9 is arranged in the machine base 8 and serves as the power source for each component (such as motors, pumps, and controllers) on the AGV trolley. In this embodiment, the battery 9 is a lithium battery. The tops of the hydraulic cylinders 21 in the lifting mechanisms 2 at both ends of the bearing plate 1 are commonly connected to the lifting plate 10. The lifting plate 10 is directly lifted by hydraulic pressure to achieve fast and stable lifting. Moreover, the lifting plate 10 is connected to the guiding components 22 to further improve the stability during the lifting process. The hydraulic cylinder 21 includes a cylinder body and a piston rod arranged on the cylinder body. The lifting plate 10 is connected to the piston rod, and the lifting of the piston rod can be controlled by direct current.

[0054] On the left and right sides of each bearing plate 1, 2 driving wheels 31 are symmetrically arranged. Each driving wheel 31 is respectively connected with a set of reduction mechanism 5 and driving mechanism 4. The driving mechanism 4 and the reduction mechanism 5 are both arranged on the bearing plate 1, as Figure 5 shown in the figure, the driving mechanism 4 is a servo motor. The reduction mechanism 5 includes a primary reduction component 51 and a secondary reduction component 52. Among them, the primary reduction component 51 is a servo reducer connected to the servo motor. The secondary reduction component 52 is a spiral bevel gear set connected to the driving wheel 31, including a pair of meshing large gears and small gears. Among them, the small gear is connected to the servo reducer, and the large gear is connected to the driving wheel 31. The spiral bevel gear sets configured for the 2 driving wheels 31 are relatively arranged in the same gearbox. Moreover, the 2 driving wheels 31 and the 2 large gears are coaxially arranged.

[0055] As Figure 2 shown in the figure, the bearing plate 1 has a concave structure with high ends and low middle. The lifting plate 10 is arranged at the middle position of the bearing plate 1, so that when the lifting plate 10 is not lifted, it is only slightly higher than the two ends of the bearing plate 1, without affecting the insertion of the bearing plate 1 under the pallet.

[0056] In this embodiment, the height of the highest points (both ends) of the carrier plate 1 is 80 - 120 mm, the width is 180 - 220 mm, the distance between two adjacent carrier plates 1 is 260 - 340 mm, the height of the machine base 8 is 180 - 220 mm, the diameter of the driving wheel 31 is 100 - 130 mm, the reduction ratio of the servo reducer is 3 - 15:1, and the reduction ratio of the spiral bevel gear set is 2 - 3:1.

[0057] In this embodiment, general components in the field such as a power supply, a wireless communication system, a path tracking sensor, and a protection sensor are provided on the AGV cart, which can communicate with the central control system, report the operating status, and obtain and execute operating instructions. The control mechanism includes PLC controllers arranged on each servo motor, and each PLC controller adjusts the rotation speed of the corresponding servo motor according to the instructions, thereby realizing the control of the rotation speed of each driving wheel 31.

[0058] When using the AGV cart of this embodiment to carry pallets, the control mechanism controls the operation of each driving mechanism 4, drives each driving wheel 31 to rotate, transports the AGV cart to the pallet stacking place. Subsequently, the carrier plate 1 is inserted under the pallet, and the hydraulic cylinder 21 drives the lifting plate 10 to rise, lifting the pallet for transportation. After reaching the designated position, the hydraulic cylinder 21 drives the lifting plate 10 to descend, putting down the pallet. Subsequently, the control mechanism controls each driving mechanism 4 to reverse, and the AGV cart withdraws, completing the pallet carrying work.

[0059] Particularly, the AGV cart of this embodiment drives four driving wheels 31 to rotate respectively through four sets of driving mechanisms 4, with strong power, and can realize the differential control of the rotation speed of each driving wheel 31 by adjusting different driving mechanisms 4 through the control mechanism, realizing operations such as turning in place, and having a smaller turning radius.

[0060] Embodiment 2

[0061] In this embodiment, the guiding component is a linear bearing, and the rest of the structure is the same as that of Embodiment 1.

[0062] Embodiment 3

[0063] A pallet-carrying AGV cart, as Figures 6 - 8 shown, includes a carrier plate 1, and a hydraulic pump 7 and a machine base 8 are also arranged on the carrier plate 1. The machine base 8 and the carrier plate 1 are integrally formed and have the same height as the two ends of the carrier plate 1, and the rest of the structure is the same as that of Embodiment 1.

[0064] When using the AGV cart of this embodiment to carry pallets, the control mechanism controls the operation of each driving mechanism 4, drives the driving wheels 31 on the left and right sides of the bearing plate 1 to rotate, transports the AGV cart to the pallet stacking place. Subsequently, the bearing plate 1 is inserted under the pallet, and the hydraulic cylinder 21 drives the lifting plate 10 to rise, lifting the pallet for transportation. After reaching the designated position, the hydraulic cylinder 21 drives the lifting plate 10 to descend, putting down the pallet. Subsequently, the control mechanism controls the continuous operation of each driving mechanism 4, and the AGV cart continues to move forward to complete the pallet handling work.

[0065] In this embodiment, due to the reduction in the height of the machine base 8, the entire AGV cart can directly pass through the pallet without having to reverse, further improving the work efficiency.

[0066] Specifically, the AGV cart of this embodiment drives the rotation of two driving wheels 31 through two sets of driving mechanisms 4 respectively. When turning is required, the control mechanism makes the rotational speed of one driving wheel greater than that of the other driving wheel through the driving mechanism 4, and the AGV cart can be turned around the driving wheel with a smaller rotational speed.

[0067] The above description of the embodiments is for the convenience of those of ordinary skill in the art to understand and use the present invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and the improvements and modifications made by those skilled in the art without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. An AGV cart for pallet handling, characterized in that, It includes a carrier plate (1), a jacking mechanism (2), a wheel set mechanism (3), a driving mechanism (4), a speed reduction mechanism (5) and a control mechanism; The jacking mechanism (2) includes a hydraulic cylinder (21) arranged on the carrier plate (1) and a guiding component (22) arranged on both sides of the hydraulic cylinder (21); The wheel set mechanism (3) includes a driving wheel (31) and a driven wheel (32) arranged on the carrier plate (1), and the driving wheels (31) are symmetrically arranged on both sides of the carrier plate (1); The driving mechanism (4) and the speed reduction mechanism (5) are arranged on the carrier plate (1). Each driving wheel (31) is respectively connected with a driving mechanism (4), and a speed reduction mechanism (5) is arranged between the driving mechanism (4) and the driving wheel (31). The control mechanism respectively controls each driving mechanism (4) to drive the corresponding driving wheel (31) to rotate through the speed reduction mechanism (5); One set of jacking mechanism (2) is arranged at each end of the carrier plate (1). The hydraulic cylinders (21) in the jacking mechanism (2) on the same carrier plate (1) are connected to a hydraulic pump (7) through an oil supply pipeline (6). The hydraulic pump (7) is arranged in a machine base (8), and a battery (9) is also arranged in the machine base (8); The top of the hydraulic cylinder (21) in the jacking mechanism (2) is connected with a jacking plate (10), and the jacking plate (10) moves up and down along the guiding component (22) under the drive of the hydraulic cylinder (21); the guiding component (22) includes a linear bearing; the driving mechanism (4) includes a servo motor; the driven wheels (32) are symmetrically arranged at both ends of the carrier plate (1); The speed reduction mechanism (5) includes a first-stage speed reduction component (51) and a second-stage speed reduction component (52) connected to each other; The first-stage speed reduction component (51) is connected to the driving mechanism (4) and includes a speed reducer; the second-stage speed reduction component (52) is connected to the driving wheel (31) and includes a spiral bevel gear set; The speed reducer is a servo speed reducer; The spiral bevel gear sets connected to the two driving wheels (31) are relatively arranged in the same gearbox; the spiral bevel gear set includes a small gear connected to the speed reducer and a large gear connected to the driving wheel (31). The small gear meshes with the large gear. The wheel set mechanism (3) includes two driving wheels (31), and the large gears connected to the two driving wheels (31) are coaxially arranged; The height of the highest point of the carrier plate (1) is 80 - 120 mm, the width is 180 - 220 mm, the diameter of the driving wheel (31) is 100 - 130 mm, the reduction ratio of the servo speed reducer is 3 - 15:1, and the reduction ratio of the spiral bevel gear set is 2 - 3:

1.

2. The AGV cart for pallet handling according to claim 1, characterized in that, The pallet handling AGV cart includes one carrier plate (1).

3. The AGV cart for pallet handling according to claim 1, characterized in that, The pallet handling AGV cart includes two or more carrier plates (1) arranged in parallel and at intervals, and the carrier plates (1) are connected by a connecting mechanism.

4. A method for using the AGV cart for pallet handling according to claim 2, characterized in that, It includes the following steps: The control mechanism controls the operation of each driving mechanism (4), drives the driving wheels (31) on both sides of the carrier plate (1) to rotate, transports the AGV vehicle to the pallet stacking place. Subsequently, the carrier plate (1) is inserted under the pallet, and the lifting mechanism (2) lifts the pallet for handling. After reaching the designated position, the lifting mechanism (2) puts down the pallet. Subsequently, the control mechanism controls the continued operation of each driving mechanism (4), and the AGV vehicle continues to move forward.

5. A method for using the AGV cart for pallet handling according to claim 3, characterized in that, It includes the following steps: The control mechanism controls the operation of each driving mechanism (4), drives the driving wheels (31) to rotate, transports the AGV vehicle to the pallet stacking place. Subsequently, the carrier plate (1) is inserted under the pallet, and the lifting mechanism (2) lifts the pallet for handling. After reaching the designated position, the lifting mechanism (2) puts down the pallet. Subsequently, the control mechanism controls the reverse rotation of each driving mechanism (4), and the AGV vehicle withdraws.

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