Carrying robot

Abstract

The utility model relates to a transfer robot which comprises a frame and a pallet fork mechanism, the front portion of a pallet fork is divided into a fork tip and a fork plate transition portion, the bottom face of the fork tip is higher than the bottom face of the fork plate transition portion, and the joint between the fork tip and the fork plate transition portion is in transition through an inclined face. The bottom of the fork plate transition part is of a flat straight line structure and used for guiding the bottom of the pallet fork to make contact with a tray. The bottom surface of the fork plate transition part is the lowest part of the pallet fork; the joint of the fork plate transition part and the rear part of the pallet fork is transited through an inclined surface; and the connecting rod locking mechanism is used for locking the load wheel assembly in a suspended state when the pallet fork enters or retreats from the tray. According to the scheme, based on pure mechanical structure matching, through the synergistic effect of the fork plate transition part, the inclined plane and the rolling wheels, the trays with beams at the bottoms such as American-standard trays can pass at low speed and constant speed.

Description

Technical Field

[0001] This utility model relates to an AGV vehicle, specifically a material handling robot. Background Technology

[0002] In recent years, material handling robots have been widely used in the logistics and warehousing field. However, their adaptability to pallets with crossbeams at the bottom (such as ASME pallets and grid pallets) has significant shortcomings. Taking ASME pallets as an example, ASME pallets dominate the global market due to their mature technology and low cost. However, the uniform and low-speed movement characteristics of existing material handling robots when entering and exiting pallets make it difficult for them to smoothly enter and exit ASME pallets. This is especially true for empty ASME pallets. Because empty pallets are relatively light and ASME pallets have multiple upward protruding structures at the bottom, the forks can easily get stuck on the pallet and move along with it when entering or exiting. This makes it difficult to stably enter and exit ASME pallets, forcing users to use non-standard pallets or customized solutions, which significantly increases the cost of use.

[0003] Existing technologies also offer solutions for American standard pallets, which generally require a separate power source to raise the forks to facilitate pallet entry and exit. For example, the industrial handling vehicle disclosed in CN118479396A uses a lifting mechanism to tilt the vehicle body to achieve double-sided pallet picking. However, it relies on hydraulic or electric power sources, has a complex structure, and consumes a lot of energy. Utility Model Content

[0004] This utility model provides a material handling robot that does not require an additional power source. It uses a purely mechanical structure to allow the forks to smoothly enter and exit American standard pallets, solving the problem of easy jamming when forklift robots enter and exit pallets under the characteristics of uniform and low-speed movement. It is also low in cost.

[0005] A transport robot, comprising,

[0006] Frame,

[0007] The fork mechanism, which is slidably and liftingly mounted on the vehicle frame, includes the fork carriage and the forks mounted on the fork carriage;

[0008] The load wheel assembly includes a first wheel frame and a load wheel mounted on the first wheel frame. The load wheel assembly is driven by a linkage mechanism to switch between a loaded state and a suspended state.

[0009] The front of the fork is divided into the fork tip and the fork plate transition section. The fork tip is located at the very front of the fork, and its bottom surface is higher than the bottom surface of the fork plate transition section. The connection between the fork tip and the fork plate transition section is a beveled transition. The bottom of the fork plate transition section is a flat straight structure, which is used to guide the contact between the bottom of the fork and the pallet. The bottom surface of the fork plate transition section is the lowest point of the fork, and the connection between the fork plate transition section and the rear of the fork is a beveled transition.

[0010] It also includes a linkage locking mechanism for locking the load wheel assembly in a suspended state during the entry or exit of the forks from the pallet.

[0011] Preferably, a guide wheel assembly is provided at the junction of the fork tip and the fork plate transition section.

[0012] Preferably, the load wheel in the suspended state is located at the front of the fork plate transition section, and its bottom protrudes downward from the fork plate transition section; a roller assembly is provided in the middle or rear of the fork plate transition section, and the bottom of the roller assembly protrudes from the bottom of the fork plate transition section.

[0013] Preferably, the length of the fork plate transition is greater than the width of the widest gap between adjacent crossbeams of the matched pallet.

[0014] Preferably, the inner side of the first wheel frame is provided with an upwardly protruding clearance part, which is located near the long connecting rod; after the forks enter the pallet, the load wheel assembly 30 is located at the first gap on the pallet, and during the process of switching from the suspended state to the load-bearing state, there is always a gap between the first wheel frame and the edge of the first gap.

[0015] Preferably, the linkage locking mechanism includes a limiting member and a limiting seat, and the linkage mechanism includes a rocker arm and a long rocker arm. The limiting member is fixed on the rocker arm, and one end of the limiting member extends into the first space of the limiting seat. The limiting member moves with the rocker arm within the first space of the limiting seat. When the load wheel is suspended, the limiting member abuts against the first side of the first space, and the limiting member has a tendency to continue moving towards the first side.

[0016] Preferably, the first wheel carrier of the load wheel is connected to the fork at a first hinge point, the first wheel carrier is hinged to the linkage mechanism at a second hinge point, and the roller assembly is located at the second hinge point.

[0017] Preferably, the guide wheel assembly includes multiple lifting guide wheels, which are guided along the stepped inclined surface.

[0018] Preferably, the guide wheel assembly includes a second wheel carrier, and multiple lifting guide wheels are mounted on the forks via the same second wheel carrier.

[0019] As a preferred option, the multiple lifting guide wheels are divided into two groups, and the two groups of lifting guide wheels are installed on both sides of the second wheel frame and staggered.

[0020] In the above solution, the fork tips, fork plate transition section, and rear of the forks are designed with different thicknesses to form guide ramps at the front and rear. These ramps guide the forks to smoothly traverse the steps when entering and exiting the pallet, preventing the fork tips from colliding with the pallet's lower crossbeam. The bottom of the fork plate transition section is a straight line, occupying the relatively longer end of the front of the pallet, serving as a transition line for the fork plate entering and exiting the pallet, preventing collisions with the pallet's internal irregularities. This pallet entry and exit solution does not have an independent power source; it relies on a purely mechanical structure, utilizing the coordinated action of the fork plate transition section, ramps, and rollers to achieve low-speed, uniform entry and exit of American standard pallets. Compared to solutions requiring an additional power source, the control is much simpler. Attached Figure Description

[0021] Figure 1 A structural diagram of a US standard pallet at one angle;

[0022] Figure 2 for Figure 1 Another structural diagram;

[0023] Figure 3 This is a schematic diagram of the structure of this application;

[0024] Figure 4 A schematic diagram of a structure for a pallet truck to carry a US standard pallet;

[0025] Figure 5 for Figure 4 A sectional view;

[0026] Figure 6 One of the schematic diagrams illustrating the process of forks entering a US standard pallet;

[0027] Figure 7 This is the second illustration of the process of the forks entering the American Standard pallet.

[0028] Figure label:

[0029] Pallet 10, crossbeam 11, longitudinal beam 12,

[0030] Fork mechanism 20, fork carriage 21, forks 22, fork tips 221, fork plate transition section 222, roller assembly 23, guide wheel assembly 24, second wheel frame 241, lifting guide wheel 242.

[0031] Load-bearing wheel assembly 30, first wheel frame 31, arc-shaped clearance part 311, load-bearing wheel 32.

[0032] Linkage mechanism 40, swing arm 41, long connecting rod 42

[0033] Linkage locking mechanism 50, limit component 51, limit seat 52, first space 521. Detailed Implementation

[0034] The present application will be further described in detail below through specific embodiments and with reference to the accompanying drawings.

[0035] American Standard Pallets

[0036] The American Standard Pallet 10 (US Standard Pallet 10) is a standardized pallet widely used in North America, primarily for logistics, warehousing, and cargo transportation. For example... Figure 1-2 As shown, the American Standard Pallet 10 has load-bearing surfaces on both the top and bottom, and is supported in the middle by longitudinal beams 12 and crossbeams 11. There are three longitudinal beams 12 at the bottom, forming two rows of fork holes for the forklifts of the pallet truck to enter.

[0037] Pallet loading / unloading mechanism

[0038] like Figure 3 As shown, the pallet loading / unloading mechanism includes a fork mechanism 20, a linkage mechanism 40, a load wheel assembly 30, and a linkage locking mechanism 50. The fork mechanism 20 includes a fork carriage 21 and forks 22 mounted on the fork carriage 21. The fork carriage 21 is mounted on the vehicle frame and has a stroke for vertical movement relative to the vehicle frame, driven by a lifting mechanism to move up and down along the vehicle frame. In this embodiment, the lifting mechanism can be a hydraulic cylinder or an electric cylinder. In this embodiment, the fork carriage 21 refers to the mechanism that mounts the forks on the vehicle frame and drives their lifting and lowering. For example, in one specific embodiment, the pallet truck frame is divided into a front frame and a rear frame. The forks are welded and fixed to the front frame, and the front frame and rear frame are connected by rollers and grooves. The front frame can be driven by the lifting structure to move up and down along the rear frame. In this embodiment, the front frame is the fork carriage described herein.

[0039] In this embodiment, the front of the fork 22 is divided into a fork tip 221 and a fork plate transition portion 222. The fork tip 221 is located at the foremost end of the fork 22, and its width is relatively narrow to facilitate entry into the pallet 10. The bottom surface of the fork tip is higher than the bottom surface of the fork plate transition portion 222, so the connection between the fork tip 221 and the fork plate transition portion 222 is a beveled transition. This beveled transition facilitates the fork 22's climbing guidance in cooperation with the bottom step of the pallet 10 during its entry into the pallet 10. In a preferred embodiment, a guide wheel assembly 24 is provided at the connection between the fork tip 221 and the fork plate transition portion 222 to reduce the friction between the fork 22 and the pallet 10 through rolling friction. Figure 3 As shown, the bottom of the fork plate transition section 222 is a long straight line to help the forks 22 avoid jamming due to unevenness at the bottom of the fork plate during the process of entering and exiting the pallet 10. In addition, the fork plate transition section 222 is the thickest part of the forks 22, and the connection between the fork plate transition section 222 and the fork plate behind it also forms a transition slope, which can also play a guiding role when the forks 22 enter and exit the pallet 10 and pass through the steps.

[0040] See Figure 4For American standard pallets, several gaps are formed between adjacent crossbeams at the bottom of the pallet. The length of the fork plate transition section 222 is greater than the width of the widest gap to prevent the forks from getting stuck in the crossbeam gaps during the movement of the forks.

[0041] The linkage mechanism 40 includes a rocker arm 41 and a long connecting rod 42. The rocker arm 41 has three hinged ends, and the relative positions of the three hinged ends on the rocker arm 41 are always fixed. The first hinged end of the rocker arm 41 is hinged to the vehicle frame, the second hinged end of the rocker arm 41 is hinged to the fork carriage 21, and the third hinged end of the rocker arm 41 is hinged to one end of the long connecting rod 42. While the fork mechanism 20 moves up and down, the second hinged end rotates in a circle around the first hinged end, driving the third hinged end to drive the long connecting rod 42 to move in the horizontal direction, thereby driving the first wheel frame 31 connected to the front end of the long connecting rod 42 to move.

[0042] In specific embodiments, the specific structure of the linkage mechanism 40 and the connection method between it and the fork mechanism 20 can adopt, for example, those disclosed in publication numbers CN117658023A or CN118723873A.

[0043] The load wheel assembly 30 includes a first wheel frame 31 and a load wheel 32 mounted on the first wheel frame 31. The load wheel assembly 30 is driven by a linkage mechanism 40 to switch between a loaded state and a suspended state. In the loaded state, the load wheel 32 extends from below the forks 22 and contacts the ground, as shown below. Figure 5 As shown; in the suspended state, the load wheel 32 retracts into the fork 22 to prevent the load wheel assembly 30 from obstructing the entry and exit of the pallet 10. The position of the load wheel 32 in the suspended state is as follows: Figure 3 , 6 As shown in Figure -7.

[0044] The first wheel frame 31 is provided with a first hinge point and a second hinge point on the side near the long connecting rod 42. The first wheel frame 31 is hinged to the fork 22 at the first hinge point or the second hinge point, and connected to one end of the long connecting rod 42 at the other hinge point, so that the linkage mechanism 40 can drive the load wheel assembly 30 to switch between the loaded state and the suspended state.

[0045] It should be further explained that, see [link / reference] Figure 3 and Figure 5 The inner side of the first wheel frame is defined as the side located below in the suspended state. The inner side of the first wheel frame has an upwardly protruding avoidance part 311, which is located near the long connecting rod. This avoidance part allows the wheel to avoid the lower tray when switching to the suspended state. For details, see [link to details]. Figure 5After the forks are in position on the pallet, the load wheel assembly 30 is located at the first gap on the pallet, allowing the load wheel to move downwards through the first gap until it contacts the ground. In this embodiment, a clearance portion is provided to increase the distance between the first wheel carrier and the edge of the first gap, preventing interference between the first wheel carrier and the bottom of the pallet during the switching between the loaded and suspended states. Furthermore, in the loaded state, the first wheel carrier tilts from back to front to increase the distance to the edge of the first gap.

[0046] like Figure 4-5 As shown, the linkage locking mechanism 50 is used to lock the load wheel assembly 30 in a suspended state during the entry or exit of the fork 22 into or out of the pallet 10. The linkage locking mechanism 50 ensures that the load wheel 32 is suspended during the entry and exit of the fork 22 into the pallet 10, and does not obstruct the switching of the load wheel assembly 30 to the load-bearing state after the fork 22 has entered or exited its designated position. The operational relationship between the load wheel assembly 30, the linkage mechanism 40, and the fork mechanism 20 in this embodiment is described, for example, in publications CN117658023A or CN118723873A.

[0047] The linkage locking mechanism 50 includes a limiting member 51 and a limiting seat 52. The limiting member 51 is fixed to the swing arm 41, and one end of the limiting member 51 extends into the first space 521 of the limiting seat 52. The limiting member 51 moves with the swing arm 41 within the first space 521 of the limiting seat 52. When the load wheel 32 is suspended, the limiting member 51 abuts against the first side of the first space 521, and the limiting member 51 has a tendency to continue moving towards the first side. The abutment design between the limiting member 51 and the limiting seat 52 forms a mechanical self-locking mechanism, preventing the load wheel 32 from accidentally falling when entering or exiting the tray 10. When the load wheel 32 is suspended, the limiting member 51 has a tendency to continue moving towards the first side, preventing the load wheel 32 from falling under its own weight. The locking structure is simple and reliable. In one specific embodiment, the extension of the pivot shaft of the swing arm 41 is directly used as the limiting member 51. The limiting seat 52 includes an upper pressure plate and a lower pressure plate, and the space between the upper pressure plate and the lower pressure plate is the first space 521. When the load wheel assembly 30 is suspended, the limiting member 51 abuts against the upper pressure plate from below and has a tendency to continue moving upward, thereby achieving mechanical self-locking and locking the state of the load wheel assembly 30. In other specific embodiments, a limiting hole is formed on the limiting seat 52. The shape of the limiting hole matches the movement path of the limiting member 51 within it, so that the corresponding function can also be achieved by cooperating with the limiting member 51 through the limiting hole.

[0048] The cooperation structure between the pallet loading / unloading mechanism and pallet 10

[0049] The guide wheel assembly 24 includes multiple lifting guide wheels 242, which are guided along a stepped inclined surface. In a preferred embodiment, the guide wheel assembly 24 includes a second wheel frame 241, through which the multiple lifting guide wheels 242 are mounted on the forks 22. Mounting via the second wheel frame 241 reduces installation complexity. The multiple lifting guide wheels 242 are divided into two groups, each group mounted on opposite sides of the second wheel frame 241 and staggered. The staggered guide wheel groups expand the contact coverage with the pallet 10, accommodating crossbeams 11 of different sizes; they also prevent single-sided guide wheel failure when the forks 22 are tilted, improving fault tolerance.

[0050] The load wheel 32, in a suspended state, is located at the front of the fork plate transition section 222, with its bottom protruding downwards from the fork plate transition section 222. The fork plate transition section 222 is equipped with a roller assembly 23, the bottom of which protrudes beyond the bottom of the fork plate transition section 222. The roller assembly 23 is positioned slightly below the bottom of the fork plate transition section 222 and is not jammed by the pallet bottom crossbeam 11. Preferably, the roller assembly 23 is located in the middle or rear of the fork plate transition section 222, thereby cooperating with the load wheel 32 to support the front of the fork 22. Through the cooperation of the guide wheel assembly 24, the load wheel 32, and the roller assembly 23, the static friction of the fork 22 during the process of entering and exiting the pallet 10 is converted into rolling friction, allowing it to smoothly enter and exit the pallet 10 at low speeds.

[0051] Taking the process of entering pallet 10 as an example, such as Figure 6-7 As shown, during the entry of the fork 22, when it passes the bottom step of the pallet 10, the guide wheel assembly 24 guides and lifts the fork 22. During entry, the guide wheel assembly 24 first enters the pallet 10, followed by the load wheel 32, and then the roller assembly 23. This ensures that the fork 22 always maintains contact with the bottom of the pallet 10 with minimal friction (rolling friction). It is important to emphasize that the key to this solution is the shape of the guide wheel assembly 24 and the fork plate transition section 222, and the cooperation between the load wheel 32 and the guide wheel assembly 24 to reduce the friction between the fork 22 and the pallet 10 when entering and exiting. This achieves a purely mechanical structure without an independent power source, adapting to the uniform and low-speed movement characteristics of AGVs and other transport vehicles entering and exiting the pallet 10.

[0052] With the above settings, the pallet in / out mechanism experiences rolling friction with the pallet when entering and exiting the pallet, which is less than the static friction between the pallet and the ground. As a result, the pallet can remain in its original position during the process of the forks entering and exiting the pallet, and the forks will not cause the pallet to move. This ensures that the AGV vehicle can accurately judge the position when controlling the forks to enter and exit the pallet.

[0053] In this embodiment, the roller assembly 23 is a wear-resistant roller, preferably comprising a pair of symmetrically arranged wear-resistant rollers. In this embodiment, the roller assembly 23 is directly mounted at the hinge point between the first wheel frame 31 and the linkage mechanism 40. The roller assembly 23 is directly positioned at the force-bearing hinge point, eliminating the need for an additional mounting structure, resulting in a simple structure.

[0054] It should be noted that the pallet loading and unloading mechanism of this embodiment is also applicable to other pallets with crossbeams at the bottom, such as grid pallets, and is not limited to American pallets.

[0055] Transport robots

[0056] The handling robot includes a frame, on which a fork mechanism 20 is slidably and vertically mounted. The fork mechanism 20 is driven to move up and down by a lifting drive device. In this embodiment, the handling robot is an AGV forklift, capable of automatically controlling vehicle movement and fork lifting 22 without manual operation. When it moves near the pallet 10, it maintains a constant, low speed to control the forks 22 to enter and exit the pallet 10, and there is a need to handle empty pallets 10. This embodiment of the handling robot includes the aforementioned pallet entry / exit mechanism, suitable for US standard pallets 10. Since the pallet entry / exit mechanism uses a purely mechanical structure to allow the forks 22 to smoothly enter and exit the US standard pallet 10, when used with an AGV forklift, no modification to its control method is required, simplifying the modification of existing vehicles.

Claims

1. A transport robot, comprising, Frame, The fork mechanism, which is slidably and liftingly mounted on the vehicle frame, includes the fork carriage and the forks mounted on the fork carriage; The load wheel assembly includes a first wheel frame and a load wheel mounted on the first wheel frame. The load wheel assembly is driven by a linkage mechanism to switch between a loaded state and a suspended state. Its features are, The front of the fork is divided into the fork tip and the fork plate transition section. The fork tip is located at the very front of the fork, and its bottom surface is higher than the bottom surface of the fork plate transition section. The connection between the fork tip and the fork plate transition section is a beveled transition. The bottom of the fork plate transition section is a flat straight structure, which is used to guide the contact between the bottom of the fork and the pallet. The bottom surface of the fork plate transition section is the lowest point of the fork, and the connection between the fork plate transition section and the rear of the fork is a beveled transition. It also includes a linkage locking mechanism for locking the load wheel assembly in a suspended state during the entry or exit of the forks from the pallet.

2. The handling robot according to claim 1, characterized in that, A guide wheel assembly is provided at the junction of the fork tip and the fork plate transition section.

3. A handling robot according to claim 1, characterized in that, The load wheel in the suspended state is located at the front of the fork plate transition section, and its bottom protrudes downward from the fork plate transition section; a roller assembly is provided in the middle or rear of the fork plate transition section, and the bottom of the roller assembly protrudes from the bottom of the fork plate transition section.

4. A handling robot according to claim 1, characterized in that, The length of the forklift transition section is greater than the width of the widest gap between adjacent crossbeams of the matched pallet.

5. A handling robot according to claim 1, characterized in that, The inner side of the first wheel frame is provided with an upwardly protruding avoidance part, which is located near the long connecting rod; after the forks enter the pallet, the load wheel assembly 30 is located at the first gap on the pallet. During the process of switching from the suspended state to the load-bearing state, there is always a gap between the first wheel frame and the edge of the first gap.

6. A handling robot according to claim 1, characterized in that, The linkage locking mechanism includes a limiting member and a limiting seat. The linkage mechanism includes a swing arm and a long swing arm. The limiting member is fixed on the swing arm, and one end of the limiting member extends into the first space of the limiting seat. The limiting member moves with the swing arm within the first space of the limiting seat. When the load wheel is suspended, the limiting member abuts against the first side of the first space, and the limiting member has a tendency to continue moving towards the first side.

7. A handling robot according to claim 3, characterized in that, The first wheel carrier of the load wheel is connected to the fork at a first hinge point, and the first wheel carrier is hinged to the linkage mechanism at a second hinge point. The roller assembly is located at the second hinge point.

8. A handling robot according to claim 2, characterized in that, The guide wheel assembly includes multiple lifting guide wheels, which are guided along the stepped inclined surface.

9. A handling robot according to claim 8, characterized in that, The guide wheel assembly includes a second wheel carrier, and multiple lifting guide wheels are mounted on the forks via the same second wheel carrier.

10. A handling robot according to claim 9, characterized in that, The multiple lifting guide wheels are divided into two groups, and the two groups of lifting guide wheels are installed on both sides of the second wheel frame and staggered.

Images