A multi-stage fork structure

Abstract

This utility model relates to the field of forklift technology, specifically to a multi-stage forklift structure, including a first fork, a second fork disposed on the upper side of the first fork, and a third fork disposed on the upper side of the second fork. A first screw is rotatably disposed on the first fork; the first screwlift is threadedly connected to a first connecting block. A power component drives the first screwlift to rotate, causing the first connecting block to extend and retract the second fork. Simultaneously, the second forklift's displacement is driven by a drive mechanism to extend and retract the third fork. This avoids transmission deviations caused by rope stretching and deformation, and replaces the ropelift's flexible transmission with rigid transmission, completely avoiding the risks of rope stretching, fatigue, and instantaneous overload breakage after long-term use. It solves the technical problems of increased transmission clearance due to rope stretching and deformation after long-term use of multi-stage forks, the lack of overload protection during boom extension and retraction, and the ropelift's susceptibility to breakage due to excessive instantaneous tension.

Description

Technical Field

[0001] This utility model relates to the field of forklift technology, specifically to a multi-stage forklift structure. Background Technology

[0002] Multistage forks are a fork design used in logistics, warehousing, and forklift equipment. They are typically used in scenarios requiring multi-level or multi-stage material handling, enabling the retrieval, handling, and placement of goods on high shelves. Multistage forks allow for multi-level lifting and transfer of goods, making forklifts or other transport equipment work more efficiently in narrow or elevated environments. Multistage forks are usually used in conjunction with electric forklifts, stackers, or stacker cranes, and are driven by hydraulic, pneumatic, or electric systems. The lifting and extension of the forks are adjusted by an operating controller to meet different work requirements.

[0003] Chinese Patent Publication No. CN222042588 discloses a multi-stage fork structure, relating to the field of forklift equipment. The multi-stage fork structure includes a support frame, a fixed arm assembly, a telescopic arm assembly, and a telescopic linkage mechanism. The telescopic linkage mechanism includes a first linkage component and a second linkage component. The first linkage component includes a first rope and a first pulley. The second linkage component includes a second rope and a second pulley. By combining the first rope, first pulley, second rope, and second pulley with each fixed arm assembly and arm, not only can the extension of the three arms be achieved, but the first and second ropes also significantly reduce the space occupied compared to the traditional belt transmission method, allowing for a reduction in fork height. Furthermore, the structure is simpler, the operation is more stable, and the storage capacity of the rack bins is increased.

[0004] The aforementioned patent proposes that the multi-stage fork achieves equidistant extension and retraction of the three arms through four sets of ropes and pulley assemblies. However, since the ropes rely solely on a fixed adjustment assembly for unidirectional tension adjustment, long-term use can easily lead to increased transmission clearance due to rope stretching and deformation, causing asynchronous extension and retraction of the arms. Furthermore, it lacks overload protection during the extension and retraction process, and the ropes are prone to breakage due to excessive instantaneous tension when the arms are obstructed. Therefore, we propose a multi-stage fork structure. Utility Model Content

[0005] To address the aforementioned issues, a multi-stage fork structure is provided. A power component drives a first screw to rotate, causing a first connecting block to extend and retract the second fork. Simultaneously, the second fork's displacement is driven by a drive mechanism to extend and retract the third fork. This avoids transmission deviations caused by rope stretching and deformation. Furthermore, rigid transmission replaces the rope's flexible transmission, completely eliminating the risks of rope stretching, fatigue, and instantaneous overload breakage after long-term use. This solves the technical problems of increased transmission clearance due to rope stretching and deformation after long-term use in multi-stage forks, the lack of overload protection during boom extension and retraction, and the rope's susceptibility to breakage due to excessive instantaneous tension.

[0006] To address the problems of existing technologies, this utility model provides a multi-stage fork structure, including a first fork, a second fork disposed on the upper side of the first fork, a third fork disposed on the upper side of the second fork, and a first screw rotatably disposed on the first fork; the first screw is threadedly connected to a first connecting block, which is fixedly connected to the second fork; a power component is fixedly mounted on the outer side of the first fork, the output end of which is fixedly connected to one end of the first screw, and the power component is used to provide power for the rotation of the first screw; a drive mechanism is provided between the second and third forks to drive the third fork to move synchronously.

[0007] Preferably, a first guide seat is fixedly connected to the outer side of the first connecting block, and a first guide rail is fixedly connected to the side of the first fork near the first guide seat, with the first guide seat and the first guide rail slidingly engaged.

[0008] Preferably, the drive mechanism includes a displacement component, a gear transmission component, and a guide component; the displacement component is disposed between the second fork and the third fork, and is used to support the third fork to achieve displacement; the gear transmission component is disposed between the second fork and the displacement component, and is used to transmit the displacement power of the second fork to the displacement component; the guide component is disposed between the second fork and the displacement component, and is used to assist the third fork in achieving linear movement.

[0009] Preferably, the displacement assembly includes a second screw and a second connecting block; the second screw is rotatably mounted on the second fork; the second connecting block is threadedly connected to the second screw, and the second connecting block is fixedly connected to the third fork.

[0010] Preferably, the guide assembly includes a second guide seat and a second guide rail; the second guide seat is fixedly connected to the second connecting block; the second guide rail is fixedly connected to the side of the second fork near the second guide seat, and the second guide rail and the second guide seat are slidably engaged.

[0011] Preferably, the gear transmission assembly includes a gear disc and a toothed plate; the gear disc is rotatably mounted on the second fork; the toothed plate is fixedly connected to the third fork and meshes with the gear disc.

[0012] Preferably, a bevel gear assembly is rotatably provided on the side of the third fork near the toothed disc, the working end of the bevel gear assembly is fixedly connected to the shaft of the toothed disc, and the working end of the bevel gear assembly away from the toothed disc is fixedly connected to the second screw.

[0013] The advantages of this utility model compared to the prior art are:

[0014] 1. The first screw is driven to rotate by a power component, which causes the first connecting block to drive the second fork to extend and retract. At the same time as the second fork moves, the third fork is simultaneously driven to extend and retract via a drive mechanism. This avoids transmission deviation caused by rope stretching and deformation. Furthermore, it replaces the rope's flexible transmission with rigid transmission, completely avoiding the risk of rope stretching, fatigue, and instantaneous overload breakage after long-term use. This solves the technical problems of increased transmission clearance due to rope stretching and deformation after long-term use of multi-stage forks, lack of overload protection during boom extension and retraction, and rope breakage due to excessive instantaneous tension.

[0015] 2. The linear displacement power of the second fork is transmitted to the second screw through the gear transmission assembly, causing the second screw to rotate, thereby driving the third fork to extend and retract synchronously. This completes the precise transmission and motion conversion of power from the second fork to the third fork, solving the technical problems of complex power transmission paths and easy power loss or directional deviation in flexible transmission in multi-stage forks. Attached Figure Description

[0016] Figure 1 This utility model application presents a three-dimensional schematic diagram of the first and second forks of a multi-stage fork structure.

[0017] Figure 2 This utility model application presents a three-dimensional schematic diagram of the third fork and the power component of a multi-stage fork structure.

[0018] Figure 3 This is a three-dimensional schematic diagram of the second screw and the second guide rail of a multi-stage fork structure according to this utility model application.

[0019] Figure 4 yes Figure 2 Enlarged diagram of point A in the middle.

[0020] Figure 5 yes Figure 2 Enlarged diagram of point B in the middle.

[0021] Figure 6 yes Figure 3 Enlarged diagram of point C in the middle.

[0022] The numbers in the diagram are as follows: 1. First fork; 11. Second fork; 12. Third fork; 2. First screw; 21. First connecting block; 22. Power component; 23. First guide seat; 24. First guide rail; 25. Second screw; 26. Second connecting block; 27. Gear plate; 28. Gear plate; 29. ​​Bevel gear assembly; 210. Second guide seat; 211. Second guide rail. Detailed Implementation

[0023] To further understand the features, technical means, and specific objectives and functions achieved by this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and specific embodiments.

[0024] See Figures 1-4 As shown, a multi-stage fork structure includes a first fork 1, a second fork 11 disposed on the upper side of the first fork 1, and a third fork 12 disposed on the upper side of the second fork 11. A first screw 2 is rotatably disposed on the first fork 1. A first connecting block 21 is threadedly connected to the first screw 2, and the first connecting block 21 is fixedly connected to the second fork 11. A power component 22 is fixedly installed on the outer side of the first fork 1, and the output end of the power component 22 is fixedly connected to one end of the first screw 2. The power component 22 is used to provide power for the rotation of the first screw 2. A drive mechanism for driving the third fork 12 to move synchronously is disposed between the second fork 11 and the third fork 12. A first guide seat 23 is fixedly connected to the outer side of the first connecting block 21, and a first guide rail 24 is fixedly connected to the side of the first fork 1 near the first guide seat 23. The first guide seat 23 and the first guide rail 24 are in sliding engagement.

[0025] Specifically, the power component 22 is preferably a brake motor. The first guide seat 23 and the first guide rail 24 form a sliding guide pair.

[0026] When the multi-stage forks are engaged, the power unit 22 is activated, and the output end of the power unit 22 drives the first screw 2 to rotate around its axis. Relying on the sliding guide pair formed by the first guide seat 23 and the first guide rail 24, the circumferential rotational freedom of the first connecting block 21 is restricted, so that the first connecting block 21 moves stably along the axis of the first screw 2; simultaneously, the first guide seat 23 slides along the first guide rail 24, thereby driving the second fork 11 to achieve smooth extension and retraction.

[0027] During the displacement of the second fork 11, power is transmitted to the third fork 12 through the drive mechanism, driving the third fork 12 to extend along the upper side of the second fork 11, and the third fork 12 and the second fork 11 move in the same direction. The extension and retraction of the second fork 11 is driven by the threaded engagement of the first screw 2. Utilizing the technical characteristics of the screw drive with a fixed lead and small transmission clearance, transmission deviation caused by the stretching deformation of the rope is effectively avoided. At the same time, the drive mechanism realizes the direct synchronous drive of the second fork 11 to the third fork 12, with a clear power transmission path and no energy loss caused by elastic deformation.

[0028] Furthermore, by replacing the flexible transmission of the rope with the rigid transmission of the first screw 2, problems such as stretching, fatigue aging, and instantaneous overload breakage of the rope after long-term use will not occur. The mechanical structure formed by the screw and the drive mechanism has better load-bearing performance and can withstand the instantaneous load generated when the boom is obstructed. It breaks through the strength limitations of flexible components and significantly improves the service life and operational stability of multi-stage forks in heavy-duty and high-frequency operation scenarios.

[0029] See Figures 2-6As shown, the drive mechanism includes a displacement assembly, a gear transmission assembly, and a guide assembly. The displacement assembly is disposed between the second fork 11 and the third fork 12, and is used to support the third fork 12 in achieving displacement. The gear transmission assembly is disposed between the second fork 11 and the displacement assembly, and is used to transmit the displacement power of the second fork 11 to the displacement assembly. The guide assembly is disposed between the second fork 11 and the displacement assembly, and is used to assist the third fork 12 in achieving linear movement. The displacement assembly includes a second screw 25 and a second connecting block 26. The second screw 25 is rotatably disposed on the second fork 11. The second connecting block 26 is threadedly connected to the second screw 25 and is fixedly connected to the third fork 12. The guide assembly includes a second guide seat 210 and a second guide rail 211. The second guide seat 210 is fixedly connected to the second connecting block 26. The second guide rail 211 is fixedly connected to the side of the second fork 11 near the second guide seat 210, and the second guide rail 211 and the second guide seat 210 are in sliding engagement.

[0030] Specifically, the second guide seat 210 and the second guide rail 211 form a sliding guide pair.

[0031] During the displacement of the second fork 11, the linear displacement power of the second fork 11 is transmitted to the second screw 25 through the gear transmission assembly, driving the second screw 25 to rotate around the axis. Relying on the sliding guide pair formed by the second guide seat 210 and the second guide rail 211, the circumferential rotational freedom of the second connecting block 26 is restricted, preventing the second connecting block 26 from rotating synchronously with the second screw 25.

[0032] Since the second screw 25 and the second connecting block 26 are connected by a threaded engagement, the rotational motion of the second screw 25 is converted into the linear motion of the second connecting block 26 along the screw axis, thereby driving the third fork 12 to extend and retract. The third fork 12 extends along the upper side of the second fork 11. Through the coordinated cooperation of the gear transmission assembly and the threaded transmission, the extension and retraction of the second fork 11 and the third fork 12 are ensured to be synchronized, achieving efficient conversion of power transmission and consistent motion coordination.

[0033] See Figures 4-6 As shown, the gear transmission assembly includes a gear disc 27 and a toothed plate 28; the gear disc 27 is rotatably mounted on the second fork 11; the toothed plate 28 is fixedly connected to the third fork 12, and the toothed plate 28 meshes with the gear disc 27; a bevel gear assembly 29 is rotatably mounted on the side of the third fork 12 near the gear disc 27, the working end of the bevel gear assembly 29 is fixedly connected to the shaft of the gear disc 27, and the working end of the bevel gear assembly 29 away from the gear disc 27 is fixedly connected to the second screw 25.

[0034] Specifically, the bevel gear assembly 29 consists of two sets of meshing bevel gears. The bevel gear on one side of the bevel gear assembly 29 is fixedly connected to the shaft of the gear disk 27, and the bevel gear on the bevel gear assembly 29 away from the gear disk 27 is fixedly connected to the second screw 25.

[0035] During the displacement of the second fork 11, the toothed disc 27 is synchronously driven to move along the toothed plate 28. Through the meshing of the toothed disc 27 and the toothed plate 28, the toothed disc 27 generates rotational motion under the constraint of the tooth surface of the toothed plate 28, which in turn drives the bevel gear on one side of the bevel gear assembly 29, which is fixedly connected to the shaft of the toothed disc 27, to rotate synchronously.

[0036] The bevel gear assembly 29 consists of two sets of meshing bevel gears, with the bevel gear furthest from the gear disc 27 fixedly connected to the second screw 25. Based on the meshing transmission relationship between the bevel gears, the rotational power of the gear disc 27 is transmitted to the second screw 25 through the bevel gear assembly 29, driving the second screw 25 to rotate around its axis. The rotational motion of the second screw 25 is further converted into the linear motion of the second connecting block 26, ultimately driving the third fork 12 to extend and retract, completing the precise transmission and motion conversion of power from the second fork 11 to the third fork 12.

[0037] Working principle: When the multi-stage forks are put into operation, the power unit 22 is activated. The output end of the power unit 22 drives the first screw 2 to rotate, which causes the first connecting block 21 to drive the second fork 11 to achieve telescopic movement. During the displacement of the second fork 11, the toothed disc 27 moves along the toothed plate 28. The rotational power of the toothed disc 27 is transmitted to the second screw 25 through the bevel tooth assembly 29. The rotational motion of the second screw 25 is further converted into the linear motion of the second connecting block 26, which ultimately drives the third fork 12 to achieve telescopic movement.

[0038] The above embodiments only illustrate one or more implementations of this utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this utility model. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the appended claims.

Claims

1. A multi-stage fork structure, comprising a first fork (1), a second fork (11) disposed on the upper side of the first fork (1), and a third fork (12) disposed on the upper side of the second fork (11), characterized in that, A first screw (2) is rotatably mounted on the first fork (1); The first screw (2) is threadedly connected to a first connecting block (21), and the first connecting block (21) is fixedly connected to the second fork (11); A power component (22) is fixedly installed on the outside of the first fork (1). The output end of the power component (22) is fixedly connected to one end of the first screw (2). The power component (22) is used to provide power for the rotation of the first screw (2). A drive mechanism for synchronously displacing the third fork (12) is provided between the second fork (11) and the third fork (12).

2. The multi-stage fork structure according to claim 1, characterized in that, The first connecting block (21) is fixedly connected to the outer side of the first guide seat (23), and the first fork (1) is fixedly connected to the side of the first guide seat (23) with the first guide rail (24) in sliding fit.

3. The multi-stage fork structure according to claim 1, characterized in that, The drive mechanism includes a displacement assembly, a gear transmission assembly, and a guide assembly; The displacement component is disposed between the second fork (11) and the third fork (12), and the displacement component is used to support the third fork (12) to achieve displacement; The gear transmission assembly is disposed between the second fork (11) and the displacement assembly. The gear transmission assembly is used to transmit the displacement power of the second fork (11) to the displacement assembly. The guide assembly is located between the second fork (11) and the displacement assembly, and the guide assembly is used to assist the third fork (12) in achieving linear movement.

4. A multi-stage fork structure according to claim 3, characterized in that, The displacement assembly includes a second screw (25) and a second connecting block (26); The second screw (25) is rotatably mounted on the second fork (11); The second connecting block (26) is threadedly connected to the second screw (25), and the second connecting block (26) is fixedly connected to the third fork (12).

5. A multi-stage fork structure according to claim 3, characterized in that, The guiding assembly includes a second guide seat (210) and a second guide rail (211); The second guide seat (210) is fixedly connected to the second connecting block (26); The second guide rail (211) is fixedly connected to the side of the second fork (11) near the second guide seat (210), and the second guide rail (211) and the second guide seat (210) are in sliding engagement.

6. A multi-stage fork structure according to claim 3, characterized in that, The gear transmission assembly includes a gear disc (27) and a gear plate (28); The toothed disc (27) is rotatably mounted on the second fork (11); The toothed plate (28) is fixedly connected to the third fork (12), and the toothed plate (28) meshes with the toothed disc (27).

7. A multi-stage fork structure according to claim 4, characterized in that, The third fork (12) is rotatably provided with a bevel gear assembly (29) on the side near the toothed disc (27). The working end of the bevel gear assembly (29) is fixedly connected to the shaft of the toothed disc (27), and the working end of the bevel gear assembly (29) away from the toothed disc (27) is fixedly connected to the second screw (25).

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