Forklift truck push-off lifting device
By installing adjustable slider assemblies in the basic boom and multi-stage boom of the forklift, and utilizing the cooperation of auxiliary cylinders, ratchet and pawl assemblies, and sequence valves, automatic compensation and locking of the sliders are achieved, solving the problem of increased clearance caused by slider wear and improving the operating accuracy and safety of the forklift.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG HUAHE FORKELEVATOR
- Filing Date
- 2026-04-30
- Publication Date
- 2026-05-29
AI Technical Summary
Under heavy loads and high-frequency operations, the slider of the existing forklift telescopic boom wears down, causing the gap between boom segments to increase, which affects the alignment accuracy and operational safety of the telescopic boom.
Adjustable slider assemblies are installed in the basic boom and multi-stage boom of the forklift. Through the cooperation of auxiliary cylinders, ratchet and pawl assemblies and sequence valves, the sliders can automatically compensate and lock, filling the gaps caused by wear.
It effectively extends the service life of the slider, improves the operating accuracy and safety of the telescopic boom, and ensures the stability and reliability of the forklift.
Smart Images
Figure CN122102032A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to forklift technology, and in particular to a forklift unloading and lifting device. Background Technology
[0002] Forklifts are lifting and transporting machines widely used in mining, ports, construction, and other fields. Their telescopic boom mechanism is the core component for lifting and long-distance material delivery. A typical telescopic boom consists of a base boom and multiple telescopic boom sections, including secondary and tertiary booms. To ensure smooth telescopic movement and guiding accuracy between boom sections, and to avoid severe wear caused by direct contact between the steel boom sections, existing technologies commonly install sliders in the gaps between the boom sections. These sliders are typically made of softer materials than the boom material, such as wear-resistant nylon or copper alloy. They are fixedly installed on the inner wall of the front end of the base boom and the outer wall of the rear end of the secondary boom, filling the gaps between the boom sections to provide support, guidance, and reduce friction.
[0003] However, in practical applications, especially under heavy-load and high-frequency operating conditions, the existing slider structure has the following main technical problems: as a sacrificial filler, the slider will inevitably wear during long-term telescopic sliding. As wear intensifies, the gap between the originally precisely filled boom sections gradually increases, causing unexpected vertical or lateral swaying of the telescopic boom in the extended state, which seriously affects the positioning accuracy of the forklift for heavy objects and the operational safety. Summary of the Invention
[0004] In view of this, the present invention addresses the deficiencies of the prior art, and its main objective is to provide a forklift unloading and lifting device that solves the aforementioned problems.
[0005] To achieve the above objectives, the present invention adopts the following technical solution: a forklift unloading and lifting device, installed on the vehicle body, the unloading and lifting device includes a basic arm rotatably connected to the vehicle body, and a telescopic multi-stage arm inserted into the basic arm, and adjustable slider assemblies are respectively provided inside the basic arm and the multi-stage arm. The basic arm is equipped with a main hydraulic cylinder, and the basic arm and the multi-stage arm are equipped with auxiliary cylinders respectively. The output shaft of the auxiliary cylinder is connected to the slider assembly. The main hydraulic cylinder and the auxiliary cylinder share the same oil circuit, and a sequence valve is installed on the connection path between the auxiliary cylinder and the oil circuit.
[0006] Furthermore, the output shaft of the auxiliary cylinder is equipped with ratchet teeth, and the inner cavities of the basic arm and the multi-stage arm are equipped with pawl assemblies that mesh with the ratchet teeth.
[0007] Furthermore, the slider assembly includes a slider, a disc spring, and a pusher connected in sequence, with one side of the pusher connected to the pawl assembly, and the output shaft of the auxiliary cylinder connected to the slider.
[0008] Furthermore, the slider includes a first plate and a second plate, a disc spring is disposed between the first plate and the second plate, and one end of the pusher is connected to the first plate.
[0009] Furthermore, the pawl assembly includes a connecting seat and a pawl rotatably connected to the connecting seat, with teeth at the tail of the pawl.
[0010] Furthermore, the pusher includes a first rod and a second rod that are inserted into each other. The second rod is connected to the first rod. An opening is provided on one side of the first rod, and a rack connected to the second rod is slidably connected inside the opening. The rack meshes with the teeth.
[0011] Furthermore, the pusher is located between the auxiliary cylinder and the connecting seat.
[0012] Furthermore, the teeth are multiple and located on the side of the pawl.
[0013] Furthermore, the multi-stage arm includes at least a first arm body and a second arm body; the auxiliary cylinder includes a first cylinder body disposed within the basic arm and a second cylinder body disposed within the first arm body; a slider assembly is respectively disposed within the basic arm and the first arm body.
[0014] Furthermore, the oil circuit includes a main line, a first branch line, and a second branch line; the main line is connected to the main oil cylinder, the first branch line is connected to the first cylinder body, and the second branch line is connected to the second cylinder body, and the second branch line is a telescopic pipe.
[0015] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, as can be seen from the above technical solution, by setting adjustable slider assemblies connected to auxiliary cylinders inside the basic arm and the multi-stage arm respectively, when the slider wears out due to long-term use, the auxiliary cylinder can push the slider assembly to extend outward and actively fill the increased fitting gap.
[0016] To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description
[0017] Figure 1 This is a perspective view of Embodiment 1 of the present invention.
[0018] Figure 2 This is a top view of the basic arm of Embodiment 1 of the present invention.
[0019] Figure 3 This is Embodiment 1 of the present invention. Figure 2 Enlarged view of point A.
[0020] Figure 4 This is Embodiment 1 of the present invention. Figure 3 Enlarged view of point B.
[0021] Figure 5 This is a perspective view of the pusher component according to Embodiment 1 of the present invention.
[0022] Explanation of reference numerals in the attached diagram: Vehicle body 10; Basic arm 20, main hydraulic cylinder 21; Multi-stage arm 30, first arm body 31, second arm body 32; Slider assembly 40, slider 41, first plate 411, second plate 412, disc spring 42, pusher 43, first rod 431, second rod 432, opening 433, rack 434; Auxiliary cylinder 50, ratchet 51, first cylinder block 52, second cylinder block 53; Oil line 60, main line 61, first branch line 62, second branch line 63; Sequence valve 70; Pawl assembly 80, connector 81, pawl 82, teeth 83. Detailed Implementation
[0023] Please refer to Figure 1-5 As shown, it illustrates the specific structure of a preferred first embodiment of the present invention, which is a forklift unloading and lifting device installed on the vehicle body 10. The unloading and lifting device includes a basic arm 20 rotatably connected to the vehicle body 10, and a telescopic multi-stage arm 30 inserted into the basic arm 20. The basic arm 20 and the multi-stage arm 30 are respectively provided with adjustable slider assemblies 40 inside. The basic arm 20 is equipped with a main hydraulic cylinder 21, and both the basic arm 20 and the multi-stage arm 30 are equipped with auxiliary cylinders 50. The output shaft of the auxiliary cylinder 50 is connected to the slider assembly 40. The main hydraulic cylinder 21 and the auxiliary cylinder 50 share the same oil circuit 60, and a sequence valve 70 is installed on the connection path between the auxiliary cylinder 50 and the oil circuit 60. By setting adjustable slider assemblies 40 connected to the auxiliary cylinders 50 inside the basic arm 20 and the multi-stage arm 30, when the slider wears out due to long-term use, the auxiliary cylinder 50 can push the slider assembly 40 outward to actively fill the increased fit clearance.
[0024] For example, the output shaft of the auxiliary cylinder 50 is provided with a ratchet 51, and the inner cavities of the basic arm 20 and the multi-stage arm 30 are provided with pawl assemblies 80 that mesh with the ratchet 51. By providing a ratchet 51 on the output shaft of the auxiliary cylinder 50 and providing pawl assemblies 80 that mesh with the ratchet 51 in the inner cavities of the basic arm 20 and the multi-stage arm 30, when the auxiliary cylinder 50 extends to push the slider assembly 40 to press against the wall surface of the arm body, the pawl assembly 80 and the ratchet 51 form a locking engagement, so that the slider in the slider assembly 40 fills the gap, thereby protecting the basic arm 20 and the multi-stage arm 30.
[0025] For example, the slider assembly 40 includes a slider 41, a disc spring 42, and a pusher 43 connected in sequence. One side of the pusher 43 is connected to the pawl assembly 80, and the output shaft of the auxiliary cylinder 50 is connected to the slider 41. In forklift unloading and lifting operations, the boom system often bears large impact loads (such as the reaction force when unloading goods or the instantaneous pulling force when lifting heavy objects). The disc spring 42 can play a buffering and energy-absorbing role, converting the impact load into the elastic deformation of the disc spring 42, reducing the direct damage of the impact to the slider 41, the auxiliary cylinder 50, and the pawl assembly 80, and extending the service life of each component. At the same time, when the auxiliary cylinder 50 pushes the slider 41 to move, the auxiliary cylinder 50 pushes the slider 41 to press against the wall of the arm body, so that the disc spring 42 is compressed and the pusher 43 drives the pawl assembly 80 to move, so that the pawl assembly 80 and the ratchet 51 on the output shaft of the auxiliary cylinder 50 are engaged.
[0026] For example, the slider 41 includes a first plate 411 and a second plate 412, a disc spring 42 is disposed between the first plate 411 and the second plate 412, and one end of the pusher 43 is connected to the first plate 411. When the first plate 411 moves toward the wall of the arm under the drive of the auxiliary cylinder 50, the first plate 411 drives the pusher 43 to move together. At this time, the pawl assembly 80 and the ratchet 51 are in a disengaged state. When the first plate 411 moves toward the second plate 412, the pawl assembly 80 and the ratchet 51 are in a engaged state.
[0027] For example, the pawl assembly 80 includes a connecting seat 81 and a pawl 82 rotatably connected to the connecting seat 81, with teeth 83 at the tail of the pawl 82. When the contact surface of the first plate 411 wears down due to long-term use, the thickness (or relative position) of the first plate 411 changes. Under the elastic thrust of the disc spring 42, the first plate 411 automatically moves towards the wall of the arm (i.e., away from the second plate 412) to fill the gap caused by wear. At the same time, since the first plate 411 drives the pusher 43 to move together, the reverse movement of the pusher 43 causes the pawl 82 to automatically separate from the ratchet teeth 51, releasing the locking state.
[0028] For example, the pusher 43 includes a first rod 431 and a second rod 432 that are inserted into each other. The second rod 432 is connected to the first rod 431. An opening 433 is provided on one side of the first rod 431. A rack 434 connected to the second rod 432 is slidably connected in the opening 433. The rack 434 meshes with the teeth 83. When the first plate 411 wears, the disc spring 42 pushes the first plate 411 to move towards the wall of the arm. The second rod 432 moves with the first plate 411. Since the pusher 43 is located between the auxiliary cylinder 50 and the connecting seat 81, and the pusher 43 is linked with the pawl assembly 80, when the second rod 432 moves with the first plate 411, the pusher 43 drives the pawl 82 to rotate away from the ratchet 51, so that the pawl 82 automatically separates from the ratchet 51.
[0029] It should be noted that when the rack 434 slides in the opening 433, the linear motion of the rack 434 is converted into the rotational motion of the teeth 83, thereby driving the pawl 82 to rotate around the connecting seat 81, so that the pawl 82 engages or disengages with the ratchet 51 on the output shaft of the auxiliary cylinder 50.
[0030] For example, the pusher 43 is located between the auxiliary cylinder 50 and the connecting seat 81. The pusher 43 is located between the auxiliary cylinder 50 and the connecting seat 81 such that the locking action is triggered only when the first plate 411 is pressed, and the locking mechanism is automatically released when the auxiliary cylinder 50 retracts or the disc spring 42 pushes the first plate 411 outward (in the release direction).
[0031] The teeth 83 are multiple and located on the side of the pawl 82.
[0032] For example, the multi-stage boom 30 includes at least a first boom body 31 and a second boom body 32; the auxiliary cylinder 50 includes a first cylinder body 52 disposed within the basic boom 20 and a second cylinder body 53 disposed within the first boom body 31; a slider assembly 40 is respectively disposed within the basic boom 20 and the first boom body 31. The auxiliary cylinder 50 includes a first cylinder body 52 disposed within the basic boom 20 and a second cylinder body 53 disposed within the first boom body 31, meaning that each boom segment is equipped with an independent auxiliary cylinder 50, and the slider assembly 40 of each boom segment can be independently driven by the corresponding auxiliary cylinder 50. This achieves independent control of the gap compensation between boom segments at each stage, avoiding the compensation failure problem caused by uneven wear at each stage.
[0033] For example, the oil circuit 60 includes a main line 61, a first branch line 62, and a second branch line 63. The main line 61 is connected to the main cylinder 21, the first branch line 62 is connected to the first cylinder body 52, and the second branch line 63 is connected to the second cylinder body 53. The second branch line 63 is a telescopic pipe. The telescopic pipe design allows the second branch line 63 to automatically extend or shorten with the extension and retraction of the first boom body 31, ensuring that the second cylinder body 53 remains connected to the main line 61 throughout the entire stroke of the boom, achieving continuous and reliable oil supply.
[0034] In summary, the key design focus of this invention is; 1.1 Hydraulic oil enters the main cylinder 21 via the main line 61, pushing the multi-stage boom 30 outward. At this time, because the set pressure of the sequence valve 70 is higher than the working pressure of the main cylinder, the oil cannot enter the auxiliary cylinder 50. The auxiliary cylinder maintains its initial position, the slider assembly 40 maintains a normal fit clearance with the boom wall, the main cylinder 21 returns oil, the multi-stage boom retracts, and the auxiliary cylinder still does not move. 1.2 When the slider 41 wears down due to long-term use, resulting in an increased clearance, the system pressure rises to the opening pressure of the sequence valve 70. Hydraulic oil enters the auxiliary cylinder 50, and the output shaft of the auxiliary cylinder extends, directly pushing the slider 41 towards the wall of the arm body to actively fill the increased clearance. After the slider 41 contacts the wall, the auxiliary cylinder continues to push, compressing the disc spring 42 and converting the thrust into elastic deformation to avoid rigid impact. At the same time, the pusher 43 moves with the first plate 411, driving the pawl assembly 80 to engage with the ratchet 51 on the output shaft of the auxiliary cylinder, forming a mechanical lock and maintaining the slider in a pressed state. 1.3 When the slider 41 wears out again, the disc spring 42 releases its elastic force and automatically pushes the first plate 411 toward the wall of the arm to fill the newly generated gap. The first plate 411 drives the second rod 432 in the pusher 43 to move, so that the rack 434 slides in the opening 433, driving the pawl 82 to rotate in the opposite direction around the connecting seat 81, so that the pawl 82 and the ratchet 51 automatically separate and release the lock. At this time, the auxiliary cylinder 50 can extend again to push the slider to further compensate for the gap and re-establish the lock, realizing multiple automatic gap compensation cycles.
[0035] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.
Claims
1. A forklift unloading and lifting device, installed on the vehicle body (10), characterized in that: The unloading and lifting device includes a basic arm (20) rotatably connected to the vehicle body (10), and a telescopic multi-stage arm (30) inserted into the basic arm (20). The basic arm (20) and the multi-stage arm (30) are respectively provided with adjustable slider assemblies (40). The basic arm (20) is provided with a main oil cylinder (21), and the basic arm (20) and the multi-stage arm (30) are respectively provided with auxiliary cylinders (50). The output shaft of the auxiliary cylinder (50) is connected to the slider assembly (40). The main oil cylinder (21) and the auxiliary cylinder (50) share the same oil circuit (60), and a sequence valve (70) is installed on the connection path between the auxiliary cylinder (50) and the oil circuit (60).
2. The forklift unloading and lifting device according to claim 1, characterized in that: The output shaft of the auxiliary cylinder (50) is provided with a ratchet (51), and the inner cavity of the basic arm (20) and the multi-stage arm (30) is provided with a pawl assembly (80) that meshes with the ratchet (51).
3. The forklift unloading and lifting device according to claim 2, characterized in that: The slider assembly (40) includes a slider (41), a disc spring (42) and a pusher (43) connected in sequence. One side of the pusher (43) is connected to the pawl assembly (80), and the output shaft of the auxiliary cylinder (50) is connected to the slider (41).
4. A forklift unloading and lifting device according to claim 3, characterized in that: The slider (41) includes a first plate (411) and a second plate (412), the disc spring (42) is disposed between the first plate (411) and the second plate (412), and one end of the pusher (43) is connected to the first plate (411).
5. A forklift unloading and lifting device according to claim 4, characterized in that: The pawl assembly (80) includes a connecting seat (81) and a pawl (82) rotatably connected to the connecting seat (81), the tail of the pawl (82) being provided with teeth (83).
6. A forklift unloading and lifting device according to claim 5, characterized in that: The pusher (43) includes a first rod (431) and a second rod (432) that are inserted into each other. The second rod (432) is connected to the first plate (411). An opening (433) is provided on one side of the first rod (431). A rack (434) connected to the second rod (432) is slidably connected in the opening (433). The rack (434) meshes with teeth (83).
7. A forklift unloading and lifting device according to claim 5 or 6, characterized in that: The pusher (43) is located between the auxiliary cylinder (50) and the connecting seat (81).
8. A forklift unloading and lifting device according to claim 7, characterized in that: The teeth (83) are multiple and located on the side of the pawl (82).
9. A forklift unloading and lifting device according to claim 7, characterized in that: The multi-stage arm (30) includes at least a first arm body (31) and a second arm body (32); the auxiliary cylinder (50) includes a first cylinder body (52) disposed in the basic arm (20) and a second cylinder body (53) disposed in the first arm body (31); the slider assembly (40) is respectively disposed in the basic arm (20) and the first arm body (31).
10. A forklift unloading and lifting device according to claim 9, characterized in that: The oil circuit (60) includes a main line (61), a first branch line (62) and a second branch line (63); the main line (61) is connected to the main oil cylinder (21), the first branch line (62) is connected to the first cylinder body (52), the second branch line (63) is connected to the second cylinder body (53), and the second branch line (63) is a telescopic pipe.