Pit hole system for shear fork lifting platform and using method of pit hole system

Abstract

The invention discloses a pit hole system for a scissor lifting platform. The pit hole system comprises a flow distributing and collecting valve, a first double-acting oil cylinder, a pit hole protection oil cylinder, a second double-acting oil cylinder, a cross overflow valve set and a main reversing valve. The flow distributing and collecting valve is located between the main reversing valve and the double-cylinder rodless cavity. The first double-acting oil cylinder and the second double-acting oil cylinder are arranged in parallel, and cylinder bodies are connected with the protection plate through mechanical connecting rods. The crossed overflow valve group is bridged with a bidirectional overflow valve between rodless cavity oil ways of the two cylinders; one end of the pit hole protection oil cylinder is connected with the frame, the other end of the pit hole protection oil cylinder is connected with the pit hole vertical plate, and the pit hole vertical plate rotates around the rotating hinge point. The invention further discloses a using method of the pit system. The problem that in the prior art, due to uneven load pressure, double oil cylinders move asynchronously is solved; the load difference is automatically compensated, the service life of a hydraulic element is prolonged, it is ensured that the pit protection mechanism rapidly and stably acts, and the platform is prevented from overturning due to ground collapse.

Description

Technical Field

[0001] The present invention relates to the field of lifting equipment, and in particular to a pit system for a scissor lift platform and a method of using the same. Background Art

[0002] Scissor-type mobile lift work platforms are a type of lifting equipment commonly used in warehouses, logistics, construction sites, and other locations. They utilize a hydraulic system to drive the lifting mechanism. Platform stability is crucial during operation, and the pit system is crucial for ensuring this stability. However, existing pit systems often utilize a simple, parallel, dual-cylinder oil supply system without a synchronous control mechanism. This leads to asynchronous movement of the two cylinders, causing the platform to tilt. Furthermore, heavy loads on one cylinder can accelerate damage to the cylinder seals, posing a safety hazard for large scissor-type mobile lift work platforms.

[0003] Therefore, it is necessary to develop a new type of pit system for scissor lift platforms to solve the problem of asynchronous movement of the two cylinders due to uneven load pressure in the existing technology. Summary of the Invention

[0004] Purpose of the invention: In view of the shortcomings and defects of the existing technology, the present invention provides a pothole system for a scissors lift platform and a method of using the same, so as to solve the problem in the existing technology of asynchronous movement of the dual cylinders due to uneven load pressure; automatically compensate for load differences, extend the service life of hydraulic components, ensure fast and stable operation of the pothole protection mechanism, and avoid overturning of the platform due to ground collapse.

[0005] Technical solution: A pothole system for a scissors lift platform of the present invention is characterized in that it includes a diverter and collector valve, a double-acting oil cylinder 1, a pothole protection oil cylinder, a double-acting oil cylinder 2, a cross-over relief valve group, and a main reversing valve; the diverter and collector valve is located between the main reversing valve and the double-cylinder rodless cavity; the double-acting oil cylinder 1 and the double-acting oil cylinder 2 are arranged in parallel, and the cylinder body is connected to the protective plate through a mechanical connecting rod; the cross-over relief valve group bridges the two-way relief valve between the oil circuits of the two cylinder rodless cavities; one end of the pothole protection oil cylinder is connected to the frame, and the other end of the pothole protection oil cylinder is connected to the pothole vertical plate, and the pothole vertical plate rotates around the rotating hinge.

[0006] Wherein, the flow diversion and collection valve is connected to an external oil tank.

[0007] Wherein, the flow diverter and collector valve is connected to an external hydraulic pump.

[0008] Wherein, the hydraulic pump is located on the pump station of the scissor lift platform.

[0009] Wherein, the double-acting oil cylinder 1 and the double-acting oil cylinder 2 are provided with piston rods.

[0010] The method for using the pothole system for a scissor lift platform of the present invention is characterized by comprising the following steps: 1) system initialization and preparation; 2) pothole detection and extension of the protective plate; 3) locking of the protective plate and platform operation; and 4) completion of the operation and retraction of the protective plate.

[0011] Among them, the step 1) system initialization and preparation: after moving the scissor lift platform to the working area, check whether the hydraulic pump, diverter and collector valve, cross-relief valve group, main reversing valve, double-acting cylinder 1, double-acting cylinder 2 and pothole protection cylinder are firmly connected to ensure that there is no oil leakage or looseness; start the hydraulic pump to put it into working state, and the oil output by the hydraulic pump is transported to the diverter and collector valve through the pipeline. At this time, the system is in standby state.

[0012] Among them, the step 2) pothole detection and extension of the protective plate: when the platform is running, the controller sends a signal to the main reversing valve, and the main reversing valve switches to the extension position; the oil output by the hydraulic pump is forced to be equally divided by the diverter and collector valve, and respectively delivered to the rodless chambers of double-acting cylinder one and double-acting cylinder two; since the cylinder bodies of double-acting cylinder one and double-acting cylinder two are connected to the protective plate through a mechanical connecting rod, the double-cylinder piston rods are pushed out synchronously, driving the protective plate to quickly cover the pothole area; in the process of extending the protective plate, if the double-acting cylinder on one side is blocked due to the bulge of the ground, resulting in an increase in the oil pressure on that side, when the pressure difference exceeds the pressure difference threshold set by the cross-relief valve group, the cross-relief valve group opens, and the oil on the high-pressure side overflows to the low-pressure side, realizing dynamic compensation of the load pressure, ensuring synchronous movement of the cylinders on both sides, and avoiding pressure overload damage to the hydraulic components.

[0013] Among them, the step 3) protective plate locking and platform operation: when the protective plate completely covers the pothole and reaches the predetermined position, the double balancing valve automatically locks the rod chamber oil circuit of the double-acting cylinder 1 and the double-acting cylinder 2, so that the protective plate maintains rigid support and provides a stable operating foundation for the scissors lift platform; the operator can use the scissors lift platform normally for cargo handling and high-altitude operations, and the pothole protection cylinder maintains the current state to ensure the stability of the pothole stand and prevent the platform from overturning due to pothole problems.

[0014] Among them, the step 4) ends the operation and retracts the protective plate: when the scissors lift platform completes the operation and needs to evacuate the current area, the operator sends a retraction command to the main reversing valve, and the main reversing valve switches to the retracted position; oil enters the rod chamber of the double-acting cylinder one and the double-acting cylinder two, and the oil in the rodless chamber is returned to the oil tank after being collected by the diverter and collector valve. Under the action of oil pressure, the double-cylinder piston rods retract synchronously, driving the protective plate to retract synchronously; during the retraction process, the double balancing valve provides stable back pressure for the rodless chamber to ensure smooth retraction; at the same time, the pothole protection cylinder performs corresponding telescopic adjustments according to the movement state of the platform, so that the pothole vertical plate is reset around the rotation hinge, facilitating the smooth evacuation of the platform.

[0015] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0016] The present invention has high synchronization accuracy (mechanical forced diversion): a diverter and collector valve is added to the dual-cylinder parallel oil circuit, and the flow is forced to be equally divided through a mechanical structure (no reliance on electronic sensors). The present invention has shock resistance and pressure balance (dynamic compensation): a cross-over overflow valve group is connected across the dual-cylinder rodless chamber oil circuit. When the pressure on one side exceeds the limit (such as ground impact), the high-pressure oil automatically overflows to the low-pressure side, achieving load pressure adaptation. The present invention has fast response and reliability (pure mechanical control): the diverter and collector valve and the balancing valve are both mechanical structures, without the need for electronic closed-loop control, and the anti-pollution ability is significantly better than that of the electro-hydraulic proportional valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of a prior art pothole system;

[0018] Figure 2 is a schematic diagram of the pothole system of the present invention;

[0019] Figure 3 It is a structural schematic diagram of the present invention;

[0020] In the figure, 1 is the diverter and collector valve; 2 is the double-acting cylinder 1; 3 is the pothole protection cylinder; 4 is the double-acting cylinder 2; 5 is the cross-over relief valve group; 6 is the main reversing valve; 7 is the frame; 8 is the pothole vertical plate; and 9 is the rotation hinge. DETAILED DESCRIPTION

[0021] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific implementation methods.

[0022] The pit system for the scissor lift platform of the present invention includes a diverter and collector valve 1, a double-acting oil cylinder 2, a pothole protection oil cylinder 3, a double-acting oil cylinder 2 4, a cross-over relief valve group 5, and a main reversing valve 6; the diverter and collector valve 1 is located between the main reversing valve 6 and the double-cylinder rodless cavity; the double-acting oil cylinder 1 2 and the double-acting oil cylinder 2 4 are arranged in parallel, and the cylinder body is connected to the protective plate through a mechanical connecting rod; the cross-over relief valve group 5 bridges the two-way relief valve between the oil circuits of the two cylinder rodless cavities; one end of the pothole protection oil cylinder 3 is connected to the frame 7, and the other end of the pothole protection oil cylinder 3 is connected to the pothole vertical plate 8, and the pothole vertical plate 8 rotates around the rotation hinge 9.

[0023] The flow-dividing and collecting valve 1 of the present invention is connected to an external oil tank. The flow-dividing and collecting valve 1 is connected to an external hydraulic pump. The hydraulic pump is located on the pump station of the scissor lift platform. Double-acting cylinders 1 and 2 are equipped with piston rods.

[0024] The method for using the pit system for a scissor lift platform of the present invention comprises the following steps:

[0025] 1) System initialization and preparation: After moving the scissor lift platform to the working area, check whether the connections of the hydraulic pump, diverter and collector valve 1, cross relief valve group 5, main reversing valve 6, double-acting cylinder 1 2, double-acting cylinder 2 4 and pothole protection cylinder 3 are stable to ensure there is no oil leakage or looseness; start the hydraulic pump to put it into working state, and the oil output by the hydraulic pump is transported to the diverter and collector valve 1 through the pipeline. At this time, the system is in standby state.

[0026] 2) Pothole detection and extension of protective plate: When the platform is running, the controller sends a signal to the main reversing valve 6, and the main reversing valve 6 switches to the extended position; the oil output by the hydraulic pump is forced to be equally divided by the diverter and collector valve 1, and respectively delivered to the rodless chambers of the double-acting cylinder 1 2 and the double-acting cylinder 2 4; since the cylinder bodies of the double-acting cylinder 1 2 and the double-acting cylinder 2 4 are connected to the protective plate through a mechanical connecting rod, the piston rods of the two cylinders are pushed out synchronously, driving the protective plate to quickly cover the pothole area; during the extension of the protective plate, if the double-acting cylinder on one side is blocked due to the bulge of the ground, resulting in an increase in the oil pressure on that side, when the pressure difference exceeds the pressure difference threshold set by the cross-relief valve group 5, the cross-relief valve group 5 opens, and the oil on the high-pressure side overflows to the low-pressure side, realizing dynamic compensation of the load pressure, ensuring the synchronous movement of the cylinders on both sides, and avoiding pressure overload damage to the hydraulic components.

[0027] 3) Protective plate locking and platform operation: When the protective plate completely covers the pothole and reaches the predetermined position, the double balancing valve automatically locks the rod chamber oil circuit of double-acting cylinder 1 2 and double-acting cylinder 2 4, so that the protective plate maintains rigid support and provides a stable operating foundation for the scissor lift platform; the operator can use the scissor lift platform normally for cargo handling and high-altitude operations, and the pothole protection cylinder 3 maintains the current state to ensure the stability of the pothole stand and prevent the platform from overturning due to pothole problems.

[0028] 4) End of operation and retraction of protective plate: When the scissor lift platform completes the operation and needs to evacuate the current area, the operator sends a retraction command to the main reversing valve 6, and the main reversing valve 6 switches to the retracted position; oil enters the rod chamber of the double-acting cylinder 1 2 and the double-acting cylinder 2 4, and the oil in the rodless chamber is collected by the diverter and collector valve 1 and returned to the oil tank. Under the action of oil pressure, the piston rods of the two cylinders retract synchronously, driving the protective plate to retract synchronously; during the retraction process, the double balancing valve provides stable back pressure for the rodless chamber to ensure smooth retraction; at the same time, the pothole protection cylinder 3 performs corresponding telescopic adjustment according to the movement state of the platform, so that the pothole vertical plate 8 is reset around the rotation hinge 9, which facilitates the smooth evacuation of the platform.

[0029] The diverter and collector valve of the present invention has forced flow distribution. The diverter and collector valve is arranged between the main reversing valve and the double-cylinder rodless cavity. When the oil cylinder is extended, the flow is forced to be equally divided, and the output flow of the pump station is forced to be equally divided into the double-cylinder rodless cavity, eliminating the "load-sensitive deviation" of the parallel oil circuit. Double-acting oil cylinder: two cylinders are connected in parallel, and the cylinder body is rigidly connected to the protective plate through a mechanical connecting rod to ensure physical synchronization constraint. One end of the pothole protection oil cylinder is connected to the frame, and the other end is connected to the pothole vertical plate. Through the extension and contraction of the oil cylinder, the pothole vertical plate rotates 90 degrees clockwise around the rotating hinge to achieve the protection function.

[0030] The present invention adopts an anti-shock pressure compensation design and a cross-over relief valve group: a two-way relief valve is connected across the oil circuits of the two cylinder rodless chambers to set a pressure difference threshold. When the pressure difference exceeds the standard due to a single-side ground impact, the oil on the high-pressure side overflows to the low-pressure side to balance the load pressure; a double balancing valve allows rapid oil inflow when extended, provides back pressure when retracted, and locks the cylinder position in an emergency.

[0031] The protective plate of the present invention is extended quickly. After detecting the pothole signal, the main reversing valve is switched to the extended position, and the hydraulic pump outputs oil that is equally divided into the double-cylinder rodless chamber through the diverter and collector valve; the double-cylinder piston rods are pushed out synchronously to drive the protective plate to cover the pothole; if one side is blocked from touching the ground (such as a bulge on the ground), the oil pressure on that side increases, the cross-relief valve group opens, and the oil is diverted to the opposite side to avoid pressure overload.

[0032] Guard plate locking and retraction: After being extended into position, the dual balancing valves close the rod chamber oil circuit, and the guard plate maintains rigid support; when the platform moves out of the pit area, the main reversing valve switches to the retracted position, oil enters the rod chamber of the dual cylinders, and the oil in the rodless chamber is collected and returned to the oil tank through the diverter and collector valve, and the guard plate retracts synchronously.

[0033] The present invention has high synchronization accuracy (mechanical forced diversion): a diverter and collector valve is added to the dual-cylinder parallel oil circuit, and the flow is forced to be equally divided through a mechanical structure (no reliance on electronic sensors). The present invention has shock resistance and pressure balance (dynamic compensation): a cross-over overflow valve group is connected across the dual-cylinder rodless chamber oil circuit. When the pressure on one side exceeds the limit (such as ground impact), the high-pressure oil automatically overflows to the low-pressure side, achieving load pressure adaptation. The present invention has fast response and reliability (pure mechanical control): the diverter and collector valve and the balancing valve are both mechanical structures, without the need for electronic closed-loop control, and the anti-pollution ability is significantly better than that of the electro-hydraulic proportional valve.

Claims

1. A pit system for a scissor lift platform, characterized by: The utility model comprises a flow-dividing and collecting valve (1), a double-acting oil cylinder (2), a pothole protection oil cylinder (3), a double-acting oil cylinder (4), a cross-over relief valve group (5), and a main reversing valve (6); the flow-dividing and collecting valve (1) is located between the main reversing valve (6) and the double-cylinder rodless cavity; the double-acting oil cylinder (2) and the double-acting oil cylinder (4) are arranged in parallel, and the cylinder bodies are connected to the protective plate through a mechanical connecting rod; the cross-over relief valve group (5) bridges the two-way relief valve between the oil circuits of the two cylinder rodless cavities; one end of the pothole protection oil cylinder (3) is connected to the vehicle frame (7), and the other end of the pothole protection oil cylinder (3) is connected to the pothole vertical plate (8), and the pothole vertical plate (8) rotates around the rotation hinge (9).

2. The pit system for a scissor lift platform according to claim 1, characterized in that: The flow dividing and collecting valve (1) is connected to an external oil tank.

3. The pit system for a scissor lift platform according to claim 2, characterized in that: The flow dividing and collecting valve (1) is connected to an external hydraulic pump.

4. The pit system for a scissor lift platform according to claim 3, characterized in that: The hydraulic pump is located on the pump station of the scissor lift platform.

5. The pit system for a scissor lift platform according to claim 1, characterized in that: The double-acting oil cylinder 1 (2) and the double-acting oil cylinder 2 (4) are provided with piston rods.

6. The method for using the pit system for the scissor lift platform is characterized by: The process includes the following steps: 1) system initialization and preparation; 2) pothole detection and guard plate extension; 3) guard plate locking and platform operation; and 4) operation completion and guard plate retraction.

7. The method for using the pit system for a scissor lift platform according to claim 6, characterized in that: The step 1) system initialization and preparation: after moving the scissor lift platform to the working area, check whether the hydraulic pump, the diverter and collector valve (1), the cross overflow valve group (5), the main reversing valve (6), the double-acting oil cylinder 1 (2), the double-acting oil cylinder 2 (4) and the pothole protection oil cylinder (3) are firmly connected to ensure that there is no oil leakage or looseness; start the hydraulic pump to put it into working state, and the oil output by the hydraulic pump is transported to the diverter and collector valve (1) through the pipeline. At this time, the system is in standby state.

8. The method for using the pit system for a scissor lift platform according to claim 6, characterized in that: The step 2) pothole detection and extension of the protective plate: when the platform is running, the controller sends a signal to the main reversing valve (6), and the main reversing valve (6) switches to the extension position; the oil output by the hydraulic pump is forced to be equally divided by the diversion and collection valve (1) and respectively delivered to the rodless chambers of the double-acting oil cylinder one (2) and the double-acting oil cylinder two (4); since the cylinder bodies of the double-acting oil cylinder one (2) and the double-acting oil cylinder two (4) are connected to the protective plate through a mechanical connecting rod, the double-cylinder piston rods are pushed out synchronously, driving the protective plate to quickly cover the pothole area; during the extension of the protective plate, if the double-acting oil cylinder on one side is blocked due to the ground bulge, resulting in an increase in the oil pressure on that side, when the pressure difference exceeds the pressure difference threshold set by the cross-overflow valve (5) group, the cross-overflow valve group (5) opens, and the oil on the high-pressure side overflows to the low-pressure side, realizing dynamic compensation of the load pressure, ensuring synchronous movement of the oil cylinders on both sides, and avoiding pressure overload damage to the hydraulic components.

9. The method for using the pit system for a scissor lift platform according to claim 6, characterized in that: The step 3) locking of the protective plate and platform operation: when the protective plate completely covers the pothole and reaches the predetermined position, the double balancing valve automatically locks the rod chamber oil circuit of the double-acting cylinder 1 (2) and the double-acting cylinder 2 (4), so that the protective plate maintains a rigid support and provides a stable operating foundation for the scissor lift platform; the operator can use the scissor lift platform normally for cargo handling and high-altitude operations, and the pothole protection cylinder (3) maintains the current state to ensure the stability of the pothole stand and prevent the platform from overturning due to the pothole problem.

10. The method for using the pit system for a scissor lift platform according to claim 6, characterized in that: The step 4) ends the operation and retracts the protective plate: when the scissor lift platform completes the operation and needs to evacuate the current area, the operator sends a retraction command to the main reversing valve (6), and the main reversing valve (6) switches to the retracted position; oil enters the rod chamber of the double-acting oil cylinder 1 (2) and the double-acting oil cylinder 2 (4), and the oil in the rodless chamber is collected by the diverter and collector valve (1) and returned to the oil tank. Under the action of oil pressure, the double-cylinder piston rods retract synchronously, driving the protective plate to retract synchronously; during the retraction process, the double balance valve provides a stable back pressure for the rodless chamber to ensure a smooth retraction action; at the same time, the pit protection oil cylinder (3) is adjusted accordingly according to the movement state of the platform, so that the pit vertical plate (8) is reset around the rotation hinge (9), facilitating the smooth evacuation of the platform.

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