Bypass type lifting equipment safety protector based on oil pressure damping

Abstract

The invention discloses an oil resistance bypass safety protector, and relates to the technical field of safety equipment. The oil cylinder comprises an oil cylinder shell, a piston, a connecting rod and a crankshaft, an integral cavity formed by a piston chamber and a crankshaft chamber which are communicated is arranged in the shell, and the cavity is filled with hydraulic oil. The key point is that a damping oil hole and a switch for adjusting the size of the damping oil hole are arranged on the piston and / or the cylinder cover. When equipment stalls, the transmission shaft drives the crankshaft to rotate at a high speed, the piston is forced to reciprocate, oil can only flow through a narrow damping oil hole, huge resistance is generated, the resistance is converted into braking torque, and the equipment slowly descends at a constant speed. The through-flow area can be changed by adjusting the switch, so that the descending speed is accurately controlled. The hydraulic damper works completely depending on hydraulic damping, is resistant to water and oil, extremely high in reliability, simple in structure, capable of achieving stepless speed regulation and suitable for various occasions such as elevators, lifters and fire-fighting slow descending equipment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mechanical safety equipment, in particular to an oil resistance bypass safety protector for elevators, lifts, aerial work platforms and the like.

[0002] BACKGROUND At present, the safety protection device of high-altitude equipment such as elevators and lifts is of great importance, and its performance is directly related to life safety. The safety protection devices commonly used in the prior art mostly rely on centrifugal friction speed limiter or pure mechanical gear reducer.

[0003] The centrifugal friction speed limiter relies on the centrifugal force to increase the friction between the friction block and the friction wall to achieve braking. However, this device has obvious defects: when water or oil enters the device, the friction coefficient will decrease sharply, resulting in insufficient friction and complete failure, causing a major accident of free falling. In addition, the braking speed of such devices is usually not adjustable or very inconvenient to adjust.

[0004] The gear reducer is reliable, but its structure is complex, the manufacturing cost is high, it is easy to wear, and it also has the problem of difficult speed adjustment.

[0005] Therefore, there is an urgent need in the art for a safety protection device with simple structure, stable and reliable performance, not affected by the environment (oil, water), and capable of conveniently achieving stepless speed adjustment.

[0006] Cannot dynamically adjust speed.

[0007] SUMMARY The present application aims to overcome the shortcomings of the prior art and provide an oil resistance bypass safety protector. The core purpose is to provide stable resistance through the principle of hydraulic damping to ensure uniform slow descent when the lifting equipment loses speed, and the resistance can be conveniently adjusted.

[0008] To achieve the above purpose, the present application adopts the following technical solutions: An oil resistance bypass safety protector includes a cylinder housing, a piston, a connecting rod, and a crankshaft. The inside of the cylinder housing constitutes a continuous whole chamber, including a piston chamber and a crankshaft chamber. The piston slides in the piston chamber and is connected to the crankshaft through the connecting rod. The crankshaft is used to link with the external transmission shaft. The whole chamber is filled with hydraulic oil. The key is that a damping oil hole is opened on the piston and / or cylinder cover to form a damping oil way, and an adjusting switch for adjusting the flow area is arranged on the oil way.

[0009] The operating principle is as follows: When the lifting equipment is operating normally, the drive shaft drives the crankshaft to rotate at a constant speed. If the equipment stalls (e.g., due to brake failure), the drive shaft attempts to accelerate under the influence of gravity, thereby accelerating the crankshaft and forcing the piston to reciprocate rapidly within the cylinder. Because the chamber is filled with hydraulic oil and can only flow through the narrow damping oil passage, significant fluid resistance is generated (this resistance is proportional to the square of the flow rate and inversely proportional to the flow area of ​​the oil hole). This resistance reacts on the crankshaft, ultimately converting into a huge rotational damping torque on the drive shaft, effectively suppressing its acceleration and allowing the equipment to descend at a constant and safe speed. By adjusting the size of the damping oil hole by adjusting the switch, the descent speed can be precisely controlled.

[0010] The beneficial effects of the present invention are: 1. **Extremely high reliability**: All moving parts are immersed in oil, ensuring ample lubrication and minimal wear. The damping force is derived from the inherent properties of the oil and is completely unaffected by environmental factors such as water and oil intrusion, fundamentally eliminating the risk of frictional failure.

[0011] 2. **Stepless speed regulation**: The descent speed can be easily and continuously changed by adjusting the switch, and even real-time dynamic speed regulation can be performed during the operation of the equipment, making adjustment and operation convenient.

[0012] 3. **Simple structure**: The core components are only the cylinder, piston, connecting rod and crankshaft, with a compact structure and low manufacturing and maintenance costs.

[0013] 4. **Wide Application**: It can be used not only in elevators and lifts, but also in high-altitude firefighting descent equipment, aircraft carrier arresting cable systems, and any other applications requiring stable linear resistance.

[0014] **Brief Description** Figure 1 The figure is a schematic diagram of the structural principle of an embodiment of the oil resistance bypass safety protector of the present invention.

[0015] **Description of the numbers in the figure**: 1-Cylinder housing, 101-Piston chamber, 102-Crankshaft chamber, 2-Piston, 3-Connecting rod, 4-Crankshaft, 5-Oil filling hole, 6-Oil drain hole, 7-Damper oil hole, 8-Adjusting switch, 9-Cylinder head, 10-High-pressure oil pipe, 11-Mounting bracket.

[0016] **Specific implementation** The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0017] like Figure 1As shown, the oil resistance bypass safety protector provided by the present invention has a cylinder housing 1 which is a sealed container, and inside it are a piston chamber 101 and a crankshaft chamber 102 which are connected. The piston 2 slides in the piston chamber 101 and is connected to the crankshaft 4 through a connecting rod 3. The output end of the crankshaft 4 is used to connect to the transmission shaft of the lifting equipment (not shown in the figure). The cylinder head 9 is fixed to both ends of the cylinder housing 1 by bolts. A damping oil hole 7 is machined on the upper cylinder head 9, and a needle valve type regulating switch 8 is screwed into the oil hole. The flow area of ​​the oil channel is changed by screwing it in and out.

[0018] Before work, fill the entire chamber with clean hydraulic oil through the oil filling hole 5 and exhaust the air. When the lifting equipment is working normally, the power system drives the transmission shaft, and the transmission shaft drives the crankshaft 4 to rotate smoothly, and the piston 2 performs reciprocating motion. At this time, the damping force generated by the oil flow is within the design allowable range. When the equipment loses control and falls freely, the transmission shaft is accelerated by gravity, driving the crankshaft 4 to rotate at high speed, and the piston 2 moves at high speed to try to press the oil from one chamber to another. Since the oil can only flow through the tiny damping oil hole 7 restricted by the adjustment switch 8, a huge pressure drop will be generated, forming a strong damping force. This force is ultimately manifested as a torque that prevents the transmission shaft from rotating through the connecting rod 3 and the crankshaft 4, thereby causing the equipment to descend at a uniform and slow speed.

[0019] **Example 2**: In another embodiment, the damping oil hole 7 can be directly opened on the piston 2. **Example 3**: For scenarios requiring greater heat dissipation or more flexible layout, the oil port on the cylinder head 9 can be connected through an external high-pressure oil pipe 10, and the regulating switch 8 (such as a throttle valve) can be installed on this high-pressure oil pipe 10 to form an external damping oil circuit.

[0020] The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention.

[0021] The crankshaft cover in the figure is designed to facilitate the removal of the crankshaft and is fixed to the cylinder block by screws. It is not related to the principle and will not be explained in detail.

Claims

1. An oil resistance bypass safety protector, characterized in that: include: The oil cylinder housing (1) has an interior forming a connected integral chamber, the integral chamber including a piston chamber (101) and a crank chamber (102); a piston (2) slidably arranged in the piston chamber (101); a connecting rod (3) having one end hinged to the piston (2); a crankshaft (4) arranged in the crankshaft chamber (102) and hinged to the other end of the connecting rod (3), the crankshaft (4) being used to connect to an external transmission shaft; an oil filling hole (5) for filling oil into the integral chamber and an oil discharge hole (6) for discharging oil are provided on the oil cylinder housing (1); at least one damping oil hole (7) is opened on the end cylinder cover of the piston (2) and / or the piston chamber (101), the damping oil hole (7) forming a damping oil channel connecting the cavities on both sides of the piston (2); and a regulating switch (8) for adjusting the flow cross-sectional area thereof is provided on the damping oil channel.

2. The oil resistance bypass safety protector according to claim 1, characterized in that: The regulating switch (8) is a needle valve, a throttle valve or a proportional valve.

3. The oil resistance bypass safety protector according to claim 1 or 2, characterized in that: The damping oil hole (7) is opened on the cylinder cover (9) at the end of the piston chamber (101), and the regulating switch (8) is mounted on the cylinder cover (9) and connected to the damping oil hole (7).

4. The oil resistance bypass safety protector according to claim 3, characterized in that: The damping oil passage is an external oil circuit formed by a high-pressure oil pipe (10), one end of which is connected to the oil port of the cavity at one end of the piston chamber (101), and the other end is connected to the oil port of the cavity at the other end of the piston chamber (101) or the crank chamber (102). The regulating switch (8) is installed on the high-pressure oil pipe (10).

5. The oil resistance bypass safety protector according to claim 1, characterized in that: It also includes a mounting bracket (11), on which the oil cylinder housing (1) and the power system for driving the transmission shaft are fixed.

6. A lifting device, comprising a transmission mechanism and a safety protection device, characterized in that: The safety protection device is an oil resistance bypass safety protector as claimed in any one of claims 1 to 5, wherein the crankshaft (4) of the oil resistance bypass safety protector is connected to the transmission shaft of the transmission mechanism.

7. Use of the oil resistance bypass safety protector according to any one of claims 1 to 5 in high-altitude firefighting descent equipment or aircraft carrier arresting cable systems.

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