An electric lift with over-impact protection function

Abstract

This utility model discloses an electric lift with overshoot protection function, belonging to the technical field of electric lifts. This electric lift with overshoot protection function includes a rope pulley assembly, a load-bearing connection mechanism, a drive assembly, an electrical control system, a housing, a rope, and a battery assembly. The rope pulley assembly is externally equipped with a rope pulley cover. Inside the rope pulley cover are a rope pulley, an inlet guide pulley, an outlet guide pulley, and a rope separator. The upper end of the rope is suspended from a high point via a figure-eight knot. The rope enters the rope pulley between the inlet guide pulley and the rope pulley, and then exits the rope pulley between the rope pulley and the outlet guide pulley. A load-bearing connection mechanism is located below the rope pulley assembly. The rope, the rope pulley assembly, and the load-bearing connection mechanism are all on the same vertical line of gravity.

Description

Technical Field

[0001] This utility model relates to the field of electric lifting device technology, specifically an electric lifting device with over-impact protection function. Background Technology

[0002] The danger of falling while working at height is well known. Work at height can be performed in various situations, including wind power maintenance, hydropower maintenance, power grid installation and maintenance, and fire fighting.

[0003] When working at height, electric lifts are used for ascent and descent. Currently, a more popular method is to use drones to set up anchor points on reliable structures at high altitudes and suspend working ropes. One end of the rope is tied to the anchor point using a figure-eight knot, which requires a much thicker rope than the rope itself.

[0004] Existing electric lifts on the market lack upper limit alarms and shutdown mechanisms when ascending along the rope. If the load is the operator, operator negligence could cause the figure-eight knot at the end of the rope to get stuck in the rope pulley assembly. This could result in minor damage to the electric lift, rendering it inoperable, or even more serious damage such as the rope breaking through the pulley, causing the electric lift and the connected operator to fall. Without insurance, this could result in fatal impact, while with insurance, the electric lift could still injure the operator. Similarly, if the load is an object and the operator uses a remote control from the ground, it's difficult for the operator to observe the relative positions of the electric lift and the rope. This could also lead to the figure-eight knot at the end of the rope getting stuck in the rope pulley, causing minor damage to the electric lift, rendering it inoperable, or more serious damage such as the rope breaking through the pulley, causing the electric lift and the object to fall to the ground. Summary of the Invention

[0005] To address the problem of ropes getting stuck and overshooting during the ascent of an electric lift, this invention provides an electric lift with an overshoot protection function.

[0006] In view of the above problems, the technical solution proposed by this utility model is as follows: An electric hoist with overshoot protection function includes a rope pulley assembly, a load-bearing connection mechanism, a drive assembly, an electrical control system, a housing, a rope, and a battery assembly. The rope pulley assembly is provided with a rope pulley cover. Inside the rope pulley cover are a rope pulley, a rope inlet guide pulley, a rope outlet guide pulley, and a rope separator. The upper end of the rope is suspended from a high suspension point by a figure-eight knot. The rope enters the rope pulley between the rope inlet guide pulley and the rope pulley. The rope passes around the rope pulley and exits the rope pulley between the rope pulley and the rope outlet guide pulley. A load-bearing connection mechanism is provided below the rope pulley assembly. The rope, the rope pulley assembly, and the load-bearing connection mechanism are on the same vertical line of gravity.

[0007] The power transmission direction is: motor -> electromagnetic brake -> reducer -> external rope pulley. The rope pulley pulls the rope to realize the up and down movement of the electric lift. The encoder is located at the end of the motor and coaxial with the motor shaft. It detects the motor speed and direction and transmits the signal to the electronic control system. The electromagnetic brake is located between the motor and the reducer. When the electric lift needs to be stopped, the motor shuts off and the electromagnetic brake de-energizes to prevent the electric lift from falling due to gravity.

[0008] The internal electrical control system of the electric lift includes a control section, a drive section, and a current detection section. The control section issues run and stop commands based on the status of the external adjustment handle, sends information to the drive section, and the drive section drives the motor to run. The current detection section detects the motor current and transmits this information to the control board. Furthermore, the drive section adopts a speed mode for motor control. The control section instructs the drive section to drive the motor to follow the target speed given by the speed adjustment handle.

[0009] The electric lift's internal control system includes control software that controls the motor based on operator information (direction, speed, etc.), load size, real-time battery capacity, motor temperature, and battery temperature. Furthermore, a current detection device monitors the motor current, and the control system's CPU program performs a first-order derivative on this current to generate an instantaneous current increment. Additionally, the control system's parameters can preset an instantaneous current threshold and a maximum current threshold. Furthermore, the control program includes a control algorithm that analyzes the real-time instantaneous current increment and the preset current increment threshold. Finally, the control software uses this analysis to determine if the lift is overshooting, starting, or under heavy load.

[0010] The control program within the electric control component of the electric lift has an intelligent algorithm that adjusts the lift's operation or triggers an alarm to stop it based on the lift's operating status. Furthermore, in the event of an overshoot, the control program should be able to stop the lift's operation promptly before the rope breaks or other dangerous conditions occur.

[0011] Compared with the prior art, the beneficial effects of this utility model are: This type of electric hoist with overshoot protection function uses mechanical structure and internal software to determine the relationship between the rope and the electric hoist, analyze the operating status of the electric hoist, and immediately stop and alarm when overshoot occurs, so as to avoid rope breakage or damage to the electric hoist due to overshoot, thereby avoiding accidents of people or objects falling. Attached Figure Description

[0012] AppendixFigure 1 This is a schematic diagram of an electric lift with over-impact protection function according to the present invention. Appendix Figure 2 This diagram shows the structure of the rope pulley assembly of an electric lifter with overshoot protection function according to the present invention. Appendix Figure 3 This is a schematic diagram showing the internal structure of an electric lift with over-impact protection function according to the present invention. Appendix Figure 4 This invention relates to the motor current curves of an electric lifter with overshoot protection function under various operating conditions. Appendix Figure 5 This invention relates to a control flowchart for an electric lift with over-impact protection function. Appendix Figure 6 This diagram illustrates a practical application example of an electric lift device with a top-impact protection function that incorporates a utility model.

[0013] In the diagram: 100, rope pulley assembly; 101, rope pulley; 102, rope inlet guide pulley; 103, rope outlet guide pulley; 104, rope separator; 105, wall panel; 106, load-bearing connection mechanism; 107, outer shell; 108, rope; 111, figure-eight knot; 109, suspension point; 200, drive assembly; 201, reducer; 202, electromagnetic brake; 203, motor; 204, encoder; 300, electrical control system; 301, control section; 302, drive section; 303, current detection section; 304, speed control handle. Detailed Implementation

[0014] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0015] One possible embodiment of this utility model is an electric lifter with over-collision protection function, combined with an attached... Figure 1 The device consists of a housing 107, a rope pulley assembly 100 on the left side of the housing, a load-bearing connection mechanism 106 on the lower left side, and a speed control handle 304 mounted on the housing. The upper end of the rope 108 is suspended at a high suspension point 109 by a figure-eight knot 111. The rope 108 passes around the rope pulley assembly 100 and comes out from the rope pulley assembly 100. The load is connected to the load connection mechanism 106 of the electric lift. Under the action of gravity, the rope 108, the load, and the load connection mechanism 106 are basically on a vertical line of gravity.

[0016] Combined with appendix Figure 2 The electric lifter with overshoot protection function has a rope pulley assembly 100 on its left side. The rope pulley assembly 100 is mounted on a wall panel 105, which is part of the outer casing 107. The rope pulley assembly 100 includes a rope pulley 101, a rope inlet guide pulley 102, a rope outlet guide pulley 103, and a rope separator 104. The rope pulley 101 is mounted on the wall panel 105, supported by bearings, and connected to a reducer 201. The rope inlet guide pulley 102 and the rope outlet guide pulley 103 are mounted on the wall panel 105 and are rotatable with bearings. The rope inlet guide pulley 102... 2. The contact part between the rope guide wheel 103 and the rope 108 is arc-shaped to increase the constraint on the rope. The rope 108 enters the edge of the rope wheel 101 from between the rope guide wheel 102 and the rope wheel 101. The rotation of the rope wheel 101 drives the rope 108 to pass around the rope wheel 101 and leave the rope wheel between the rope wheel 101 and the rope guide wheel 103 through the friction of the edge. The rope separator 104 is located between the rope guide wheel 102 and the rope guide wheel 103 to avoid interference between the rope entry and exit. The rope guide wheel 102 and the rope exit guide wheel 103 are made of metal.

[0017] Combined with appendix Figure 3The electric lift with overshoot protection function has a drive assembly 200 and an electronic control system 300 inside its casing. The drive assembly 200 includes a reducer 201, an electromagnetic brake 202, a motor 203, and an encoder 204. Power is generated by the motor 203. The output end of the motor 203 is connected to the input end of the reducer 201. The output end of the reducer 201 is connected to one end of the pulley 101. The rotation of the motor 203 drives the rotation of the reducer 201. The high speed of the motor 203 is reduced by the reducer 201, and the output torque is amplified. The reducer 201 drives the pulley 101 to rotate, thereby enabling the electric lift to move up and down along the rope 108. The encoder 204 is installed at the end of the motor 203 and is coaxial with the motor. It is used to detect the speed and direction of the motor 203 and transmit the signal to the electronic control system 300. One end of the electronic control system 300 is electrically connected to the input end of the motor 203, thereby monitoring the direction and speed of the motor 203's rotation. The electromagnetic brake 202 is located between the motor 203 and the reducer 201. When the electric lift needs to stop, the motor 203 stops running, and the electromagnetic brake 202 de-energizes to brake and prevent the lift from falling due to gravity. The electrical control system 300 includes a control section 301, a drive section 302, and a current detection section 303. The control section 301 sends information to the drive section 302, which drives the motor 203 to run. The current detection section 303 detects the current value of the motor 203 and transmits this information to the control board 301. The drive section 302 uses a speed mode to control the motor 203 (the control target is the speed of the motor, and the current of the drive motor 203 is adjusted by accurately comparing the difference between the target speed and the actual speed). The control section 301 notifies the drive section 301 to drive the motor 203 to follow the target speed given by the speed control handle 304. When the load increases, the drive section 301 will increase the current of the motor 203 to increase the torque.

[0018] Combined with appendix Figure 4The electric lift with overshoot protection function has four typical motor drive current states in actual operation: start-up acceleration state, normal operation state, overshoot state, and descent state. In the start-up acceleration state, the motor drive current increases from 0. Due to the need for acceleration under load, the first derivative of the motor drive current is relatively large at startup. When the electric lift reaches the set speed, the motor drive current becomes constant, and the first derivative of the motor drive current becomes 0. In the normal operation state, the motor drive current is a constant value. This constant value is related to the speed; the higher the electric lift speed and the greater the load, the greater the motor drive current. When speed changes are required, the motor drive current changes from one constant value to another. Because the acceleration is limited in the control program during speed changes, the motor... The first derivative of the current can be positive or negative, and its value is smaller than that in the starting state. In the top-reaching state: before the electric lift reaches the top, it is in normal operation. When the figure-eight knot at the top of the rope enters the rope pulley assembly 100, a jamming phenomenon occurs. At this time, the motor drive current increases rapidly from a constant value, and the first derivative of the motor drive current is positive and very large, greater than the first derivative of the motor drive current in the starting state. In the descending state: the electric lift is in the descending state, and the motor drive current is negative. At this time, motor 203 acts as a generator, and the electric lift converts the gravitational potential energy of the load into electrical energy stored in the battery until motor 203 stops, at which point the current is 0.

[0019] Combined with appendix Figure 4 The electric lift with over-impact protection function has an internal electrical control system 300, which contains a CPU and software to control the operation of the electric lift. The principle of the software implementing the over-impact protection function is as follows: Quantity definition: A: Real-time motor drive current; Amax: Maximum threshold value for motor drive current setting; dA: First derivative of real-time motor drive current; dAmax: The maximum threshold value for the first derivative of the motor drive current setting; V: Real-time motor speed; Vmin: Minimum threshold for motor speed setting; During the operation of the electric lift, the electrical control system 300 continuously monitors the real-time motor drive current value A, the first derivative of the real-time motor drive current dA, and the real-time motor speed V, with a sampling time of less than 50ms. After the electric lift is powered on, the software is in operation. When it detects that the first derivative of the real-time motor drive current dD is greater than the maximum set threshold dAmax of the motor drive current, it further checks whether the real-time motor drive current value A is greater than the maximum set threshold Amax. If so, it further checks whether the real-time motor speed is less than the minimum set threshold Vmin of the motor speed. If so, the electrical control system software will trigger the overshoot protection function, immediately stop the machine, and issue an alarm. Alternatively, when it detects that the first derivative of the real-time motor drive current dA is less than the maximum set threshold dAmax, the electrical control system software judges this as normal acceleration / deceleration and does not perform any fault handling. Another scenario is when it detects that the first derivative of the real-time motor drive current dA is greater than the maximum set threshold dAmax, while the real-time motor drive current value A is less than the maximum set threshold Amax, which is a small load rapid acceleration process and also considered normal operation. In another scenario, if the real-time motor drive current first derivative dA is greater than the maximum set threshold dAmax, and the real-time motor drive current value A is greater than the maximum set threshold Amax, and the real-time motor speed is greater than the minimum set threshold Vmin, this also constitutes an overshoot phenomenon, except that it is not jammed. The rope and pulley are in a slipping state, and the machine should be stopped immediately and an alarm should be triggered. Otherwise, prolonged slippage will damage the rope.

[0020] Appendix Figure 6 An embodiment of an electric hoist with overshoot protection is shown. In this embodiment, a worker wearing a safety harness operates the electric hoist to move upwards. A reliable suspension point is located at the height, and a rope is suspended from it. The upper end of the rope is tied in a figure-eight knot and attached to the suspension point with a metal loop. Furthermore, if the operator accidentally causes the electric hoist to overshoot (i.e., the figure-eight knot of the rope gets caught in the rope pulley assembly of the electric hoist), the electric hoist immediately stops and sounds an alarm, regardless of the operator's actions. Further, after the operator detects the electric hoist's stoppage and the alarm signal, they observe the safety status of the rope. If the rope is still in a reliable state, the power to the electric hoist is turned off, and the electric hoist is lowered manually. If the rope is in an unreliable state or the situation cannot be determined, an alternative safety method, such as a descender, should be used for descent.

Claims

1. An electric lift with over-impact protection function, characterized in that, The system includes a pulley assembly (100), a load-bearing connection mechanism (106), a drive assembly (200), an electrical control system (300), a housing (107), a rope (108), and a battery assembly. The pulley assembly (100) is provided with a pulley cover. Inside the pulley cover are a pulley (101), a rope inlet guide pulley (102), a rope outlet guide pulley (103), and a rope separator (104). The upper end of the rope (108) is suspended from a high point by a figure-eight knot (111). (109) The rope (108) enters the rope wheel (101) between the rope inlet guide wheel (102) and the rope wheel (101). The rope (108) passes around the rope wheel (101) and exits the rope wheel (101) between the rope wheel (101) and the rope outlet guide wheel (103). A load-bearing connection mechanism (106) is provided below the rope wheel assembly (100). The rope (108), the rope wheel assembly (100), and the load-bearing connection mechanism (106) are on the same vertical line of gravity.

2. An electric lift with over-impact protection function according to claim 1, characterized in that, The electronic control system (300) includes a control part (301), a drive part (302) and a current detection part (303), and the control part (301) is connected to a speed control handle (304).

3. An electric lift with over-impact protection function according to claim 1, characterized in that, The drive assembly (200) includes a reducer (201), an electromagnetic brake (202), a motor (203), and an encoder (204). The output end of the motor (203) is connected to the input end of the reducer (201), and the output end of the reducer (201) is connected to one end of the pulley (101). An encoder (204) is installed at the end of the motor (203), and an electromagnetic brake (202) is located between the motor (203) and the reducer (201).

4. An electric lift with over-impact protection function according to claim 1, characterized in that, A wall panel (105) is installed on one side of the outer casing (107), and a load-bearing connection mechanism (106) is provided at the lower end of the wall panel (105).

5. An electric lift with over-impact protection function according to claim 1, characterized in that, A rope separator (104) is provided between the rope inlet guide wheel (102) and the rope outlet guide wheel (103), and the rope inlet guide wheel (102) and the rope outlet guide wheel (103) are made of metal.

6. An electric lift with over-impact protection function according to claim 3, characterized in that, One end of the electronic control system (300) is electrically connected to the input end of the motor (203).

7. An electric lift with over-impact protection function according to claim 1, characterized in that, The rope wheel (101) is divided into an inner rope wheel and an outer rope wheel.

8. An electric lift with over-impact protection function according to claim 1, characterized in that, The edge of the rope wheel (101) is provided with a ridge.

Images