Electric shovel cable winding protection device

Abstract

This utility model discloses a cable rewinding protection device for an electric loader, including multiple magnetic blocks mounted on the side plate of the drum and a sensing probe mounted on the rear frame. It also includes a pressure controller, a stop detection controller, and a stop relay. This utility model detects a stop by sensing the magnetic blocks that rotate with the drum. When a stop occurs, an emergency stop braking control circuit controls the loader to brake, thereby preventing the loader from continuing to retreat and causing cable damage due to the drum stopping. This utility model also has the advantages of simple structure, low cost, and high reliability.

Description

Technical Field

[0001] This utility model relates to a cable rewind protection device for a loader. Background Technology

[0002] Electric loaders are commonly used equipment in mining operations for loading and transporting materials. They use an electric motor as a power source and are powered by a tow cable. The cable is wound on a drum at the rear of the loader. When the loader moves forward, the cable drives the drum to rotate (or the drum rotates forward under the action of the motor) to release the cable. When the loader moves backward, the motor drives the drum to reverse to retrieve the cable, so that the cable length matches the position of the loader.

[0003] Chinese utility model patent CN201771548U discloses a synchronous cable winding mechanism for a shovel loader, including a hydraulic cylinder, a limit switch, an hydraulic pump, and a drive motor connected to the hydraulic pump. Two ports of the hydraulic pump are correspondingly connected to two ports of the drive motor. The output shaft of the drive motor is connected to the transfer case of the shovel loader, driving the shovel loader to move. When the hydraulic pump rotates forward, it drives the drive motor to rotate synchronously forward via hydraulic oil, propelling the vehicle forward; conversely, when the hydraulic pump rotates backward, it drives the drive motor to rotate in reverse, propelling the vehicle backward. This design also uses the hydraulic cylinder and limit switch to detect the direction of travel, thereby controlling the drum to rotate in the correct direction.

[0004] However, existing loaders (especially those disclosed in the aforementioned patent) have the following problems when reeling in and unloading cables: 1. When the cable is pressed down or tangled with foreign objects, the drum will be unable to wind up the cable properly and will stop rotating. If the loader continues to move backward at this time, the cable will be crushed and damaged. 2. Existing solutions that rely on hydraulic cylinders and limit switches to detect the loader's direction of movement rely on hydraulic cylinders. Once the hydraulic cylinder encounters resistance and stops, no signal can be obtained, resulting in poor reliability. Furthermore, such hydraulic cylinders require separate design and production, leading to high hardware costs. Utility Model Content

[0005] This utility model proposes a cable rewinding protection device for electric shovels, the purpose of which is to: 1. solve the problem that the shovel cannot stop reversing in time when the drum stops rotating, resulting in cable damage; 2. solve the problems of poor reliability and high hardware cost when using a hydraulic cylinder to obtain the driving direction.

[0006] The technical solution of this utility model is as follows:

[0007] An electric shovel loader cable rewind protection device is disclosed. The electric shovel loader includes a drum with a cable wound on it, mounted on a rear frame, and the drum has a drum side plate. The electric shovel loader also includes an oil pump and a drive motor. The first oil port of the oil pump is connected to the third oil port of the drive motor through a forward pipeline, and the second oil port of the oil pump is connected to the fourth oil port of the drive motor through a reverse pipeline. The drive motor is connected to the input shaft of the electric shovel loader's transfer case and is used to drive the electric shovel loader to move. The electric shovel loader also includes an emergency stop brake control circuit, which includes a brake solenoid valve Y1. The brake solenoid valve Y1 is used to control the opening and closing of the brake oil circuit of the electric shovel loader. The electric shovel loader cable rewind protection device includes multiple magnetic blocks mounted on the drum side plate and a sensing probe mounted on the rear frame. The magnetic blocks are evenly distributed around the axis of the drum. The sensing probe is used to sense the magnetic field signal of the magnetic blocks.

[0008] The electric loader cable rewind protection device also includes a pressure controller installed on the retraction pipeline, used to detect whether the pressure of the retraction pipeline exceeds a preset threshold.

[0009] The electric shovel loader cable rewind protection device also includes a stop detection controller and a stop relay KA2; the positive power supply of the electric shovel loader is connected to the positive power input terminal of the stop detection controller through the normally open contact and common terminal of the pressure controller, the negative power supply of the electric shovel loader is connected to the negative power input terminal of the stop detection controller, the signal output terminal of the sensing probe is connected to the signal input terminal of the stop detection controller, the signal output terminal of the stop detection controller is connected to one end of the coil of the stop relay KA2, and the other end of the coil of the stop relay KA2 is connected to the negative power supply of the electric shovel loader; the normally closed contact and common terminal of the coil of the stop relay KA2 are connected in the emergency stop braking control circuit.

[0010] As a further improvement to the electric loader cable rewind protection device: the magnetic block is installed on the side plate of the drum by magnetic attraction.

[0011] As a further improvement to the electric shovel loader cable rewind protection device: the magnetic block is cylindrical, and its diameter is 1 to 3 times the diameter of the end of the sensing probe.

[0012] As a further improvement to the electric loader cable rewind protection device: the sensing probe is mounted on the rear frame via a bracket.

[0013] As a further improvement to the electric loader cable reel protection device: the bracket is L-shaped, including a base plate and a vertical plate, the base plate being fixed to the rear frame by screws; the outer cylindrical surface of the sensing probe is provided with external threads; the sensing probe passes vertically through the vertical plate of the bracket and is fixed to the vertical plate by two locking nuts located on both sides of the vertical plate respectively.

[0014] As a further improvement to the electric loader cable winding protection device: the upright plate is provided with a vertical waist-shaped groove parallel to the drum side plate, and the sensing probe passes through the vertical waist-shaped groove.

[0015] As a further improvement to the cable rewinding protection device for the electric loader: the base plate is provided with a transverse waist-shaped groove parallel to the drum side plate, and the screw passes through the transverse waist-shaped groove.

[0016] As a further improvement to the cable rewind protection device for the electric loader, an emergency stop button ES is also connected in series in the emergency stop braking control circuit.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. This utility model detects a stop by sensing a magnetic block that rotates with the drum. When a stop occurs, the emergency stop braking control circuit controls the loader to brake, thereby preventing the loader from continuing to retreat due to the drum stopping and causing damage to the cable.

[0019] 2. This utility model uses a pressure controller installed on the reversing pipeline to detect whether the current state is reversed, and only connects the power supply to the stop detection controller when the reverse state is reversed. It has a simple structure, low cost and high reliability.

[0020] 3. By increasing the diameter of the magnetic block, this utility model reduces the requirements for the installation accuracy of the magnetic block, and can still reliably trigger the sensing probe even if the position of the magnetic block is slightly off.

[0021] 4. This utility model allows for adjustment of the position of the sensing probe and its distance from the magnetic block via the vertical and horizontal waist-shaped grooves and locking nuts on the bracket, ensuring a stable and reliable sensing signal. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of an electric loader equipped with this protective device;

[0023] Figure 2 This is a schematic diagram of the layout of the magnetic blocks on the side plate of the drum;

[0024] Figure 3 This is a partial structural diagram of the sensing probe, support, and magnetic block.

[0025] Figure 4 This is a schematic diagram showing the connection relationship between the oil pump, pressure controller, and drive motor.

[0026] Figure 5 This is the electrical control schematic diagram of this utility model.

[0027] The reference numerals in the figures include:

[0028] 1. Drum side plate; 2. Rear frame; 3. Magnetic block; 4. Induction probe; 5. Locking nut; 6. Vertical waist-shaped groove; 7. Bracket; 8. Screw; 9. Horizontal waist-shaped groove; 10. Oil pump; 11. Drive motor; 12. Forward pipeline; 13. Reverse pipeline; 14. Pressure controller; 15. Stop detection controller. Detailed Implementation

[0029] The technical solution of this utility model will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments.

[0030] An electric shovel loader cable reel protection device is installed on the electric shovel loader to detect whether the drum has stopped rotating and to trigger the brake when it stops, thereby protecting the cable.

[0031] like Figure 1 The electric shovel loader includes a drum with a cable wound around it, mounted on the rear frame 2. The drum has an iron drum side plate 1. The cable is used to supply power to the electric shovel loader. The electrical energy is converted into hydraulic energy through a hydraulic station to drive the hydraulic motor, cylinders and other components of the shovel loader. The electrical energy can also power the motor, control system and other components.

[0032] like Figure 4 The electric shovel also includes an oil pump 10 and a drive motor 11. The first oil port of the oil pump 10 is connected to the third oil port of the drive motor 11 via a forward pipeline 12, and the second oil port of the oil pump 10 is connected to the fourth oil port of the drive motor 11 via a reverse pipeline 13. The drive motor 11 is connected to the input shaft of the electric shovel's transfer case and is used to drive the electric shovel to move. When the oil pump 10 rotates forward, it supplies pressurized oil to the drive motor 11 through the forward pipeline 12 and returns oil through the reverse pipeline 13, causing the drive motor 11 to rotate forward, thus driving the electric shovel forward. At this time, the pressure in the forward pipeline 12 is higher, and the pressure in the reverse pipeline 13 is lower. When the oil pump 10 rotates in reverse, it supplies pressurized oil to the drive motor 11 through the reverse pipeline 13 and returns oil through the forward pipeline 12, causing the drive motor 11 to rotate in reverse, thus driving the electric shovel backward. At this time, the pressure in the forward pipeline 12 is lower, and the pressure in the reverse pipeline 13 is higher.

[0033] The electric loader cable reel protection device includes multiple magnetic blocks 3 installed on the drum side plate 1 and an induction probe 4 installed on the rear frame 2. The induction probe 4 is cylindrical with external threads on the outer cylindrical surface, used to sense the magnetic field signal of the magnetic blocks 3.

[0034] In this embodiment, as Figure 2There are three magnetic blocks 3, which are magnetically attached to the side plate 1 of the drum and evenly distributed around the axis of the drum at 120° intervals. The diameter of the magnetic block 3 is 1 to 3 times the diameter of the end of the sensing probe 4, so that even if the position of the magnetic block 3 is slightly off, the sensing probe 4 can still sense normally.

[0035] like Figure 3 The sensing probe 4 is mounted on the rear frame 2 via a bracket 7. The bracket 7 is L-shaped and includes a base plate and a vertical plate. The vertical plate has a vertical slot 6 parallel to the drum side plate 1, and the base plate has a horizontal slot 9 parallel to the drum side plate 1. The sensing probe 4 passes vertically through the vertical slot 6 and is fixed to the vertical plate by two locking nuts 5 located on either side of the vertical plate. The base plate is fixed to the top of the rear frame 2 side plate by screws 8 passing through the horizontal slot 9. After loosening the locking nuts 5, the height of the sensing probe 4 can be adjusted along the vertical slot 6, and the distance between the sensing probe 4 and the magnetic block 3 can also be adjusted. After loosening the screws 8, the horizontal position of the sensing probe 4 relative to the magnetic block 3 can be adjusted. Through this structure, the spatial position of the sensing probe 4 can be arbitrarily adjusted, ensuring that the sensing probe 4 is located on the distribution circle of the magnetic block 3 and at a suitable distance from the magnetic block 3, enabling accurate sensing.

[0036] The electric loader cable rewind protection device also includes a pressure controller 14 installed on the reversing pipe 13 via a tee, used to detect whether the pressure in the reversing pipe 13 exceeds a preset threshold. When the operator controls the loader to reverse, the pressure in the reversing pipe 13 will inevitably be higher than the preset threshold, and the pressure controller 14 will send a control signal.

[0037] Specifically, the pressure controller 14 in this embodiment is model JX-KG-B1, which can be set with two pressure limit values, each limit value corresponding to a set of normally closed contacts, normally open contacts and a common terminal. The pressure controller 14 can also output digital pressure measurement values.

[0038] like Figure 5 The electric shovel also includes an emergency stop control circuit, in which an emergency stop button ES and a brake solenoid valve Y1 are connected in series. When the emergency stop button ES is pressed, the brake solenoid valve Y1 is de-energized, thereby opening the emergency braking oil circuit of the electric shovel. At this time, the emergency braking module of the shovel is activated by the hydraulic oil to achieve emergency braking.

[0039] Furthermore, the electric loader cable reel protection device also includes a stop detection controller 15 and a stop relay KA2.

[0040] In this embodiment, the stop detection controller 15 is a Haodesheng HDS-DJTZ model, which has one input and one output, and a time setting function. Whenever there is a signal at the input terminal, the internal timer is reset. If the timer ends, it indicates that there is no signal at the input terminal within the set time period, and a control signal will be output at this time.

[0041] like Figure 5 The signal output terminal of the sensing probe 4 is connected to the signal input terminal of the stop detection controller 15. The positive terminal (24V) of the electric loader's power supply is connected to the positive terminal of the power input terminal of the stop detection controller 15 through the normally open contact and common terminal of the pressure controller 14, and the negative terminal of the electric loader's power supply is connected to the negative terminal of the power input terminal of the stop detection controller 15. The signal output terminal of the stop detection controller 15 is connected to one end of the coil of the stop relay KA2, and the other end of the coil of the stop relay KA2 is connected to the negative terminal of the electric loader's power supply. The normally closed contact and common terminal of the stop relay KA2 coil are connected in the emergency stop braking control circuit.

[0042] The emergency stop brake control circuit, emergency stop button ES, emergency brake hydraulic circuit, and emergency brake module are all built-in functional modules of the electric loader. When implementing this solution, it is only necessary to add a stop relay KA2 to the existing emergency stop brake control circuit, and control the stop relay KA2 through the signal of the stop detection controller 15.

[0043] The working process of this device is as follows:

[0044] When the electric loader moves forward, the pressure in the reverse pipeline 13 is low, the pressure controller 14 is not triggered, and its normally open contact and common terminal are not connected. Therefore, the stop detection controller 15 is not energized, and the normally closed contact and common terminal of the stop relay KA2 coil remain closed. At this time, the brake solenoid valve Y1 will only be de-energized and emergency braking will be performed when the user presses the emergency stop button ES.

[0045] When the electric loader reverses, the pressure in the reverse pipeline 13 is high, triggering the pressure controller 14. Its normally open contact and common terminal close, energizing the stop detection controller 15 and resetting the timer. Simultaneously, it detects the signal from the sensing probe 4. In this embodiment, the normal rotation speed of the drum when winding up the cable is one revolution every 2 seconds. Theoretically, the sensing probe 4 will send a signal every 0.67 seconds, so the timer can be set to 1 second. If the timer does not receive a signal from the sensing probe 4 within 1 second (no magnetic block 3 is detected), it indicates that the drum has stopped. At this time, a high level (24V) will be output through the signal output terminal, energizing the coil of the stop relay KA2. The normally closed contact and common terminal of the stop relay KA2 will open, de-energizing the brake solenoid valve Y1 and performing emergency braking to prevent the loader from damaging the cable.

[0046] It should be noted that, as will be apparent to those skilled in the art, this utility model is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this utility model. The scope of this utility model is defined by the claims rather than the foregoing description.

Claims

1. A cable reel protection device for an electric shovel loader, the electric shovel loader including a drum on a rear frame (2) with a cable wound around it, the drum having a drum side plate (1); the electric shovel loader also includes an oil pump (10) and a drive motor (11), the first oil port of the oil pump (10) being connected to the third oil port of the drive motor (11) through a forward pipeline (12), the second oil port of the oil pump (10) being connected to the fourth oil port of the drive motor (11) through a reverse pipeline (13), the drive motor (11) being connected to the input shaft of the transfer case of the electric shovel loader for driving the electric shovel loader to move; the electric shovel loader also includes an emergency stop braking control circuit, the emergency stop braking control circuit including a brake solenoid valve Y1, the brake solenoid valve Y1 being used to control the opening and closing of the brake oil circuit of the electric shovel loader; characterized in that: The electric loader cable winding protection device includes multiple magnetic blocks (3) installed on the side plate (1) of the drum and an induction probe (4) installed on the rear frame (2); the magnetic blocks (3) are evenly distributed around the axis of the drum; the induction probe (4) is used to sense the magnetic field signal of the magnetic blocks (3). The electric loader cable rewind protection device also includes a pressure controller (14) installed on the retraction pipe (13) for detecting whether the pressure of the retraction pipe (13) exceeds a preset threshold. The electric shovel loader cable rewind protection device also includes a stop detection controller (15) and a stop relay KA2; the positive power supply of the electric shovel loader is connected to the positive power input terminal of the stop detection controller (15) through the normally open contact and common terminal of the pressure controller (14), the negative power supply of the electric shovel loader is connected to the negative power input terminal of the stop detection controller (15), the signal output terminal of the induction probe (4) is connected to the signal input terminal of the stop detection controller (15), the signal output terminal of the stop detection controller (15) is connected to one end of the coil of the stop relay KA2, and the other end of the coil of the stop relay KA2 is connected to the negative power supply of the electric shovel loader; the normally closed contact and common terminal of the coil of the stop relay KA2 are connected in the emergency stop braking control circuit.

2. The electric shovel cable reeling protection device according to claim 1, characterized by: The magnetic block (3) is installed on the side plate (1) of the drum by magnetic attraction.

3. The electric shovel cable reeling protection device according to claim 1, characterized by: The magnetic block (3) is cylindrical, and its diameter is 1 to 3 times the diameter of the end of the sensing probe (4).

4. The electric shovel cable reeling protection device according to claim 1, characterized by: The sensing probe (4) is mounted on the rear frame (2) via a bracket (7).

5. The electric shovel cable reeling protection device according to claim 4, characterized by: The bracket (7) is L-shaped and includes a base plate and a vertical plate. The base plate is fixed to the rear frame (2) by screws (8). The outer cylindrical surface of the sensing probe (4) is provided with external threads. The sensing probe (4) passes vertically through the vertical plate of the bracket (7) and is fixed to the vertical plate by two locking nuts (5) located on both sides of the vertical plate.

6. The electric shovel cable reeling protection device according to claim 5, characterized by: The upright plate is provided with a vertical waist-shaped groove (6) parallel to the drum side plate (1), and the sensing probe (4) passes through the vertical waist-shaped groove (6).

7. The electric shovel cable reeling protection device according to claim 5, characterized by: The base plate is provided with a transverse waist-shaped groove (9) parallel to the drum side plate (1), and the screw (8) passes through the transverse waist-shaped groove (9).

8. The cable reel protection apparatus for a motorized scraper as set forth in any of claims 1-7, wherein: An emergency stop button ES is also connected in series in the emergency stop braking control circuit.

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