Low-clearance hoist

Abstract

The utility model belongs to the field of lifting hooks, and relates to a low-clearance hoist which comprises a limit switch, a rocker, a lifting hook buffer spring, a limit spring and a low-clearance bracket, the limit switch is integrated into the low-clearance bracket, is matched with the rocker and is used for detecting the position of the lifting hook; the rocker is used for connecting the limit switch and the hook buffer spring; the lifting hook buffer spring is used for relieving the impact force of the lifting hook on the rocker in the lifting process, so that the limiting switch and the rocker are protected from being damaged; the limiting spring is used for providing reset force for the warping plate when the lifting hook descends to a preset position, so that the warping plate can restore to the initial position; the limiting spring is arranged below the warping plate and is connected with the low clearance bracket; and the low clearance bracket is used for supporting and fixing the limit switch, the rocker, the lifting hook buffer spring and the limit spring. The lifting device is simple in structure, compact in structure, small in occupied space and high in reliability and safety, and an effective solution is provided for lifting operation in a low-clearance place.

Description

Technical Field

[0001] This utility model relates to the field of hook technology, and more specifically, to a low headroom hoist. Background Technology

[0002] The current problems of unsafe and unreliable lifting operation and non-compact structure of low headroom hoists are mainly reflected in the following aspects:

[0003] First, from a safety and reliability perspective, some low-headroom hoists may have design flaws during lifting. For example, if the operating switch is too high above the ground, operators are easily injured by collisions or impacts from the load due to improper positioning. Furthermore, an imperfect braking system is also a significant hazard; for instance, if the brake ring is not fully contained within the brake wheel, it may lead to brake failure, potentially causing the load to fall and injure people.

[0004] Secondly, regarding structural compactness, although low-headroom hoists were originally designed to solve the lifting challenges posed by height restrictions, some products sacrificed structural compactness in achieving this function. This can result in a large overall size of the hoist, occupying too much space and hindering flexible operation in confined or height-restricted factory workshops. Furthermore, a non-compact structure can also affect the hoist's stability and durability, increasing the failure rate and maintenance costs. Utility Model Content

[0005] To address the aforementioned deficiencies in the existing technology, this utility model provides a low headroom hoist, comprising:

[0006] The system includes a limit switch, a rocker arm, a hook buffer spring, a limit spring, and a low headroom bracket. The limit switch is integrated into the low headroom bracket and works in conjunction with the rocker arm. The limit switch is used to detect the hook position. The rocker arm connects the limit switch and the hook buffer spring. The hook buffer spring reduces the impact force on the rocker arm during the hook's ascent, thus protecting the limit switch and rocker arm from damage. The limit spring provides a restoring force to the rocker arm when the hook descends to a preset position, allowing it to return to its initial position. The limit spring is located below the rocker arm and connected to the low headroom bracket. The low headroom bracket supports and secures the limit switch, the rocker arm, the hook buffer spring, and the limit spring.

[0007] Preferably, it also includes a control circuit for controlling the lifting of the low headroom hoist.

[0008] Preferably, the rocker is made of metal.

[0009] Preferably, the control circuit includes a power module, a lifting button, a limit switch, and a controller that are electrically connected.

[0010] Preferably, the power module includes an overload protection circuit and a short-circuit protection circuit.

[0011] Preferably, the controller includes a programmable logic controller.

[0012] Preferably, the controller includes a fault detection module.

[0013] Preferably, the controller includes an alarm module.

[0014] Preferably, the overload protection circuit includes: a fuse, a thermal relay, an electronic overload relay, a current transformer, a circuit breaker, and a sampling resistor connected in series.

[0015] Preferably, the short-circuit protection circuit includes: an automatic air switch, an overcurrent relay, and a transistor. The automatic air switch and the overcurrent relay are connected in series, and then connected in parallel with the transistor.

[0016] The low-headroom hoist of this utility model has the following beneficial effects: By creating a rocker installation space within the low-headroom bracket, and integrating the limit switch activation structure into the bracket, the standard structure in the industry is raised, saving 100mm of usable space; during use, the hook moves upward, and through the hook buffer spring, pushes the rocker to activate the limit switches on both sides (the limit switches on both sides are connected in series with the lifting button), disconnecting the circuit and stopping the lifting action. Even if one limit switch fails to function, the control system can still control the lifting action normally, increasing the overall safety of the operating system; while improving space utilization, it ensures the safety and reliability of the lifting action; it not only has the characteristics of compact structure and small space occupation, but also has high reliability and safety, providing an effective solution for lifting operations in low-headroom locations. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort. The utility model will be further described below in conjunction with the drawings and embodiments. In the drawings:

[0018] Figure 1 This is a rear view of the low headroom hoist of this utility model;

[0019] Figure 2 This is an isometric view of the low headroom hoist of this utility model;

[0020] Figure 3 This is a front view of the low headroom hoist of this utility model;

[0021] Figure 4 This is a top view of the low headroom hoist of this utility model;

[0022] Figure 5 This is a bottom view of the low headroom hoist of this utility model;

[0023] Figure 6 This is a right view of the low headroom hoist of this utility model;

[0024] Figure 7 This is a front view of the low headroom hoist of this utility model;

[0025] Figure 8 This is a left view of the low headroom hoist of this utility model.

[0026] In the diagram, 1-limit switch, 2-rocker, 3-hook buffer spring, 4-limit spring, 5-low headroom bracket. Detailed Implementation

[0027] 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.

[0028] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0029] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0030] Figure 1 This is a rear view of the low headroom hoist of this utility model; Figure 2 This is an isometric view of the low headroom hoist of this utility model; Figure 3 This is a front view of the low headroom hoist of this utility model; Figure 4 This is a top view of the low headroom hoist of this utility model; Figure 5 This is a bottom view of the low headroom hoist of this utility model; Figure 6 This is a right view of the low headroom hoist of this utility model; Figure 7 This is a front view of the low headroom hoist of this utility model; Figure 8 This is a left view of the low headroom hoist of this utility model. Please refer to [link / reference]. Figures 1-8 The low headroom hoist provided in the first embodiment of this utility model includes at least a limit switch 1, a rocker arm 2, a hook buffer spring 3, a limit spring 4, and a low headroom bracket 5. The limit switch 1 is integrated into the low headroom bracket 5 and cooperates with the rocker arm 2. The limit switch 1 is used to detect the position of the hook. The rocker arm 2 is used to connect the limit switch 1 and the hook buffer spring 3. The hook buffer spring 3 is used to reduce the impact force of the hook on the rocker arm 2 during the lifting process, thereby protecting the limit switch 1 and the rocker arm 2 from damage. The limit spring 4 is used to provide a restoring force to the rocker arm 2 when the hook descends to the preset position, so that it can return to the initial position. The limit spring 4 is located below the rocker arm 2 and is connected to the low headroom bracket 5. The low headroom bracket 5 is used to support and fix the limit switch 1, the rocker arm 2, the hook buffer spring 3, and the limit spring 4.

[0031] In practical implementation, the low headroom hoist of this utility model also includes a control circuit, which is used to control the lifting of the low headroom hoist.

[0032] Limit switch 1 is an important component in low headroom hoists used to detect the position of the hook. When the hook rises to the preset position, limit switch 1 is triggered, and the lifting action is stopped by the control circuit, thereby avoiding accidents caused by excessive hook rise.

[0033] In this embodiment, the triggering mechanism of the limit switch 1 can adopt a mechanical contact, which has the characteristics of simple structure and high reliability.

[0034] The rocker arm 2 is a key component connecting the limit switch 1 and the hook buffer spring 3. When the hook rises, it first contacts the hook buffer spring 3, and the spring force pushes the rocker arm 2 upward. During its movement, the rocker arm 2 triggers the limit switch 1, thereby detecting the position of the hook. In practice, the rocker arm 2 can be made of metal materials such as carbon steel and stainless steel.

[0035] Metal materials such as carbon steel and stainless steel can provide sufficient mechanical strength while maintaining low weight, meeting the durability requirements of rocker 2 in frequent, heavy-duty operations.

[0036] The hook buffer spring 3 is used to reduce the impact force of the hook on the rocker 2 during the lifting process, thereby protecting the limit switch 1 and the rocker 2 from damage. At the same time, the hook buffer spring 3 can also provide sufficient elastic force to the rocker 2 so that it can smoothly trigger the limit switch 1.

[0037] In this embodiment, the hook buffer spring 3 is installed between the hook and the rocker arm 2. By adjusting the initial position of the spring, precise control of the final stopping position of the hook can be achieved. Furthermore, the selection and installation position of the spring can be determined according to actual needs to ensure that it meets the equipment's usage requirements.

[0038] The limit spring 4 provides a restoring force to the rocker arm 2 when the hook descends to the preset position, allowing it to return to its initial position. Simultaneously, the limit spring 4 also provides auxiliary support during the hook's ascent, improving the stability and safety of the equipment.

[0039] In this embodiment, the limiting spring 4 is installed below the rocker 2 and connected to the low headroom bracket 5. By adjusting the spring's stiffness and preload, precise control of the rocker 2's reset speed and stability can be achieved. Furthermore, the selection and installation position of the limiting spring 4 can be determined according to actual needs to ensure it meets the equipment's usage requirements.

[0040] The low headroom support 5 is the main structure of the low headroom hoist, used to support and fix other components. In this embodiment, the low headroom support 5 is made of high-strength material, possessing sufficient rigidity and stability to reduce the height of the equipment and the space it occupies.

[0041] In practice, the control circuit includes a power module, a lifting button, limit switches, and a controller that are electrically connected.

[0042] The power module provides electrical energy to the low headroom hoist of this invention, ensuring its normal operation. In this embodiment, the power module uses AC power and is connected to the controller via a cable. The power module also includes overload protection circuits and short-circuit protection circuits, providing overload and short-circuit protection functions to ensure the safety of the low headroom hoist during use.

[0043] In practice, the overload protection circuit includes: a fuse, a thermal relay, an electronic overload relay, a current transformer, a circuit breaker, and a sampling resistor connected in series.

[0044] A fuse is a simple yet effective overload protection device. It contains a metal wire that melts due to overheating when the current exceeds the fuse's rated value, thus quickly cutting off the circuit. Fuses are characterized by low cost, ease of replacement, and fast response.

[0045] Thermal relays utilize the thermal effect of electric current to achieve overload protection. They are typically composed of a bimetallic strip, which bends due to heat when current flows through it. When the bend reaches a certain point, it triggers a mechanical device to cut off the circuit.

[0046] Electronic overload relays monitor the current level in the circuit in real time using a current sensor. When the current exceeds a preset threshold, the relay sends a signal to cut off the power supply. Electronic overload relays offer fast response and high accuracy.

[0047] Current transformers play a crucial role in overload protection circuits by accurately detecting current magnitude. They proportionally convert high current into low current for sampling and processing by the protection device. Once an abnormal current is detected, the protection device immediately disconnects the circuit.

[0048] Circuit breakers are a key component of overload protection circuits. When the current exceeds its rated value, the tripping mechanism inside the circuit breaker will act quickly, causing the contacts to separate and thus cutting off the circuit in a very short time.

[0049] In an overcurrent protection circuit, a sampling resistor is used to detect the current. When the current exceeds a set value, the voltage drop across the sampling resistor triggers the protection circuit, cutting off the power supply.

[0050] In practice, the short-circuit protection circuit includes: an automatic air switch, an overcurrent relay, and a transistor. The automatic air switch and the overcurrent relay are connected in series, and then connected in parallel with the transistor.

[0051] An automatic air circuit breaker is an electrical appliance with overload and short-circuit protection functions. It can automatically trip and cut off the power supply when an overload or short circuit occurs in the circuit. Compared with fuses, automatic air circuit breakers have advantages such as reusability, accurate operation, and comprehensive protection functions.

[0052] An overcurrent relay is an electrical device that detects the magnitude of current and takes corresponding actions. When the current in a circuit exceeds a set value, the overcurrent relay will trip, disconnecting the connected contactor or relay, thereby protecting the circuit. Overcurrent relays are used in conjunction with automatic air switches to improve the reliability and accuracy of protection.

[0053] In short-circuit protection circuits, transistors are typically used to sample the output voltage and determine whether a short circuit has occurred based on changes in the output voltage. Transistors have advantages such as small size, low power consumption, and fast response speed.

[0054] The lifting button is used to control the lifting action of the low headroom hoist. When the lifting button is pressed, the controller receives a signal and starts driving the motor to raise the hook. In this embodiment, the lifting button is connected in series in the control circuit, and together with the limit switches on both sides, controls the lifting action.

[0055] Limit switches are used to detect the position of the hook and trigger the control circuit when the hook reaches a preset position, stopping the lifting operation. In this embodiment, limit switches are installed on both sides of the low headroom bracket 5 and connected to the rocker arm 2. When the hook rises, it first contacts the hook buffer spring 3, pushing the rocker arm 2 upward, thereby triggering the limit switches. When either limit switch is triggered, the lifting operation will be stopped via the control circuit.

[0056] To improve equipment reliability and safety, a redundant control mechanism can be designed. If one limit switch fails, the other limit switch can still function normally, ensuring the control circuit can properly control the lifting action. This redundant control mechanism significantly improves equipment reliability and safety, reducing the risk of accidents caused by a single failure.

[0057] The controller is the core component of the low-headroom hoist circuit control section. It receives signals from the lifting button and limit switches, and controls the motor's operation and stop according to a preset program and logic. The controller includes a programmable logic controller (PLC). PLCs offer advantages such as flexible programming, high reliability, and ease of maintenance.

[0058] In practical implementation, the controller may also include a fault detection module. When a fault occurs in the equipment, the controller can automatically detect the fault and issue an alarm signal to remind the user to handle it in a timely manner. At the same time, the controller can also record fault information to facilitate fault analysis and troubleshooting by the user.

[0059] The fault detection module may include a main control chip, sensors, analog-to-digital conversion circuits, storage modules, and communication modules.

[0060] As the core of the fault detection module, the main control chip is responsible for data processing, logical judgment, and instruction output. The main control chip can be a high-performance microcontroller or single-chip microcomputer, such as the STM32 series, which possesses powerful data processing capabilities and rich peripheral interfaces.

[0061] Sensors act as the eyes of the fault detection module, collecting various operating parameters of the equipment in real time, such as temperature, pressure, current, and vibration. Sensors include temperature sensors, pressure sensors, current sensors, and vibration sensors. These sensors convert analog signals into digital signals for processing by the main control chip.

[0062] Since the sensor outputs analog signals while the main control chip processes digital signals, an analog-to-digital converter (ADC) is needed to convert the analog signals into digital signals. The accuracy and speed of the ADC have a significant impact on the accuracy of fault detection.

[0063] The storage module stores the configuration information, historical data, and diagnostic results of the fault detection module. Storage devices include EEPROM and Flash memory. These memories are non-volatile, ensuring data integrity even when power is lost.

[0064] The communication module is responsible for uploading data and diagnostic results from the fault detection module to the upper-level monitoring system or cloud platform. Communication methods include serial communication, Ethernet communication, WiFi, and Bluetooth. The choice of these methods depends on the application scenario and transmission distance.

[0065] In practical implementation, the controller may also include an alarm module. The alarm module includes indicator devices such as LED indicators and LCD screens to display equipment status and fault types, as well as alarm devices such as buzzers and audible and visual alarms to emit sound or light signals to alert operators.

[0066] Sensors collect various operating parameters of the equipment in real time, such as temperature, pressure, and current, and convert these analog signals into digital signals. These digital signals are transmitted to the main control chip via an ADC circuit. After receiving the digital signals from the sensors, the main control chip performs data processing and logical judgment. It compares these data with preset thresholds; if the threshold is exceeded, a fault is identified. Information such as the fault type, severity, and fault location is stored in the storage module. Once a fault is detected, the main control chip controls the indicator and alarm module to issue fault information. LED indicators will display different colors or flashing patterns to indicate the fault type (e.g., green for normal, yellow for warning, and red for serious fault). The LCD screen will provide more detailed fault information, such as fault codes and fault descriptions. A buzzer will sound an alarm to remind operators to handle the fault promptly.

[0067] The working principle of this low headroom hoist involves two aspects: mechanical transmission and circuit control.

[0068] In terms of mechanical transmission: When the lifting button is pressed, the controller receives a signal and drives the motor to start working. The motor transmits power to the hook through the transmission mechanism, causing it to begin to rise. During the hook's ascent, it first contacts the hook buffer spring, and the spring's elasticity pushes the rocker arm upward. As the rocker arm moves, it triggers the limit switch contacts, causing the relay in the circuit to operate, thereby cutting off the power and stopping the motor. At this point, the hook stops rising and remains in the preset position.

[0069] When it is necessary to lower the hook, the user can do so by operating the descent button on the controller. Upon receiving the signal, the controller drives the motor in reverse, lowering the hook via the transmission mechanism. During the hook's descent, the limit spring provides auxiliary support, ensuring the rocker arm can smoothly return to its original position. When the hook reaches the preset position, the controller cuts off the power and stops the motor.

[0070] Regarding circuit control: The circuit control section of this low-headroom hoist employs a series circuit and a redundant control mechanism to achieve precise control of the lifting action. When the lifting button is pressed, the circuit is connected and the motor starts working. Simultaneously, the contacts of the limit switches on both sides are closed. When the hook rises and triggers either limit switch, the contact of that limit switch breaks the circuit and stops the motor. At this point, the hook stops rising and remains in the preset position. If one limit switch fails (e.g., due to contact damage or circuit fault), the other limit switch can still function normally and trigger the circuit control. This redundant control mechanism ensures that even if one limit switch fails, the equipment can still control the lifting action normally and avoid accidents.

[0071] The beneficial effects of this utility model, through the design of the above embodiments, are as follows: By creating a rocker installation space within the low-headroom bracket, fabricating the rocker, and integrating the limit switch activation structure into the bracket, the industry-standard structure is raised, saving 100mm of usable space; during use, the hook moves upward, and through the hook buffer spring, pushes the rocker to activate the limit switches on both sides (the limit switches on both sides are connected in series with the lifting button), disconnecting the circuit and stopping the lifting action. Even if one side of the limit switch fails to function, the control system can still perform normal control of the lifting action, increasing the safety of the overall operating system; while improving space utilization, it ensures the safety and reliability of the lifting action; it not only has the characteristics of compact structure and small space occupation, but also has high reliability and safety, providing an effective solution for lifting operations in low-headroom locations.

[0072] This utility model has been described based on specific embodiments, but those skilled in the art will understand that various changes and equivalent substitutions can be made without departing from the scope of this utility model. Furthermore, to adapt to specific applications of this utility model, numerous modifications can be made without departing from its protection scope. Therefore, this utility model is not limited to the specific embodiments disclosed herein, but includes all embodiments falling within the protection scope of the claims.

Claims

1. A low headroom gourd, characterized in that, include: The system includes a limit switch, a rocker arm, a hook buffer spring, a limit spring, and a low headroom bracket. The limit switch is integrated into the low headroom bracket and works in conjunction with the rocker arm. The limit switch is used to detect the hook position. The rocker arm connects the limit switch and the hook buffer spring. The hook buffer spring reduces the impact force on the rocker arm during the hook's ascent, thus protecting the limit switch and rocker arm from damage. The limit spring provides a restoring force to the rocker arm when the hook descends to a preset position, allowing it to return to its initial position. The limit spring is located below the rocker arm and connected to the low headroom bracket. The low headroom bracket supports and secures the limit switch, the rocker arm, the hook buffer spring, and the limit spring.

2. The low headroom hoist according to claim 1, characterized in that, It also includes a control circuit for controlling the lifting of the low headroom hoist.

3. The low headroom hoist according to claim 1, characterized in that, The rocker is made of metal.

4. The low headroom hoist according to claim 2, characterized in that, The control circuit includes a power module, a lifting button, a limit switch, and a controller that are electrically connected.

5. The low headroom hoist according to claim 4, characterized in that, The power module includes an overload protection circuit and a short-circuit protection circuit.

6. The low headroom hoist according to claim 4, characterized in that, The controller includes a programmable logic controller.

7. The low headroom hoist according to claim 4, characterized in that, The controller includes a fault detection module.

8. The low headroom hoist according to claim 4, characterized in that, The controller includes an alarm module.

9. The low headroom hoist according to claim 5, characterized in that, The overload protection circuit includes: a fuse, a thermal relay, an electronic overload relay, a current transformer, a circuit breaker, and a sampling resistor connected in series.

10. The low headroom hoist according to claim 5, characterized in that, The short-circuit protection circuit includes: an automatic air switch, an overcurrent relay, and a transistor. The automatic air switch and the overcurrent relay are connected in series, and then connected in parallel with the transistor.

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