1. Definition and basic principle of worm reduction gearbox
A worm reduction gearbox is a mechanical device that uses the meshing transmission of a worm and a worm wheel to achieve speed reduction. The worm is similar to a screw and has a large lead angle, while the worm wheel is a gear with a special shape. When the worm rotates, the power is transmitted to the worm wheel through the interaction between the helical tooth surface of the worm and the tooth surface of the worm wheel, thereby achieving speed reduction.
2. Main components of worm reduction gearbox
1. Worm and worm wheel: The core transmission components of worm reduction gearbox are worm and worm wheel. The worm is similar to a screw and has a large lead angle, while the worm wheel is a gear with a special shape. They achieve speed reduction through meshing transmission. When the worm rotates, the power is transmitted to the worm wheel through the interaction between the helical tooth surface of the worm and the tooth surface of the worm wheel, thereby achieving speed reduction.
2. Bearings and shafts: The main functions of bearings and shafts are to support and fix gears, reduce friction and wear, and ensure smooth operation of shafts. The parts on the shaft are fixed axially by the shaft shoulder, sleeve and bearing cover. Deep groove ball bearings are usually used to bear radial loads and small axial loads. When the axial load is large, angular contact ball bearings, tapered roller bearings or a combination of deep groove ball bearings and thrust bearings will be used.
3. Housing: The housing is the main component of the reducer, providing support and protection, accommodating internal components, and ensuring good lubrication and sealing. The housing is usually made of gray cast iron, and cast steel housing can also be used for reducers with heavy loads or impact loads. The housing is made horizontally split along the axis, and the upper housing cover and the lower housing are bolted together.
4. Lubrication and sealing system: The lubrication system ensures that the gears and bearings are fully lubricated to prevent the loss of lubricating oil and the entry of external impurities. The sealing element is used to prevent the leakage of lubricating oil and the entry of external dust into the housing to ensure the normal operation of the reducer.
3. Structural advantages of worm reduction gearbox
1. Compact structure: The worm reduction gearbox can achieve a larger transmission ratio in a smaller space through the line contact meshing of the worm and the worm wheel. This makes the worm reduction gearbox more compact in structure and suitable for space-constrained occasions, such as elevator traction systems, AGV logistics vehicles and medical equipment.
2. Large transmission ratio: The worm reduction gearbox can achieve a larger transmission ratio, usually 5:1 to 100:1, or even higher. This enables the worm reduction gearbox to achieve a larger speed reduction in a smaller space and meet the needs of different equipment.
3. Smooth transmission: The transmission process of the worm reduction gearbox is relatively smooth, with low noise and low vibration. The meshing of the worm wheel and the worm is continuous, without the impact and vibration in the gear transmission, and is suitable for use in occasions requiring low noise and high stability, such as precision instruments and equipment and textile machinery.
4. Reverse self-locking: When the lead angle of the worm is less than the friction angle, the worm reduction gearbox has the self-locking function of irreversible transmission. This feature is very useful in situations where reversal needs to be prevented, such as crane hooks and automated warehouse lifting mechanisms, which can achieve mechanical self-locking in the power-off state to prevent the load from slipping.
5. Low noise: The noise of the worm reduction gearbox is lower than that of the gear reducer. The meshing of the worm wheel and the worm is multi-point contact, and the load is evenly distributed on multiple contact points, reducing stress concentration and thus reducing noise.
6. Strong load-bearing capacity: The worm wheel and worm of the worm reduction gearbox are usually made of high-strength materials, and are precision machined and heat-treated, with strong load-bearing capacity. It can withstand large loads and is suitable for situations where large torque needs to be transmitted.
4. Selection criteria for worm reduction gearbox
1. Transmission ratio and speed ratio calculation: The ideal reduction ratio needs to be calculated when selecting. The calculation formula for the reduction ratio is: reduction ratio = motor speed (standard speed 1400 rpm) / speed of the output shaft of the reducer. Selecting a model close to the ideal reduction ratio can improve the efficiency and life of the reducer.
2. Torque calculation: Torque calculation is crucial to the life of the reducer. It is necessary to ensure that the maximum load torque of the reducer is not less than the required maximum torque value to avoid overload damage.
3. Load type and duty: Select a suitable reducer according to the load type (constant torque, variable load or impact load) and duty (continuous operation or intermittent operation). For example, for applications that require frequent starting and stopping, it is more appropriate to select a reducer with a higher safety factor.
4. Environmental conditions: Consider the use environment (such as outdoor, high temperature, dust, etc.) to select a reducer with a corresponding protection level (such as IP65) or special coating to ensure its reliable operation in harsh environments.
5. Lubrication method: Select the lubrication method according to the working conditions. By default, grease lubrication is used, but forced oil lubrication can be selected under high speed or high temperature conditions.
6. Installation method: Select different installation methods such as foot installation, flange installation or shaft installation according to the installation space.
7. Maintenance and troubleshooting: Understand the maintenance cycle of the reducer and common troubleshooting methods, such as regularly checking the oil level and sealing, and regularly changing the lubricating oil, etc.
Posted
May 10 2025, 01:35 AM
by
Randy45