Mineral Sizer Coupling Improvement
Introduce
The drum gear coupling, which is responsible for the power transmission between the reducer and the crushing roller, is an important component of mineral sizer. It operates reliably and has a strong load-bearing capacity. It has a small amount of compensation performance and meets the usage conditions of mineral sizer. However, there are still many deficiencies in terms of the convenience of use and the overall security of the system, which urgently need to be improved.
The structure of the drum gear coupling
The drum gear coupling is mainly composed of an inner gear ring, an outer gear sleeve, drum teeth and connecting bolts, etc. The inner gear ring is connected to the output shaft of the reducer, while the outer gear shaft sleeve is fixed to the input shaft of the crushing roller. Power transmission is achieved through the meshing of the drum-shaped teeth. This structure enables the coupling to compensate to a certain extent for the relative displacement between the two shafts of the mineral sizer, reducing the impact of axial, radial and angular deviations caused by installation errors or during operation on power transmission. However, under long-term high-load operation, some of its structures have also exposed some problems such as easy wear and inconvenient maintenance, which need to be further optimized.
Analysis of existing problems
There are many maintenance items and the efficiency is low
When in operation, the coupling of Mineral sizer is subjected to relatively intermittent impact loads. Long-term operation has caused the connecting bolts of the external gear sleeve of the coupling to loosen or even get damaged. During regular maintenance, it is necessary to promptly inspect the connecting bolts. If any are missed or not repaired in a timely manner, the coupling may fail or even be damaged, eventually leading to an accident and shutdown. The drum gear coupling has many failure points, a long maintenance period and a relatively high maintenance cost.
It is not convenient for daily maintenance
When Mineral sizer is undergoing factory tests, the gear roller needs to be rotated to check the meshing condition of the synchronous gears of the coupling. If the meshing does not meet the standards, it needs to be repaired and then tested again until the design requirements are met. During regular maintenance, it is also necessary to rotate the crushing roller to check for faults such as broken teeth, loose teeth, fallen teeth and cracked tooth plates, and quickly carry out repair work such as reinforcing, replacing or welding the components.
Although the hydraulic coupling can be regarded as disconnected when the rotational speed does not meet the conditions or when oil is being drained. However, the toothed roller is directly connected to the output shaft of the reducer. When the toothed roller rotates, the reducer becomes a speed increaser, increasing the difficulty of the toothed roller’s rotation. Only by removing the connecting bolts of the external gear sleeve of the coupling and separating the reducer from the crushing shaft can the crushing roller be smoothly rotated. Due to frequent daily maintenance and repeated disassembly, it is not conducive to the rapid progress of the mineral sizer inspection work.
There are serious safety hazards
During the maintenance process, especially for the crushing chamber of the mineral sizer, since the connection between the output shaft of the reducer and the crushing shaft has not been disconnected, if it is suddenly started at this time, the crushing roller will directly obtain power to rotate, causing a major accident and posing a serious safety hazard. After the oil is drained, although the hydraulic coupling can also completely cut off the power. However, to save maintenance time, the oil drain operation on the coupler is basically not carried out.
Improvement plan
Disengaging drum gear coupling
The improvement plan changes the drum gear coupling to a disengaging drum gear coupling, transforms the original bolted split gear sleeve into an integral gear sleeve, and introduces the relevant design concept of mineral sizer to optimize the structure. The gear sleeve can slide back and forth along the axis of the shaft sleeve. The integral gear sleeve meshes with the left and right shaft sleeves to complete power transmission.
If the integral gear sleeve is slid to the left, it still meshes with the left shaft sleeve but disengages from the right shaft sleeve, cutting off the power transmission. The improved clutch type drum gear coupling has the dual functions of a coupling and a clutch, which can conveniently and quickly achieve power transmission and disconnection, and demonstrates higher stability and adaptability in mineral sizer application scenarios.
Connecting rod design
To cooperate with the use of the new type of coupling, a connecting rod mechanism was designed. The bearing assembly is fixed on the connecting rod bracket. When the coupling rotates, the outer ring of the bearing rolls, drawing on the principle of efficient transmission and friction reduction in mineral sizer. The connecting rod bracket is fixed on the connecting rod base and can rotate around the axis. The handle and the bracket are connected by a key and can be fixed on the handle fixing base with a handle pin.
At this time, the overall gear sleeve is connected to the left and right shaft sleeves to achieve power transmission. Lower the handle and fix it in the pin hole below. The entire gear sleeve will move to the left driven by the connecting rod and detach from the right shaft sleeve, achieving power separation. During the material crushing process of mineral sizer, it can effectively meet the demands of frequent start-stop and power switching.
Analysis of Improvement Effects
（1）Key improvements were made to the external gear sleeve structure, changing the original split structure to an integral design. This significantly reduced the occurrence points of faults, simplified the maintenance process, enhanced maintenance efficiency, effectively shortened the maintenance time, lowered equipment maintenance costs, and improved the reliability and durability of the device. In the integral external gear sleeve, the crushing principle of mineral sizer is integrated to ensure more stable and efficient operation during the mineral processing.
（2）During the test run inspection and daily maintenance by users of the mineral sizer, a new type of connecting rod mechanism control method was adopted. When it is necessary to rotate the crushing roller for inspection or maintenance operations, only the connecting rod mechanism needs to be operated to conveniently separate the crushing shaft from the reducer, quickly completing the detection or daily maintenance work. Not only does it shorten the manufacturing cycle of the crusher production enterprises, enhance production efficiency, but it also reduces the daily maintenance costs and repair time for users.
（3）To further enhance the safety performance of the mineral sizer, a mechanical separation protection device has been added. When the machine is shut down for maintenance, mineral sizer not only automatically cuts off the power supply but also ensures that the machine completely stops running through a mechanical separation device, providing maintenance personnel with dual safety guarantees of power-off and mechanical separation.
Conclusion
Through in-depth analysis and improvement practice of the mineral sizer coupling, the traditional drum gear coupling was successfully upgraded to a disengaged drum gear coupling, and a connecting rod mechanism and mechanical separation protection device were designed as a match. This not only effectively resolves the problems existing in the original coupling, such as low maintenance efficiency, inconvenient daily maintenance and safety hazards, but also significantly enhances the operational stability, maintenance convenience and usage safety of the mineral sizer.
