Gear couplings are mechanical devices designed to transmit torque between two shafts that are not perfectly aligned. They typically consist of two flexible joints—one fixed to each shaft—which are connected by a spindle, or third shaft.
A gear coupling is a device designed to connect two shafts at their ends to transmit power. Typically, couplings remain engaged during operation, with some torque limiting couplings designed to slip or disconnect when a torque limit is exceeded to prevent issues.
The primary function of couplings is to join two rotating pieces while accommodating a certain degree of misalignment or movement at one or both ends.
By carefully selecting the coupling based on specific needs and ensuring proper installation, significant reductions in maintenance costs and downtime can be achieved.
Couplings fall into two main categories: Mechanical and Material Flexing. Material flexible types derive their flexibility from compressing and stretching resilient materials such as rubber or flexing thin metallic discs or grids.
Material flexing couplings generally do not require lubrication, with some exceptions for grid couplings. On the other hand, all metal mechanical flexing couplings require lubrication.
In essence, a coupling is a mechanical device that connects the ends of adjacent parts or objects.
Gear couplings are mechanical devices designed to transmit torque between two shafts that are not perfectly aligned. They typically consist of two flexible joints—one fixed to each shaft—which are connected by a spindle, or third shaft. The gear coupling connects the drive motor to the gearbox in hoist mechanisms, but it can also connect the gearbox directly to smaller wire rope drums using a flanged half.
Gear couplings work by connecting two shafts through hubs with external gear teeth attached to each shaft and a flexible sleeve with internal gear teeth that mesh with the hubs. As one shaft rotates, it drives the corresponding hub, causing the flexible sleeve to rotate and transferring torque to the other shaft through the meshing gears. This design allows gear couplings to accommodate misalignment between the shafts while providing efficient torque transmission, making them suitable for heavy-duty industrial applications.
Gear couplings are constructed with a forged sleeve featuring teeth cut on its inside. Typically, these sleeves consist of two parts, each with inward gears. However, in certain cases, the produced sleeve may remain a single piece.
Two center points with outer teeth, containing the same number of teeth as the inner gears, are mounted on the determined and driver shafts separately.
The tooth profile of the outer teeth is often designed to handle heavier loads, and lubrication attachments are strategically placed to ensure proper lubrication at designated intervals.
There are three main types of external teeth used in gear couplings, differing in manufacturing methodology:
Crowning with Variable Radius:
The external teeth are barrel-shaped with a differential radius, significantly increasing the contact area compared to constant radius crowning.
Crowning with Constant Radius:
The external teeth are barrel-shaped with a fixed radius, enhancing the contact area and positioning it closer to the middle portion of the teeth.
Straight Teeth:
The external teeth in the hub are straight, resulting in a line of contact between the external and internal gears if misalignment occurs in the coupling.
Selection for Gear Coupling:
The choice of gear couplings is based on torque ratings, with the following steps:
Determine the torque transmitted by the coupling.
Assess the appropriate service factor based on the application, referring to a provided outline on service factors.
Increase the service factor to handle equivalent torque and select the coupling accordingly.
In the market, various types of couplings are available, each playing a crucial role in different aspects of power transmission. Huading Couplings offers a comprehensive range of power transmission couplings, covering all types to cater to diverse needs in the transmission industry.
Jaw Flex Couplings
Pin and Bush Couplings
Tyre Flex Couplings
Gear Flex Couplings
Grid-Flex Couplings
Sleeve Flex Couplings
Rigid Couplings
Fluid Couplings