Today we will focus on introducing diaphragm couplings, in fact, diaphragm couplings are a kind of flexible couplings with elastic elements.
Figure: Diaphragm coupling of a small engine in a thermal power plant
Diaphragm coupling belongs to metal flexible coupling, which is a transmission device that uses a metal elastic diaphragm as a flexible element to transmit torque.
Its main features:
The transmission torque capacity is large, the diaphragm deformation absorption unit is not aligned, there is no relative movement between the parts, that is, no wear, no noise, long vibration damping life, and no lubrication. Torsional stiffness and critical speed can be adjusted by varying the outer diameter or wall thickness of the intermediate section, thereby improving the torsional vibration characteristics of the unit.
A diaphragm coupling consists of at least one diaphragm and two bushings. The diaphragm is pinned to the bushing and generally does not loosen or cause recoil between the diaphragm and the bushing. Some manufacturers offer two diaphragms and three diaphragms with one or two rigid elements in the middle, which are then attached to the bushing. The difference between a single diaphragm coupling and a double diaphragm coupling is the ability to handle a wide range of deviations, and the single diaphragm coupling is not well adapted to eccentricity due to the need for complex bending of the diaphragm. The double diaphragm coupling, on the other hand, can be bent in different directions at the same time to compensate for eccentricity.
Figure: Diaphragm coupling of a small engine in a thermal power plant
Key features of diaphragm couplings:
1. The ability to compensate for the misalignment of the two axes is strong, the angular displacement can be doubled compared with the toothed coupling, the reaction force is small and the flexibility is large when the radial displacement is large, and a certain axial, radial and angular displacement is allowed.
2. It has obvious shock absorption effect, no noise and no wear.
3. Adapt to high temperature (-80+300) and work in harsh environments, and can operate safely under shock and vibration conditions.
4. High transmission efficiency, up to 99.86%. It is especially suitable for medium and high speed and high-power transmission.
5. Simple structure, light weight, small size, easy to assemble and disassemble. It can be assembled and disassembled without moving the machine (refers to the type with intermediate shaft) and does not require lubrication.
6. It can accurately transmit the speed, and there is no slip in operation, which can be used for the transmission of precision machinery.
