Clutches are used to transmit torque in various technical means, equipment and vehicles. This is a connecting device, which is supplied in the form of an independent product, and during operation finds its place in the drive mechanisms. A special representative of this group of engineering parts is a compensating coupling, the range of tasks of which also includes the elimination of displacements during shaft movement.
Purpose of the part
The main objective of this type of coupling is to transfer force from one shaft to another without changing or affecting the dynamics and direction of movement. However, unlike other variations of this device, compensating models additionally provide small angular, radial and axial displacements. What is it for? First of all, this is one of the methods for leveling defects that are present in the design of the shafts themselves, due to which, in principle, an offset occurs. Another purpose of the compensating coupling is to eliminate the effects of displacement and its correction. Even in conditions of compensation for inaccuracies in installation and structural form, some types of mechanism allow shock during the transmission of force. Such devices include a rigid coupling, but elastic modifications soften the moment of translation of the force, supporting the function of correcting the mutual displacement of the shafts.
Technical and operational properties
Of the basic working qualities of the product, which are not directly related to the compensation effect, the following can be distinguished:
- Elasticity. The property of the coupling, aimed at reducing the dynamic loads of rotation in the shaft wire of the machine.
- Torsional stiffness. It is also a kind of elastic properties that can be determined by the ratio of the angle at which the twisting occurs to the torque itself.
- Twist angle. The value expressed by the ratio of the rotation of the coupling half around the circumference under load from torque.
- Damping ability. This quality is most pronounced in a compensating sleeve made of PVC (polyvinyl chloride), which absorbs part of the load energy due to its own temporary deformation. This ability is practically devoid of metal parts.
- Wear resistance. This quality, on the contrary, is distinguished by metal couplings, demonstrating the ability to control the torque under conditions of an increase in the coefficient of friction forces.
Classification by action configuration
On this basis, the following types of compensating couplings are distinguished:
- Radial. A part whose elements (rods, plates, platinum, half couplings) provide compensation for radial displacements along the axes of the working shafts.
- Axial. Coupling models designed to eliminate the effect of axial displacements when connecting shafts.
- Universal. Such parts provide simultaneous compensation of several types of displacements within a single shaft wire.
- Corner In this case, specifically offset angular displacement between the intersecting axes. The effect is achieved due to the angular mobility of the balls located between the coupling halves in special grooves.
Device Application Methods
The general principle of operation of the coupling with the effect of offset compensation is that the elements of the drive coupling half like split sleeves provide sufficient damping force, eliminating distortions. The differences between different approaches to the use of the mechanism are determined by the structural features of the shaft wire, due to which the displacement occurs. In other words, each compensating coupling is integrated into the working group of the shaft so that a certain type of error is eliminated during operation. The design of the coupling itself will be of key importance, but also the method of its placement, which determines the principle of action - spring, disk, articulated, etc.
The use of elastic couplings
One of the most popular types of compensating elements for eliminating bias in the transmission of torque. The standard solution is the use of parts with metal rods, which provide a damping effect due to the bending of cylindrical rods. Such devices integrate into sections of the coupling halves in cylindrical holes. Another type of elastic-compensating couplings - elements with coil springs. Working components are installed between the coupling halves and during the movement provide a damper as a result of compression of the screw metal groups. The springs themselves can be implemented in different ways - for example, they distinguish between serpentine and shaped devices.
Disc compensating mechanisms
In this group, universal and identical couplings are distinguished, which at the same time equally demonstrate the principle of semi-rigid connection of shafts. In the case of a universal mechanism, the compensation of angular, axial and radial deviations as a result of the damping effect of two packages with plates is provided. When displaced, thin-walled metal disks are deformed, which are installed between the coupling halves with a shaft or sleeve. A single compensating coupling with deformation disks focuses only on the elimination of angular displacements. In this configuration, work is performed by active elements from one disk package with thin-walled disks.
Articulated compensating mechanisms
The use of universal and single couplings is also provided, but the principle of their operation is somewhat different. The hinge model is characterized in that instead of the discs and the coupling material itself, special rods demonstrate the bending properties. For example, a universal coupling of this type of method can eliminate both angular and radial displacements, using the energy of a twin fork (rod), which is shifted with respect to the coupling halves. Special elastic articulated mechanisms are also used in technology, which are linear and use bending force of cylindrical rods during operation. In turn, rigid compensating couplings use the mobility energy of ball elements or crosses, which is installed on the perpendicular axes between the coupling halves.
There is also a special group of roller displacement compensation mechanisms in a gross drive. Its distinguishing features include increased elasticity properties, which is caused by the use of rubber cylindrical rollers. They are concentrically located between the protrusions of the coupling halves and thereby provide a fairly tangible coefficient of elastic deformation under compression.
Conclusion
The additional mechanics of action in the gross force transmission system may seem excessive and reduce the working efficiency of the torque in principle. This is partly true and especially in relation to the loads on the coupling, which wears out faster not only due to the expansion of friction zones, but also due to the complexity of the design, which does not add strength to the material. On the other hand, a compensating clutch is an indispensable element if serious displacements are observed in the mating section of the shafts. The reasons for the formation of such flaws are many - from violations in the installation to the presence of defects in the structure itself. The optimal solution to the problem is to eliminate the causes of displacement, but until this moment it is recommended to operate the mechanism with a safety net in the form of a compensating connecting node.