Rotational Variation Damper Buffer Structure for Torque and Vibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional rotational fluctuation absorbing dampers in motor vehicles experience reduced vibration preventing performance and torque transmission when starting an engine with a great torque, leading to hammering sounds and potential durability issues due to excessive deformation of coupling rubber, especially in idling stop vehicles where the alternator generates power to start the engine.
Innovation Solution
The rotational fluctuation absorbing damper incorporates a coupling rubber with a low twisting direction spring constant and buffer portions with first and second projections that compress when relative displacement exceeds a predetermined value, providing a nonlinear increase in spring constant to prevent excessive deformation and maintain torque transmission while avoiding size enlargement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the twisting direction spring constant of the coupling rubber is made low to improve rotational fluctuation absorption performance, then the vibration damping function is improved, but the durability of the coupling rubber is lowered and it becomes easily broken
Solution Approach 1:
The patent applies beforehand cushioning by providing a stopper mechanism that prevents excessive deformation of the coupling rubber before it can break. The stopper mechanism includes a stopper member with a stopper surface that contacts the coupling rubber when relative displacement reaches a predetermined amount, cushioning the excessive deformation and preventing rubber breakage while maintaining low spring constant for vibration damping
2Strength
If the stopper mechanism is designed to prevent excessive deformation of the coupling rubber, then the durability is improved, but the device complexity increases
Solution Approach 1:
The patent merges the stopper mechanism with the existing hub and pulley main body structures. The stopper member is integrated into the hub, and the stopper surface is formed on the pulley main body, combining multiple functions into existing components rather than adding entirely separate mechanisms, thereby reducing overall device complexity
Solution Approach 2:
The stopper member serves multiple functions: it acts as both a structural component of the hub and a stopper mechanism component. The same component provides both rotational support and excessive deformation prevention, reducing the total number of parts and simplifying the overall structure
3Reliability
If the stopper mechanism uses metal contact to maintain torque transmission when coupling rubber breaks, then the torque transmission function is maintained, but hammering sounds are generated and vibration preventing performance deteriorates
Solution Approach 1:
The patent uses an intermediary approach by designing the stopper mechanism to contact the coupling rubber itself rather than allowing direct metal-to-metal contact. The stopper surface contacts the coupling rubber to prevent excessive deformation, using the rubber as an intermediary that absorbs vibrations and eliminates hammering sounds while still maintaining torque transmission function
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design effectively suppresses excessive deformation of the coupling rubber, enhances vibration preventing performance, and improves torque transmission force without increasing the damper's size, ensuring quiet operation and durability.
Implementation Method 1
transmits the torque input to the hub 110 from the crank shaft to the pulley main body 131 while absorbing the rotational fluctuation on the basis of a twisting direction shear deforming action of the coupling rubber 133
Implementation Method 2
the dynamic vibration absorbing portion 120 formed by a spring-mass system constructed by the damper rubber 121 and the annular mass body 122 resonates in a twisting direction with a resonation frequency range of the crank shaft, thereby achieving a vibration damping function of dynamically absorbing the resonance of the crank shaft
Implementation Method 3
an outer tube portion 111 of the hub 110 and an annular mass body 122 arranged in an outer periphery thereof is elastically coupled via a damper rubber 121
Implementation Method 4
the buffer portions of the coupling rubber are compressed by the first projections of the hub and the second projections of the pulley main body which are brought into contact with the buffer portions from both sides in the circumferential direction
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is a damper for absorbing a rotational variation, the damper having improved torque transmission ability and vibration damping performance, which are achieved without increasing the size of the damper. This damper for absorbing a rotational variation is provided with: a hub (10); a pulley body (31) disposed so as to be coaxial with and rotatable relative to the hub (10); and coupling rubber (32) for connecting the hub (10) side and the pulley body (31) side so that the hub (10) and the pulley body (31) can be circumferentially displaced relative to each other. The hub (10) has a plurality of first projections (15) provided at predetermined circumferential intervals. The pulley body (31) has a plurality of second projections (36) provided at predetermined circumferential intervals so as to be located between the first projections (15). The coupling rubber (32) has formed thereon buffer sections (321) located between the first projections (15) and the second projections (36). When the amount of relative circumferential displacement between the hub (10) and the pulley body (31) is greater than or equal to a predetermined value, the first projections (15) and the second projections (36) are in contact with the buffer sections (321) from both circumferential sides.