Crank Cap Assembly With Rubber-Mass Damping for Front-Back Vibration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing crank cap assemblies do not effectively suppress vibrations in the front-back direction, which contribute to combustion noise in internal combustion engines, as they primarily focus on longitudinal direction resonance suppression.
Innovation Solution
A crank cap assembly featuring a fastening member, a mass member, and elastic rubber members with specific configurations to absorb and dissipate vibrations, including a first rubber part between the fastening member and the mass member, and a second rubber part between the crank cap and the mass member, arranged to align in the mounting direction with a longer length than the cross-sectional maximum, providing elastic support and vibration damping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a connecting rod cap damper is used to suppress resonance in the longitudinal direction, then longitudinal direction resonance is suppressed, but vibration in the front-back direction is not sufficiently suppressed
Solution Approach 1:
The elastic rubber member is divided into a first rubber part and a second rubber part arranged in series in the mounting direction, with each part having specific functions: the first rubber part suppresses vibrations in the mounting direction while the second rubber part suppresses vibrations in the front-back direction. This segmentation allows targeted vibration suppression in different directions simultaneously.
Solution Approach 2:
The invention transitions from suppressing only longitudinal direction resonance to addressing multi-directional vibrations by configuring the elastic rubber member with different length dimensions. The length in the mounting direction is made longer than the maximum length in the cross-section, creating anisotropic vibration suppression characteristics that address both mounting direction and front-back direction vibrations.
2Object-affected harmful factors
If the elastic rubber member has a longer length in the mounting direction than in the cross-section, then front-back direction vibration is suppressed, but the structural complexity increases
Solution Approach 1:
The invention controls the geometric parameters of the elastic rubber member, specifically setting the length in the mounting direction to be longer than the maximum length in the cross-section. This parameter configuration enables the rubber member to exhibit different stiffness characteristics in different directions, achieving front-back vibration suppression through controlled geometric parameters rather than complex structural design.
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
The described configuration effectively reduces vibrations in the front-back direction, thereby minimizing combustion noise and enhancing the overall operational quietness of internal combustion engines.
Implementation Method 1
an elastic rubber member elastically attaching the mass member to the crank cap
Implementation Method 2
The described configuration effectively reduces vibrations in the front-back direction
Data Source
AI summary
A crank cap assembly including a single crank cap rotatably supporting a crankshaft includes: a fastening member fastened to the crank cap, a mass member; and an elastic rubber member elastically attaching the mass member to the crank cap. The elastic rubber member includes a first rubber part arranged between the fastening member and the mass member and a second rubber part arranged between the crank cap and the mass member. The first rubber part and the second rubber part are arranged to be aligned in the mounting direction when attaching the crank cap to an engine body, and the elastic rubber member is formed so that a length in the mounting direction is longer than a maximum length in a cross-section of the elastic rubber member perpendicular to the mounting direction.