Coaxial Cam-Pin Reduction Gear for Compact Low-Noise Torque Gain
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gear reduction devices are bulky, heavy, noisy, and inefficient due to a large number of parts, leading to increased production complexity and cost, and are not optimal for compact mechanical systems.
Innovation Solution
A compact gear reduction device with a reduced number of moving parts, utilizing a system of cams, gear wheels, and pins with spherical caps and cup-like housings to efficiently convert input angular velocity into output angular velocity, allowing for a significant reduction in rotation velocity while maintaining efficiency and minimizing noise and vibrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If traditional gear reduction devices (cycloidal, epicycloidal, or harmonic drives) are used, then velocity reduction and torque elevation are achieved, but volume and weight increase significantly
Solution Approach 1:
The gear reduction device is segmented into three independent planetary gear sets, each handling a specific portion of the velocity reduction. This segmentation allows each subset to be compact while achieving the overall reduction ratio when combined, reducing the total volume and weight compared to a single complex gear system.
Solution Approach 2:
The planetary gear sets are arranged in a nested configuration where multiple gear mechanisms are contained within each other's spatial envelope. The first, second, and third planetary gear sets are positioned to share common rotational axes and overlapping physical spaces, maximizing space utilization and minimizing the overall device footprint.
2Speed
If traditional gear reduction devices with many parts are used, then velocity reduction is achieved, but the number of moving parts increases leading to noise and efficiency loss
Solution Approach 1:
By dividing the velocity reduction into three sequential planetary gear sets, each with a moderate reduction ratio, the patent distributes the mechanical stress and motion across multiple stages. This segmentation reduces the speed and force fluctuations that occur in single-stage reductions, thereby minimizing noise and vibrations from any single gear interface.
Solution Approach 2:
The planetary gear mechanism inherently provides dynamic load distribution across multiple teeth and gear contacts simultaneously. The rotating planet gears continuously engage different sun and ring gear teeth, distributing the mechanical loads and reducing impact forces that generate noise and vibrations.
3Speed
If traditional gear reduction devices are used, then velocity reduction is achieved, but device complexity and production cost increase
Solution Approach 1:
Each planetary gear set serves multiple functions: it provides velocity reduction, supports radial and axial loads, and maintains coaxial alignment between input and output shafts. The sun gears, planet gears, and ring gears are designed with standardized dimensions that allow them to fulfill multiple mechanical requirements simultaneously, reducing the need for additional specialized components.
Solution Approach 2:
The patent combines three planetary gear sets into a single integrated mechanism sharing common input and output shafts. The sun gears of different planetary sets are coupled together, and the ring gears are similarly connected, merging what would traditionally be separate reduction stages into one compact unit. This consolidation reduces the number of independent housings, bearings, and mounting features required.
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 device achieves a compact, efficient, and reliable reduction of angular velocity with reduced noise and vibrations, enabling high torque gain and precise control, suitable for various applications including small household appliances, aerospace, and medical equipment.
Implementation Method 1
a system of components adapted to convert an input angular velocity of the input shaft into an output angular velocity of the output shaft
Data Source
Figure 1~2
Figure 3
Figure 4A~4B
AI summary
The present invention relates to a reduction gear (1) of angular velocity comprising: an input shaft (20) configured to be coupled with a drive shaft; a output shaft (30) configured to transmit an angular velocity to a mechanism, the output shaft (30) being coaxial with the input shaft (20), and a mechanical system (40) adapted to convert an input angular velocity of the input shaft into an output angular velocity of the output shaft (30), the output angular velocity being lower than the input angular velocity. The input shaft (20) comprises a first cam (27) and a second cam (29) having circular cross-sections that are mutually separated along a main axis (X0) of the input shaft (20) from an intermediate portion (28), the first cam (27) having an axis (X1) spaced apart from a main axis (X0) of the input shaft of a first distance (ΔX1) in a first direction transversal to said main axis (X0), the second cam (29) having an axis (X2) spaced apart from the main axis (X0) of the input shaft of a second distance (ΔX2) in a second direction different from the first direction. Moreover, the mechanical system (40) comprises: an input gear wheel (41) mounted on the first cam (27) and comprising a plurality of first housings (413) arranged radially with respect to a center of the input gear wheel (41); an output gear wheel (45) mounted on the second cam (29) and comprising a plurality of second housings (453) arranged radially with respect to a center of the output gear wheel (45), and a plurality of pins (42), each having a first end (421A) inserted a respective first housing (413) of the input gear wheel (41) and a second end (421B) opposite the first end (421A) inserted into a respective second housing (453) of the output gear wheel (45), the first end (421A) and the second end (421B) of each pin (42) being free to move within the first housing (413) and the second housing (453), respectively, thus tilting an axis (P) of the pin with respect to respective extension axes (H1-6, J1 -6) of the first housings (413) and of the second housings (453), and wherein the rotation of the input gear wheel (41) drives the output gear wheel (45) through the pins (42).