Decelerating Device With Inclined Cylindrical Rollers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing decelerating devices face increased costs and reduced design freedom due to the requirement for high-strength materials and surface hardening treatments in their bearing structures, particularly when using taper roller bearings with integrated inner and outer races.
Innovation Solution
The use of simple cylindrical rollers with inclined axes and sheet metal races instead of taper rollers, allowing for radial and thrust load support with reduced material costs and design complexity, as sheet metal is used for both inner and outer races without the need for bearing steel or surface hardening.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If taper roller bearings with integrated inner and outer races are used, then the bearing can support both radial and thrust loads, but the cost increases and design freedom deteriorates due to requiring high-strength bearing steel and surface hardening treatments
Solution Approach 1:
The bearing is divided into separate components: cylindrical rollers, sheet metal inner race, and sheet metal outer race. This segmentation allows each component to be manufactured independently using cost-effective processes while maintaining the ability to support both radial and thrust loads through proper geometric configuration of the inclined rollers.
Solution Approach 2:
The invention changes the roller shape from tapered to cylindrical, and modifies the contact geometry by inclining the roller axes relative to the bearing axis. This parameter change allows the use of simpler sheet metal races without surface hardening while maintaining load supporting capability through the inclined line contact configuration.
2Strength
If high-strength bearing steel and surface hardening treatments are used, then the bearing has sufficient load withstanding property, but the manufacturing complexity and cost increase
Solution Approach 1:
The invention changes the contact type from point contact to line contact through the use of cylindrical rollers with inclined axes. This parameter change distributes the load over a larger area, reducing the stress concentration that would otherwise require high-strength materials and surface hardening treatments.
Solution Approach 2:
The sheet metal races are designed with specific local geometric features at the contact zones, including the inclination angle of the rollers and the configuration of the rolling surfaces. These local quality enhancements provide sufficient load withstanding capability without requiring overall high-strength materials or surface hardening treatments.
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 configuration results in a low-cost decelerating device with enhanced design freedom, capable of handling large torques at slow rotation speeds while minimizing backlash and overheating risks, and simplifying manufacturing processes.
Implementation Method 1
the cylindrical roller comes into line contact with the rolling surface of the sheet metal
Implementation Method 2
the load withstanding property is large and the backlash is small
Data Source
Figure 1
Figure 2
Figure 3(A)~3(B)
AI summary
A low-cost decelerating device having a high degree of design freedom is obtained. Provided is a decelerating device 2 in which main bearings 18 and 20 are interposed between an output member 16 and fixed members 12 and 14, the decelerating device including: a pair of cylindrical roller rows 60 and 61 which is provided by a back face combination so as to serve as a rolling element of the main bearings 18 and 20 and includes a plurality of cylindrical rollers 60A and 61A having rotation axes 02 and 03 inclined relative to an axis O1 of the output member 16; and sheet metals 62 and 63 which are members forming outer races of the main bearings 18 and 20 and of which both a rolling surface 62A and an opposite rolling surface 62B are parallel to rotation axes 02 and 03 of the cylindrical roller rows 60 and 61.