Rotary Encoder Housing Interference Fit Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotary encoders face challenges in achieving high measurement accuracy while being economically produced and easily installed, particularly in applications requiring precise position information for electric motors.
Innovation Solution
A rotary encoder design featuring a housing with a shaft, a precisely manufactured stop surface for attachment, and a scanning device, utilizing an interference fit between the housing body and cover to achieve precise positioning without mechanical bearings, allowing for high accuracy and simplified installation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If mechanical bearings and compensating couplings are used to ensure precise positioning, then measurement accuracy is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The patent removes mechanical bearings and compensating couplings from the encoder system. Instead of using these traditional mechanical support elements, the encoder leverages the precisely manufactured stop surfaces on the shaft and housing to establish radial and axial positioning directly, eliminating unnecessary mechanical components that increase complexity.
Solution Approach 2:
The patent replaces the mechanical bearing and compensating coupling system with a precision-machined mechanical interface. The stop surfaces on the shaft and housing body provide the necessary positioning and support functions that were traditionally fulfilled by bearings and flexible couplings, achieving the same effect through precision machining rather than separate mechanical components.
2Measurement precision
If precision machining of stop surfaces is performed to achieve accurate positioning, then measurement accuracy is improved, but manufacturing time and cost increase
Solution Approach 1:
The patent combines multiple positioning functions into the stop surfaces that are created during standard encoder manufacturing. The same machining operations that define the encoder's internal geometry also create the precision stop surfaces, eliminating the need for separate precision machining steps and integrating positioning functionality into the base manufacturing process.
3Ease of manufacture
If the housing is designed with a flexible element deformed by interference fit, then ease of assembly is improved, but manufacturing precision requirements increase
Solution Approach 1:
The patent utilizes the elastic deformation of the housing body through controlled interference fit of the cover. The flexible element in the housing undergoes elastic deformation during assembly, allowing for tolerance compensation and simplifying the assembly process while maintaining the necessary positioning accuracy through the elastic recovery and rigid connection once assembled.
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 solution enables high measurement accuracy and cost-effective production, with the rotary encoder achieving precise angular position measurements without the need for compensating couplings, ensuring reliable operation in electric motor applications.
Implementation Method 1
The housing (1) includes a housing body (1.1) and a cover (1.2), which are connected to one another by an interference fit and the housing having a mechanically flexible element which is deformed as a result of the interference fit.
Data Source
Figure 1~2b
Figure 3~4
AI summary
The invention relates to a rotary encoder comprising a housing (1) and a shaft (2) having an axis (A). A indexing disk (2.1) is fixed to the shaft (2) to prevent rotation. The shaft (2) is designed for precise positioning on a first machine part (3.1). Furthermore, a scanning device (1.11) for scanning the indexing disk (2.1) is attached to the housing (1), wherein the housing (1) is designed such that an outer surface (1.13) forms a rigid stop against a second machine part (3.2) with precise radial positioning. The housing (1) comprises a housing body (1.1) and a cover (1.2), wherein the housing body (1.1) and the cover (1.2) are joined together by an interference fit. The housing (1) has a mechanically compliant element (1.12) which is deformed as a result of the interference fit (Figure 1).