Rotary Encoder Wedge Cam Clamping Mechanism

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing rotary encoders require a large amount of radial space for actuation due to the axial distance locking mechanism, which is inefficient and prone to misadjustment during transport.

Innovation Solution

A rotary encoder design featuring a wedge-shaped element and cam mechanism that allows for secure clamping and precise adjustment of the axial distance between the detector arrangement and code disk, enabling compact space usage and maintaining precise alignment during transport and installation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a bow-shaped element with radial longitudinal displacement is used to lock axial distance, then the axial distance can be locked, but a large amount of radial space is required

Engineering Contradiction:
Improveaxial distance lockingVSAvoidradial space
Core Design Contradiction:
ReliabilityVSArea of moving object

Solution Approach 1:

The invention transitions from radial displacement (bow-shaped element) to axial displacement (cam mechanism) for achieving the locking function. The cam mechanism moves axially along the shaft to compress the wedge-shaped element, thereby locking the axial distance between code disk and detector arrangement, eliminating the need for radial space expansion.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

Instead of using a bow-shaped element that expands radially to lock the axial distance, the invention inverts the approach by using an axially moving cam mechanism that compresses a wedge-shaped element radially inward to achieve the same locking effect, thus solving the space contradiction.

Inventive Principle:
Principle #13The other way round (Inversion)

2Ease of operation

If the axial distance is not locked, then the device is easy to adjust, but misadjustment occurs during transport

Engineering Contradiction:
ImproveadjustabilityVSAvoidalignment stability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The clamping ring can be rotated to different positions: when the cam mechanism is in the released position, the wedge-shaped element is not compressed, allowing axial adjustment; when rotated to the engaged position, the cam compresses the wedge-shaped element to lock the axial distance, preventing misadjustment during transport. This dynamic switching between adjustable and locked states resolves the contradiction.

Inventive Principle:
Principle #15Dynamics

3Ease of operation

If a bearing is used to support rotation, then rotation is smooth, but the device complexity increases

Engineering Contradiction:
Improverotation smoothnessVSAvoidbearing structure
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The shaft itself serves as the bearing surface through its cylindrical geometry and friction fit with the wedge-shaped element. The wedge-shaped element, when compressed by the cam, creates frictional contact with the shaft surface that provides both support and smooth rotation without requiring separate bearing components, thus reducing device complexity while maintaining rotational performance.

Inventive Principle:
Principle #25Self-service

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 allows for a compact, space-efficient design that maintains precise axial distance and centering, ensuring reliable operation and easy installation while preventing misadjustment during transport and operation.

Implementation Method 1

a clamping ring (12) with at least one cam (12.2)... By rotating the clamping ring (12) relative to the housing part (11.1), a force with a radial directional component oriented towards the axis can be introduced via the at least one cam (12.2) onto the at least one wedge-shaped element (11.12)

Methodology Applied
Scientific EffectCam mechanism: Cam

Implementation Method 2

a housing part (11.1) with at least one wedge-shaped element (11.12)... the surfaces of the wedge-shaped elements (11.12) facing the shaft (21) being configured in a concavely curved manner... the shaft (21) can be clamped on the housing part (11.1) by means of a friction fit

Methodology Applied
Scientific EffectWedge mechanism: Wedge

Implementation Method 3

When a temporally changing electric excitation field is applied to the excitation coils, signals dependent on the angular position are generated in the receiver coils during the relative rotation between rotor and stator

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP1927823B1Rotary encoder
Publication Date: 2013.03.27 DR JOHANNES HEIDENHAIN GMBH
  • EP1927823B1 patent drawingFigure 1~2
  • EP1927823B1 patent drawingFigure 3~4
  • EP1927823B1 patent drawingFigure 5a~5b

AI summary

The invention relates to a rotary encoder comprising a first component group (10) and a second component group (20), wherein, in a measuring operation, the two component groups (10, 20) are rotatably arranged relative to each other. The first component group (10) comprises a detector arrangement (13), a housing part (11.1) with at least one wedge-shaped element (11.12), and a clamping ring (12) with at least one cam (12.1). The second component group (20) comprises a code disk (23) and a shaft (21). The housing part (11.1) is arranged radially outside the shaft (21) and can be clamped to the housing part (11.1) by means of a rotational movement of the clamping ring (12) relative to the housing part (11.1), via which at least one cam (12.1) can introduce a force with a radial directional component oriented towards the axis (A) onto the at least one wedge-shaped element (11.12), so that the shaft (21) can be clamped to the housing part (11.1) outside of the measuring operation.