Encoder Readhead Light Emitter Support Structure

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing encoder apparatuses, particularly absolute encoders, face challenges in reducing the size and cost while maintaining effective optical configurations, as the light emitting elements are typically mounted directly on the circuit board, limiting the range of optical configurations and increasing the number of optical components needed.

Innovation Solution

The encoder apparatus features a light emitting element support structure that holds the light emitting element away from the circuit board and sensor, using a folded sheet-material structure to create a three-dimensional frame, allowing the light emitting element to be positioned between the sensor and other optical components, thereby reducing the number of optical components required and enabling a more compact design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If the light emitting element is mounted directly on the circuit board, then the device complexity is reduced, but the optical configuration flexibility is limited and the number of optical components increases

Engineering Contradiction:
Improvedevice complexityVSAvoidoptical configuration flexibility
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The light emitting element is mounted on a support structure that extends in the vertical dimension away from the circuit board, transitioning from a two-dimensional board surface to a three-dimensional spatial arrangement. This enables the light emitting element to be positioned between the sensor and other optical components, creating new optical configurations without increasing device complexity.

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

2Ease of manufacture

If the light emitting element is mounted directly on the circuit board, then the manufacturing cost is reduced, but the number of optical components increases

Engineering Contradiction:
Improvemanufacturing costVSAvoidnumber of optical components
Core Design Contradiction:
Ease of manufactureVSQuantity of substance

Solution Approach 1:

The support structure serves multiple functions: it provides mechanical mounting for the light emitting element, positions it in the optical path between the sensor and other optical components, and reduces the total number of optical components needed. By combining structural and optical functions, manufacturing cost is reduced while component quantity decreases.

Inventive Principle:
Principle #5Merging (Combining)

3Volume of moving object

If the light emitting element is positioned close to the sensor, then the readhead size is reduced, but the optical configuration options are limited

Engineering Contradiction:
Improvereadhead sizeVSAvoidoptical configuration options
Core Design Contradiction:
Volume of moving objectVSAdaptability or versatility

Solution Approach 1:

The support structure utilizes the vertical dimension to position the light emitting element away from the circuit board, enabling it to be located between the sensor and other optical components. This three-dimensional arrangement allows for compact readhead design while maintaining multiple optical configuration options.

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

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 reduces the size and cost of the readhead while enabling a range of new optical configurations, improving the encoder's efficiency and accuracy by allowing the light emitting element to be placed in-line with the sensor and lens, reducing noise and increasing photon capture.

Implementation Method 1

a light emitting element... one or more photodiodes for detecting light reflected from a scale

Methodology Applied
Scientific EffectLight emission: Light Emitting Diode

Implementation Method 2

at least one lens... allowing the light emitting element to be placed in-line with the sensor and lens

Methodology Applied
Scientific EffectLight refraction and focusing: Lens

Implementation Method 3

one or more photodiodes for detecting light reflected from a scale

Methodology Applied
Scientific EffectPhotoelectric detection: Photoelectric Effect

Data Source

PatentEP4058757B1Encoder apparatus
Publication Date: 2025.01.01 RENISHAW PLC
  • EP4058757B1 patent drawingFigure 1~2
  • EP4058757B1 patent drawingFigure 3a
  • EP4058757B1 patent drawingFigure 3b

AI summary

An encoder apparatus comprising a readhead for reading a reflective scale located adjacent the readhead. The readhead comprises a circuit board on which a sensor comprising one or more photodiodes for detecting light reflected from a scale located adjacent the readhead is mounted, and at least one light emitting element. The light emitting element is mounted to the circuit board via a light emitting element support structure which holds the light emitting element away from the circuit board and the sensing plane of the sensor, and at least a part of which extends over the sensor.