Leg unit for a wearable sitting posture assisting device

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Solution Overview

Problem

Existing wearable sitting posture assisting devices require complex electronic control systems to manage the blocking mechanism, which can be cumbersome and reduce reliability, and do not allow for easy transition between sitting and standing postures without unblocking the device.

Innovation Solution

A leg unit design featuring a blocking mechanism with an adjustable length that rigidly connects upper and lower supports at specific angles, allowing rotation while blocked, and a guiding mechanism that enables movement without unblocking, simplifying control and maintaining the stored sitting angle for comfort and stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a blocking mechanism is used to maintain sitting posture, then reliability is improved, but device complexity increases due to electronic control requirements

Engineering Contradiction:
ImprovereliabilityVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The guiding means enables the blocking means to maintain its blocked state automatically while allowing necessary movements, eliminating the need for electronic control systems. The mechanical structure itself provides the control function through its geometry and movement constraints, making the system self-regulating and more reliable.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent removes the electronic control unit from the system by designing a guiding means that inherently allows the blocking means to function without electronic intervention. This extraction of the electronic component simplifies the device while maintaining reliability through pure mechanical means.

Inventive Principle:
Principle #2Taking out (Extraction)

2Measurement precision

If electronic control is used to manage blocking mechanism, then control precision is improved, but ease of operation deteriorates due to complex control requirements

Engineering Contradiction:
Improvecontrol precisionVSAvoidease of operation
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The guiding means automatically maintains the blocking means in the blocked state during sitting posture without requiring user intervention or complex control inputs. The mechanical design itself provides the precision control needed, making operation simple and intuitive.

Inventive Principle:
Principle #25Self-service

3Stability of the object's composition

If blocking means rigidly connects supports, then stability is improved, but ease of operation worsens due to inability to rotate while blocked

Engineering Contradiction:
ImprovestabilityVSAvoidease of operation
Core Design Contradiction:
Stability of the object's compositionVSEase of operation

Solution Approach 1:

The guiding means introduces dynamic capability to the blocked state by allowing rotational movement while maintaining the rigid connection for stability. This enables the system to adapt between requiring stability (when blocking is engaged) and requiring movement (when getting up), resolving the contradiction between rigid connection and rotational capability.

Inventive Principle:
Principle #15Dynamics

4Manufacturing precision

If blocking means has fixed length, then manufacturing precision is improved, but adaptability deteriorates due to inability to adjust sitting angle

Engineering Contradiction:
Improvemanufacturing precisionVSAvoidadaptability
Core Design Contradiction:
Manufacturing precisionVSAdaptability or versatility

Solution Approach 1:

The blocking means incorporates an adjustable length mechanism that allows the sitting angle to be modified while maintaining precise manufacturing tolerances. This enables the device to adapt to different user preferences and requirements without sacrificing the structural precision needed for reliable operation.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP3241531A1Leg unit for a wearable sitting posture assisting device
Publication Date: 2017.11.08 CARL STAHL GMBH & CO KG
  • EP3241531A1 patent drawingFigure 1
  • EP3241531A1 patent drawingFigure 2
  • EP3241531A1 patent drawingFigure 3

AI summary

The invention relates to a leg unit (12a, 12'a; 12b, 12'b) for a wearable sitting posture assisting device (10a), comprising an upper support (13a; 13b) designed to receive a weight force of a person (11 a), a lower support (14a; 14b) designed to transmit the person's (11 a) weight force to a ground (15a), a joint (16a; 16b) connecting the at least two supports (13a, 14a; 13b, 14b) to each other, and a blocking means (17a; 17b) implementing a blocked state to block the joint (16a; 16b) at at least one sitting angle (21 a; 21 b) corresponding to an at least partly sitting posture, and comprising a guiding means (29a; 29b) for the blocking means (17a; 17b), which guiding means (29a; 29b) is designed to allow a rotation of the joint (16a; 16b) while the blocking means (17a; 17b) is in the blocked state, to a wearable sitting posture assisting device (10a), comprising two of these leg units (12a, 12'a; 12b, 12'b), and to a method to block such a wearable sitting posture assisting device (10a) in an at least partly sitting posture.