Keyboard Instrument Lid Mechanism for Compact Stability
Solution Overview
Problem
Conventional keyboard musical instrument lid opening/closing mechanisms either require additional space for the lid's rear end, increasing the instrument's size and complexity, or result in a large displacement of the lid's center of gravity, leading to unstable operation and risk of user injury.
Innovation Solution
A lid opening/closing mechanism where the lid's rear end slides from the rear to the front and upward during opening, using a connecting mechanism with pivotally-supported members and a slide mechanism that reduces the number of components and stabilizes the lid's movement, ensuring a compact and safe operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the lid is accommodated in the instrument main body during opening/closing, then the clearance between the lid and top plate is minimized, but the instrument main body size increases and the connecting mechanism becomes complicated
Solution Approach 1:
The connecting mechanism is divided into multiple functional components: a link member with first and second link portions connected by a rotationally movable joint, and a guide abutment member with guide portions. This segmentation allows each component to perform a specific function (rotation, guidance, constraint) independently, achieving precise lid movement control while maintaining a relatively simple overall structure that does not require complete lid accommodation.
2Manufacturing precision
If the lid is accommodated in the instrument main body, then the clearance is minimized, but the space required for pivotal movement increases
Solution Approach 1:
The guide abutment member acts as an intermediary between the lid and the instrument main body. Its guide portions (first and second guide portions) provide controlled pathways that constrain the lid's movement trajectory during opening/closing. This intermediary structure enables precise clearance control while minimizing the overall pivotal movement space required, as the guide portions direct the lid's motion efficiently without requiring large accommodation spaces.
3Device complexity
If the lid pivots about the rear end portion, then the structure is simplified, but the center of gravity displacement becomes large causing unstable operation
Solution Approach 1:
The connecting mechanism transitions from a simple fixed pivot to a dynamic multi-degree-of-freedom system. The link member can rotate at the joint between its first and second portions, and the guide abutment member provides constrained guidance. This dynamic structure allows the lid's center of gravity to move more smoothly and predictably during opening/closing, reducing abrupt displacement and improving operational stability while maintaining reasonable structural simplicity.
4Stability of the object's composition
If the lid is connected with multiple components, then the movement is stabilized, but the number of components increases
Solution Approach 1:
The connecting mechanism merges multiple functions into integrated components. The link member combines rotation capability (through the rotationally movable joint) with structural support functions. The guide abutment member combines guidance (through multiple guide portions) with constraint functions. This merging approach stabilizes lid movement through coordinated action of these multi-functional components while avoiding an excessive increase in the total number of separate parts.
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 mechanism allows for easy and stable opening/closing of the lid, minimizing the instrument's size and preventing user injury by reducing the lid's center of gravity displacement and avoiding abrupt posture changes.
Implementation Method 1
a rotationally movable joint (532, 542) configured to generate a resistance force against relative rotation
Implementation Method 2
a resistance-force generating portion configured to generate a resistance force against relative rotation of the main body and the connecting member and relative rotation of the lid and the connecting member
Data Source
AI summary
A lid opening/closing mechanism for a keyboard musical instrument, including: a main body including a casing and a keyboard; a lid attached to the casing so as to be movable between a closed position for covering the keyboard and an open position for uncovering the keyboard; and a connecting mechanism for connecting a side wall portion in the casing and an end portion of the lid and opposed to the side wall portion, wherein the connecting mechanism is configured such that, during a movement of the lid from the closed position to the open position, a rear end portion of the lid slidingly moves only in a direction from a rear end portion of the main body toward a front end portion thereof or moves in the direction from the rear end portion of the main body toward the front end portion thereof and in an upward direction.