Child Swing Drive Mechanism for Adjustable Pendulum Frequency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional child swing apparatuses have fixed swinging frequencies and motion paths, making it difficult to adjust the frequency and requiring high torque for slower pendulum motions, limiting their adaptability and efficiency.
Innovation Solution
A child swing apparatus with a support frame, swing arm, and a drive mechanism that includes a rotary axle and wheel, allowing for adjustable swinging frequencies and motion paths using a smaller torque motor, with the wheel in constant contact with a driven part to impart motion, enabling a range of programmable motions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the drive system is located at the pivot point of the pendulum, then the system can store potential energy between half cycles, but the frequency cannot be adjusted and high torque is required for slower motions
Solution Approach 1:
The patent applies the dynamics principle by making the swing arm length adjustable through a telescopic mechanism. The swing arm can be extended or retracted to change the effective pendulum length, which directly controls the swinging frequency. This dynamic adjustment capability allows the system to adapt to different frequency requirements while maintaining energy storage efficiency through the driven part located at the radial distance from the pivot axis.
2Device complexity
If the swing arm length is fixed, then the structure is simple, but the swinging frequency cannot be adjusted
Solution Approach 1:
The patent implements a telescopic swing arm mechanism that allows dynamic adjustment of the swing arm length. The swing arm includes an extendable portion that can be moved relative to the main swing arm, enabling continuous adjustment of the effective pendulum length. This provides frequency adjustability while maintaining relatively simple structural implementation through guided linear motion and basic mechanical linkages.
3Power
If a smaller torque motor is used, then the device is more efficient, but it cannot overcome gravitational force for slower pendulum motions
Solution Approach 1:
The patent uses the dynamics principle by allowing dynamic adjustment of the swing arm length to optimize the balance between motor torque requirements and desired swinging frequency. By extending the swing arm, the system increases the moment arm for the motor torque, reducing the torque required to achieve the same angular acceleration. This enables smaller torque motors to effectively drive slower pendulum motions while maintaining frequency adjustability.
Solution Approach 2:
The patent applies the dimensionality change principle by introducing a radial dimension for the driven part located at a distance from the pivot axis. This radial positioning creates a mechanical advantage where the motor torque is applied at an optimized lever arm distance, reducing the torque requirement while maintaining control over swinging frequency and motion characteristics.
4Area of stationary object
If the driven part is located at the pivot point, then the drive system is compact, but the frequency range is limited
Solution Approach 1:
The patent applies the dimensionality change principle by positioning the driven part radially outward from the pivot axis rather than at the pivot point itself. This radial positioning in a different spatial dimension allows the drive system to maintain a compact footprint at the pivot while the extended moment arm provides leverage for controlling a broader frequency range. The driven part's radial distance creates a mechanical advantage that expands the operational frequency range without significantly increasing the drive system's footprint.
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 broader range of swinging frequencies and motion paths while using a smaller torque motor, enhancing adaptability and efficiency in simulating natural swinging frequencies and pausing motion as needed.
Implementation Method 1
a wheel in constant contact with the driven part and in constant contact with the board, and the rotation of the wheel can apply a torque on the board to cause swing motion of the seat support
Implementation Method 2
the swinging motion and frequency are generally locked as a function of the length of the swing arm. If a slower frequency is needed along a same motion path, it may be extremely difficult to exert a driving torque for overcoming the gravitational force acting in the pendulum motion
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A child swing apparatus can include a support frame, a seat support for receiving the placement of a child, a swing arm assembled with the support frame about a pivot axis, the swing arm holding the seat support, a driven part arranged radially spaced apart from the pivot axis and movable with the seat support and the swing arm relative to the support frame, and a drive mechanism assembled with the support frame, wherein the drive mechanism has a driving end operable to apply a torque on the driven part to cause swing motion of the seat support.