Pivotal Backrest Squat Machine for Knee Shear Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional squat machines limit hip motion, cause knee shear, and result in spinal compression, posing safety concerns and reducing exercise effectiveness, especially in rehabilitation settings where full range of motion and user orientation are crucial.
Innovation Solution
A squat machine design featuring a rigidly mounted foot plate, pivotally connected backrest, and a parallelogram frame assembly that allows full hip motion, minimizes knee shear by maintaining the knee behind the toes, and reduces spinal compression by distributing resistance through a horizontal arc, accommodating one-legged squats and adjustable components for user comfort and safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional squat machines are used, then safety is improved by eliminating free weight risks, but hip motion is limited and knee shear may occur
Solution Approach 1:
The backrest is made pivotal rather than fixed, allowing it to move dynamically between a first position (providing support) and a second position (allowing full hip motion). This dynamic adjustment resolves the contradiction by adapting the support mechanism to different phases of the squat movement, maintaining safety while enabling full range of motion.
Solution Approach 2:
The squat machine is divided into functionally independent segments: a fixed foot plate for stable base support, a pivotal backrest for adjustable back support, and a resistance mechanism that moves independently. This segmentation allows each component to optimize its function without compromising others, enabling full hip motion while maintaining safety through specialized support elements.
2Reliability
If conventional squat machines are used, then safety is improved, but knee shear may result from knee movement beyond toes
Solution Approach 1:
The pivotal backrest acts as an intermediary mechanism between the user's body and the resistance force. It mediates the squatting motion by providing dynamic support that guides the knee behind the toes throughout the movement range, preventing knee shear while allowing full hip motion. The backrest intermediates the force transmission to eliminate harmful knee shear.
3Reliability
If conventional squat machines are used, then safety is improved, but spinal compression occurs from weight load
Solution Approach 1:
The resistance mechanism uses a counterbalancing design where the resistance force is applied through a pivotal backrest system that offsets the user's body weight. The resistance member and pivot arrangement create a counterweight effect that distributes the load away from the spine, reducing spinal compression while maintaining safety through controlled resistance.
4Adaptability or versatility
If squat machines orient user in standing position, then body weight is included in exercise, but this is undesirable in rehabilitative therapy
Solution Approach 1:
The pivotal backrest enables the machine to adapt between different user orientations. In a standing position, the backrest provides support to reduce body weight impact. In a horizontal position, the backrest can be positioned to provide full support, eliminating body weight from the exercise. This dynamic adaptability allows the machine to serve both strength training and rehabilitative therapy needs.
Data Source
AI summary
The squat machine of the present invention includes a base having opposite sides, a stationary foot plate fixed on the base, a pair of frames each pivotally mounted to respective sides of the base, and a back rest pivotally mounted to the frames so that the frames and back rests are moveable between an initial squat position and an extended position. The back rest is oriented at approximately a 45°-60° angle in the squat position and moves toward a substantially horizontal orientation in the extended position. In use, with proportional foot platement on the foot plate, the user's knees remain behind their toes throughout full range of motion through the hips during movement of the back rest so as to minimize risk of knee shear. The orientation of the back rest minimizes risk of spinal compression during use of the machine.