A resilient-support adjusting device of a chair backrest includes a base and a spring-tensioning brace and a backrest-fastening seat pivotally connected to two ends of the base. The backrest is fixed to the backrest-fastening seat. A spring is tensioned between the spring-tensioning brace and the backrest-fastening seat. The base contains upper and lower abutting members that have inclined abutting surfaces abutting against each other. The upper abutting member has an upper end abutting against a swinging end of the spring-tensioning brace. The lower abutting member has an engaging member that can be driven by the operating lever to rotate. The engaging member and the lower abutting member engage with each other. When rotated, the operating lever drives the spring-tensioning brace to swing and draw the spring. The spring thus draws the backrest-fastening seat harder, making the backrest have stronger backward resilient support.
Resilient-support adjusting device of chair backrest
2016-01-26
Patent
Electronic Resource
English