Chair backrest with ventilating function

Abstract

A chair backrest comprises an inner frame, a net, and an outer frame. The inner frame is a hollow member and has an outer peripheral edge. The net is made of soft material and embraces the outer edge of the inner frame. The outer frame is a hollow member made of rigid material and includes a peripheral groove defined in a side thereof and extending along a periphery defining the outer frame. A bottom wall defining the peripheral groove includes a plurality of fastening holes. The outer peripheral edge of the inner frame and an outer peripheral edge of the net are received in the peripheral groove of the outer frame. Fasteners are respectively extended through the fastening holes and into the inner frame.

What is claimed is:  
     
         1 . A chair backrest comprising an inner frame, a net, and an outer frame, the inner frame being a hollow member and having an outer peripheral edge, the net being made of soft material and embracing the outer edge of the inner frame, the outer frame being a hollow member made of rigid material and including a peripheral groove defined in a side thereof and extending along a periphery defining the outer frame, a bottom wall defining the peripheral groove including a plurality of fastening holes, the outer peripheral edge of the inner frame and an outer peripheral edge of the net being received in the peripheral groove of the outer frame, and a plurality of fasteners being respectively extended through the fastening holes and into the inner frame.