| 摘要 |
<p>The mitred corners of a frame may be reinforced and made more rigid by use of this insert. It is intended for use in frames constructed from hollow plastic sections having welded mitred corners and consists of two solid sections each of which slides in one of the frame sections. The cross section of each part of the insert is trapezoidal and the insert is wedged in position after assembly of the frame, by a key which presses on the inclined face of the insert and on the inside surface of the frame section. If desired, the insert may be an isosceles trapezium in section and have two wedges one on each of the inclined faces.</p> |
