Apparatus for holding a glass sheet in a substantially vertical position during heat treatment of the glass sheet

In an apparatus for holding a glass sheet in a substantially vertical position having two upright members, a lower crosspiece member and an upper crosspiece member, said crosspiece members joining said upright members, and lower support means on said lower crosspiece member adapted to receive a lower edge of said glass sheet, the improvement comprising upper support means located on said upper crosspiece member which comprises:

• piston means capable of reciprocating movement in a substantially vertical direction for contacting an upper edge of said glass sheet;
• guide means extending in a substantially vertical direction through an aperture defined by said upper crosspiece member for allowing rotational or substantially vertical movement of said piston means;
• and
• means for contacting the sides of said glass sheet operatively associated with said piston means and said guide means, and constructed in a manner such that said contacting means normally remains in an open position, removed from said glass sheet, said open position of said contacting mens corresponding to a raised position of said piston means, and said contacting means assuming a closed position in contact with the sides of said sheet when said piston means moves to a lower position due to a corresponding movement of the upper edge of said glass sheet from bending or sliding of said glass sheet.