| 摘要 |
The work piece is placed on a carrier plate that rests on grids. The carrier plate needs to be raised from, and lowered onto, the grid at the start and end of the transport operation. This is done by two vertically stacked plates (10,14) separated by inclined linkages (16) with rounded ends engaging similarly rounded bearing surfaces (26a) formed between two straight cuts. In operation the lower plate (10) is supported at its base so that, as the upper plate (14) is pushed to the right, the linkage forces it upward to contact and raise the carrier plate (18). The linkage is taken past its vertical position until its flanks rest on the straight portions of the surface (26a) against which they are pressed by the load. This is then a stable situation and the lower plate can be pushed into the furnace. As the load comes to a stop in the furnace additional force on the lower plate moves it relative to the stationary upper plate so that the load is lowered by a reverse action to that described previously. The lifting pattern can be modified using linkages of different lengths and differently shaped bearing surfaces. |
