The utility model relates to a high viscosity filter cake can be effectively improved on the filter cloth and the automatic cake mechanism of scraping of pressure filter of quality is rooted out, including the shovel cake frame and shovel cake frame actuating mechanism that is n -shaped, be connected on shovel cake frame actuating mechanism puts up with the shovel cake and drive shovel cake frame and reciprocate, shovel cake frame both sides pole lower extreme is equipped with flexible shovel no. 1 respectively and vertically is equipped with filter cloth backup pad no. 1 and filter cloth backup pad no. 2 with flexible shovel no. 2 and in shoveling the cake frame, and the shovel head of flexible shovel no. 1 supports the lower extreme outside of leaning on filter cloth backup pad no. 1 and supports the lower extreme outside of leaning on filter cloth backup pad no. 2 along the shovel head of, flexible shovel no. 2 and follow when flexible shovel no. 1 and flexible shovel no. 2 are in shovel pie attitude. The advantage: automatic cake mechanism of scraping of pressure filter on rooting out the filter cloth during high viscosity filter cake filter cloth backup pad among the automatic cake mechanism of scraping of pressure filter will prevent that the filter cloth bullet from rising to the quality of driving of on filter cloth high viscosity filter cake has been improved.