pumped back to reservoir 185 through line 238 due to the presence of check valve 239 also the upper end 241 of cylinder 137 cannot draw oil from the reservoir through line 242 due to the presence of check valve 243 in that line once piston 251 has reached the lower end of its travel in cylinder 137 effected because the cylinder is being moved upwardly by link 234 the continued upward movement of link 234 and cylinder 137 drive the upper link 233 upwardly to pivot crank 131 132 counterclockwise and drive mold plate 32 from its discharge position fig3 back to its fill position fig1 the interval of relative movement between cylinder 137 and piston 251 and pumping of hydraulic fluid as described above establishes the necessary dwell period at the discharge position to enable knockout cups 33 to push patties 171 out of mold plate 32 down onto conveyor 172 this completes the mold plate cycle which begins again at the fill position of fig1 from the foregoing description it will be apparent that in each cycle of mold plate 32 a cycle that goes from the top deadcenter position of fig1 and 2 to the bottom deadcenter position of fig3 and 4 and back to the initial top deadcenter position a limited quantity of hydraulic fluid is pumped from reservoir 185 through line 238.