Mechanical pressing machine with dynamic balancing device

A mechanical pressing machine comprising:

• a slider supported on a frame for vertical sliding movement, said slider having an upper press die mounted on its lower surface;
• a pair of sliding blocks mounted respectively on right and left side portions of said frame for horizontal sliding movement;
• a cam follower and a roller follower rotatably mounted on each of said pair of sliding blocks;
• a pair of right and left connecting rods rotatably connected at their one ends to said pair of sliding blocks, respectively, the other ends of said pair of connecting rods being rotatably connected to said slider;
• a balance weight mounted on an upper portion of said frame for vertical sliding movement;
• a first link having one end rotatably connected to each of said pair of sliding blocks for vertical sliding movement through a slide piece, the other end of said first link being rotatably connected to said balance weight;
• a second link having one end rotatably connected to each of said pair of sliding blocks for vertical sliding movement through said slide piece together with said first link, the other end of said second link being rotatably connected to said slider, and said second link having the same length as that of said first link;
• an input shaft rotatably mounted on said frame, said input shaft being connected at its one end to rotation transmission means;
• and
• a rib cam fixedly mounted on the other end portion of said input shaft for rotation therewith, said rib cam having a peripheral portion held between said cam follower and said roller follower on each of said pair of sliding blocks so as to reciprocally move said pair of sliding blocks right and left in a symmetrical manner.