Apparatus for dieless forming plate materials

A dieless sheet-forming apparatus for progressively forming a sheet into a three-dimensional shape, comprising:

• i. a tool set having a base plate (5), a fixed pressing assembly (6), a sheet holding mechanism (7), a sheet restraining mechanism (7d) and a balanced movement mechanism (9),
• the fixed pressing assembly (6) being provided on the base plate (5) and having a stand (6a) erected on the base plate (5) and a ceiling plate form (6b), attached to the top of the stand (6a), having a plane shape matching the bottom profile of a product to be formed,
• the holding mechanism (7) having a plurality of support pillars (7a) disposed on the base plate (5), a support plate (7b) having a window hole (70) surrounding the ceiling plate form (6b) and movable in a Z-axis direction on the support pillars (7a), and at least one pair of raising/lowering actuators (7c) fixed to the base plate (5) and having output ends connected to the support plate (7b),
• the sheet restraining mechanism (7d) having a framelike restraining plate (74) for clamping the periphery of a sheet in the thickness direction of the sheet between itself and the support plate (7b) and a restraining actuator (75) for applying a controlled restraining force to the sheet periphery by way of this restraining plate (74),
• the balanced movement mechanism (9) having on the support pillars (7a) and the base plate (5) means for making the support plate (7b) maintain horizontality as it moves;
• ii. a pressing mechanism (8), disposed above the holding mechanism (7), having at a distal end thereof a pressing tool part (80) for making contact with the upper face of the sheet and forming a product shape in cooperation with the ceiling plate form (6b);
• and
• iii. a plurality of numerically controlled drive devices for moving the tool set and the pressing mechanism (8) with respect to each other in X-axis, Y-axis and Z-axis directions, which drive devices move the pressing tool part (80) around the ceiling plate form (6b) on a path of movement matching the product shape and move the pressing mechanism (8) and the support plate (7b) in the thickness direction of the sheet with respect to the ceiling plate form (6b).