| 摘要 |
PURPOSE:To easily form a multilayer printed board having neither interlaminar shifting nor interlaminar bubble by a method wherein each interval between hot plates is measured at four corners and cylinders for controlling the parallelism between hot plates to control the parallelism between hot plates to allowable parallelism by calculating on the basis of measured values are provided. CONSTITUTION:Displacement detectors 20, which detect the intervals between an upper hot plate 4b and a lower hot plate 5b opposing to each other at four positions, and cylinders 22 for controlling the parallelism between the hot plates, which are provided near the respective detection positions so as to apply reaction to decelerate the speed for decreasing the thickness of a board, are provided. Each valve V connected to each cylinder 22 controls the pressure of oil to feed to the cylinder 22 so as to make the reaction nearly zero in 'OFF' state while controls the flow rate and pressure of return oil so as to bring the speed for decreasing the interval between the hot plates and reaction to the predetermined values in 'ON' state. The detected values of the intervals between the hot plates with the displacement detectors 20, are inputted to an operator 21, which calculates the parallelism between the hot plates opposing to each other on the basis of the detected values and issues an 'ON' signal to the valve gear V so as to conform with the pre-set allowable parallelism. |
