| 摘要 |
PROBLEM TO BE SOLVED: To stably secure a predetermined molding pressure by constituting a fluid spring unit out of a cylinder, a piston arranged in the cylinder, and compressible fluid filled between the cylinder and the piston. SOLUTION: A fluid spring unit 60 for specifying a molding pressure is detachably contained in a vertical hole 49 of a case 50. The unit 60 has a cylinder 62, a piston 64 arranged in the cylinder 60 and compressible fluid filled between the cylinder 62 and the piston 64. A hollow male threaded member 14 is detachably engaged with a female threaded part 70 of a lower end of a vertical hole 49c. The 74 is engaged at a predetermined amount with the part 70, a cylindrical member 12 is pressed down at a predetermined amount in an axial direction, and the fluid in the unit 60 is compressed by a predetermined amount, thereby setting an initial load. Thus, a predetermined molding pressure is stably assured, its lifetime is prolonged, a shim regulating operation and a belleville spring replacing operation are eliminated, and hence its production efficiency can be improved. |
