| 摘要 |
A door closer assembly and method of making the assembly, in which the closing force is exerted by at least one closing spring. The door closer assembly comprises a housing, a rotor journalled in said housing to deliver torque, and at least one piston apparatus, wherein said housing, said rotor, and said at least one piston apparatus are comprised of the same material of construction and exhibit at least substantially the same thermal expansion coefficient. |
