Abstract: A tool has a machine body, a driving assembly, and a machining assembly. The driving assembly has a first holding base, a second holding base, a threaded rod, a moving base, and a thermal compensation gap. The threaded rod is formed as a single part and has a driving thread segment, a first assembling segment, and a second assembling segment. The driving thread segment has a first end and a second end opposite the first end. The thermal compensation gap is formed between the first end of the driving thread segment and the first holding base. The machining assembly is mounted securely on the moving base.

Abstract: A brake mechanism has a brake disk, multiple clutches, and multiple brake assemblies. The brake disk is coaxially connected to a rotatable work table. The multiple clutches are capable of clamping the brake disk. The multiple brake assemblies correspond in position to the multiple clutches. Each one of the multiple brake assemblies has a housing, an abutting shaft inserted in the housing, and multiple elastic units received in the housing and abutting against the abutting shaft. The multiple abutting shafts of the multiple brake assemblies abut against the brake disk for stopping the work table from rotating. A hydraulic system applies hydraulic pressure inside the multiple housings of the multiple brake assemblies and forces the multiple abutting shafts to depart from the corresponding clutch, making the work table rotate again.

Abstract: A brake mechanism has a brake disk, multiple clutches, and multiple brake assemblies. The brake disk is coaxially connected to a rotatable work table. The multiple clutches are capable of clamping the brake disk. The multiple brake assemblies correspond in position to the multiple clutches. Each one of the multiple brake assemblies has a housing, an abutting shaft inserted in the housing, and multiple elastic units received in the housing and abutting against the abutting shaft. The multiple abutting shafts of the multiple brake assemblies abut against the brake disk for stopping the work table from rotating. A hydraulic system applies hydraulic pressure inside the multiple housings of the multiple brake assemblies and forces the multiple abutting shafts to depart from the corresponding clutch, making the work table rotate again.