| 摘要 |
A grinding tool includes a rotary motor driving a rotary drive shaft, a first grinding disc having a centre opening for receiving the drive shaft, with the outer end of the drive shaft projecting through the opening in the grinding disk, a spacer assembly having a socket at one end receiving the projecting end of the drive shaft, a pin at the opposite end, and a spacer between said socket and pin, a second grinding disc having a centre opening for receiving the pin of the spacer assembly with the outer end of the pin projecting through the latter opening and an outer collar attached to the projecting end of the pin for securing the two grinding discs to the drive shaft in spaced-apart relationship such as to enable the grinding tool to simultaneously cut two spaced grooves. |
