| 摘要 |
The frame saw comprises attachment units for a saw blade (1) which passes in a vertical plane between two turning-points with the aid of a crank mechanism (6,7,8,9). Rollers, arranged in pairs (11,12,13,14), feed logs through the sawing frame, powered by a hydraulic motor (15) attached to a pump (18) and a tank (19). - A valve (23) is placed on a pipe (16) connecting the pump (18) to the motor (15) in order to cut communication between the connecting pipe and the tank during at least the major part of the blade's downward movement, thus forcing hydraulic fluid from the pump to the motor to drive the rollers. The same valve opens the flow between the pipe and the tank when the blade is at its lower turning-point, thus momentarily shutting off the motor and the rollers.(1) |
