FIELD: logging. SUBSTANCE: prior to deflecting properly positioned stops 28 and 36 by full-length logs, the stops are initially held in the preset positions only under the gravity forces and are used as freely movable nonload-bearing indicating flags of the stops. As soon as the stops begin to deflect piston, cavities are separated from return line. The moving full-length logs are subjected to progressively increasing counteracting force developed by stops 28 and 36, which at this stage serve as partially load-bearing stops. Simultaneously with beginning of deflection of the stops multi-gear drive is shifted in intermediate reverse gear, thereby intensifying retardation process. Under the effect of the multi-gear feed drive the logs return backwards for a short time, the stops become pressed against the forward faces of the full-length logs and follow their movement. The command is then given to the multi-gear drive for moving the logs at a low speed forward and for operation of the stops as load-bearing ones. Measurement with stops is performed for logs with close tolerances. After engagement of the full-length logs with freely standing stops 28 and 36 serving as signalling flags, for the remaining logs the measurement commences in response to commands of pickups 40 and 50 of the distance covered by timber materials as a function of time. This measurement may also be performed by means of pickup and pulses counter in response to commands of which the lengths of the logs are measured with the stops disengaged. EFFECT: extended operating capabilities. 17 cl, 15 dwg
