| 摘要 |
FIELD: construction. ^ SUBSTANCE: frame block comprises folding frame and external box. Between external side and internal side of frame unit there is a ventilation channel, in which air flow limitation device is installed with surface limiter that rotates relative to bearing element fixed on frame. The limiter is installed with the possibility of displacement between open and closed positions. Limiter is in open position, while air flow speed in ventilation channel is below limit value. Channel element of air flow limitation device adjoins upper closing wall of upper folding frame at mounted frame unit and forms internal finished section of ventilation channel. Such channel element is simple in assembly. ^ EFFECT: invention will make it possible to simplify assembly of air flow limitation device. ^ 17 cl, 5 dwg |
