| 摘要 |
A polytunnel arrangement with a cover 16 supported upon hoop members 14, the cover partly secured to a rotatable bar 20, the bar rotating to wind cover material onto or from the bar 20, during such rotation the bar 20 translating/moving about a barrel roof tunnel profile 18 defined by the hoop members 14. The bar 20 is coupled to a drive shaft 24 by either a universal or flexible coupling 22. A support arrangement supports the drive shaft such that an end part of the shaft 24 remote from the bar 20 follows an arcuate path substantially matching the tunnel profile 18 during de-skinning. The drive shaft may be provided with means to secure it to a drive input, and the input may comprise an electric motor, a chain drive, or a hand crank. The support arrangement may be releasable, and may comprise one or more releasable clips. |
