| 摘要 |
In a molding apparatus employing opposed endless belt conveyors to mold a non-rigid material into a rigid material, the problem of one conveyor being driven at a slightly greater speed than the other conveyor to produce harmful shear stresses within the molded product is avoided by driving both conveyors at generally the same speed during start-up until the rigid product extending between the two conveyors will tend to drive the slower conveyor at the speed of the faster conveyor, at which point the drive for the slower conveyor will be disconnected. One-way clutches may be placed in the drive of both conveyors so that it does not matter which conveyor is slower, or a one-way clutch may be placed in the drive of only one conveyor and the other conveyor constructed so that it will inherently tend to run faster than the one conveyor, or a selectively releasable coupling, such as a clutch, may be placed in the drive of one conveyor so that the drive of the one conveyor may be disconnected. Preferably, a synchronous motor is used to drive each of the conveyors from a common power source, so that the synchronous motor associated with the slower conveyor may be deenergized when the slower conveyor drive is uncoupled.
|
