Power assisted rotatable film wrapping apparatus
US4524568A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 1982 |
| Grant date | Jun 25, 1985 |
| Priority date | — |
| Expiry date | Aug 27, 2002 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB65B2210/18
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A rotatable film wrapping apparatus for wrapping a load on a conveyor with an overwrap of stretched plastic film web, having a film web pre-stretching mechanism which is provided with a constant torque by a power assistance mechanism. The power assistance mechanism comprises a stationary ring adjacent a rotary ring on which the film roll and pre-stretch mechanism are mounted, and a friction roller on the rotary ring which contacts the stationary ring to transfer rotational energy to the pre-stretch device as the rotary ring rotates. The pre-stretch mechanism comprises a downstream roller across which the film is drawn to the load at a speed which varies, and an upstream roller linked by gears to the downstream roller so that the upstream roller rotates at a fixed fraction of the speed of the downstream roller to stretch film between the rollers. The energy of the friction roller is transferred through an adjustable constant torque device to the pre-stretch mechanism without controlling the speed of the pre-stretch mechanism, and since a constant torque is added to the pre-stretch mechanism, the force on the film to the load can be substantially reduced while allowing the pre-stretc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.