Packaging method and apparatus
US3956975A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 1975 |
| Grant date | May 18, 1976 |
| Priority date | — |
| Expiry date | Mar 19, 1995 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/7166
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Apparatus and method for forming sealed joints by welding layers of thermoplastic coated paperboard together. One outer surface of the paperboard layers is placed in engagement with back-up means, and the opposite outer surface of the paperboard layers is engaged by vibrating means so that the thermoplastic coating of the paperboard is heated by the vibration to weld the layers together. The apparatus and method is particularly useful in forming sealed joints for paperboard cartons, such as milk cartons of the type shown, for example, in U.S. Pat. No. 3,309,841. The vibrating means may be an ultrasonic transducer of the type disclosed in U.S. Pat. No. 3,526,792, for example.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.