| 摘要 |
497,553. Making envelopes. GRAY, R. L. Sept. 27, 1937, No. 14753/38. Convention date, Feb. 17, 1937. Divided out of 490,268. Drawings to Specification. [Class 94 (ii)] A machine for making window envelopes &c. comprising an assembling device for covering a window opening in a blank with a transparent patch by means of a uniting film of thermoplastic adhesive, and a heating and pressing device for effecting the sealing together of the patch and blank, is characterized in that, for securing reliable assembly in speedy mass production, the action of the assembling pressure is prolonged, e.g. by the provision of resilient means in the drive of the pressing device which yields considerably during each normal working stroke, so to provide an adhesive - activating dwell during continued rapid motion of the machine. The machine described is as shown in Specification 490,268. Specifications 409,274 and 409,307 also are referred to. |
