| 摘要 |
<p>1292002 Cutting webs UNITED STATES GYPSUM CO 17 Dec 1969 [23 Dec 1968] 61552/69 Heading B4B Apparatus for severing a plastics web 10 adhered to spaced boards 12, comprises a carriage 24 provided with a catch 70 for contacting the edge of a board 12 so that the carriage is moved with the board allowing blades 56 mounted on the carriage to penetrate the web and move apart to sever the web between the boards. The carriage comprises a rail 50 on which the blades 56 are slidably mounted and a rail 52 on which the catch 70 is resiliently mounted, both rails having rollers 50R, 52R, respectively, which engage camming tracks 26u, 26l, 36u, 36l, on both sides of the carriage. Boards 12, e.g. gypsum wallboards, have adhesive applied, and a web 10 of vinyl plastics rolled on to their upper surfaces. The covered boards 12 are moved by an endless conveyer 14 over plates 13 between which is mounted the catch 70 which is biased by a spring (65), Fig. 3 (not shown), into engagement with the leading edge of a board 12. At this point, the rollers 50R and 52R are positioned as shown in Fig. 6 and on movement of the carriage with the board 12, the roller 50R moves down a ramp 28 causing the blades 56 to penetrate the web. The blades 56 are moved apart by a cam track 68 engaging rollers 60 connected to the blades. On completion of the transverse cut, the roller 50R moves up a ramp 30 opening a normally closed gate 34 to lift the blades 56 from the material and the roller 52R drops through a gap 37 on to the track 361 to lower the catch 70 and allow the carriage to return to its initial position under the action of a spring 74. The blades are moved towards each other during the return stroke, either by a spring 61, or by an additional set of rollers 60 engaging the insides of the tracks 68, Fig. 3a (not shown).</p> |
