Method for making flat bottom plastic bag
    1.
    发明授权
    Method for making flat bottom plastic bag 失效
    平底塑料袋的制作方法

    公开(公告)号:US5102384A

    公开(公告)日:1992-04-07

    申请号:US401773

    申请日:1989-09-01

    IPC分类号: B31B37/00

    摘要: A method is disclosed of constructing a flat bottom in a plastic film tube having an open upper end, a closed lower end formed by a transverse seal, forward and rearward sides and a pair of opposing pleated sides that interconnect the forward and rearward sides. The method includes the steps of releasably engaging a lower vacuum and a lower clamp with a transverse section of the rearward side of the tube to provisionally hold the transverse section. A lateral section of the forward side is gripped and raised by an upper vacuum and an upper clamp to expose a portion of the pleated sides such that first and second pockets are formed, respectively, in the sides. The sealed lower end is drawn toward the upper end to fold the tube along first and second transverse fold lines in the forward side, along a third transverse fold line in the transverse section of the rearward side, and along fourth and fifth fold lines, respectively, in the pleated sides such that the first and second pockets are located in the pleated sides, respectively between the first and third fold lines and the lower end of the bag. Pressure is applied to the tube to form creases along the first, third, fourth and fifth fold lines, which define the perimeter of the flat bottom of the tube.

    摘要翻译: 公开了一种在塑料薄膜管中构造平底部的方法,其具有敞开的上端,由横向密封件形成的封闭下端,前侧和后侧以及一对相互折叠的折叠侧面,其相互连接前侧和后侧。 该方法包括以下步骤:将下部真空和下部夹具与管子后侧的横截面可释放地接合以临时保持横向部分。 前侧的横向部分由上部真空和上部夹具夹持并升高,以暴露一部分打褶的侧面,使得分别在侧面形成第一和第二凹部。 密封的下端被拉向上端,以沿着第一和第二横向折叠线沿着前侧的横向部分中的第三横向折线以及沿第四和第五折线分别沿着第一和第二横向折叠线折叠 在褶皱侧,使得第一和第二袋分别位于打褶的侧面,分别在第一和第三折叠线和袋的下端之间。 压力被施加到管,以形成沿着第一,第三,第四和第五折线的褶皱,其限定管的平底部的周边。