Coextrusion of multilayer articles using protective boundary layers and
apparatus therefor
    2.
    发明授权
    Coextrusion of multilayer articles using protective boundary layers and apparatus therefor 失效
    使用保护性边界层的多层制品的共挤出及其设备

    公开(公告)号:US5269995A

    公开(公告)日:1993-12-14

    申请号:US955788

    申请日:1992-10-02

    摘要: A process and apparatus for the coextrusion of a multilayer polymeric body is provided which incorporates protective boundary layers into the body, protecting the layers from instability and breakup during layer formation and multiplication. The process includes the steps of providing at least first and second streams of heat plastified extrudable thermoplastic material which are combined to form a composite stream having the first substreams and second substreams interdigitated. A third stream of heat plastified thermoplastic material is supplied to the exterior surfaces of the composite stream to form protective boundary layers adjacent the walls of the coextrusion apparatus through which the heat plastified polymer streams pass. Layer instability and breakup are avoided using process conditions which would otherwise adversely affect the optical and/or mechanical properties of the articles which are formed.

    摘要翻译: 提供了一种用于共挤出多层聚合物体的方法和装置,其将保护性边界层结合到体内,从而在层形成和增殖过程中保护层免于不稳定和破裂。 该方法包括提供至少第一和第二热量塑化可挤出热塑性材料流的步骤,其被组合以形成具有交叉指向的第一子流和第二子流的复合流。 将热塑性热塑性材料的第三流提供给复合材料流的外表面,以形成邻近共挤出设备的壁的保护边界层,热塑化聚合物流通过该壁。 使用过程条件来避免层不稳定性和破裂,否则会对形成的制品的光学和/或机械性能产生不利影响。

    High efficiency gear pump for pumping highly viscous fluids
    7.
    发明授权
    High efficiency gear pump for pumping highly viscous fluids 有权
    高效齿轮泵用于泵送高粘度流体

    公开(公告)号:US06210139B1

    公开(公告)日:2001-04-03

    申请号:US09398181

    申请日:1999-09-17

    IPC分类号: F04C216

    CPC分类号: F04C13/002 F04C2/086

    摘要: A gear pump exhibiting improved efficiency over a broader range of fluid viscosity and pump speed includes a compression zone defined between each of a pair of pump gears and internal walls of a gear chamber, wherein the compression zones have a non-uniform thickness along a longitudinal direction of the gears. The geometry of the compression zones provides a mechanism whereby the drag of the viscous fluid which is induced by the rotation of the pump gears carries the viscous fluid through a progressively narrower gap in the direction of rotation ending in a final smooth pinch-off at the start of the seal zone. The geometry of the compression zone maximizes the drag and pressurization of the viscous fluid being pumped into the teeth of the gears, thereby assisting in the complete filling of the teeth. The result is improved fill efficiency over a broader range of pump speeds and over a broader range of fluid viscosity.

    摘要翻译: 在更宽的流体粘度和泵速范围内显示出提高的效率的齿轮泵包括在一对泵齿轮和齿轮室的内壁之间限定的压缩区域,其中压缩区沿纵向具有不均匀的厚度 齿轮方向。 压缩区的几何形状提供了一种机构,由此由泵齿轮的旋转引起的粘性流体的阻力将粘性流体沿着旋转方向上的逐渐变窄的间隙运送,从而以最终平滑夹紧 开始密封区。 压缩区域的几何形状使得被泵送到齿轮齿中的粘性流体的阻力和加压最大化,从而有助于完全填充牙齿。 结果是在更宽的泵速范围内和在更宽的流体粘度范围内提高了填充效率。