SHIPPING TUBE PVC INTERLOCKING END PLUG
Original Publication Date: 1994-Jun-01
Included in the Prior Art Database: 2002-Mar-04
Extruded PVC tubes or rails are often used for shipping discrete electronic products. These tubes are usually custom designed for the size and shape of the device to be shipped; but are occasionally designed to accommodate more than one device geometry The extrusion process and PVC material combined with device geometry can limit the tube's rigidity allowing the walls to flex which limits the effectiveness of conventional stopping or plugging devices used to keep the product in the tube. One common stopping device is the pin or nail, as shown in Figure 1, which is inserted through holes in the tube and lock into place by an enlarged area located on the shah of the pin. A common plugging device is the end plug made of semi-firm rubbery material shaped to slide into the end of the tube and form a friction fit. Both of these devices work very well for most applications. However, when using the PVC tube system for shipping relatively heavy devices where the design of the tube allows excessive flexing the effectiveness of these devices can be marginal and even unacceptable. An end view of such a tube is shown in Figure 2. When compressive forces are applied to the tube in the direction shown by the arrows pointing in, the tube will flex as indicated by the arrows pointing out. This flexing can cause nails and plugs to release.