摘要:
A detector for continuously monitoring the integrity of a coating on a piece of material. The detector includes an upper bar and a lower bar held near the surfaces of the material. Each bar carries multiple conductive probes in contact with the corresponding surface and electrically connected to an electronic detection circuit. Adjacent probes are connected to electric terminals having different voltage potentials. When probes from the same bar carrying different voltages short together, such as by contacting the surface of conductive sheet material, the detection circuit signals an insufficiently coated area has been found. The short between probes must be large enough to cause a short for more than a predetermined time. The upper probe bar is rotatable to prevent damage to the upper probes by a bent edge on a sheet of material.
摘要:
A method and apparatus for forming a bag provides a tube of material that is passed over a former. A portion of the tube is folded over the former to define the rim of the bag. Portions of the rim are then welded. The apparatus includes arms that move transverse to the tube. The arms carry crimping fingers that pivot to fold the tube up and in over the former.
摘要:
A former allows rectangular tubes of material to be quickly formed for creating bags having rectangular cross sections. The former provides a transition between a round former and a rectangular former so that the material used to form the bag is initially wrapped into a tube around a round former so that the material does not tear on the corners of the former. The round tube of material is then drawn down over the former of the invention to change the round tube to a rectangular tube that may be formed into the bag.