A duplex pipette comprises a housing, a pair of cylinders separately formed in the housing to extend substantially in parallel to each other, first and second piston members each having a lower end portion slidably received in one of the cylinders and a handle portion projecting outside the cylinder, and a pair of pipette tips mounted on the lower end of the housing by way of a connecting member, each of the pipette tips having a passage which communicates one of the cylinders with the outside o...

An electrooptical scanner includes an optical system having mirrors for directing light from one side of a document through a lens to a charge coupled device and from the other side of the document through the same lens to a different charge coupled device. The scanner scans both sides at the same time using a straight paper path.

A method for manufacturing double ply packaging bags includes feeding a first packaging web, the first packaging web including a window patch that is cut out or pre-cut, feeding a second packaging web, the second packaging web including another window patch that is cut out or pre-cut, applying a fastener assembly to a fed-through packaging web, perpendicular to a window patch, attaching the fastener assembly to the packaging web, attaching the two packaging webs to each other to form a double pl...

An operator sets a distance from the page head of an alignment mark using a mark position setting switch mounted in a duplex printing system. A first printer forms the alignment mark in a position of the distance from the page head of a web, and reports position information about the alignment mark to a second printer. The alignment mark is detected by mark detection means of the second printer. Control means performs control of a web transport speed so that a phase between generation timing of ...

An automatic document feeder includes first, second, third, and fourth paths for guiding movement of a document. The document is fed through the first path and a scanning module so as to allow for scanning of a first side surface of the document. Thereafter, a switching gate is pivoted to a first position so as to allow the document to be moved from a front section of the second path onto a roller unit via the fourth path and a rear section of the third path. The rotational direction of the midd...

A pair of mandrels providing a crossover system for use in a dual string of well tubing in which each of the mandrels are adapted to be connected in one of the well tubings and each of the mandrels includes an open bore therethrough and a pocket for receiving flow control devices in which the mandrels are connected together with a fluid conduit extending between the pockets. The mandrels are connected together with the open bores being positioned side by side and the pockets positioned side by s...

A duplex radiocommunication transceiver with carrier frequencies that are made available to all parties of a network comprises a generator providing a plurality of pairs of frequencies and which is equipped with a stepping switch, a coder for coding the address of a correspondent, means for transmitting an occupation frequency in a channel which is occupied, means for decoding an address code being received, means for interpreting the presence of the occupation frequency, and means for stopping ...

Method and apparatus are herein disclosed for creating a duplex copy. First and second dry toner images are formulated on an image retaining member. The first image is electrically transferred to a storage member. A sheet of final support material is placed over the first image supported on the storage member and the second image electrically transferred to the opposite side of the support sheet. Sufficient pressure is applied to the sheet while it is in contact with the storage member to bond t...

A tuning system for a radio receiver is disclosed in which manual tuning is performed by means of mechanically slug-tuned coils and automatic, signal-seeking tuning is performed by all-electronic means including a varactor. The coil and varactor form a resonant circuit which can be tuned over the entire frequency range of interest by variation of one tuning element, the other being held at a constant reactance value. For manual tuning, the varactor is held at a constant reactance value while the...

The duplex strainer structure comprises two parallel elongate strainer housings flanking rotatable valving means in a common plane, the valving means being operative to place in service alternatively either of the two fluid strainers while the other undergoes cleaning. The valving members, their operating stems, and the strainer axes are arranged in coplanar relationship, to provide a compact substantially flat assembly in which the strainer housings protectively flank the valving means.