Abstract: A workbench comprises a work surface (2, 4) disposed on a supporting structure (3). The work surface comprises a vice jaw member (4) carrying a first vice jaw and a worktable (2) having a second complimentary vice jaw (51a). The worktable, in a working position thereof, lies in the same plane as the jaw member, and the jaws face one another and are adapted to be moved towards and away from one another by vice operating means (9). The worktable is pivotally mounted with respect to the supporting structure about an axis lying adjacent the back edge (51b) of the worktable, thereby enabling the worktable to be pivoted away from the supporting structure to give access to the underside of the worktable.

Abstract: An abrasive sheet such as sandpaper has standard dimensions to fit 1/3, 1/2 or 1/4 sheet sanding machines having dust extraction facilities. The sheet has perforated delineated separable or frangible areas adapted to be removed by the user to form one pattern of an array of patterns of holes in the sheet to correspond with the holes in the sole plate of the particular model of abrading or sanding machine which the user is employing. This enables one sheet to be used with several different models. Such an arrangement also ensures that the unperforated portions of the sole plate of the abrading machine are covered by unseparated frangible areas of the abrasive sheet. This is accomplished by defining the frangible areas using circular configurations of perforations.

Abstract: An assembly for mounting a heat-generating semiconductor to an associated heat sink whereby direct heat conducting contact is assured between the semiconductor body and the heat sink by an element which electrically isolates and insulates the semiconductor from the other components while at the same time locating and providing pressure to clamp the semiconductor on the heat sink. The present assembly provides good thermal contact and adapts to thermal expansion of the system during operation to assure the maintainance of the contact regardless of temperature changes within the device. The assembly comprises a heat-dissipating base element having plan dimensions which are larger than the plan dimensions of the semiconductor. A retainer member is formed of a dielectric material and has means for locating and retaining the semiconductor. The retainer member also includes a plurality of arms connected to the locating and retaining means.

Abstract: A photoelectric perforation sensor for accurately detecting a perforation in a moving web. The sensor comprises two large photodiodes in a bi-cell configuration. The photodiodes lie in the direction of web travel. As the perforation begins to pass between an LED source and the bi-cell, light from the LED illuminates one photodiode but not the other. As the perforation becomes centered over the photodiodes, both photodiodes receive equal amounts of illumination and a signal is generated indicating location of the perforation.

Abstract: A multiple sheet detecting apparatus is disclosed which includes an ultrasonic transducer responsive to a time varying electrical signal to produce a time varying ultrasonic signal which impinges upon sheet(s) at a position along a predetermined path. A second ultrasonic transducer receives a portion of the ultrasonic wave which passes through such impinged upon sheet(s) for producing a second time varying signal. Comparison means are then provided which compare the phase relationship between the time varying electrical signals and produce an indication when such phase relationship indicates a multiple sheet feed condition has occurred.