Abstract: A balance arm for flat weighing machines has a rigid frame formed by girder-section rails extending between side beams. A pair of knife-edges are attached to each rail to extend parallel to the longitudinal axis thereof with the sharp edges of each pair of knife-edges in alignment. The rails are secured to the side beams such that all the sharp edges lie in a common plane. The configuration of the rails enables all the knife-edges to be precision ground on a common grinding machine after attachment to the inside of the rails and before the side beams are attached to the rails.

Abstract: In a weighing machine a flexure bar is attached as a cantilever to a beam. The force to be measured is applied to the cantilever end of the flexure bar by a weighing lever. In order to protect the flexure bar against overloading the beam is mounted to be pivotable and is held by a spring force acting counter to the direction of action of the force to be measured against a first fixed stop. The spring force is chosen such that said beam moves out of contact with the first stop when an overload is applied to the weighing lever. In addition, a second fixed stop is provided to restrict the pivotal movement of the weighing lever and thus prevent the transmission of further force into the flexure bar.

Abstract: Apparatus is provided for introducing a force to be measured from a force transfer element into the free end of a bending rod held rigidly at one end. The apparatus comprises means, e.g. two knife-edges for guiding the force transfer element in the direction of the bending rod, a first rounded contact surface on the force transfer element, a second rounded contact surface on the bending rod, a coupling element having first and second flat parallel spaced substantially horizontal surfaces and interposed between the first and second contact points with its first surface bearing against the first contact surface and its second surface bearing against the second contact surface, and means for holding the coupling element substantially centrally and resiliently relative to the first and second contact surfaces.

Abstract: There is disclosed an electrically price-calculating balance, in particular a balance for a shop's counter, comprising an indicator part and a weighing part each constructed as a separate unit. The indicator part has an upper surface which is constructed as a support surface for the weighing part and the weighing part is mountable on the indicator part.

Abstract: A bending force receiver has a bending rod which is supported in a main bearing and has a force introduction location. Strain gauges are mounted on the bending rod in a region between the main bearing and restraining means limiting axial movement of the bending rod due to an applied force. This region is enclosed by a casing. The bending rod projects from the casing at the main bearing in the form of an elastically bendable cantilever arm including the force introduction location. The free end of the cantilever arm co-operates with an overload abutment.

Abstract: A surveillance system for preventing shoplifting comprises marking elements made of material of high magnetic permeability attached to the goods in a store, and magnetic field generating coils generating a magnetic field in the exit areas from the store. Two different alternating magnetic fields are produced on opposite sides so that the configuration of the field within the exit area is continuously changing. Introduction of a marking element into this area causes different frequencies to be produced which are sensed by a sensing element which then emits a signal. The marking elements can be deactivated during a normal purchase by magnetically saturating the material.

Abstract: An error preventing incremental measuring system utilizes a plurality of scanning elements associated to a relatively movable divided scale. But, instead of merely comparing the results of a plurality of independent channels originating at the scanning elements and terminating at separate counters, the system according to the invention combines the signals from the scanning elements by way of a logical network into a further signal similar resp. dissimilar to one or more of the scanning signals, thus avoiding the necessity of fault tolerances.

Abstract: A band saw which has a displaceable guard rail that covers the saw blade in the cutting region thereof above the feed table and is adapted to be displaced upward in a direction parallel to the saw blade and away from the feed table to the height necessary to allow passage of the stock that is being cut. The band saw includes apparatus for raising the guard rail the necessary height in response to exerting pressure by the stock against the guard rail in the direction of cutting, and the apparatus will then maintain the guard rail at a height conforming to the contour of the stock as the latter is passed through the saw blade. Other apparatus provides smooth movement of the guard rail during cutting operations and provides for securing of the guard rail when the band saw is not in operation.