An adjusting unit for producing stored, selectively adjustable working voltages for control and tuning elements, more particularly varactors, comprising variable strip resistances for operation in a voltage divider circuit, said variable resistances being combined into a component, mutually releasable operating elements being mounted on the adjusting unit, said voltage dividers having wiper contacts selectively connectable to a contact rail and being adjustably movable along a track for varying the tapped voltage by means of said elements, said resistances having a common initial and end connecting rails, arranged substantially at right angles to them, and the resistance component representing a ladderlike structure with side rails corresponding to the initial and end rails and the rungs constituting resistances proper, said resistance component being made of a rectangular insulation plate provided with a homogeneous resistance layer for producing a nonlinear resistance curve by stamping out nonrectangular openings so that said resistance strips have different widths along said wiper track.
This application is a division of pending application Ser. No. 491,708, filed Sept. 30, 1965 and now U.S. Pat. No. 3,522,542, issued Aug. 4, 1970. Another division of the aforesaid application is being filed simultaneously herewith.
Priority Data
Dec 21, 1964 [DT] P 14 90 198.5 Jan 29, 1965 [DT] P 15 40 265.0 Jul 02, 1965 [DT] P 15 40 293.4
A self-enclosed variable speed trigger switch adapted for mounting in the handle of a portable electric tool. The speed adjusting mechanism comprises a catch block movable by a stop shaft threaded therethrough with the rear end of the stop shaft abutting a wall in the trigger. Thus, the rear end of this stop shaft is placed in compression to positively take up the trigger return spring force when the lock pin is engaged on the side shoulder of the catch block. This relieves the rotary speed adjusting wheel that is coupled to the front end of the stop shaft of any tensile force and thus enables this wheel to be located in a transverse slot in the trigger so as not to interfere with the finger-engaging surface.
There is provided a combined variable resistor assembly provided with position indicator means for indicating positions of individual variable resistors by respective bright spots adapted to be moved by manipulating the associated variable resistors. This variable resistor assembly may find use mainly for electronic tuners, and with which the present states of the individual variable resistors for volume control, balance control, sound quality control and so forth can be known at a glance at the indicator means.
There is provided a combined variable resistor assembly provided with position indicator means for indicating positions of individual variable resistors by respective bright spots adapted to be moved by manipulating the associated variable resistors. This variable resistor assembly may find use mainly for electronic tuners, and with which the present states of the individual variable resistors for volume control, balance control, sound quality control and so forth can be known at a glance at the indicator means.
There is provided a combined variable resistor assembly provided with position indicator means for indicating positions of individual variable resistors by respective bright spots adapted to be moved by manipulating the associated variable resistors. This variable resistor assembly may find use mainly for electronic tuners, and with which the present states of the individual variable resistors for volume control, balance control, sound quality control and so forth can be known at a glance at the indicator means.
