Abstract: A metallic housing encloses a suspended substrate circuit and is arranged so that the waveguide input/output port within the housing has double-ridge transitions to the suspended substrate circuit.

Abstract: A planar millimeter wave circuit for splitting a very wide input frequency and into three or more lesser bands utilizes bandpass filters exclusively. A triplexer is made by connecting the bandpass filters with coupled line equivalents fed by a conductor with a characteristic impedance the same as the input conductor to the filters and of an appropriate length so as to make the diplexer appear open or nearly open circuited over the adjacent frequency range of a third bandpass filter used in the triplexer or, alternatively, over the adjacent frequency range of a second diplexer connected so as to form a quadruplexer.

Abstract: The disclosure concerns a drive device for a double thread chain-stitch buttonhole sewing machine. The machine has a first drive shaft for driving the sewing needle and for moving the cloth support plate for sewing. It has a separate worm shaft for moving the cloth support plate to the sewing position and also for operating a knife for cutting the buttonhole. A first respective electromagnetic clutch operates the sewing needle drive shaft, and a second respective electromagnetic clutch operates an intermediate shaft which then operates the worm shaft for operating the cloth support plate and knife operating shaft are provided. A drive shaft is connected with the armature part of the first electromagnetic clutch on the sewing needle driving shaft. That armature part is gear connected with an armature part of the second clutch on the intermediate shaft.

Abstract: A photoelectric device on the head of a sewing machine detects the trailing edge of a fabric workpiece and initiates a count of pulses representing increments of the steps of displacement of the workpiece in stitch formations. Each step is subdivided into a plurality of segments which are represented by respective multiplicities of increments so that from a count of increments after detection of the reference point to a particular angular orientation of the arm shaft, a stitch combination can be drawn from a memory which will include stitches of an original length and stitches of a length reduced from the original by a fixed amount so that in the number of stitches of the selected combination the row will be completed to a certain distance from the reference edge.

Abstract: An attachment for a sewing machine comprises a looper bar positionable for horizontal oscillation underneath a vertically reciprocating needle, at a level determined by a workpiece feeler engaging the upper surface of a fabric being sewn, which is swingably carried on the stem of a presser foot resting on the workpiece while the latter is intermittently advanced by a bottom feeder periodically rising from a slot in a stitch plate and a reciprocable gripper foot synchronized therewith to act as a top feeder. A first sensor detects a rise in the presser foot, to an extent indicating the presence of resilient padding between an upper and a lower fabric layer, to activate the looper bar; a second sensor temporarily deactivates the first sensor whenever the bottom feeder projects above the stitch plate.

Abstract: A device for feeding to a sewing machine a strip of fabric, in particular a longitudinally folded band to serve as a pocket welt, comprises a generally oval-shaped guide mountable on the sewing-machine base and provided with sides shaped as U-profiles and with a tongue at an output end for folding a fabric strip upon passage thereof along a feed path to a sewing station at the machine. A beam of light from a gallium-arsenide source traverses the feed path in the region of the tongue to energize a photocell upon passage of a workpiece, the photocell being connected to a stitch counter for activating the same upon energization by the source. The guide has a length scale with graduations spaced in the direction of the feed path for implementing the manual positioning of a fabric strip prior to the feeding thereof to the sewing station, while the stitch counter is operationally coupled to the reciprocating sewing-needle drive to arrest the same upon counting a predetermined number of stitches.