Abstract: A sabre saw is provided with a generally tubular saw bar journalled for linear movement in a journal bushing secured in the top portion of the housing and rotatable therein with means provided so that they rotate together. The journal bushing is provided with a generally annular collar in turn provided with a plurality of generally radial notches and a cantilever leaf spring is mounted to the housing with its distal end adjacent the collar and shaped for selective engagement within the notches. A slide trigger is slidably carried by the housing at a top portion thereof convenient to the operator's thumb control which when slid towards the saw bar depresses the cantilevered leaf spring against the collar and into a selective one of the notches when they are aligned for locking the saw bar against rotation. Rearward movement of the trigger slide is effective to release the cantilevered leaf spring wherein it will pop up out of the notch and permit free rotation of the saw bar.

Abstract: A single air gap permanent magnet electric motor is provided with field magnets formed as thick annular segments concentric with the axis of rotation of a solid non-magnetic cylindrical armature. The field magnets are magnetized radially to the axis and have oppositely polarized pole faces facing the axis. The ratio of the thickness to the inner diameter of the annular segments is maintained within a defined range to provide for a high magnetic flux density across the single air gap.

Abstract: A display system utilizing incandescent lamps arranged at the intersection points of a matrix array of row and column conductors includes a plurality of load resistors connecting the row conductors to a first voltage source and a plurality of load resistors connecting the column conductors to a second voltage source. To energize a selected lamp, the row conductor connected to that lamp is connected to the second voltage source and the column connected to that lamp is connected to the first voltage source.

Abstract: A lockstitch sewing machine utilizing a needle looper to extend upwardly through a work material to grasp an upper thread and pull it downwardly through the work material to a looptaker which casts the upper thread about a lower thread in order to form a lockstitch. When the needle looper is in an upper position to catch an upper thread, a hook needle is exposed and thread is deflected into the hook thereof. As the needle looper is retracted to a depressed position the hook needle is moved to a guard position so as to retain the upper thread therein during transit. When the needle looper is at its lower position, the hook is again exposed to release its thread to a looptaker for concatenation with a lower thread.

Abstract: A button sewing device is provided with a base; a pair of needles which carry collapsible thread formed loops, and project from the base for use in penetrating a layer of material and the holes of a button to be attached to the material; and with elastomeric material over the base compressible by pressure on the material to which the button is to be attached, and expandable to raise such material and thereby cause the loops to be opened above the button for receiving a thread bundle.

Abstract: A round foot controller has a molded cover 75 attached to a molded base 11 by interengaging projections 79 and 16 extending in opposite directions toward each other from the rims of telescoping walls 77 and 13. The wall 77 is near the perimeter of the cover and is concentric with another wall 76 that surrounds the wall 77. The wall 13 concentrically surrounds another wall 14 in the base. The base has openings 96 and the cover has corresponding openings 97 left by the respective molds that form the undersides of the projections 16 and 79. The double-walled structure of the cover telescoping with the double-walled structure of the base prevents inadvertent access to the electrical components in the foot controller. However, the resistence of a variable resistor 21 or 103 in the controller, can be varied by pressure on any part of the cover 75.

Abstract: A variable voltage, the magnitude of which corresponds to the controlled gain of a circuit through which stitch parameter controlling signals are passed is generated at the wiper arm of a potentiometer connected across a voltage source. The voltage thus obtained from the potentiometer is applied to a decoding circuit that has a plurality of output terminals to supply current to individual semiconductor devices that change their visible condition in response to such current. The decoder causes specific ones of the semiconductor devices to respond in that way so as to produce a pattern directly related to the gain of the circuit through which the stitch information passes. The decoder may be arranged to generate a bar graph representation of the gain or the change may be limited to the semiconductor device that represents the most extreme such device that would be affected by the voltage from the potentiometer for a given setting.

Abstract: A sewing machine supporting work table including a pair of front legs is connected to a chest of drawers by parallel links on which the table is movable between alternate positions in an arc carrying the legs over an underlying surface. In one position of the table, the top of the table is a top for the chest of drawers and the legs blend into the chest, whereas in the other position of the table the top projects frontally therefrom providing space for the knees of an operator and the legs are separated from the chest.

Abstract: A chain stitch conversion throat plate for a lock stitch sewing machine, the throat plate carrying a thread loop retaining pin and a thread stripper device actuated by the up and down motion of the sewing machine feed dog. The thread stripper device includes a block pivotably supporting a wire form having one end for extending beneath the feed dog for up and down motion therewith, and the other end extending adjacent the thread loop retaining pin for stripping the retained loop therefrom on downward motion of the feed dog.

Abstract: A sewing machine hook is provided with a combined needle guard and hook beak which is mounted in the rim of a hook so as to cause the guard to be engaged by a needle when the path of rotation of the hook beak, and the combined needle guard and hook beak to be pivoted into a position preventing the hook beak from engaging the needle.

Abstract: A stitch length and reversing control for a sewing machine is uniquely arranged to facilitate the selection by a machine operator of the length of stitches to be formed in a work piece, to enable the operator at a convenient location on the machine to quickly reverse the direction in which work is fed from a forward feeding direction to a reverse feeding direction, and to enable the operator to sustain the operation of the machine in a reverse feed mode with hands off the control.

Abstract: A positioning pin which permits a sewing machine cabinet to be adapted to accommodate a variety of sewing machines. The positioning pin has a flange dividing the pin into two unequal lengths. The positioning pins are received by bores formed in the base of the sewing machine and the cabinet work surface to properly locate the sewing machine with respect to the work surface. The pins may be reversed end-for-end to adapt to sewing machines having bases with differing heights.

Abstract: A bobbin case for use in machines having underbed thread trimmers incorporates a thread guide consisting of a piano wire soldered to the cylindrical skirt of the case in the region between the leaf tension spring and the point at which the thread is cut by the trimming blade. A groove is formed under and partly through the wire and also partly through the cylindrical skirt. The groove is directed at an angle to the longitudinal direction of the skirt such as to place the groove in line with the direction of movement of the thread to facilitate smooth thread handling.

Abstract: An electromagnetic rotary actuator including three laminated pole pieces equiangularly spaced about an output shaft. Each of the pole pieces has a bobbin coil wound thereabout. The output shaft rotor is magnetized with four 90.degree. poles. One of the stator coils is utilized as a reference coil and is energized with a DC current. The other two coils are each coupled to a respective drive transistor. The drive signals to the two drive transistors are complementary. The resultant magnetic field set up by the three stator coils interacts with the magnetic field from the output shaft rotor to move the output shaft to a selected angular position.

Abstract: A molded, elastomeric strain relief 11 fits into an opening 36 in a housing 43 having an edge 37 and an edge of a wall portion 42 spaced apart by a distance less than the distance between outer edges of shoulders 17 and 18. A central portion 14 of the strain relief substantially fills the opening. An entrance end 13 with a beveled surface 27 on the same side as the shoulder 18 tapers toward the opposite side from which extends a projection 23 with a shoulder 24. The latter shoulder and the shoulder 17 grasp a barrier 56, one wall of which is the wall portion 42, and the shoulder 18 and another shoulder 28 grasp the opposite edge 37 of the opening to hold the strain relief firmly in place. Side recesses 31, 32 include shoulders against which pressure can be directed to deform the elastomeric material enough to get the shoulder 18 into the opening. Once sufficiently in, the strain relief pivots to engage the shoulder 24 behind the barrier 56.

Abstract: A manually actuatable power control device for controlling a power switch in a portable appliance. The power control device is of one-piece construction and has an integrally formed spring member for biasing the control means to a preferred position. The control means is constrained to partake of linear motion for effecting control of the power switch.

Abstract: A sewing machine wherein there is provided a visual representation of the actual amplitude of vibration of certain stitch forming instrumentalities so that the stitch pattern to be sewn or a portion thereof may be visually superimposed upon the work piece by the operator so that the work piece may be properly positioned and the desired amplitude of the pattern selected.

Abstract: A support plate is removably fastened to a sewing machine bed by a retaining device, which device when not in use may be depressed into a position flush with the sewing machine bed. The retaining device has two stable positions for a latch body having a flange on the upper end thereof which may retain a support plate by overlying a slot thereof.