Abstract: A lock cylinder having a key plug stop comprising an elongated arcuately formed wire received in an annular groove in the key plug. One end portion of the wire stop is retained in a slot in the cylinder shell. Opposite end portions of the stop are disposed in the path of the key and cooperate with the key to limit rotation of the plug relative to the cylinder shell. The stop may be assembled with the plug in either of two positions to selectively limit angular movement of the plug in either a clockwise or counterclockwise direction from a key withdrawal position.

Abstract: A liquid pressure extrusion method and device for extruding a billet into a tube or tubular member wherein combined dies are used for extruding a solid billet therethrough under a liquid pressure.

Abstract: Method and apparatus for forming material by passing it through a container, in which the material receives the force required to form it by contact with driven, recirculating members which make up the inner wall of the container and define the passage available for the material. This passage may be of constant cross-section, or may diverge. The invention includes both the extrusion of solid billet through a die held at the container outlet and the compaction of powder into a coherent solid.

Abstract: A tool for forming substantially rectangular cross sections on conduits. Two mateable collars are disposable about the exterior of a conduit and have forming surfaces which can be pressed against the conduit's wall to predetermined extents to cause the conduit to assume the desired outside rectangular dimensions. Such pressing is provided by two threaded fasteners, each of which extend through one of the collar members and into threaded engagement with the mateable collar. The assembled collar configuration may be disengaged from, rotated about, and reclamped on the exterior of the conduit so as to provide uniform wall formation if the shape of the desired conduit permits such collar rotation. To assure complete contact between the conduit's exterior and the forming surfaces of the collar, two wedge members are axially inserted in the conduit's opening.

Abstract: An apparatus for forming electrical coil bars used in dynamoelectric machines of any size and cone angle. The apparatus includes at least one rotatable frusto-conical shaped member whose major diameter, minor diameter, and cone angle are adjustable to form coils for any sized dynamoelectric machine. By guiding an end portion of an electrical coil bar against the conical surface in a spiral configuration about the conical member's axis of rotation, the electrical coil bars may be caused to lie along a frusto-conical surface when assembled in the dynamoelectric machines. The frusto-conically shaped member has a plurality of radially extendible struts at one axial end thereof, a plurality of radially directed support members at the other axial end thereof, and a plurality of shaping ribs extending between the struts and support members.

Abstract: A bending machine for bending longitudinally elongated channel-shaped sheet metal members according to the present invention consists of a frame and a die set including a female die assembly and a male die assembly and drive means for driving the die set to and fro between an open and closed position. The female die assembly consists of two members, one of which is held stationary relative to the frame and the other of which is movable relative to the first for movement towards and away from the male die element. The first member of the female die assembly serves to clamp the channel-shaped member with respect to the male die element and the second member of the female die assembly serves to form corrugations in the elongated channel-shaped members.

Abstract: A heavy duty truck liner for working on a truck, or large trailer, where a plurality of pulling and pushing operations are required to straighten a frame, etc. A plurality of tracks in the form of a rectangle surrounding the normal position of the truck and body, is prepared and set into the concrete floor of the work room. A large inverted U-frame is set on rollers which are adapted to travel longitudinally along the long sides of the track. The frame is large enough to completely encircle the truck and body can be moved readily along the track so as to be opposite any point on the side walls of the body where pulling or pushing operations are required. A folding platform is attached in a slidable manner to the sidewalls of the frame so as to position the platform at any level on either side of the body. Hydraulic locking means are provided to lock the frame in any selected position so as to withstand any pulling and pushing forces required.

Abstract: Acccessories are disclosed, in their preferred forms, for use in conjunction with an apparatus for repairing and straightening vehicles having a support surface, for supporting vehicles thereon, including an array of regularly shaped apertures which extend vertically therethrough. A unibody clamp is disclosed including adjustable jaws for removably gripping the pinch weld of a unibody frame. Abutment wings are further provided on the clamp for abutting with a stop member which accepts, substantially in line, the counterforce from the clamp. A first connector member is further provided on the clamp for attaching a chain held in an elevated position by an elevated chain apparatus. First connector member further allows the use of a down pull member including a chain directed to the clamp by a rotatably mounted pulley. A second connector member is further provided on the clamp allowing the exertion of a force perpendicular to the pinch weld of the unibody frame.

Abstract: A thermal bridge is employed to compare thermal transfer characteristics of test and reference surfaces immersed in identical fluid environments so as to determine thermal transfer characteristics of the test surface substantially independent of fluid environment. The thermal bridge is balanced, the test surface is caused to be scaled to a greater degree than the reference surface and a comparative measurement is made with the two surfaces exposed to identical fluid environments. The method is performed by a single probe having two or more surfaces that are heated and of which the differential temperatures are monitored. Readings are adjusted to compensate for effects of a varying fluid environment.

Abstract: A detector comprises a pair of electromechanical transducers for disposition on a fluid-filled conduit in an acoustically coupled relationship, an adjustable gain driving amplifier responsive to the electrical output of one transducer for driving the other transducer, an automatic gain control circuit for automatically adjusting the gain of the driving amplifier maintaining the system on the margin of oscillation, and an indicating circuit for detecting modulation of the driving signal. Bubbles passing through the conduit increase the gain required to maintain the system on the margin of oscillation, and are detected as modulations of the driving signal. In a preferred embodiment, this bubble detector is utilized as a refrigerating system test instrument.

Abstract: A testing method and apparatus for use at service stations to establish whether gasoline refueling systems meet government regulations for gasoline vapor emission. The apparatus includes a boot used to surround a gasoline dispensing nozzle while delivering gasoline to an automobile gas tank. The boot is of flexible material and has a hollow wall defining a vapor collection chamber, the inner part of the hollow wall having apertures distributed over its surface to allow gasoline vapor to be drawn into the chamber by suction. The outer part of the hollow wall has a stub connectable to a tube leading to vapor emission analyzing equipment. In the method, such a boot is used to recover the emitted vapors directly from the vehicle-nozzle interface region and the recovered vapors are drawn by a pump through a flow meter and delivered to an analyzer.

Abstract: An oxygen sensor consisting of an oxygen ion conductive solid electrolyte member coated with a porous cermet structure which exhibits a metallic and ceramic skeleton develops a resistance change in response to a change in oxygen partial pressure at elevated temperatures. The resistance change, when coupled to an electrical circuit, provides an electrical indication of the oxygen partial pressure of the atmosphere contacting the oxygen sensor.

Abstract: A transducer bridge circuit arrangement includes at least two bridge circuits connected in parallel to each other. Any interaction affecting the sensitivity of the bridge circuits relative to each other is eliminated. For this purpose the circuit arrangement includes two power input terminals and two measured signal output terminals. In order to avoid a signal component, which represents force couple related load components between the two measured signal output terminals, these terminals are arranged on the one hand between the two strain gauges which measure tension or compression only and, on the other hand, between the two strain gauges which measure tension as well as compression. In such an arrangement the power input terminals and the measured signal output terminals are effectively rotated by 90.degree. relative to prior art transducer circuit arrangements, whereby interaction between the individual bridge circuits in a multiple transducer system is eliminated.

Abstract: A conventional strain gage mechanism is mounted within a support bracket having at least an end wall or plate through which the plunger of the strain gage extends. The dial of the strain gage is so arranged and calibrated as to be representative of 25% R.M.A. compression values responsive to a force applied against the free end of the plunger. The end plate insures that the device is applied consistently against different pieces of compressible material.

Abstract: A multi-axis load cell of the type adapted to generate signals corresponding to each of the various force and moment components exerted on the load cell is disclosed, comprised of a hub and a housing interconnected by three flexure arms, each flexure arm fixed at one end to one of the hub or housing and at the other end to a beam flexure element fixed to the other of the hub or housing. Each flexure beam is designed to be readily deflected in directions aligned with its respective flexure arm but offers substantially greater resistance to deflection in other directions, so that a centering bias force is provided without restricting the bending deflection of the flexure arms relied on to measure the force and moment components.Two sets of displacement transducers are provided, each set consisting of three transducers, with the first set arranged in pinwheel fashion about the load cell axis to measure the XY displacement components and torsional about the load cell axis.

Abstract: A gage for setting sewing machine bobbin tension is comprised of a tensioning member which is located substantially within an open topped cylindrical case and which has gripping means arranged to extend out of the case, through an elongate opening in its side, for releasably engaging thread from a sewing machine bobbin. The tensioning member includes a tightly wound coil which fits rotatably over a post located in the case, but which is prevented from rotating on the post by means of a tab extending from one of its ends. The other end of the coil extends across the case to provide a straight indicating section, and an extention section extends at an acute angle from the indicating section back across and out of the case through the opening. A window located in a lid which covers the open top of the case is arranged to display a portion of the indicating section.

Abstract: The disclosure relates to measurement of the rate of advance of a drill bit from a floating drilling installation. The process includes joining a point of the drilling system, fixed in translation with the movement of the drill string, at the lower extremity of which is a drill bit, to a fixed point solid with the ground, by a cable of constant length passing through a pulley system fixed to the floating drilling installation, to measure the angular displacements of different pulleys of the pulley system and to derive from them magnitudes representing the rate of advance of the drill bit. This procedure, applied to a floating drilling system, eliminates the effect of vertical movements, that is swells or waves, from the measurements.

Abstract: Air under pressure feeds through a pin-to-box casing collar of a surface casing and into the drilling mud space inside. Drilling mud within the casing opposes air pressure in the line. When drilling mud level drops too low, air pressure in an air supply line to the collar falls below a threshold level and an alarm will sound, a chart recorder will record the event and its duration, and warning lights will flash. The chart recorder records the history of the pressure in the air supply line to indicate either an adequate drilling mud level or an inadequate level and plots these facts as a function of time. The air flow rate can quantitatively be determined by a rotometer. The rate at which air flows through the line can be adjusted.

Abstract: An arrangement for electro-magnetically measuring level of and/or distance to molten metal contained in a container, particularly a torpedo ladle wagon. Separate transmitter and receiver coils are located displaced relative to each other at or in the container walls so that the molten metal forms an AC magnetic screen between the coils when reaching a predetermined level. Before the molten metal cuts off the alternating magnetic field from the transmitter coil to the receiver coil, the alternating magnetic field sensed by the receiver coil is increased due to alternating magnetic field generated by electric currents induced at the surface of the raising molten metal. The top amplitude of the signal obtained in the receiver coil increases as the wear and erosion of the container lining proceeds.

Abstract: A strip thermometer of the liquid-crystal type for clinical use is disclosed, in which the melting point of the liquid crystals in the several display points of the strip is the temperature of an easily accessible area of the patient's body, the scale of the digital values being shifted so as to indicate the temperature of another area of the patient's body which corresponds to the temperature which is read out in the part of the body wherein the temperature readings are actually taken.

Abstract: A temperature indicating probe comprises a liquid-in-glass thermometer encased in a clear plastic housing having a magnifying lens portion facing the thermometer tube to facilitate quick and acurate reading. The housing includes a series of tapered, cylindrical shaped portions separated by a step or shoulder, which are respectively insertable into variously sized standard medical appliance line openings or fittings, for sensing and indicating the temperature of the working fluids being carried through the line.

Abstract: Toxic gases from oil and gas wells are sampled by a gas sensing assembly arranged at a distance from a wellhead being monitored. A gas pickup device arranged adjacent the wellhead is connected to the gas sensing assembly by a feed line through which gas is drawn from the pickup device to the gas sensing assembly by a suction pump system.

Abstract: An electrically heated mold for making test specimens of concrete. The mold has two substantially identical mold halves pivotally mounted to each other and electric heating units selectively operated in response to the temperature variations in the concrete of the main structure. Each mold half has a heat transferring wall member which has a mold surface and an outer surface against which one of the heating units is placed. The mold is insulated and has a number of additional features designed to facilitate manufacture and operation of the mold as well as to increase its working life.

Abstract: A low "g" hydrostatic accelerometer including a differential pressure traucer interposed between a sensing mass, and a pressurized low density fluid.

Abstract: The device comprises an elongated acoustic wave translating isotropic body and a pair of transducers applied over one of the two parallel end faces thereof. Said transducers are arranged with relatively crossed axes of linear transversal polarization. The other end face of the isotrope body is intended to be applied to a sample or a structure made of an acoustically active substance presenting anisotropy, either intrinsic or induced, with respect to acoustical polarization. The length of the isotropic body is such that when the transducers are both simultaneously driven by pulsed high frequency voltages which are modulated in respective phase quadrature by a low frequency oscillation, the two transversal acoustic waves propagated through the body vectorially combine so that the opposite end face of the body is the subject of a constant amplitude acoustic wave which rotates at the speed of the pulsation of the low frequency.

Abstract: An ultrasonic transducing unit comprising a central section, which cooperates with only a small portion of the relatively large aperture of an acoustic lens, and an annular section, which cooperates with the remainder of the aperture, can be selectively operated by switch means to utilize the relatively large depth of focus detected signal of the central section alone or to utilize the relatively small depth of focus detected signal of both the central and annular sections together.

Abstract: An electrodynamic sound converter which comprises a magnet adapted to generate a magnetic field and direct same onto the surface of the workpiece to be checked by the electrodynamic sound converter, and which also includes an excitation coil located between the magnet and the workpiece to be checked for generating electromagnetic oscillations. That end of the magnet core of the magnet which faces the workpiece to be checked is so designed that the magnet core decreases in cross section toward its foremost point which is closest to the surface of the workpiece to be checked, the rate of increase increasing in the direction toward the foremost point of the magnet core.

Abstract: A balanced crankshaft mechanism for the two piston Stirling engine which permits the use of a single crankpin and eliminates side forces on the pistons. A triangular yoke has connected to its respective apexes the connecting rods for each piston and the crankpin. One end of a rocking lever is connected to said yoke at a point between the points at which the connecting rods are attached. The other end of said rocking lever is connected to the base of the machine. As the crankpin rotates, the separate connecting rods and their respective pistons are moved with a phase relation appropriate for a two piston Stirling engine, and side forces are absorbed by the rocking lever, rather than by the pistons. A simple means of balancing the reciprocating inertial forces is described, which is also applicable to other types of Stirling engines.

Abstract: A system for continuously monitoring both compressive and tension loads on a force carrying member. The system includes a transducer having a pair of physically aligned piezoelectric elements which each are adapted to sense changes in stresses in the load carrying member to produce electrical output signals which can be separately utilized by tension and compression load monitoring circuits. The illustrated system discloses a compression load monitoring circuit that is responsive to electrical output signals generated by one of the piezoelectric elements upon an increase in compressive stresses in the member and a tension load indicating circuit which is responsive to electrical signals generated by the other piezoelectric element upon an increase in tension stresses in the transducer.

Abstract: A gear and boss protector for the spring driving mechanism of a tap selector such as a voltage regulator. A pair of hook cams form the protective means and they are mounted rotatably on the crank driven by the spring driving gear. One of the hook cams engages the driving boss on the driving gear should the gear reverse rotation in one direction, while the other hook cam engages the driving boss on the driving gear should the gear reverse rotation in the opposite direction. The engagement of the driving boss by the hook cam prevents the crank from being suddenly released causing damage to the gear or boss.

Abstract: A speed change device comprises a stack of discs alternating with friction rings, the rings being disposed in a drum with which they are rotatable, the discs being rotatable with an input shaft extending into the drum. The stack is gripped between an abutment connected to the drum and a bell-shaped member fixed to an output shaft extending into the drum. The gripping is ensured by clamping means comprising elements having complementary conjugate surfaces and resilient means disposed between one of said elements and an axial abutment movable with the drum or bell-shaped member. The elements of the clamping means comprise a screw rotatable with the output shaft but axially movable therealong and a nut co-operating with the screw, the nut being rotatable with the drum but axially movable therealong.

Abstract: A belt-drive speed reducer, particularly for driving an airplane propeller from a standard automobile engine, features a protective housing attached to the motor, being supported by suitable borings 22 and 40 of the shaft of a drive pulley 10, on the one hand, turned by the motor crankshaft and, on the other hand, the propeller shaft supporting a driven pulley turned by a belt which, in section, exhibits V-shaped ribs. The bearing of the propeller shaft has on its periphery a disk eccentric with respect to the propeller shaft, the rotation of which disk in the boring of the housing regulates the tension of the belt.

Abstract: A screw-nut screw transmission coupling with ball circulation of the type comprising a first elongated element and a second tubular element substantially coaxial to each other and with an external and an internal helical track respectively, is described. Said two tracks are disposed facing each other to define a helical rolling path for a plurality of balls disposed in mutual contact along said path and along a recirculation duct connecting the two ends of said path together, and said first element is constituted by an inner core and a metal strip wound in a cylindrical helix about and along said core, said strip being rigid with said core and having a cross-section which is concave outwards to define one of said helical tracks.

Abstract: A hand control arrangement for a hydrostatic transmission having a single manually actuated control to vary the driving direction and speed of the transmission and wherein the movement of the hand control lever is limited to a predetermined path making it possible for the operator to sense various speed levels of the transmission.

Abstract: A link drive mechanism for vertically moving the slide of a mechanical press comprises a power driven eccentric unit carried by a horizontal shaft arranged substantially vertically above the connecting means for the slide and having first and second adjacent eccentrics, a first eccentric strap carried by the first eccentric and extending downwardly therefrom and having first and second laterally arranged pivot connections, a first link pivotally connected between the first pivot connection and the connecting means for the slide, a second eccentric strap carried by the second eccentric and extending laterally therefrom, a substantially vertically extending fulcrum lever arranged laterally from the horizontal shaft and pivoted intermediate its ends and having one of its arms pivotally connected to the second eccentric strap, and a second link pivotally connected to the other arm of the fulcrum lever and to the second pivot connection of the first eccentric strap.

Abstract: A device for operating a parking brake including a pivotable lever for stretching a brake cable and a one-way locking mechanism for the lever having a pawl and ratchet teeth. The pawl is actuated by the balance of a spring force and the reaction force of the cable stretched so that the pawl is driven into engagement with the ratchet teeth by the reaction of the cable against the spring force when the cable is stretched beyond a predetermined tensioned condition.

Abstract: A power distributing apparatus for vehicles includes an input shaft, first and second output shafts, a simple planetary gear set having a carrier operatively connected to the input shaft, a ring gear cooperating with the first output shaft, and a sun gear selectively engaged with the second output shaft, and means for selectively engaging the carrier and the sun gear and for integrally rotating the sun gear and the carrier in the engaging state of the sun gear and the carrier, and for more slowly rotating the sun gear than the carrier in the disengaging state of the sun gear and the carrier.

Abstract: The operational speed of a fluid drive unit in a hydromechanical transmission is limited by means of an overspeed preventing, one-way clutch establishing a positive drive connection between torque transmitting elements of the hydromechanical transmission. Two power paths are established between the planetary gear unit and the input shaft of the transmission to drive an output shaft at a variable drive ratio controlled by a variable displacement type of fluid drive unit. One of the power paths is established through fixed ratio gearing while the other power path is established through the fluid drive units while operating within a speed ratio range limited by the one-way clutch.

Abstract: An apparatus for the straightening (dressing or peening) of relatively large circular-sawblade blanks, especially for hot-sawing circular saw blanks, comprises a stand for a forging hammer which is provided with a pneumatic peening hammer directed upon a working point and a support which is linearly shiftable relative to the hammer. The hammer is vertically reciprocatable and the translation direction of the support is horizontal and perpendicular to the axis of the hammer. The support comprises linearly-shiftable carriage provided with a table which can be rotated about a vertical axis through at least 180.degree. and the peening portion of the hammer is also rotatable about a vertical axis through at least 90.degree..

Abstract: A bolt extractor for extracting broken bolt or tap shanks from threaded bores. A length of welding rod is fixedly seated within a bore in a headed stud to project from opposite ends of the stud. The stud shank, which is of a diameter less than that of the tapped bore, is encased with electrical insulating material. The end of the welding rod projecting from the shank is welded to the bolt or tap which is to be extracted by conventional welding equipment connected to the welding rod of the extractor. The broken bolt or tap is then extracted from its bore by applying a wrench to the head of the stud.

Abstract: A chain wrench has a handle having a chain element pivoted to the handle by a pair of links to permit passage of the free end of the chain between the links, whereby the chain may be wrapped in full circumscribing relation to a workpiece. The handle has a camming surface and teeth elements positioned to confront the exposed surface of the chain when it is wrapped around the workpiece. The chain has a cleated surface on one side and has a smooth surface on the opposite side. In one mode of operation, the cleated surface confronts the workpiece to engage the same, whereby the cam surface causes the cleats to grip the workpiece and anchor the chain at that point when said handle is actuated to apply torque to the workpiece, the smooth surface permitting the chain to slide over said camming surface prior to applying torquing action upon said handle to afford snug engagement of the chain about substantially the entire circumference of the workpiece.

Abstract: A tool for cutting tubular or solid cylindrical workpieces such as rigid polyvinyl chloride or like rigid resin pipes, soft metal pipes, etc. transversely thereof comprises a main body having a bearing portion including a pair of freely rotatable members, a vertically movable cutter arm pivoted to the main body and provided with a pair of rotary cutters opposed to the rotatable members in corresponding relation thereto, a cutter arm lifting assembly for moving the rotary cutters toward or away from the rotatable members, and an intermittent feeder mounted on the cutter arm for rotating the rotary cutters in the same direction. The workpiece is placed on the bearing portion of the main body and set in position substantially at right angles to the rotary cutters. After the edge of one of the rotary cutters has been brought into contact with the workpiece, the cutter arm lifting assembly is operated to hold the workpiece between the bearing portion and the rotary cutter.

Abstract: The invention relates to an assembly of members for programming and controlling the process of a blanking or die cutting machine, which process, because of simply comprising shearing machine blows, is programmed and controlled by merely fixing before hand the amount of blows that the machine should give, and then controlling the given blows. The invention is characterized in that the assembly or unit comprises a filing cabinet intended to accomodate the blanks or die cuts to be used for the process, each file being provided with members responsive to the presence of said blanks or die cuts, so that as a blank or die cut is withdrawn or picked up, the relative programming members are activated as set on the control board.

Abstract: An input shaft is drivingly connected to a crankshaft of a punch press for rotation at a preselected speed. A geared cam drive drivingly connects the input shaft to a driven feed roll so that continuous rotation of the input shaft is converted to intermittent rotation of the feed roll. The intermittent rotation of the feed roll is timed with the punching operation so that the feed roll intermittently advances a preselected length of stock material to the punch press after each punching operation. Bevel gears drivingly connect the input shaft to a pull roll that rotates to continuously unreel stock material from a coil. During the punching operation, rotation of the feed roll is interrupted forming a loop in the stock material between the pull roll and the feed roll.

Abstract: An apparatus for a power hand saw. A guide spans the work to be cut, and the saw is positively attached thereto, the saw blade being adjacent the guide. An adjustable support extends to one side of the work, includes one member disposed against an edge of the work and pivotally attached to the guide, and includes a second member pivotally attached to the one member and slidably attached to the guide. The guide is unitary, having a turned-under section connected to the adjustable support.

Abstract: An electronic musical instrument of a waveshape memory type comprising: a plurality of waveshape memories for storing waveshapes of different tone color, and means for variably mixing the outputs of the plurality of waveshape memories for generating tone signals of varying tone color. The mixing ratio of the different waveshapes may be varied with the lapse of time or according to the touch of the key operation or to the tone pitch.

Abstract: A key assignor comprising a scanning means, a first clock memory, a second memory for releasing a switch information, a comparator, a priority circuit device, a means for inhibiting the write-in operation, and a means for extracting key codes. Key switches are divided into blocks to scan the latter without scanning all of key switches. Scanning time can considerably be reduced as compared to prior arts, thereby enhancing response greatly.

Abstract: A key code generator for electronic musical instruments which has a switch matrix circuit having a plurality of switches disposed at the intersections of two sets of buses, means for simultaneously applying signals to the switch matrix circuit from one of the two sets of buses to derive outputs from a plurality of blocks into which the buses of the other set are divided line by line, a memory for detecting the blocks that even one switch is in the on state from the bus outputs of the switch matrix circuit and temporarily storing signals of the detected blocks, a first priority selector for selecting block signals in a predetermined order of priority from the bus outputs and sequentially outputting the block signals with a predetermined clock pulse, means for inhibiting the block detecting operation during outputting from the first priority selector and applying the selected block signals to the buses of the detected blocks to sequentially scan only the detected blocks, a second priority selector for selecting

Abstract: An automatic musical instrument in which a chord discrimination and a musical performance circuit are arranged so that a comparator with multiple input terminals on one side, is connected to a memory circuit having multiple basic types of chords memorized. The comparator has multiple input terminals on the other side connected to key switches through a shift register. The comparator, furthermore, has a control electrode connected to a clock pulse generator which is connected, in turn, to multiple input terminals of the memory circuit, by way of two counter circuits. The latter have multiple output terminals connected, respectively, to two latch circuits. The comparator has an output terminal connected to control electrodes of the latch circuits. The musical performance circuit has a decoder connected to multiple output terminals of one of the latch circuits.

Abstract: Disclosed are guitars having quick attach, quick release string securing mechanisms for use with string sets of measured lengths. A first embodiment of strings has loops formed on both ends, while a second embodiment of strings has a loop formed on one end and an anchor ball secured on the other. Each guitar disclosed has tuning mechanism including transversely extending string holding posts over which the string loops may be hooked. Guitars utilizing the first string embodiment have crosspiece structure carrying upwardly projecting posts around which the loops of the other strings ends can be hooked. The guitar utilizing the second string embodiment has crosspiece structure defining slotted rearwardly opening sockets for receiving the anchor balls secured on the other string ends. The string holding ends of each of the string holding posts are preferably formed as ball-shaped members and may be formed by screwing a ball on a treaded shaft.