Abstract: A semifinished part feed unit having an indexing table for transferring a stack of semifinished parts from a loading station to a pickoff station; a robot handling fixture for transferring one part at a time from the pickoff station to a press; a detecting device for detecting the characteristics and the position assumed by the stack in the pickoff station; and a control and processing system for generating control signals for the handling fixture in response to input signals from the detecting device.

Abstract: A scaled, isolated range test chamber is provided for testing motion sensors, such as ultrasonic occupancy detectors, in which the detector to be tested is mounted on a drawer and slid into an enclosed chamber. The enclosed chamber includes multiple motion simulators, such as rods rotated by stepper motors, which are controlled by computer to provide an accurate and repeatable scaled test environment. The ultrasonic radiation is concentrated by the scaled test environment to avoid testing anomalies resulting from time and temperature changes or human error factors. A master sensor is calibrated to detect the predetermined minor motion of the movement of a human hand in an arc through a discrete distance of one foot in one second. The motion simulators are adjusted to rotate through a larger arc at a closer distance to be detected by the master sensor in order to determine the equivalent simulated minor motion.

Abstract: A small volume prover is disclosed which is compact and capable of obtaining highly reliable measurement, keeping a highly accurate base volume without being affected by temperature and pressure of fluid to be measured.The prover includes a cylindrical outer housing having a fluid inlet and a fluid outlet spaced apart from each other, a cylindrical measuring conduit having both open ends and first and second sets of fluid ports radially made in a wall thereof and coaxially mounted within the outer housing and an annular wall mounted between the outer housing and the measuring conduit at the position between the measuring conduit open end and the first set of ports thereof to form an upstream annular passage and a downstream annular passage. During proving preparation a piston is restrained by a piston actuator provided in the outlet-side end of the outer housing to permit the fluid to pass through the annular passage.

Abstract: An apparatus and method of speedily measuring the strength of individual abrasive grains such as diamonds in which the grains are crushed between two hard rollers and the compressive force exerted on the grain by the rollers at the moment of fracture is measured.

Abstract: A hydrocarbon analyzer for rapidly measuring both methane and nonmethane hydrocarbons is provided. The analyzer includes a nonmethane hydrocarbon absorbing first column connected in series with a methane absorbing second column. A sample gas is propelled in a carrier gas through a carrier gas line into the first and second columns via a change-over valve for switching between a branched line severably connected between the carrier gas line and a first flame ionization detector for measuring nonmethane hydrocarbons and a second flame ionization detector connected to the second column for measuring methane.

Abstract: The present invention provides an acoustic cell for determining the composition of gas mixtures. The acoustic gas composition analysis cell has transducers acoustically isolated from the cell body through the use of an acoustic isolation material positioned at least between the transducers and the transducer housings to produce a signal-to-noise ratio of at least 4 to 1. Additionally, the transducers employed in the acoustic cell operate in the kilohertz range, reducing attenuation in the gas mixture being analyzed. The cell body employs vacuum seals which permit the use of the cell in line with vacuum equipment.

Abstract: Apparatus and method for detecting leaks in pressure-regulated gas systems are provided, particularly LPG gas systems. The apparatus allows detection of movement of the diaphragm in a regulator. The method provides for measuring the leakage rate and confirming that the regulator is operating under proper conditions for the test.

Abstract: A method of testing for leaks in a closed fluid filled system and a system tested by such method are provided, the method comprising the steps of disposing the system in a chamber, disposing a fluid in the chamber under a pressure so that if a leak path of a certain size or larger exists in the system such fluid of the chamber will be forced through the leak path to change the fluid condition in the closed volume of the system, removing the system from the chamber after a certain period of time, then subjecting the system to a certain pressure and temperature condition so that an expandable part of the system will be in an adverse expanded position beyond its normal position for that certain pressure and temperature if the leak path of at least a certain size existed, and then detecting the adverse expanded position of the part of the system.

Abstract: A bubble detecting apparatus for an infusion pump, including a set of ultrasonic sensor constituted by an ultrasonic oscillator and a receiver provided, respectively, at opposed locations on an outer face of a liquid transport tube for feeding liquid such as medicinal liquid by a predetermined pumping operation of a pumping mechanism such that air bubbles produced in or mixed into the liquid in the liquid transport tube are detected by the ultrasonic oscillator and the receiver. In the apparatus, at least three sets of the ultrasonic sensors are arranged along the liquid transport tube at different intervals.

Abstract: Refrigerant type is identified and determined by storing in electronic memory indicia representative of saturation pressure/temperature characteristics of a plurality of differing refrigerant types. A liquid refrigerant sample of unknown type is obtained and vaporized under controlled conditions of temperature and pressure. Refrigerant vapor temperature is measured at two different vapor pressures during the vaporization process, and such temperatures and pressures are then compared with the indicia prestored in memory. Two temperature readings at differing vapor pressures are sufficient to distinguish refrigerant type based upon the prestored saturation/temperature indicia.

Abstract: The present invention intends to allow evaluation of the performances of of the function of the ABS, the function of the LSD, and the function of the TRC to be effected easily by using a performance inspection apparatus with prescribed constitution wherein, in addition to a pair of receptive support rollers for receiving a wheel of a vehicle and for supporting the weight of the vehicle directly, a rotation detecting roller which is rotatably driven by said wheel and/or inertially rotatably driven and is separated from the weight of the vehicle is provided, and data required for evaluation of the operational state and the performance of the ABC function, the LSD function, and the TRC function can be detected respectively by mutually changing and sectioning the arrangements including the rotation detecting rollers.

Abstract: A misfire detection apparatus and method is provided for detecting misfire in cylinders of an internal combustion engine in a motor vehicle. The method includes sensing ionization current through spark plugs in either a distributorless ignition system or a distributor ignition system. The method also includes disabling ionization current sensing during ignition coil discharge time. The method further includes making and storing the combustion ionization measurements in order to determine if a misfire has occurred and if catalyst damage has occurred due to the misfire.

Abstract: Vibration sensors are used to monitor the resonant frequency of each cylinder of a multi-cylinder engine and the detection of an abnormal resonant frequency, i.e., one outside of an established range, is used as an indication that one or more specific cylinders is operating at an improper power level. Vibration signals associated with combustion in each cylinder can be used to perform FFT (Fast Fourier Transformation) with the combustion resonant frequencies for all engine cycles being determined and an averaged resonant frequency for each cylinder obtained. Shifts in the averaged resonant frequency or the detection of a zero resonant frequency for only one of the cylinders can be used as an indication that the cylinder with the shifted or zero resonant frequency is experiencing a low power condition, including misfiring.

Abstract: A diagnostic method is provided for sensing whether an oxygen sensor is still suitable for use in measuring the fuel-air mixture in the exhaust gases of an internal combustion engine. The method involves turning off a heater of an oxygen sensor when the engine is turned off and allowing the sensor to cool. While the sensor cools, the sensor resistance is measured by means of a large pull-up resistor and a small pull-up resistor, with the small resistor being switched into the circuit at regular intervals for a short period of time. The use of the small pull-up resistor not only increases the reliability of the measurements, but also aids in quickly determining when the sensor resistance has increased above a threshold value indicating the sensor is cool. When the sensor is sufficiently cool, the heater is turned on and the sensor is monitored for a decrease in resistance, indicating that the heater is functioning properly.

Abstract: A method for manual inspection of gears. A simple, manual method and apparatus is provided for inspection of a variety of gears. The method is particularly useful for determination of helical angle deviation and taper in helical gears. The gear to be inspected is placed in a suitable holder, or on a smooth support surface. A selected master gear segment, manufactured to precise tolerances such that it would perfectly fit an inspected gear that has no error, is brought into stationary, meshing engagement with the inspected gear. The selected master gear segment is supported in a working position by a support structure in a manner that the selected master gear segment may be displaced about an axis with respect to a reference datum plane. Displacement of the selected master gear is by way of rotation of the gear about a pivot A two axis movement type unit which is used for measuring both helical angle deviation and taper.

Abstract: The average volumetric velocity U.sub.m of a fluid flowing within a large industrial flue stack is determined by a combination of measurement and calculation techniques. The temperature, velocity head and static pressure of the stack fluid are measured at two points within the bounded path of the flue stack. The flight time of a random acoustic noise wave is measured in both the upstream and downstream directions. The path average velocity U.sub.p is determined from the measured values of the upstream and downstream flight times. The fluid velocity is determined using the measured values of the flight times, the fluid temperature, velocity head and static fluid pressure. The determined values of the path average velocity U.sub.p and the fluid velocities are used to determine the average volumetric velocity U.sub.m. A curve fitting algorithm is employed to determine an approximation of the actual fluid flow distribution across the bounded path, and this approximation is used to calculate U.sub.m.

Abstract: A thermal type of flow rate sensor includes heat-generating and temperature-compensating resistors R.sub.H and R.sub.C which are located within a fluid passage to measure the flow rate of the fluid. The linear term coefficient, .alpha., of the temperature coefficient of resistance of R.sub.C is made smaller than that of R.sub.H, whereby any temperature-compensating electric circuit and circuit control can all be dispensed with and the flow rate of a fluid can be precisely detected over a wide temperature range.

Abstract: A flow sensor for sensing heat transfer with a high-speed response, which is manufactured by applying IC micro-machining technology, and which attains an improved heat transfer efficiency by controlling the flow's direction between a heating portion and a sensing portion or by utilizing the intrinsic characteristics of the gas flow. The flow sensor has a substrate whereon a heating portion and a sensing portion are formed each in the form of a bridge supported at both ends or at one end in the direction of the flowing gas to be measured, and which is placed, its surface with the elements down, at the upper inside wall of a pipe for gas to be measured. Its output signal is taken out through lead wires.

Abstract: A gauge for measuring a pre-determined volume of liquid flowing through a conduit. A slug having substantially neutral buoyancy is positioned within the conduit and moves along the conduit at substantially the same rate as the liquid flowing therein. The slug is free to move within a constraint system defining a length of the conduit. The gauge further comprises detection means capable of detecting when the slug has moved a predetermined distance within the conduit.

Abstract: A finger pressure gauge capable of checking finger pressure conveniently and scientifically includes an inner case having a guide pin and a rack, an outer case receiving the inner case and having a pinion corresponding to the rack, wherein the inner case and outer case are retained by an elastic spring provided between them, and a dial covered with a window to show the finger pressure with a hand connected to the pinion, by which a patient can check on his recovery rate during curing by Chinese medicine.

Abstract: An integrated rate and acceleration sensor includes at least one accelerometer formed from a substantially planar silicon body. The at least one micro-silicon accelerometer (MSA) includes a first frame and a proof mass suspended from the first frame by first flexures. The at least one accelerometer has an associated sensitive axis and an associated rate axis that is orthogonally disposed to the sensitive axis. The integrated sensor further includes structure for dithering or vibrating the proof mass along a dither axis that is disposed perpendicularly to both the rate and the sensitive axes. The dithering structure includes at least first and second interdigitated electrodes. Finger portions of the electrodes are disposed for exerting an electrostatic force upon a portion of the planar body in response to an oscillatory drive signal.

Abstract: A capacitance type accelerometer, having a fist silicon plate formed a movable electrode which is moved according to acceleration, two second silicon plates which are disposed on both sides of the first silicon plate with a certain separation distance, and thermal oxide films which are respectively disposed between the first silicon plate except the movable electrode and the two second silicon plates and stick the first silicon plate except the movable electrode and the two second silicon plates together.

Abstract: Presented is a method and apparatus for inspection through use of a variable angle ultrasonic transducer of metallic members such as pipes, conduits, plates and other formed metallic members normally having a surface regularity adhering to a predetermined standard of normalcy. Inspection proceeds in such a manner that irregularities in the surface of the member under test that lie outside the standard of normalcy are sensed, the degree of irregularity determined and converted into an electrical signal that is applied to continually variably control the angular relationship of the ultrasonic transducer with the surface of the metallic member being inspected whereby abnormalities within the metallic member may be reliably and accurately detected, displayed and recorded.

Abstract: A pressure measurement system includes a diaphragm and a chamber for exposing one side of the diaphragm to a fluid. A force transducer is provided for measuring force exerted by the fluid on the one side of the diaphragm independent of diaphragm position. A ferromagnetic plate is attached to the diaphragm to enable removable coupling of the diaphragm with a magnet permanently attached to the force transducer.

Abstract: A rock bolt load sensor assembly for use to determine the load on a nut screwed onto a bolt embedded in a rock face, the assembly comprising a plurality of spring washers arranged to be mounted on the bolt between the nut and a roof plate, and a sensor comprising an induction coil adapted to be, in use, placed around the washers, the sensor including an indicator coupled to the induction coil whereby in use, the spring washers define an air space which varies in dependence on the load on the bolt and the induction coil provides an electrical indication of variation of the air space and the indicator provides an indication of variation of the load on the bolt.

Abstract: The impeller and drum of a motorless in-line mass flowmeter are constructed with small optical targets having high reflectivity. Light is pulsed toward the path of rotation of the targets through optical fibers. The pulse width is small in comparison to the delay between pulses. Reflections of the pulses from the optical targets are conveyed by a single output fiber to a remote location where the optical pulses are converted to electrical pulses. The electrical pulses can be analyzed to determine the speed of the impeller and the deflection angle of the impeller relative to the drum, for accurate determination of the mass flow rate of liquid passing through the flowmeter.

Abstract: A mass flowmeter comprises a nonvibrating conduit providing a flow passage divided into two parallel and equal subpassages by a planar member with the leading and trailing edges secured to the wall of the flow passage, wherein the planar member is torsionally vibrated about the central axis thereof substantially coinciding with the center line of the flow passage, and a pair of vibration sensors detecting the torsional vibration of the planar member respectively at two different cross sections of the flow passage, wherein the mass flow rate of media moving through the flow passage is determined as a function of a phase angle difference between two alternating electrical signals respectively provided by the pair of vibration sensors.

Abstract: Apparatus is provided in which flow to be monitored actuates a device to move past a sensing electrode, causing changes of a capacitive sensing impedance in series with an impedance transformation device. The sensing electrode is at the high-impedance level of the impedance transformation device. Only a small fraction of the stray capacitance of circuit wiring, etc., which is connected at the low-impedance level of the impedance transformation device is reflected as a dulling shunt across the sensing capacitance.

Abstract: On the upper surface of a flexible substrate, four displacement electrodes are arranged. A fixed substrate is arranged thereabove, and fixed electrodes opposite to the displacement electrodes are respectively arranged on the fixed substrate. These displacement electrodes and the fixed electrodes form capacitance elements C1 to C4, respectively. A columnar working body is fixed on the lower surface of the flexible substrate. A bending is produced in the flexible substrate on the basis of an acceleration exerted thereon. As a result, capacitance values of the respective capacitance elements C1 to C4 vary. The capacitance values of the capacitance elements C1 to C4 are converted to respective voltage values V1 to V4. A component in the X-axis direction is obtained as Vx=(V1+V4)-(V2+V3), a component in the Y-axis direction is obtained as Vy=(V1+V2)-(V3+V4), and a component in the Z-axis direction is obtained as Vz=V1+V2+V+V4.

Abstract: A sampling machine for moving a sampling scoop through bidirectional full rotations which are effective to remove multiple sample volumes from a moving conveyor. The sampling scoop has a home position which is maintained by the its drive without requiring a separate brake. A programmable control provides a full range of multiple sampling cycles at high sampling rates. The sampling scoop cavities are comprised of three straight flat surfaces including a pusher surface which is substantially vertical as the sample volume is pushed off an edge of the moving conveyor.

Abstract: A load monitor responsive to tension or pressure is disclosed. The monitor has attachment portions at its ends and a transmitter. The attachment portions are electrically isolated from one another and the transmitter has its output connected to the attachment portions. Cables connected to the attachment portions act as an antenna for propagating the signal to a remotely located receiver.

Abstract: An apparatus is disclosed for measuring the diffusion of hydrogen atoms from a second surface to a first surface of a ferrous metal body as a means of measuring the magnitude of corrosion occurring at the second surface. The apparatus comprises a chamber-defining member which can be sealed to the first surface of the body so as to define with the first surface a sealed chamber. The chamber-defining member is constructed of material sufficiently flexible that upon evacuation of the sealed chamber the chamber-defining member deflects toward the first surface to reduce the chamber volume. The apparatus provides a connecting means for attaching an evacuating pump which is used to evacuate substantially all of the contents of the chamber.

Abstract: A relatively inexpensive coupling for preventing the transmission of thread drunkenness to a carriage or other element being driven by a lead screw. The coupling is formed with an input plate and an output plate both connected to an intermediate member. The connections via flexure members permit movement of the intermediate member relative to the coupling and the output plate to provide uniform motion to a carriage along the lead screw axis.

Abstract: A machine element support comprised of a plurality of axially extensible and contractible servostruts which are individually adjustable and collectively controllable. The struts comprise an outer tubular member and a slidably, interfitted, elongated, inner member. The powered servostruts are movably connected to an machine element such as a spindle head by one of the members on one end and to a rigid machine tool frame by the other of the members on the other end. Linear position sensors mounted on the servostruts serve to precisely measure strut extension and retraction for feedback control purposes. A preferred servostrut configuration is a hexapodal array, in which two servostruts are mounted side by side in each of the three well-known orthogonal axes of machine tool practice, providing six-axis movement and positioning of the tool head or workstation relative to the workpiece.

Abstract: A transmission for providing continuously variable speed and torque comprises a housing, an input shaft, a system of variable throw eccentrics, control means for changing eccentric throw of the variable throw eccentrics, connecting links for receiving eccentric throw from the system of variable throw eccentrics and transmitting it as reciprocal motion and removing ripple from the output, one-way clutches for receiving reciprocal motion from connecting links and transmitting it as rotational motion, and an output shaft. The control means comprise a control shaft rotatably disposed around the input shaft so that both shafts have the same rotational axis and with a fork fixed to the control shaft, a pin fixed at one end to an eccentric and engaged between the prongs of the fork, and means for rotating the control shaft with respect to the input shaft, thus changing the eccentric throw and the transmission ratio.

Abstract: A manual transmission shifted by synchronizer clutches, in which the transmission gears situated between an input shaft and an output shaft are arranged such that, for the shifting of all forward gears, two clutches respectively are closed. A synchronizer clutch participates in the shifting of all forward gears. By bringing the sliding sleeve of the synchronizer clutch into its neutral zero position, a shifting directly into idling can take place from any shifted gear.

Abstract: An auto correction device for wearing end play in worm gear set has a correction worm gear, two linking gears and auxiliary linking gears to help power transmission in a smooth manner. The correction worm gear further includes a threaded thrust block, an auxiliary linking gear, a thrust plate, an expansion spring and a base plate. The thrust of the expansion spring against the thrust plate enables the displacement of the auxiliary linking gear and threaded thrust block to thrust against the correction worm gear to impose a force upon transmission gear to enable the transmission gear to lean tightly against the worm gear. Thus, wearing end play between the worm gear and the correction worm gear is eliminated.

Abstract: A device for improving the ease of operation of an adjustable steering column is disclosed. This device includes a support structure provided with two movable lock flanges between which the column is arranged, and a tie (20) extending between the flanges, one end of which is associated with a stop member (24) for the tie, an intermediate bearing member (25) in contact with one flange and, arranged between the two members, an intermediate bearing washer (51) free to rotate and move axially around the tie, a rolling-contact bearing (52) between the facing surfaces of this washer and of one of the members, at least one rolling member (53) between the facing surfaces of this washer and of the other of the members, and a cage (54) for displacing this rolling member along an incline (28) provided on one of the corresponding surfaces.

Abstract: An actuating mechanism for a multispeed cycle hub comprises a housing adapted to be attached to an end of a hub shaft. A first cam, a second cam, and a pinion having engaging teeth are received in the housing for conjoint rotation. An elongated rack element is mounted for movement along an axis in the housing and is adapted to be coupled to a speed-selection device by a force-transmission member and includes a row of teeth in driving engagement with the engaging teeth of the pinion. A first pivot lever is pivotally mounted in the housing in constant contact with the first cam so as to follow a pivoting motion defined by the shape of the first cam and engages one of two speedchange elements, which are coupled to the transmission in the hub, so as to move the first speed change element upon pivotal movement in response to rotation of the first cam.

Abstract: A brake lever includes two separate sections which are connected to one another by an engaging screw to form an angle between two connected ends of the two sections.

Abstract: A heavy duty hydrostatic transmission having an input into a combined separable pump/motor driven through a shaft in the transmission housing and a "U" shaped double back space conserving gear reduction drive to the axle differential.

Abstract: A new and improved power-driven wrench apparatus includes a housing assembly which includes a gear box portion, a pair of flexible shaft retention portions that extend outwardly from the gear box portion, respective bearing supports located on the flexible shaft retention portions, and a wrench head bearing assembly supported by the bearing supports of the housing assembly. The first gear assembly receives power from a power source. A pair of flexible-shaft gear assemblies is provided wherein each assembly includes a respective driven gear which meshes with the first gear assembly. A respective flexible shaft is connected to the respective driven gear, and a respective worm gear is connected to the respective flexible shaft. The respective driven gears are housed in the gear box portion of the housing assembly, and the pair of flexible-shaft gear assemblies and the respective worm gears are housed in the flexible shaft retention portions of the housing assembly.

Abstract: A ratchet wrench imparts rotational movement to a relatively large workpiece such as the stem of a water main valve or a fire hydrant. The wrench includes an annular driver member, a housing having an elongated recess, a pawl element and a bias element. The annular driver member is adapted to detachably engage the workpiece and includes a plurality of driver teeth disposed circumferentially around its outer periphery. The housing receives the annular driver member so that rotational movement can be imparted to it within the housing and the handle structure extends from the housing to provide mechanical advantage for imparting the rotational movement. The elongated recess extends into the housing along a longitudinal access. The elongated recess is positioned with respect to an imaginary line tangent to a selected radius of the annular driver member such that the longitudinal axis is disposed substantially parallel to or coextensive with the selected radius.

Abstract: A tool handle having a tool head mounted at a first end of the tool handle includes a handle shaft telescopingly mounted within the tool handle arranged for securement within the associated handle tube in a first position and projecting the handle tube in a second position to provide for increased application of leverage and torque in use of the tool head.

Abstract: In a tool arrangement, an end part of a holder shaft is provided with a seat which provides a stable support for a cutter insert in at least two of the principal directions utilized in a machining operation. Stresses imposed on the cutter insert during the machining operation are transferred in an effective fashion to the shaft. The arrangement includes at least one tightenable fastening device which, after tightening, engages with the cutter insert and forces it against at least one surface of the seat. The cutter insert has stop parts with which the fastening device is intended to engage only after the cutter insert, through displacement relative to the seat on the shaft and whilst the cutter insert still in contact with the seat, has reached its operating position.

Abstract: A device for trimming wallpaper, including champs for fastening the device to a flat surface, a rod for holding a roll of wallpaper, an adjustable stop to accommodate rolls of different widths, and a retainer to hold the wallpaper on a cutting surface adjacent to a slot in the cutting surface which accommodates a knife edge to allow the wallpaper to be severed from the roll with a straight edge.

Abstract: A shingle cutting tool for cutting a shingle having a longitudinal edge, the shingle cutting tool making a cut across the shingle at a selectable angle transverse to the longitudinal edge thereof, the shingle cutting tool including a guide member, the guide member having a substantially upright surface for guiding the longitudinal edge of the shingle, and a cutting assembly, the cutting assembly being pivotally attached to the guide member and extending outward therefrom, the cutting assembly including a cutting base member, a cutting blade, the cutting blade having a cutting edge, the cutting edge opposing the base member, a reciprocating guide mechanism for guiding the cutting blade in a reciprocating fashion within a plane extending from the cutting base, and a pressure mechanism for exerting a pressure on the cutting blade to thereby bring the cutting edge into contact with the cutting base member.

Abstract: A miter saw includes a base on which a work is placed. A miter saw unit supports a saw blade and has a motor for rotatably driving the saw blade. A support mechanism is provided supporting the miter saw unit relative to the base in such a manner that the miter saw unit is laterally leftwardly and rightwardly pivotable from a vertical position. A biasing member is interposed between the miter saw unit and the base for biasing the miter saw unit in a direction opposite to at least one of the directions of the lateral pivotal movement of the miter saw unit when the miter saw unit is laterally pivoted.

Abstract: A saw equipment includes a working table, a rotary arm unit, two adjustment members, a lock unit, a hacksaw, and a guide unit. The rotary arm unit has a rotary arm mounted pivotally on the working table, and two positioning plates respectively secured to two ends of the rotary arm. Each of the positioning plates has several angularly equidistant engaging slots formed therein. Each of the adjusting members includes a lock block and two parallel rods extending upward from the lock block. Each of the lock blocks has several angularly equidistant engaging tongues which engage a first set of the engaging slots of the corresponding positioning plate. The lock unit locks the adjusting members releasably on the rotary arm unit. The guide unit is vertically movable on the adjusting members so as to guide the saw blade to reciprocate on the adjusting members along a straight path.

Abstract: An improved tremolo device for a stringed musical instrument provides a fixed plate attached to the body portion, a fixed gear rack with teeth, and a movable plate that is slideable with respect to the fixed plate and has a bridge member. A pinion gear having teeth around the circumference thereof is provided to mesh with the teeth of the fixed gear rack and to move in unison with the movable plate. A lever is attached to the pinion gear for rotating the pinion gear to change the tension on the strings. The fixed plate has a slot or groove in the face thereof opposite the body, and the movable plate has a slot or groove in the face thereof opposite the fixed plate to form one or more cavities in which anti-friction bearings are encased. In the operation of the tremolo device of the invention, tension in the strings is decreased by depressing the lever which causes pinion gear to rotate, thereby driving the movable plate to cause the tremolo effect when the musical instrument is played.