Abstract: A stringed musical instrument having an elongate neck and a body which may have a resonant cavity at one end and a head at the other end thereof. Strings extend across the neck and, when vibrated, generate musical sounds. The invention relies upon fingerboards which are removable so that one type of fingerboard may be substitutable for another type of fingerboard in order to generate sounds of different timber or of different qualities. Thus, fretted fingerboards are substitutable for non-fretted fingerboards. Moreover, and in a preferred embodiment, the fingerboards are inserted onto the neck of the instrument and can be slid into and out of interlocking elements from one longitudinal side of the neck of the instrument. In one embodiment of the invention, dovetail projections are formed on the neck of the musical instrument and corresponding notches or grooves are formed on the underside of the fingerboard to permit an interlocking arrangement of the fingerboard on the neck of the musical instrument.

Abstract: Tubular acoustic attenuation piece for an aircraft jet engine air intake. According to the invention, said tubular piece (1) is made up of shells (2) with a cellular core (5) assembled only by external fish plate strips (8), the facing edges (6) simply being edge faces of said shells (2) forming slots (9) between them.

Abstract: A method for tilting a seat of a vehicle based on a first threshold (low) and a first threshold (high) for a first parameter of the vehicle and a second threshold (low) and a second threshold (high) for a second parameter of the vehicle. The tilt angle of the seat is increased if the first parameter is greater that or equal to the first threshold (low) and the second parameter is greater than or equal to the second threshold (high) or if the parameter is greater than or equal to the first threshold (high) and the second parameter is greater than or equal to the second threshold (low).

Abstract: A sealing and acoustic insulation panel, in particular for automobile vehicle doors, includes a sealing sheet and a layer of acoustic insulation, with a bead of adhesive material on the sealing sheet for fixing the panel to a support plate. A frame for applying pressure to the bead of adhesive material is placed between the sealing and acoustic insulation panel and a trim panel clipped to the support plate.

Abstract: Acoustic diffuser comprising a containing element able to contain at least a loudspeaker, wherein the containing element is formed by a monocoque made with granules of solid mineral held together by a cohesion material.

Abstract: An electrical steering system for a vehicle includes an electrically supplied steering motor arrangement which is connected with an inverter arrangement, whose output voltage is influenced by a computer arrangement, and a sensor arrangement. To reduce the cost of the steering system while also allowing the steering system to be steerable during braking in the case of a fault, the steering motor arrangement has a redundant steering motor which is connected with the computer arrangement via two separately run control circuits. The control circuits have separate electric supplies and the computer arrangement is redundant.

Abstract: An engine noise reduction device to reduce sound output from an engine compartment and supply cooling air to the engine compartment to increase cooling efficiency and prevent engine and component overheating. The device opposes a plurality of air inlets, to receive an air flow therefrom, and includes a split-type noise absorbing portion and a cell-type noise absorbing portion.

Abstract: Disclosed is a method and an apparatus for converting sound/color or color/sound, and more particularly to a method and an apparatus capable of converting a sound into a color image or an image into a sound, by selecting the harmonic color exactly tuned with an optional reference color based on the harmonics, and frequency converting a sound or a color having a characteristic of wave.

Abstract: A motor control method and apparatus produce rapid, point-to-point movement while minimizing settling time and peak power consumption in a servo-control system with a periodic input. Rapid open-loop movement is combined with tuning of the open-loop input based on position and velocity of the output when the loop is closed. Iterative learning control is used to adjust open-loop commands in subsequent cycles to reduce residual vibrations and quickly reach the desired final position. The apparatus and method can be used in motion control applications requiring rapid, periodic, point-to-point movement, such as weather satellite servo systems with a periodic input containing multiple step responses within each period.

Abstract: An improved heat shield provides thermal insulation and reduced noise transmission of vehicular engine components, including exhaust manifolds. The structure has three layers; an outer structural metal layer, a center insulation layer to isolate heat and dampen noise, and an inner metal layer directly adjacent the shielded component for reflecting heat back to the shielded component. The heat shield is attached by bolts to the shielded component. In the described embodiment, the volume of the insulation layer is expanded by approximately 15 to 20 percent over conventional shields to produce a softer, thicker material having a lower density but unchanged mass. The invention provides a technique to achieve desired thickness and density in insulation layers via modal finite element analysis. The relatively thicker heat shield more effectively absorbs vibration and attenuates noise without increase in mass. In the described embodiment, the layer contains cellulose, diatomaceous earth, talc, and fiberglass.

Abstract: An exhaust muffler for a fuel-operated heating device has upper and lower housing half shells, an exhaust gas through-duct and absorption and reflection chambers. The exhaust muffler is connectable to an exhaust pipe of the heating device. The exhaust gas through-duct has an inlet pipe of a single absorption chamber and a single following reflection chamber that are separated by a partially perforated partition, with double reversal of the exhaust gas flow, and an outlet pipe; the inlet pipe being perforated on the outer surface side, with an S-shaped curved section and a straight end section, and the outlet pipe being a straight outlet pipe, closed on the outer surface side, and the straight section of the inlet pipe runs parallel to, and at a spacing from, an inlet section of the outlet pipe.

Abstract: A circuit for the speed recovery of a direct current motor includes an output stage, output stage having a first pair of transistors, a second pair of transistors, and means a first circuit configured to detect a current circulating in the motor. The output stage further includes a second circuit configured to, activate the second pair transistors for a determined first time period so as to short-circuit the motor, and, at the end of the first time period, unbalance the output stage so as to force a maximum current to circulate for a determined second time period as a function of a value detected by the first circuit during the first time period, so as to stop the motor.

Abstract: The servo control method operates a set value of a first-order lag time constant of a feedback compensation by both a detected mechanical position value and a transfer function corresponding to a change of an angular velocity about each axis under a multiple-axes simultaneous control. Further, the servo control method sets a feedforward amount so that the transfer function about the each axis is the same.

Abstract: The invention makes it possible to execute the pre-control and the fine interpolation in the drive (A) in the fast drive clock (tDR) with a slower path pre-setting in the clock (tNC) of the NC. For this purpose, in each NC clock (tNC) a setpoint speed value (nNC*) and the P gain (kP) of the NC position controller (L_NC) and the desired axle speed (nNC) and the average axle speed (nNCMW) during the last NC position controller clock are transferred from the NC to the drive. From this information, polynomial segments of the third degree are in each case generated on the drive side, valid for the duration of an NC position controller clock (tNC). They are constructed in such a way that the speed at the polynomial transitions is constant. A variable component of the position polynomial is determined as the fine position component xF, with which the setpoint position values are finely interpolated in the drive.

Abstract: A vehicle seat includes a seat movable along a path a motor for driving the seat on the path, a sensor generating a signal indicating movement of the seat on the path, and a controller operating the motor to move said seat along the path. The sensor is preferably a Hall-effect device or a potentiometer. The controller is in communication with the sensor to receive the signal and form a feed-back control loop. The controller accelerates the seat at a controlled rate of acceleration to a controlled constant speed and decelerates the seat from the constant speed at a controlled rate of deceleration. The controller controls the rate of acceleration of the seat at a stored predetermined rate of acceleration by adjusting operation of the motor to maintain the predetermined rate of acceleration.

Abstract: A symmetrically loaded, shallow suspension speaker with stiff diaphragm having a minimum dimension that is greater than the diameter of the magnet that drives the diaphragm thus allowing the suspension of the diaphragm to extend nearly to the bottom of the speaker basket on the maximum inward excursion of the voice coil and diaphragm such that the suspension operational depth is not the limiting factor of the overall height of the speaker. The elements of the suspension system are designed to maximize the spacing between the inner and outer portions of the suspension, thus minimizing the possibility of wobble in the speaker. The speaker design maximizes air movement in a given mounting depth with a configuration that optimizes the operation of the moving parts that complements the fixed mechanical structural configuration of the non-moving parts in either an overhung or underhung configuration. The design also accommodates user replacement of the voice coil or cone.

Abstract: A sound-insulating floor structure, which can conspicuously reduce heavy floor impact sounds, is provided. The sound-insulating floor structure includes a floor base and an underfloor member. A plurality of sound-insulating floor members are arranged between the floor base and the underfloor member, and each of the sound-insulating floor members includes a plurality of impact-absorbing members and a support member supporting the impact-absorbing members. The impact-absorbing members are provided at at least one of upper and lower faces of the support member. Each of the sound-insulating floor members is fixed to the floor base or to the underfloor member, thereby supporting the underfloor member.

Abstract: A multi-duct diffusion exhaust device for a turbomachine. The exhaust device including an annular inlet, an outer casing shaped symmetrically overall with respect to an axis, one or more internal partitions defining several roughly concentric ducts for an exhaust stream to flow through, and an absorbent coating capable of absorbing some of the acoustic energy generated by the flow. The absorbent coating being provided on at least one of a surface of one internal partition and an interior surface of the outer casing. The absorbent coating having a thickness that is tailored along a length of the exhaust device to optimize the flow in the ducts by maintaining progressive diffusion and avoiding detachment near stationary surfaces.

Abstract: An arrangement is disclosed for controlling fan motors in fan-powered terminal units which permit the air flow of the terminal units to be factory preset and reset using a voltmeter. The fan motor is responsive to the pulse width of pulses of a pulse width modulated signal to provide an air flow which is proportional to the pulse width. By adjusting the pulse width, the air flow may be set as desired. A pulse width modulated signal having pulses with a set amplitude and frequency is generated. The dc voltage of the pulse width modulated signal is measured using a voltmeter. As the pulses have a set amplitude and frequency, the pulse width of the pulses may be adjusted by controlling the dc voltage of the pulse width modulated signal. The fan motor is programmed to deliver the set air flow over a range of static pressures.

Abstract: An electric motor control circuit that prevents lowering of a motor's rotation speed when a load is applied in the case where a rotation speed is adjusted within a range that doesn't exceed a predetermined upper limit of rotation speed. When a base current of a transistor Q1 starts to flow in response to operation of a trigger switch 3, transistor Q1 turns on and a setting signal output from a switch S2 which sets the upper limit rotation of a motor M is bypassed via a bypass way 22 by transistor Q1. Thus, a signal level of the setting signal inputted to an operational amplifier 7 is changed, and output timing of a pulse signal output from a phase control circuit 5 to a gate pulse output circuit 9 is changed and a conducting angle of a triac Q2 is controlled. Because the trigger switch 3 does not adjust an output level of operational amplifier 7, the rotation speed of motor M does not decrease when the load is applied.