Abstract: A vibration excited sound absorber for reducing the sound radiation from a vibrating surface. Each sound absorber has a radiating element which is connected to the vibrating surface by a coupling means. The vibrating surface is partially covered with one or more devices. The dynamic response of the sound absorber is tuned so that the volume velocity of the radiating element is substantially equal in amplitude but opposite in phase relative to the volume velocity of the surrounding exposed vibrating surface. The net volume velocity of the surface is thereby reduced.

Abstract: An exhaust system support structure is provided with a vehicle body bracket, a vibration insulating member and an exhaust bracket. The vehicle body bracket has a base part that is coupled to a vehicle body member, and a pair of support parts extending from the base part. The vibration insulating member is coupled between the support parts. The exhaust bracket has a first end coupled to the vibration insulating member and a second end coupled to an exhaust system member. The vibration insulating member includes a housing part that houses the first end of the exhaust bracket. The support parts can be linked together with a linking part. Vibrational displacement of the vibration insulating member is suppressed by a regulating body protruding from the vehicle body bracket side of the vibration insulating member and a regulating body protruding from the linking part side of the vibration insulating member.

Abstract: The drive assembly is formed by an internal-combustion engine which is installed in a passenger car. By means of bearings, supports or the like, the internal-combustion engine is held in position in an assembly space. By means of a wall of a vehicle body, the assembly space is separated from a vehicle occupant compartment. For achieving favorable psycho-acoustic effects, a sound support is provided between the internal-combustion engine and the wall of the vehicle body, by which sound support the engine-mechanical structure-borne sound is transmitted into the vehicle body, specifically for a targeted perception by occupants in the vehicle occupant compartment.

Abstract: A noise reducer for construction machinery, which efficiently reduces noise at low cost with durability, is provided. For this purpose, lamination plates (8) which are the plates being laminated are bonded, discretely at a predetermined interval (a1), to a part of or the entire of a noise generating element. Lamination plates (8A, 8E) may be bonded discretely at a plurality of kinds of bonding intervals (a1, a2). The lamination plates (8) with the different number of laminations may be bonded according to a noise generating element.

Abstract: An aluminum drive shaft includes an aluminum alloy torque tube and aluminum alloy yokes that are pressed into each end section of the torque tube and welded to the end of the torque tube. Each end section is reduced in diameter and joined to a larger central section by a transition section. The end sections and transition sections are formed by swaging the ends of an aluminum alloy tube blank radially inwardly in two stages. The transition sections include an annular rib in the form of a concentric circular band located midway between inner and outer conical portions. The annular ribs stiffen the transition sections to reduce oil canning and noise.

Abstract: An arrangement for acoustically uncoupled mounting of slightly vibrating components on an anchoring part has a first sleeve which is adapted to guide through an opening of a component, a mounting screw which extends through the first sleeve, an uncoupling element adapted to be arranged between the component and the anchoring part, a second sleeve mounted coaxially to the first sleeve, a ring-shaped disc provided on each end of each of the sleeves, so that one of the discs is locatable between the anchoring part and the component at the other of the disc is locatable between the component and a head of the screw, the uncoupling element being adapted to be arranged between the component and a disc facing the anchoring part.

Abstract: A foot device for supporting electronic equipment thereon comprises a sleeve having an axial through bole, and a plurality of balls one by one in line provided in the hole wherein the bottom and top balls are extended above the axial through hole. As such, in use, the electronic equipment is supported by the extended ball of the foot device, while not in contact with supporting plane. This point based contact has the effect of suspending the electronic equipment in the air, thus eliminating interference. Further, the vibration generated by the electronic equipment is not absorbed and interfered by the supporting plane, resulting in a uniform transmission of vibration to all directions without damping or interfering for achieving a maximum quality.

Abstract: This invention provides a muffling panel of a new-type lightweight construction having a function of effectively excluding sounds in low and medium sound ranges and high muffling and sound-absorbing properties in a relatively low frequency band area, and also having at least two parallel diaphragms, a frame body for fixing of the diaphragms and a vibration transmitting mechanism which links to the diaphragms and can mechanically transmit reverse phase vibration, wherein the vibration transmitting mechanism converts vibration of one of the diaphragms which vibrates when receiving a sound into reverse phase vibration thereof to transmit it to the other of the diaphragms, thus causing the other of the diaphragms to displace inward or outward and vibrate simultaneously with one of the diaphragms according to vibration energy of the above original sound.

Abstract: An in-wall speaker has a variably tuned vibration absorber to absorb and dissipate vibrations in the speaker and surroundings that tend to cause distortions. The vibration absorbing device, including a stack of viscoelastic damping plates, is secured to the speaker or connected structure via a trapezoidally shaped tuning plate, which provides a varying degree of cantilever in different portions of the stack of plates. The effect is to absorb vibrations over a broad range of frequencies.

Abstract: A hydraulic pump-motor having an end shield which deadens the sound generated by the pump-motor do thereby result in a quieter unit. The present invention provides a conventional hydraulic pump-motor having an electric motor coupled to a pumping mechanism wherein the motor includes an improved sound attenuating end shield design. Through the use of acoustically deadening materials such as cast iron and polypropylene plastic, the end plates of the present invention deaden the sounds stemming from the vibration of the pump-motor. In addition, the present invention provides an end shield design which allows the stator to be secured to the motor housing and the air gap between the rotor and the stator to be precisely measured prior to the installation of the end shield. The present invention therefore results in not only a quieter pump-motor but also a pump-motor with higher machining tolerances, improved efficiency, and lower production and maintenance costs.

Abstract: A tuned vibration absorber and vibration-reduced pipeline system utilizing same. The tuned vibration absorber includes a support frame, a tuning mass mounted for pivotal movement relative to the support frame about a pivot; the tuning mass including a lever, and a spring contacting the lever. In the vibration-reduced pipeline system, the absorber's support frame is preferably secured atop of the pipeline section, preferably by at least one strap, to absorb vibrations thereof. In a preferred aspect, the tuning mass includes an arm extending from the pivot in a first direction and a weight repositionably mounted thereon. The lever extends from the arm along a second direction substantially orthogonal to the first direction. Preferably the line of action (along A--A) of the spring extends substantially parallel to the first direction. An adjuster is provided for readjusting a position of the tuning mass relative to said support frame due to drift in the spring.

Abstract: A muffler for structure-borne noise of running wheels of different diameters and/or different frequency spectrums of structure-borne sound vibrations has vibration absorbing elements in the form of members which are arranged next to one another in the circumferential direction, forming a circular disk, and are each connected on the base surface in a force-locking manner with the running wheel. The muffler for structure-borne noise consists of at least a first type of vibration absorbing elements which is always the same for a larger range of running wheel diameters, and at least a second type of vibration absorbing elements which is adapted to the respective running wheel diameter and frequency spectrum of structure-borne sound vibrations.

Abstract: The low noise punch tool (17) of this invention includes an upper surface pad (51) formed of a low noise material and disposed on an upper surface of a punch head (37) to be struck by a striker (25) of a punch press. Further, an elastic member (55) formed of a low noise material is interposed between the punch head (37) and a punch guide (43), and a ring (53) formed of a low noise material is interposed between the punch body (39, 41) and the punch guide (43). The low noise punch tool (17) includes a lower surface pad (63) formed of a low noise material and attached to a lower surface of a stripper plate (45) provided at a lower end of the punch guide (43). The low noise material may be urethane. Yet further, the cutting edge (41a) provided at the lower end of the punch body (41) has preferably a shearing angle. This punch tool is advantageous in that the noises of the punch tool during punching is significantly reduced, and the structure thereof is simple.

Abstract: A pulsation damper and noise attenuator assembly comprising a housing having an inlet port and an outlet port fluidly connecting the interior of the housing to the flow path of the fluid flow system. A base is mounted to the housing and comprises a vent fluidly connecting the interior of the housing to the atmosphere. A piston seated within the housing creates a fluid tight seal between the fluid flow path and the vented atmospheric pressure. Belleville springs bias the piston in a forward direction. The piston absorbs the full force of the hydraulic shock waves or pulsation within a high pressure fluid flow system as the assembly is mounted directly within the flow path of the fluid. The shock wave is exposed across the full face of the piston and dampened prior to the fluid continuing along the flow path.

Abstract: A vibration damper includes a suspended mass connected to a pipeline or similar structural member by a support ring and an assembly of interconnected, generally cylindrical damper members formed of an elastomer material suitable to be stressed in shear. The damper assembly is of modular construction so that the damper can be easily tuned to particular frequency and amplitude conditions of different pipes and spans, respectively.

Abstract: A sound- and/or vibration-damping coating, which comprises a layer of a relatively hard substance (2) having pores, interstices, cavities (3) and/or hollows (12) containing a material (4) which has a higher plasticity or elasticity than said substance (2), and an element provided with said coating. This coating may be applied on said element by applying to the surface of the latter a surface treatment ensuring the adhesion of the layer of relatively hard substance (2), by applying this layer to the so treated surface by projection of said substance in the at least molten state and as droplets, by using known per se techniques, and by entering said material (4) into cavities (3) formed between coagulated droplets of said substance (2).

Abstract: A rotary disc for a disc brake assembly in which a pair of nodes or antinodes in all the vibration modes are fixed to rotate integrally with the rotary disc, thereby to prevent a standing vibration mode of all the diametric nodes. A pair of diametrically opposed outer peripheral portions of the disc are made heavier and more rigid than the remaining outer peripheral portions of the disc.

Abstract: Acoustic noises are suppressed in a large format drafting plotter (10) utilizing a paper drive motor (22) mechanically coupled to a paper drive shaft (20) by a geared timing belt (26) from the motor to a pulley (24) on the drive shaft by suitably modifying the pulley. The pulley is modified by enlarging the drive shaft hole (38) in the center thereof so as to provide slip-mounting of the pulley on the drive shaft. A winged clamp (30) is provided, mounted on the pulley, and having a central portion (34) having an opening (36) therethrough for engaging a portion of the drive shaft and a tightening screw (40) for securing the winged clamp to the drive shaft. The winged clamp also has two opposed extensions (42), which are each maintained between a pair of bosses (44) on the outside surface (24a) of the pulley, and isolated therefrom by a pair of isolator pads (32) comprising a compliant material.

Abstract: According to the invention, a resilient element is disposed between interconnected elements on a windshield wiper blade assembly such as cooperating primary and secondary yokes and a wiper blade element. Preferably the resilient element is a tape with a pressure sensitive adhesive backing or a coating that can be sprayed or painted on. The invention also comprehends a method of forming the windshield wiping elements by applying the tape or coating to stock material before the individual elements are stamped and formed.

Abstract: Apparatus for reducing mechanical vibrations in a first part of a structure, in which these vibrations occur through its connection to a part of the structure which is the source of the mechanical vibration. This apparatus comprises an electromagnet rigidly connected to the first part of the structure and a body of magnetizable material connected via a resilient element to the first part of the structure, while an air gap is provided between the electromagnet and the body. The electromagnet is energized by a variable current through at least one coil and it exerts an attractive force on said body which is oscillating due to the vibrations occurring in the first part of the structure. The restoring force exerted by the resilient element on the secondary body has the effect of lowering the resonant frequency of the second body on the resilient element as compared to the resonant frequency of the apparatus when no current passes through the coil.

Abstract: A ventilated disc brake rotor in which spacing between and/or radial length of cooling fins are varied around the rotor for frequency and/or amplitude modulated damping of vibration harmonics, and for balancing the rotor.

Abstract: An ultrasonic sound absorbing material capable of operating at high temperatures and pressures, said material comprises a dense, rigid, permeable material such as sintered metal filled with a viscous fluid.

Abstract: In a vibration absorber for resonance vibrations of rotating bodies, in particular rail wheels, comprising several oscillatory plates which establish a damping mass; intermediate layers of damping material separating the plates from each other; a fastener connecting the plates with the rotating body at at least one point and an intermediate layer of damping material coupling the plates over a large remaining area to the rotating body the geometric dimensions of the plates and the intermediate layers and the Shore hardness of the damping material of the intermediate layers is selected such that all plates oscillate at a natural frequency of the rotating body to be damped, but with the amplitudes and phases of the vibrations of the individual plates differing in such a manner, with respect to one another, that the damping material is as strongly distorted as possible.

Abstract: A vibration damping device for a body resonant at two frequencies, is formed by a plate which can be connected to the body transversely with respect to its vibration direction. A post extends from the plate and mounts one end of an elastically flexible tongue which extends from the post substantially parallel to the plate so as to form a space between the tongue and plate. A weight is fixed to the other end of the tongue and vibration damping material is positioned in the space. The tongue and weight form a system resonant at both of the bodies' resonant frequencies, the tongue's energy being absorbed by the damping material.

Abstract: A system comprising a rail wheel and rail has the wheel and preferably also the rail provided with vibration dampers which absorb vibration having the frequency of the radial resonant vibration frequency of the wheel, for the purpose of preventing the formation of ripples in the rail head's surface on which the wheel runs.

Abstract: A vibration absorbing track wheel having one or more different natural frequencies. The wheel body has a wheel flange with one or more resonance absorbers on the wheel flange. Each resonance absorber comprises at least two tongues and an intermediate layer of damping material between each of the two adjacent tongues, and each tongue is turned to a different natural frequency of the wheel.

Abstract: A non-contacting damping method and means for reducing vibrations in, and noise radiation from vibrating mechanisms, particularly saws and other mechanical members or materials with acoustically radiating surfaces that may be required to move with a substantially frictionless relation to the damping means is disclosed.