Abstract: A muffler for an exhaust gas system of an internal-combustion engine has an exhaust gas inlet and a first flow pipe arranged inside the muffler and completely penetrating the muffler. A shut-off device is arranged in the first flow pipe, for the shutting-off and opening-up an exhaust gas tail pipe which is situated downstream of the muffler and is connected with the first flow pipe. A second flow pipe partially penetrates the muffler, and has an overflow path between the first and second flow pipes situated inside the muffler. The first and the second flow pipes are connected with the exhaust gas inlet by way of a branching element and the shut-off device is arranged upstream of the muffler in the first flow pipe.

Abstract: A powertrain control system is provided that includes an engine having multiple cylinders. A controller selectively activates the cylinders to provide a cylinder combination having a desired power displacement. In one example powertrain control system, the controller selectively activates the cylinders between a V-8 and V-4 mode. An exhaust system having a valve and an electrical actuator selectively electrically actuates the valve in response to the controller between multiple positions. The electrical actuator moves the valve from an open position in V-8 mode to a partially closed position in V-4 mode to increase back pressure and reduce NVH issues in V-4 mode. A muffler includes a housing having an exhaust passage. The valve is supported by the housing and arranged in the exhaust passage. The valve is moveable between multiple positions for tuning the muffler. The electrical actuator is supported by the housing to actuate the valve between the multiple positions.

Abstract: An exhaust gas control valve includes a valve seat, a valve plate having a first exhaust gas pressure receiving area corresponding to an opening area and a second exhaust gas pressure receiving area larger than the first area; and a spring for closing the valve. In a closed state, gas pressure during a low engine speed operation acts on only the first exhaust area for shutting the opening. In an intermediate state, the pressure during a the middle engine speed operation acts on the first and second areas for opening the opening but closing the valve by overlap of wall portions of the valve plate and the valve seat overlap. In an opening state, the pressure during a high engine speed operation acts on the first and second areas for forming a gap between the wall portions to pass the gas therethrough.

Abstract: A motorcycle, having both left and right mufflers, has an exhaust structure which enables an increase in the allowable margin through which the rear wheel is permitted to rise. A main exhaust pipe extends from an engine to one side of a shock absorber disposed on the rear side of the engine. The main exhaust pipe is branched in the vicinity of the shock absorber into a first branch pipe and a second branch pipe. The first branch pipe is connected to a first muffler disposed on the same side as the main exhaust pipe, and the second branch pipe is connected to a second muffler after passing between the shock absorber and a rear wheel to the opposed side of the vehicle body. The second branch pipe does not interfere with the rising motion of the rear wheel, and a sufficient allowable margin is secured for the rear wheel.

Abstract: An exhaust pipe structure improvement includes a bifurcation pipe, a first muffling pipe, a second muffling pipe, a control device and a heat-insulating block. One end of the bifurcation pipe is divided into a first branch pipe and a second branch pipe, the first muffling pipe and the second muffling pipe are separately connected with the first branch pipe and the second branch pipe of the bifurcation pipe, the second muffling pipe has a valve piece therein. The control device is installed on one side of the second muffling pipe for controlling the valve piece to open or close an exhaust section of the second muffling pipe, and the heat-insulating block is clipped between the control device and the second muffling pipe for controlling the control device without easily being burnt out and effectively controlling exhaust volume of the exhaust pipe so as to increase practicability of the exhaust pipe.

Abstract: Method and device for a particle filter for an exhaust system for a combustion engine, wherein the filter is regenerated by spontaneous combustion of particles accumulated in the filter. Exhaust gases from the combustion engine are led, during operation, past the filter when the counterpressure in the exhaust gases which is caused by the filter exceeds a certain level. The invention also relates to a silencer in a vehicle which is driven by the combustion engine.

Abstract: The invention concerns diesel particulate filter regeneration in an exhaust system of a vehicle having a diesel engine. The particulate filter regeneration is selectively accomplished by actuating a particulate filter backpressure valve located downstream of the diesel particulate filter. Exhaust noise is attenuated for both normal driving and regeneration modes of operation by directing the exhaust flow through different flow paths in a muffler downstream of the diesel particulate filter.

Abstract: To provide a motorcycle exhaust system, which is less susceptible to the elevated temperature of the exhaust gases and vibrations induced by the motorcycle combustion engine (E) and in which the sectional area of the exhaust passage can be properly adjusted independence on the operating condition of the motorcycle combustion engine (E), the motorcycle exhaust system includes a motorcycle combustion engine (E) mounted at a location generally intermediate between front and rear wheels (3 and 9), an exhaust passage fluidly connected at one end with an exhaust port of the motorcycle combustion engine (E), a silencer (17) fluidly connected with the opposite end of the exhaust passage and supported by the motorcycle frame structure (FR) at a location generally above the rear wheel (9); and an exhaust control valve (24) disposed in an inlet of the silencer (17) for variably adjusting the sectional area of the exhaust passage.

Abstract: A muffler to be coupled to the engine of a motor vehicle (e.g., a car, truck, motor cycle, boat, and the like) so that exhaust gases emitted by the engine can be exhausted to the atmosphere. The muffler includes an outer cylindrical body and an inner cylindrical liner having a plurality of apertures formed therethrough. Sound absorbing packing material is located in an annular space between the outer body and the inner liner. An adjustable butterfly valve is located within the inner liner and rotatable between open and closed positions to control the gas flow through the liner, the sound generated by the muffler as a result thereof, and the performance of the engine to which the muffler is coupled. The rotation of the butterfly valve is controlled by an external DC motor or a continuous cable. The shaft of the motor or the cable is connected through the outer body and inner liner of the muffler to the butterfly valve.

Abstract: Exhaust passage control valve 10 may comprise housing 30, valve member 20, and helical torsion spring 40. Housing 30 has an exhaust passage. Exhaust gas from an internal combustion engine flows through the exhaust passage of the housing 30. Valve member 20 opens and closes the exhaust passage of the housing. Helical torsion spring 40 may be disposed at the opposite side of the valve member from the housing side thereof. Helical torsion spring 40 comprises a coil part wherein spring wires have been wound in a coil shape, and arms formed at both ends of the coil part. The coil part may be disposed at approximately the center of the valve member. When the arms bend with respect to the coil part, the counter-force of this bending energizes the valve member towards a closing side. The spring mounting member may be arranged and constructed to adjust a position in which the spring mounting member is mounted on the housing such that a rotation angle of the arms can be changed.

Abstract: A device for active noise reduction has a chamber, which is arranged laterally in relation to a gas flow, and a chamber opening constructed in one wall of the chamber. In the area of the chamber opening, a deflection device is adjustably arranged. The deflection device, in a first position, at least partially directs the gas flow running by the chamber opening into the chamber, in order to compress air there, and, in a second position, directs the gas from the chamber to the gas flow, in order to release the gas inside the chamber. The resulting alternating pressure inside the chamber is radiated through the chamber opening as sound and overlays the disturbing sound.

Abstract: A flapper finger valve assembly for use in an exhaust system. The flapper finger valve includes a tube having a plurality of orifices therethrough. The flapper finger valve assembly also includes a plurality of flapper finger valves generally having a C-shape wherein the flapper finger valves are arranged on an outside surface of the tube. The flapper finger valves are capable of radial movement with respect to the tube. A plurality of retainers generally having a C-shape are arranged around the flapper finger valve. These retainers will define a maximum radial movement for such flapper finger valves on the tube. The flapper finger valve assembly also includes a fastener which will secure the flapper finger valves between a tube and retainers in the flapper finger valve assembly.

Abstract: A muffler with variable acoustic properties. A pressure cell with a diaphragm, a spring, a piston, a piston rod, a closing element on the piston rod, and a pressure connection line are integrated into a housing. The diaphragm is thermally insulated against the piston rod. Another layer of thermal insulation is provided between the closing element and the pressure cell.

Abstract: A system for attenuating exhaust noise from an engine with a first group of active cylinders and a second group of deactivatable cylinders includes a first exhaust manifold connected to the first group of active cylinders and a second exhaust manifold connected to the second group of deactivatable cylinders. The second exhaust manifold is connected to the first exhaust manifold such that the second exhaust manifold acts as a resonator to attenuate sound from the first group of active cylinders when the second group of cylinders is deactivated.

Abstract: A valve device for a silence opens a bypass passage provided in the silencer to flow exhaust gas through the bypass passage when exhaust gas pressure rises to a certain pressure. The valve device includes a base having a valve opening through which exhaust gas flows, and a plate-like valve for opening and closing the valve opening. The plate-like valve is fixed to the base at its proximal portion, and is bent at both edges thereof in a certain range extending from its distal end toward the proximal portion.

Abstract: An exhaust gas system for an internal combustion engine, in particular, of a motor vehicle has two mufflers through which the exhaust gas is able to flow in a parallel fashion. A switching unit makes it possible to selectively convey the exhaust gas flow of the internal combustion engine only or almost exclusively through the first muffler, or only or almost exclusively through the second muffler, or through both mufflers in a parallel fashion. The two mufflers are realized differently with respect to their muffling effect and/or flow resistance.

Abstract: A muffler comprises a casing and an exhaust pipe penetrating the casing. An exhaust gas chamber 4 is defined between the outer wall surface of the exhaust pipe and the inner wall surface of the casing. In the exhaust pipe positioned in the casing, an enlarged chamber for accommodating a particulate filter is formed. A downstream side portion of the exhaust pipe and the exhaust gas chamber are communicated with each other by a branch pipe. A communicating port is formed on the wall of an upstream side portion of the exhaust pipe positioned in the exhaust gas chamber. Until the pressure difference between the upstream and downstream of the communication control valve reaches a threshold value, the communication control valve is kept closed to close the communicating port and, thus, the exhaust gas flows through the particulate filter.

Abstract: A flapper finger valve assembly for use in an exhaust system. The flapper finger valve includes a tube having a plurality of orifices therethrough. The flapper finger valve assembly also includes a plurality of flapper finger valves generally having a C-shape wherein the flapper finger valves are arranged on an outside surface of the tube. The flapper finger valves are capable of radial movement with respect to the tube. A plurality of retainers generally having a C-shape are arranged around the flapper finger valve. These retainers will define a maximum radial movement for such flapper finger valves on the tube. The flapper finger valve assembly also includes a fastener which will secure the flapper finger valves between a tube and retainers in the flapper finger valve assembly.

Abstract: A muffler with variable acoustic properties. A pressure cell with a diaphragm, a spring, a piston, a piston rod, a closing element on the piston rod, and a pressure connection line are integrated into a housing. The diaphragm is thermally insulated against the piston rod. Another layer of thermal insulation is provided between the closing element and the pressure cell.

Abstract: The Invention relates to mufflers with variable damping characteristic for motor vehicles with internal combustion engine, comprising a housing (20) with at least one gas pipe (1), terminating in the housing (20), and at least one valve whose closure element (3) closes the end (2) of the pipe (1) in rest position. The closure element (3) is a disk, seated on a guide rod (4). The guide rod (4) is guided in a guide sleeve (5) and performs a lifting mouvement. The spring (8) is positioned in a valve housing (10) which is gastight and connected in gastight manner to the muffler housing (20).

Abstract: A flapper finger valve assembly for use in an exhaust system. The flapper finger valve includes a tube having a plurality of orifices therethrough. The flapper finger valve assembly also includes a plurality of flapper finger valves generally having a C-shape wherein the flapper finger valves are arranged on an outside surface of the tube. The flapper finger valves are capable of radial movement with respect to the tube. A plurality of retainers generally having a C-shape are arranged around the flapper finger valve. These retainers will define a maximum radial movement for such flapper finger valves on the tube. The flapper finger valve assembly also includes a fastener which will secure the flapper finger valves between a tube and retainers in the flapper finger valve assembly.

Abstract: A controllable muffler system is sued for use with an engine that produces a power by burning fuel. The system comprises a first passage section extending from the engine for having an exhaust gas of the engine flow therethrough. The first passage section has a catalytic converter mounted thereon. The system further comprises a dual passage section including second and third passage sections which extend separately from an end of the first passage section. The second passage has a control valve for controlling the flow rate of the exhaust gas flowing therethrough. The system further comprises a fourth passage section extending from respective ends of the second and third passage sections to the open air. The fourth passage section has a rear muffler mounted thereon. The system further comprises a control unit which controls the control valve of the second passage section in accordance with an operation condition of the engine.

Abstract: A valve device for a silence is disclosed. The valve device opens a bypass passage provided in the silencer to flow exhaust gas through the bypass passage when exhaust gas pressure rises to a certain pressure. The valve device includes a base having a valve opening through which exhaust gas flows, and a plate-like valve for opening and closing the valve opening. The plate-like valve is fixed to the base at its proximal portion, and is bent at both edges thereof in a certain range extending from its distal end toward the proximal portion.

Abstract: A suction muffler in a reciprocating compressor is installed over a suction valve to attenuate complex sound pressure (noise) such as vibrational noise, valve sonance, flowing noise and pulsative noise produced from the suction valve when low temperature, low pressure refrigerant gas ejected from an evaporator is sucked into a cylinder via the suction valve and a suction portion of the cylinder. A Tesla valve having two distribution paths is mounted in the suction muffler to attenuate the complex sound pressure (noise) while preventing the reflow of the refrigerant gas into the suction muffler from the suction valve. As a result, the Tesla valve also enhances the cooling ability of the compressor and the attenuation effect.

Abstract: A muffler comprises a casing and an exhaust pipe penetrating the casing. An exhaust gas chamber 4 is defined between the outer wall surface of the exhaust pipe and the inner wall surface of the casing. In the exhaust pipe positioned in the casing, an enlarged chamber for accommodating a particulate filter is formed. A downstream side portion of the exhaust pipe and the exhaust gas chamber are communicated with each other by a branch pipe. A communicating port is formed on the wall of an upstream side portion of the exhaust pipe positioned in the exhaust gas chamber. Until the pressure difference between the upstream and downstream of the communication control valve reaches a threshold value, the communication control valve is kept closed to close the communicating port and, thus, the exhaust gas flows through the particulate filter.

Abstract: An exhaust system provides the benefits of equal or near equal length exhaust pipes for vehicles (for example with transverse engines) having differing length exhaust pipes connected with a single muffler. In accordance with the invention, the muffler has separate first and second internal inlet pipes which have lengths differing by a predetermined length dimension equal or nearly equal to the difference in exhaust pipe lengths. The inlet pipes are connected so that the total lengths of the pairs of inlet pipes and connected exhaust pipes provide a total length of exhaust flow path which is generally equal for gas flow from both engine banks to the interior of the muffler. An optional feature is dual restricted and valve-controlled outlet flow paths which maintain a minimum back pressure at low flows to aid EGR distribution and allow high flow rates at low back pressure for high performance output of the engine with a performance sound.

Abstract: A device for silencing a flowing gas which includes a valve housing in which a valve is mounted. A separate pressure regulator is provided which is in communication with the flowing gas and which is responsive to gas pressure to thereby influence movement of a mechanical actuating device which controls movement of the valve such that the valve may be opened at least two different rates dependent upon the pressure of the flowing gas.

Abstract: A valve for a control muffler includes: a valve element which is swingably journaled on a support shaft 5 supported by shaft holes 41a of a pair of first shaft supporting portions 41 inside the support shaft 5; bushes 6 which are respectively interposed between the support shaft 5 and a pair of second shaft supporting portions 33 that are disposed on the valve element to pivotally support the support shaft 5; and a coil spring which urges the valve element in a valve closing direction. In the valve, a welding rising portion 41b which protrudes in the axial direction is disposed on an outer opening edge of the shaft hole 41a of each of the pair of first shaft supporting portions 41, and the support shaft 5 is welded to tip ends of the welding rising portion 41b.

Abstract: A device for a sound-absorbing unit for reduction of sounds from a flowing gas stream, including a first flow path and a second flow path for said gas stream and a switch-over device for alternating guiding of the gas stream along the first flow path and the second flow path, respectively. A detection device for detection of the pressure of said gas stream, and that the switch-over device comprises an adjustable throttle for blocking of the first flow path when a pressure which is below a predetermined limit value is detected, wherein the gas stream is guided through said second flow path, and that the throttle is adapted to be opened if said limit value is exceeded, wherein the gas stream is guided along said first flow path. By means of the invention, an improved adjustable device is provided for mufflers for vehicles, said device providing an effective sound absorption, a small mounting volume and a low back pressure during high engine speeds.

Abstract: A method and system for attenuating noise including arranging a plurality of accumulators (210, 310) to form a transmittance path for compressible flow mass and noise between a noise source (212, 312) and the external environment (218, 318), and selectively accumulating and confining compressible flow mass and noise within at least one of the plurality of accumulators, and attenuating noise confined within the at least one accumulator by ringdown. The system may include a plurality of interruptors/valves (220, 320) which are operated at respective timings for periodically accumulating and confining compressible flow mass and noise in at least one of the plurality of accumulators.

Abstract: A valve for a control muffler includes: a valve element which is swingably journaled on a support shaft 5 supported by shaft holes 41a of a pair of first shaft supporting portions 41 inside the support shaft 5; bushes 6 which are respectively interposed between the support shaft 5 and a pair of second shaft supporting portions 33 that are disposed on the valve element to pivotally support the support shaft 5; and a coil spring which urges the valve element in a valve closing direction. In the valve, a welding rising portion 41b which protrudes in the axial direction is disposed on an outer opening edge of the shaft hole 41a of each of the pair of first shaft supporting portions 41, and the support shaft 5 is welded to tip ends of the welding rising portion 41b.

Abstract: A valve in an exhaust gas muffler device of a motor vehicle with exhaust gas conducting openings connecting the interior of a housing of the muffler device to outward of this housing in which one of the housing openings can be closed with a closure element situated within the housing and displaceably mounted on the housing. When the opening is closed, the closure element sealingly abuts on the edge of the opening. The displacement axis of the closure element runs perpendicularly with respect to the plane of the housing opening, and the closure element is coupled to a positioning motor.

Abstract: An exhaust passage control valve has a valve element of a spiral shape mounted on a valve seat portion of a housing through which exhaust gases from an engine pass. The valve element is urged by a valve spring in a direction of closing the valve. A spring constant of the valve spring is kept low without enlarging the valve spring, and there can be obtained opening and closing characteristics in that the valve opens at a stretch when an exhaust-gas pressure has reached a predetermined value. As the valve spring, a helical torsion spring having a coiled cylindrical body portion is used. Arm portions on both ends of a coiled cylindrical body portion are engaged with a pair of spring receiving members. The spring receiving members are disposed in the housing on circumferentially opposite sides of the valve seat portions. The arm portion are engaged with the spring receiving members so as to be slidable in a longitudinal direction of the arm portions.

Abstract: A variable exhaust resonance chamber valve system for internal combustion engine. The engine includes a cylinder having an exhaust port with an axial extent along the axis of the cylinder structure. An exhaust passage having a resonance port extends from the exhaust port to exhaust the engine. A resonance chamber extends from the resonance port and communicates with the exhaust passage through the resonance port. A port valve is adjustable between a second position, in which the port valve exposes the exhaust port throughout its axial extent and occludes the resonance port, and a first position, in which the port valve restricts the axial extent of the exhaust port and exposes the resonance port. A valve control module is connected to the port valve and functions to adjust the port valve between first and second positions in response to engine conditions. At low speeds and low output conditions, the valve is in its first position.

Abstract: In a muffler, a first exhaust outlet pipe has an opening-closing device, and a second exhaust outlet pipe is connected or joined to the first exhaust outlet pipe at a downstream portion of the opening-closing device. An overall length of the second exhaust outlet pipe is greater than the distance between the above joint portion, at which the second exhaust outlet pipe is connected to the first exhaust outlet pipe, and an exhaust inlet end of the first exhaust outlet pipe, and the overall length of the second exhaust outlet pipe is shorter than or generally equal to an overall length of the first exhaust outlet pipe. With this construction, in a low engine revolution speed range, the production of abnormal sounds in the second exhaust outlet pipe is prevented.

Abstract: To a housing having a valve opening which serves as a bypass passage for exhaust gases, there is fixed one end portion of a plate valve which is capable of elastic deformation by deflection. The housing is provided with an enclosing wall which projects in a direction of opening of the plate valve in a manner to enclose the plate valve. A valve opening is formed by an inner peripheral space of the enclosing wall. When the exhaust gas pressure exceeds a predetermined pressure, the plate valve is deformed to a position beyond the open end of the enclosing wall, whereby the valve opening is opened to passage. A plate spring to contact the plate valve is provided. With an increase in the amount of deflection in the opening direction, the position of contact of the plate spring deviates toward a fixing end of the plate valve. The bending moment to be applied to the plate valve in a closing direction decreases.

Abstract: A silencer assembly primarily for the passage therethrough of exhaust gases from an adsorption dryer tower comprises a silencer element to one end of which pressurized gas is directed from an outlet, a control valve downstream of the silencer element, and means for restricting the flow of pressurized gas from the outlet to atmosphere through the silencer element, the arrangement being such that, when the pressure of the gas from the outlet exceeds a predetermined value, the control valve is closed and gas flows from the outlet into and through the silencer element to atmosphere, and, when the pressure of gas from the outlet falls to said predetermined value, the control valve opens and the gas flows from the outlet through the control valve to atmosphere, by-passing the silencer element.

Abstract: This invention relates to an exhaust gas muffler assembly for internal combustion engines which is operable in both a muffled or unmuffled mode. In exterior appearance, the bypass muffler of this invention looks like a conventional muffler having a shell and end caps which enclose the interior components, an inlet for entry of the exhaust gas from the engine, and two outlets for exit of the exhaust gas to atmosphere. A first outlet is preferably positioned opposite to the exhaust gas inlet and connected directly to the inlet by means of a pipe. This pipe is not provided with silencing means. Within the interior of the muffler are silencing means employing a center pipe and an exhaust gas outlet pipe, each of which are provided with silencing means such as apertures in the walls of each pipe. Flow diverting means are removably placed within the first outlet.

Abstract: A muffler having a movable valve disk, with the help of which at least one of the tubes in the muffler housing can be opened and closed. The actuation organ for the valve disk is a corrugated tube, the fixed end of which is placed into an opening in the housing and the interior of which is connected to the atmosphere. As a result, the total pressure loss of the muffler is available as an actuation force.

Abstract: An exhaust system includes an exhaust pipe attached to the engine. Attached to the exhaust pipe is a muffler which has an exhaust gas inlet, a plurality of expansion chambers through which exhaust gas flows, and at least one wall between adjacent expansion chambers. There is an opening or orifice in the wall between adjacent expansion chambers. A flap which covers the orifice or the opening in the wall between adjacent expansion chambers. The flap opens in response to a pressurized surge of exhaust gas entering into the expansion chamber. The muffler also has an exhaust gas outlet for allowing exhaust gas to pass from the second chamber of the muffler. The exhaust system typically has a plurality of chambers attached to one another such that the exhaust gas travels along a tortuous path between the exhaust gas inlet and the exhaust gas outlet. The flap is pivotally attached to the wall between adjacent expansion chambers. The flap is also positioned so that it closes due to gravitational forces.

Abstract: A muffler includes a housing and one or more tubes secured in the housing. A valve member is engaged in each of the tubes for adjusting an opening size of the tube and for adjusting the pressure that may be generated in the housing such that the mufflers may be secured to various kinds of engines. The valve member includes a ball rotatably engaged in the tube and having an orifice for adjusting the opening size of the bore when the ball is rotated. A filter material is engaged in the housing and may be squeezed for adjusting the output noise of the muffler.

Abstract: A hydraulic vibration damper includes a noise-reducing valve structure that isolates the region of cavitation away from the metal structures forming the pressure cylinder, the piston and valve structures. The improved design includes a sharper rebound land edge angle forming a boundary near the valve exit, enlarging the region of working fluid adjacent the valve structure exit within which implosions can take place. This design also dispenses with the use of a skirt around the perimeter of the piston, and removes contact between the piston and the pressure cylinder. A support piston provides contact with the interior surface of the pressure cylinder. These features distance the region of cavitation from metal surfaces of the piston and valve structures, thereby significantly reducing the transmission throughout the vibration damper of noise and vibration caused by implosions within the working fluid.

Abstract: An improved suction noise muffler for a hermetic compressor which is capable of discharging residual oil which is introduced together with a refrigerant gas using the weight of the oil itself by equipping with an oil discharging valve unit at an oil discharging unit, which muffler includes a guide path for guiding a refrigerant gas introduced through an inlet portion along a connected path, resonant and noise reducing chambers formed for reducing noise of the refrigerant gas which flows along the guide path, and an oil discharging section having an upper discharging section in order for the oil introduced into the resonant and noise reducing chambers together with refrigerant gas to be discharged through the discharging valve unit operated by the weight of the oil, with the oil discharging valve unit being formed in the upper discharging section.

Abstract: A plurality of chambers are partitioned in a muffler by a baffle board. The muffler is provided with an exhaust gas passage for discharging exhaust gas outside the muffler via these chambers and a valve that bypasses a part of the exhaust passage. This valve opens according to the exhaust gas pressure. Also provided are a mechanism for pushing the valve in a closing direction, and a mechanism for damping the shock when the valve closes. Thus, valve closing noise is suppressed, and exhaust gas noise is further suppressed.

Abstract: An unbiased valve is located within a muffler. The valve is positioned by the pressure differential across the valve and is either in the full open or full closed position. A pressure equalization tube is provided between the downstream cavity of the muffler and the back of the valve such that flow pattern produced low pressure areas are avoided and the valve can react to actual pressure differentials in the flow.

Abstract: A retrofittable muffler to reduce noise associated with air-operated hand tools and other working devices provides a housing with an inner expansion chamber and an outer expansion chamber so that at least a portion of spent pneumatic fluid passes from the pneumatic device, through the internal expansion chamber, and through the outer expansion chamber prior to discharge to atmosphere through exhaust ports in the housing.

Abstract: A muffler is described for use in connection with an exhaust passage in a ongated shaft rotating about a longitudinal axis. The shaft exhausts exhaust material generated by an internal or external combustion engine, having both a gaseous and a liquid material. The muffler includes a series of partitions situated transverse to the longitudinal axis of the shaft, each partition defining a central aperture to facilitate passage of gaseous material from an input end of the exhaust shaft to an output end of the exhaust shaft, and at least one exterior aperture proximate the sidewall of the exhaust passage to facilitate passage of liquid material from the input end to the output end. The central and exterior passages tend to separate the gaseous and liquid material in the exhaust. The series of partitions define chambers which attenuates the sound energy in the exhaust.

Abstract: An exhaust brake arrangement is provided for selective operation to facilitate braking of a vehicle such as an over-the-highway truck. The exhaust brake operates by selectively generating back pressure to the exhaust flow system, and thus drag on the engine and braking action. The exhaust brake arrangement includes pressure relief valve assembly which regulates the amount of exhaust back pressure build up to release same before design limits are exceeded. In addition the arrangement may include a bypass valve construction for selective positioning of the pressure relief valve assembly on line or off line, as may be desired.

Abstract: A weight biased check valve is located in a reflective muffler at the entrance thereof. As a result, both the check valve and muffler are located proximate to a compressor which minimizes both the package size and the volume trapped upon shutdown. The axis of the weight biased check valve is skewed whereby the weight biasing effect is reduced.

Abstract: A pulsation damper is disclosed for use in a standard air-conditioning compressor for an automobile. The pulsation damper consists of a body portion and a cap portion and the cap portion has an outer diameter that is dimensioned to be press fit within the outlet opening of the housing of the air compressor. Thus, the pulsation damper can be retro-fit in a standard air compressor housing and will not increase the overall size of the housing or require modification in the connecting tubing. The body of the pulsation damper consists of longitudinal groove-like passages which direct the fluid flow from one of two internal compressor discharge lines to a point where it opposes and is intermixed with the fluid flow from another internal discharge line. This opposition and intermixing of the two fluid flow paths, which have pressure pulses which are out of synchronism with each other, tends to cancel or reduce such pulses.