Abstract: A muffler responsive to exhaust flow rate is provided for an internal combustion engine. The muffler includes a body having a variable restrictor located downstream from an inlet port and upstream from an outlet port of the muffler. The variable restrictor includes a valving element with an operative position which varies as a function of engine exhaust flow rate to occlude exhaust gas flow. The variable restrictor is formed with a solid wall disposed about the valving element to define a constricting annular passageway having a cross section that varies with distance from the inlet port and from the outlet port. The passageway cross section for some mufflers will increase in a direction proceeding from the inlet port toward the outlet port, and will decrease proceeding in that same direction in other mufflers, depending upon the type of internal combustion engine employed.

Abstract: Disclosed is an automobile muffler having a drain pipe communicating with the upperstream, upper half inside sound-deadening area of its outer pipe, thereby allowing the moisture of the air drawn into the sound-deadening space to leave for the surrounding atomosphere via the drain pipe prior to condensation of the moisture to water in the sound-deadening space, thus making it unnecessary to drain water from the muffler.

Abstract: A tail pipe structure of a control type muffler having a first outlet pipe and a second outlet pipe provided with a control valve inserted therein, wherein the first outlet pipe is in communication with the downstream side of the control valve of the second outlet pipe. The mechanism of the muffler is such that when the control valve is opened, the exhaust gases flow into the atmosphere from the first and second outlet pipes. Further, even when the control valve is closed, the exhaust gases in the first outlet pipe flow into the atmosphere therethrough while a part of the exhaust gases flow into the second outlet pipe from the first outlet pipe through the communication pipe and is then discharged into the atmosphere.

Abstract: Hydraulic clatter damping device consisting of a piston mechanically connected to a valve spindle and sliding within a closed composite chamber (20) consisting of two sub-chambers arranged on either side of the piston, namely, a large sub-chamber (23) in the upper part and a compression chamber (24) in the lower part, both chambers being filled with the same hydraulic fluid under pressure, the piston being provided with a hollow deformable body filled with a gaseous fluid, being rigidly connected to its free face in the large sub-chamber and contracted during rest by the pressure prevailing in the sub-chambers. The sub-chambers communicate with a thin-walled nozzle (26), the chamber containing the hollow body comprising a visual communication means which permits its upper face to be observed. The invention relates to the manufacture of safety valves and other safety components.

Abstract: A sound attenuator may be directly threadedly connected to the exhaust port of a pneumatic device whose exhaust air is to be attenuated. A fail safe blowout plug is provided in the attenuator at the end remote from the exhaust port connection. A cartridge screen covering exhaust slots in the attenuator wall is trapped within an annular groove in the end of the attenuator remote from the exhaust port connection. The screen overlies a protective cover within the attenuator which extends over the blowout plug.

Abstract: An engine exhaust accessory unit comprises a tubular housing adapted to be fitted over the end of an exhaust header. The outer end of the tubular housing is partially obstructed by a pivotable rigid perforated plate. The plate is pivotally mounted about a transverse axis offset below the central longitudinal axis of the housing. The larger upper section of the plate causes it to swing outward in response to passage of exhaust gases through the housing. The perforated plate automatically modifies engine noises and varies exhaust back pressure as a function of its angular position about the transverse axis. A yieldable spring biases the plate to a perpendicular position across the housing, and resists pivotal movement of the butterfly plate in response to passage of exhaust gases. Stops in the path of movement of the plate limit its movement between a perpendicular position across the housing and a position parallel to the longitudinal central housing axis.

Abstract: A silencer for a pneumatically operated hydraulic jack equipped with an air motor is provided. The silencer comprises a first low-pressure chamber formed contiguously to the rear wall of the main cylinder of the air motor, a second low-pressure chamber formed contiguously to and behind the first low-pressure chamber, a baffleplate partitioning the first and second low-pressure chambers and having two groups of first holes formed at an angular displacement of 90 degrees from a pair of discharge holes formed diametrically opposite to each other and radially so as to discharge high-pressure air from the main cylinder of the air motor into the first low-pressure-chamber, and two groups of second holes formed at an angular displacement of 90 degrees from the two groups of the first holes respectively in the rear wall of the second low-pressure chamber to discharge air into the atmosphere.

Abstract: A pulsation dampener and acoustic attenuator for hydraulic systems is designed to be inserted into a liquid flow line. The dampener is a flow-through device with a pressurized bladder restrained within a perforated sleeve. The arrangement of inlet/outlet ports, the bladder, and the screen provides means for dampening flow pulsations in the supply system to effect a more uniform flow and to attenuate acoustic noises reverberating within the system. The dampener provides for self-cleaning due to the flow of the liquid and is thus suitable for sanitary applications. Further, the bladder may be readily removed through one end of the dampener without otherwise removing the dampener from the pipeline in order to examine or replace the bladder.

Abstract: The muffler comprises a resonator (6) which communicates by way of an outlet orifice (14) with a chamber (5). A flexible valve member (16) regulates the section of the passage through this orifice in accordance with the rate of flow of the gas through the outlet of the resonator under the action, for example, of the pressure prevailing in the resonator. When the running speed of the engine decreases, the valve member reduces the section of the passage through the orifice (16) and modifies the acoustic attenuation in the resonator. The valve member may be controlled by other parameters of the flow of the exhaust gas inside the muffler.

Abstract: A device for treating flowing working gases in order to reduce their operational noises and in most instances also to increase their operating efficiency comprises a flowing working gas operating device which has a discharge conduit with at least one discharge opening for the outflow of the working gas. A check valve is associated with the discharge and includes an elastic valve member movable to close the opening when the flow thereof decreases to a predetermined amount for example as determined by the reduction of pressure of the gases so as to prevent any back flow into the conduit which is likely to produce noise.

Abstract: An insert type attenuator arranged to function as a broad-band frequency rejection filter for pulsations in a liquid in a conduit, such as a liquid stock suspension being fed via a pipe line to a paper making headbox, which includes a housing, a conduit positioned within the housing, and a flexible diaphragm having a pair of substantially horizontal spaced runs positioned in the conduit, with means for flowing the stock suspension through the conduit, and means for introducing pressurized gas into and bleeding gas from the housing and the space between the diaphragm runs. Valve means operate intermittently in response to gross outward deflection of one or both of the runs, caused by long-term liquid pressure decreases and/or gradual increases of gas pressure build-up, to vent gas from between the runs and from the housing, and thus to maintain adequate matching of the pressures of the gas cushion and of the liquid.

Abstract: A muffler construction, particularly for exhaust gases of air-operated tools, comprises, a tubular sleeve having a passage therethrough, an exhaust gas pipe connected into the sleeve and defining a restricted flow passage with the sleeve, first and second opposed cylindrical coaxial shell sections, each having a closed end wall at their respective outer ends and facing in opposite directions engaged with the exhaust gas pipe, and sidewalls spaced radially outwardly from the sleeve. The exhaust gas pipe has a gas pipe discharge and there are partition walls in the shell sections defining a first expansion chamber and at least one additional expansion chamber. A constricted flow passage is defined between the first expansion chamber and the at least one additional expansion chamber with sealing and enclosing members closing the sidewalls of the first and second shell sections so as to define the first expansion chamber and at least one additional expansion chamber within the shell sections.

Abstract: A reed valve assembly in which a gummous material coating is applied to the noise-propagating passageway of a secondary-air exhaust gas recombustion system for internal combustion engines.

Abstract: An exhaust muffler intended for noise dampening of, for instance, pneumatic tools, comprising a variable flow restricting passage, an attenuation chamber and a non-variable flow restricting passage. A valve body is arranged to control said variable flow restricting passage in response to the actual exhaust gas pressure. A movement dampening chamber, partly defined by the valve body, communicates with the atmosphere through a restriction opening to prevent resonance vibration of the valve body.

Abstract: A free delivery controlled return valve, of the type employed in fluid power hoisting apparatus, which controls the speed at which a load is lowered as a function of load magnitude. An improved valve structure is disclosed which overcomes false load signals, such as those generated when the hoisting apparatus' lift cylinders are fully extended against a stop, and which thus permits the load platform to descend at an appropriate speed. An improved fluid sonic muffler is also disclosed.

Abstract: When exhaust gases reach an abnormally high temperature, a bimetal valve opens and the muffler operates abnormally to produce a loud noise.