Abstract: A gear assembly includes an actuation gear and plural separate pinion bodies. The actuation gear has first gear teeth on one or more surfaces of the gear and is configured to rotate around an actuation axis of rotation. The pinion bodies have second gear teeth configured to mesh with the first gear teeth of the actuation gear in plural separate mesh zones of the actuation gear. Each of the plural separate pinion bodies are configured to be rotated about respective pinion axes of rotation to cause rotation of the actuation gear around the actuation axis of rotation.

Abstract: In a planetary gear device including: a sun gear; a plurality of planet gears; a ring gear; and a tubular support member connected to the ring gear so as to rotate together with the ring gear; an outward flange provided at the ring gear and projecting radially outward and extend over an entire periphery thereof; an wavy inward flange provided at the tubular support member and having a plurality of projection pieces projecting radially inward over an entire periphery thereof, the outward flange and the inward flange are fastened to each other by means of bolts and nuts, and the inward flange has a plurality of recesses formed between the plurality of projection pieces and the plurality of recesses include shallow first recesses and second recesses deeper than the first recesses such that depth of the recesses becomes greater at regular intervals.

Abstract: A gear ratio mechanism includes an input shaft, a first planetary gear set, a second planetary gear set, and a carrier link associated with an output shaft. The carrier link is configured to couple the first planetary gear set and the second planetary gear set. The carrier link is selectively driven by the first planetary gear set and the second planetary gear set in response to rotation of the input shaft.

Abstract: A dual clutch transmission for a motor vehicle. A gearwheel set switchable via switching elements, which form eight wheel planes and which are respectively assigned to a first sub-transmission and to a second sub-transmission, among which each sub-transmission is provided with an input shaft and both sub-transmissions are provided with a common output shaft. The input shafts, which are coaxial to each other, can be alternately activated via a load-shiftable clutch, and the even forward gears are assigned to the first sub-transmission, while the odd forward gears are assigned to the second sub-transmission, which are shiftable during a gear switch via the switching elements. The input shafts are free of the rotationally fixed gearwheels of the wheel planes arranged thereupon.

Abstract: A dual clutch transmission for a motor vehicle, with gear wheel sets, which can be engaged via shift elements and which, in particular, form eight wheel planes, which are associated with, respectively, a first sub-transmission and a second sub-transmission, each sub-transmission has a respective input shaft and both sub-transmissions have a common output shaft, wherein the mutually coaxial input shafts can each be activated in alternation via a power-shift clutch and the even forward gears are associated with the first sub-transmission and the odd forward gears are associated with the second sub-transmission.

Abstract: A dual clutch transmission for a motor vehicle, with gear wheel sets, which can be engaged via shift elements and which form exactly eight wheel planes, which are associated, respectively, with a first sub-transmission and a second sub-transmission, of which each sub-transmission has a respective input shaft and the two sub-transmissions have a common output shaft, which is axis-parallel to the input shafts. The mutually coaxial input shafts can each be activated in alternation via a power-shift clutch, and the even forward gears are associated with the first sub-transmission and the odd forward gears are associated with the second sub-transmission, which can be engaged when a gear shift occurs via the shift elements.

Abstract: A dual clutch transmission for a motor vehicle, with switchable gearwheel sets which form in particular exactly eight wheel planes (RE-1 through RE-8), which are assigned to a first and to a second sub-transmission. The sub-transmissions are provided with at least one input shaft and with a common output shaft and the input shafts can be alternately activated via a load-switchable clutch. Furthermore, the odd forward gears are assigned to the sub-transmission and even forward gears are assigned to the other sub-transmission, which are switchable by corresponding switching elements. At least one gearwheel set of one sub-transmission can be coupled with a switching element to the other sub-transmission.

Abstract: A drive transmission mechanism includes a first gearbox including a driving source, a first gear train, a first frame configured to support one ends of a plurality of shafts of the first gear train, and a first gear cover configured to support the other ends of the shafts of the first gear train, wherein the first gear box is configured to transmit a driving force from the driving source; and a second gearbox including a second gear train, a second frame configured to support one ends of a plurality of shafts of the second gear train, and a second gear cover configured to support the other ends of the shafts of the second gear train, wherein the second gearbox is configured to receive the driving force from the driving source through the first gear train and configured to transmit the driving force. The second gearbox is fixed to the first gearbox.

Abstract: A transmission system for a work vehicle includes a transmission. The transmission includes a first shaft, a second shaft, an input shaft, an output shaft, and an input gear pair comprising a first input gear and a second input gear. The transmission includes a first input clutch configured to selectively couple the input shaft to the first shaft, and a second input clutch configured to selectively couple the input shaft to the second shaft via the input gear pair. The transmission includes an output gear pair comprising a first output gear and a second output gear, wherein the first output gear is coupled to the first shaft, or the second output gear is coupled to the output shaft. The transmission also includes a first output clutch configured to selectively couple the second output gear to the output shaft, and a second output clutch configured to selectively couple the second shaft to the output shaft.

Abstract: A transmission includes a countershaft, a splitter section having an input shaft and a clutch that couples the input shaft to the countershaft, a main transmission assembly having a main shaft and a main transmission clutch, the main shaft coupled to the countershaft via the main transmission clutch, a range gear assembly having a an annulus gear, a sun gear, a planet gear, and center shaft that provides output from the transmission, and a spline joint that couples the main shaft to the center shaft and in operation transfers torque through and reduces eccentric loads between the main shaft and the center shaft that occur due to axial misalignment.

Abstract: An easily attached and highly tunable spring arrangement for use with existing front end accessory drive automatic belt tensioners is provided. The spring arrangement of the disclosed inventive concept includes an external spring that can be attached to tensioners to provide a specifically desired amount of additional tension. The spring is flat or round and is externally mounted, conforming to the outer dimension of a portion of the tensioner. The spring can be used on existing tensioner-to-engine bosses using conventional fasteners. The spring includes an attachment end and a biasing end. The attachment end includes at least one bolt sleeve that is formed as part of or is fitted to the external spring by welding. The biasing end contacts the outside of the front end accessory drive automatic belt tensioner at an area adjacent the tensioner pulley. The spring length, material and thickness may be varied for proper tension.

Abstract: The disclosure relates to a sliding system for a wraparound transmission for reducing vibrations and undulations of a wraparound means, the sliding system comprising a wraparound means for connecting a transmission input shaft to a transmission output shaft in a torque-transmitting manner. The wraparound means has a plurality of deflecting axes and a height oriented transversely with respect to the deflecting axes. The sliding system also includes a sliding rail which comprises a sliding channel with an inner sliding face and an outer sliding face, wherein the sliding channel defines a running direction for the wraparound means, and the sliding channel being divided in the running direction into an entry section, a main section and an exit section. The sliding channel has a setpoint height adapted to the height of the wraparound means.

Abstract: An object of the present invention is to provide a chain drive device that guides a chain favorably with a chain guide to prevent noise generation and wear or damage of various parts with a simple structure, and to provide the chain guide. Provided is a chain drive device 10 having a guide shoe 40 that includes a shoe surface part 41 and a lip 43. The shoe surface part 41 has a larger widthwise dimension than that of the chain 20. The lip 43 has a front-side lip end 44 which has a lip front end face 44a that faces the front side in the chain running direction. The lip front end face 44a has a height that is set larger than a dimensional difference in backside height between inner plates 21 and outer plates 23.

Abstract: A work vehicle having a belt type stepless speed changing mechanism includes a rotation detecting section for detecting an engine rotational speed, a vehicle speed detecting section for detecting a vehicle speed of a traveling vehicle body and an informing section configured to effect an alarm informing for alarming wear of a drive belt if a vehicle speed detected by the vehicle speed detecting section is a predetermined vehicle speed deviates from a preset permissible range.

Abstract: A planar actuator device, including a base plate including a first, second, and third pair of planar coils, each pair of planar coils having an inner coil and an outer coil, each pair of planar coils arranged along a first, second, and third linear motion axis, respectively, the first, second, and third linear motion axis arranged in a star configuration, and an actuation mechanism including a first, second, and third planar legs and a centerpiece, the first, second and third planar legs pivotably connected to the centerpiece, the planar legs including a first, second, and third sliding element and a first, second, and third middle section, respectively, a sliding element and middle section of a respective leg pivotably connected to each other, each sliding element including a permanent magnet.

Abstract: Linear actuators and methods for assembling the same are disclosed. A linear actuator according to the disclosure may include a drive unit having a drive shaft, and a spindle mechanism having a spindle, which can be driven by the drive shaft. A bearing unit may be provided, which may be configured to support a connecting shaft connecting the drive shaft to the spindle and has a bearing block matched to the internal cross section of the housing. The bearing unit may have a preloading device for preloading a rotary bearing inserted into the bearing block, and the spindle may be screwed to the connecting shaft via a centering portion and a screw fastening portion.

Abstract: A brake arrangement for a gearbox is provided, where the gearbox comprises an input shaft, a counter shaft, a main shaft and a plurality of gear wheels pairs which each comprises a primary gear wheel arranged on the counter shaft and a secondary gear wheel arranged on the main shaft. The brake arrangement further comprises at least two brake units each configured to act with a braking torque on the counter shaft or a component connected to the counter shaft, and a control unit configured to control the activation of the brake units. The control unit is configured to activate the at least two brake units one at a time or both simultaneously during an upshift process in the gear box when a secondary gear wheel of a gear wheel pair to be engaged in the gear box is retarded to a synchronous speed with the main shaft.

Abstract: A stator assembly for a torque converter having an impeller and a turbine includes a one-way clutch. The one-way clutch includes a plurality of rollers arranged radially in a spaced apart relation to one another. Each of the plurality of rollers is biased into a floating position by a corresponding resilient member. The stator assembly also includes a stator wheel mounted on the one-way clutch. A mass of the stator wheel is selected so as to operatively provide a predetermined amount of delay for engaging or disengaging the one-way clutch.

Abstract: A lock-up device includes a clutch part, an input plate, an outer peripheral side damper part, an output plate, an inner peripheral side damper part, and an intermediate member. The outer peripheral side damper part includes at least two outer peripheral side springs. The outer peripheral side springs are disposed in a circumferential alignment, act in series, and take circular-arc shapes when in a free state. The inner peripheral side damper part includes at least two inner peripheral side springs. The inner peripheral side springs are disposed in a circumferential alignment on an inner peripheral side of the outer peripheral side damper part, and act in series. The intermediate member is rotatable relatively to the input plate and the output plate, and makes the outer peripheral side damper part and the inner peripheral side damper part act in series.

Abstract: A method for manufacturing a differential device includes a first step and a second step. The first step is to cast a differential case by pouring molten cast iron into, via a gate, a mold having, on a mold surface, a mark formation site that has a specific positional relationship to the gate. The second step is to fit the differential case with a ring gear and weld the differential case and the ring gear together entirely around a prescribed axis. In the second step, the differential case and the ring gear are welded together using a mark formed on the differential case by the mark formation site in the first step so that an overlap of welding does not occur in a portion of the differential case formed near the gate of the mold.

Abstract: A compound harmonic drive including: a first internal ring gear; a second internal ring gear, the second internal ring gear being coaxial to the first internal ring gear; a first external gear located within the first internal ring gear and coaxial to the first internal ring gear, the first external gear meshes with the first internal ring gear; and a second external gear located within the second internal ring gear and coaxial to the second internal ring gear, the second external gear meshes with the second internal ring gear. The first internal ring gear and the second internal ring gear are composed of a flexible material.

Abstract: A compound harmonic drive including: a flexible ring having an inner surface and an outer surface; a first flexible gear disposed around the outer surface of the flexible ring and coaxial to the flexible ring; a second flexible gear disposed around the outer surface of the flexible ring and coaxial to the flexible ring; a first ring gear that meshes with the first flexible gear and is coaxial to the first flexible gear; and a second ring gear that meshes with the second flexible gear and is coaxial to the second flexible gear. The first flexible gear and second flexible gear are fixedly attached to the outer surface of the flexible ring.

Abstract: A composite camshaft is made by simultaneous through transmissive laser welding cams, bearing assemblies and load introduction parts to a fiber composite support tube.

Abstract: A rope control device a main body defining a central opening and first and second side portions, projections extending from the main body, an end recess defined by the first and second projections, an end friction surface formed at a juncture of a projection and the main body, and a bar. With the bar in a first position, the first rope portion is extended through the central opening and at least partly around the bar. With the bar in a second position, the main body and the bar define first and second opening portions of the central opening and the first rope portion is extended through the first and second opening portions and at least partly around the bar. The second rope portion is arranged within the first end recess such that, when the rope is under tension, the second rope portion frictionally engages the first end friction surface.

Abstract: A measuring system for detecting variables on planet carriers of a planetary gear train having a plurality of planetary gear stages includes a first sensor which is arranged on one of the planet carriers of one of the planetary gear stages for detecting the variables of a planet gear rotationally connected to the at least one of the planet carriers. An electronics configured for arrangement on the planetary gear train is operably connected to the first sensor for supply of the first sensor with electrical energy.

Abstract: A linear actuator is disclosed having a housing and a plurality of components arranged in the housing. The actuator may include at least one conducting component, a group of mechanical, non-conducting components including components of a spindle mechanism, and at least one bearing arrangement designed to support components of the spindle mechanism in the housing. The at least one conducting component may be separated from the group of mechanical, non-conducting components by at least one seal in such a way that two mutually separate spaces sealed off from one another are formed within the housing.

Abstract: A vehicle, system, and method of warming the transmission fluid with a thermoelectric generator is also provided. Disclosed is vehicle having an internal combustion engine, a transmission containing a transmission fluid, a coolant circuit configured to remove heat from the engine, and a thermoelectric generator. The thermoelectric generator is in non-contact thermal communication with the hot exhaust gas produced by the engine and the relatively cooler coolant circulating through the coolant circuit. The thermoelectric generator produces a current from the temperature gradient between the exhaust gas relative and coolant and transfers heat from the exhaust gas to the coolant. The heat coolant is conveyed to a transmission heat exchanger to heat the transmission fluid. A heating element is disposed in thermal contact with the transmission fluid and the heating element is powered by the electric current produced by the thermoelectric generator.

Abstract: A valve with supplemental media and a piston configured to open the valve when a first force is greater than a second force. The pressure of the supplemental media exerts a substantial portion of the first force. The valve also has a biasing member that changes volume as temperature changes and exerts a substantial portion of the second force. The second force decreases as the temperature of the biasing member increases.

Abstract: A differential case has no hole other than two oil holes except for a pinion shaft hole and a pair of drive shaft holes and has an annular receiver attached thereto that has an inner periphery smaller than the outer periphery of side gear washers with respect to the rotation center of the rotation axis of drive shafts and that has an outer periphery located beyond the outermost edge of the oil holes with respect to the rotation center of the rotation axis. This controls the outflow of lubricating oil located radially outward of the inner periphery of the receiver, thus allowing the side gear washers to be supplied with lubricating oil, regardless of whether the differential case is rotating or stops rotating.

Abstract: An object of the present invention is to provide a chain drive system that can reduce sliding resistance between a chain and a guide shoe, minimize increase of sliding resistance over time, and reduce production cost. Provided is a chain drive system 100 including a plurality of sprockets 101 and 102 over which a chain 130 passes over, and one or more guides 110 and 120 that guide the chain 130. The guides 110 and 120 include integral or separate guide shoes 111 and 121 each having a chain running surface. The chain running surfaces include, in part thereof, a lubricated area 114 where a solid lubricant P is held.

Abstract: In one general aspect, the present disclosure is related to a sensor device for detecting selector lever positions of a selector lever for a motor vehicle. The sensor device may include at least four sensors and a code carrier, where the code carrier is arranged such that it is faced by the at least four sensors. The code carrier may be movable with respect to the at least four sensors. The code carrier may be attached to the selector lever. The code carrier may include several coding areas each with an encoding. The code carrier can thus be referred to as coding carrier. The encoding of the individual coding areas can be read by using the sensors.

Abstract: The rotating operation input device has the structure in which the click section applies a clicking force to the shaft at a predetermined rotation angle, and the first controller controls the actuator, based on the control signal received from the second controller, so as to apply a desired external force to the shaft. A shifting operation device is structured by connecting the rotating operation input device to the second controller for controlling the shifting device.

Abstract: A gear-lever mechanism using meshing and pushing for rotation includes a shell; an input device including a driving gear; an output device including a supporting frame and a driven gear set; and a positioning device including a fixed bearing gear. The driven gear set includes a transfer-layer gear and at least one idler gear. The supporting shaft center of each transmission gear in the driven gear set is the sub-bearing point, with each transmission gear meshed with its adjacent drive gears to form two meshing points. The bearing point and the two meshing points form a triangular pushing area. At least two triangular pushing areas in head-to-tail connection form a meshing-pushing-lever-type torsion-output path curved from the driving gear to the fixed bearing gear for connecting and driving, to cause the gear set to rotate with a raising speed, and then reduce the speed and increase the torque.

Abstract: The actuation unit comprises a primary motor and a transmission mechanism for transmitting to a control member the motion generated by the primary motor.

Abstract: A control device is provided for a motor vehicle having an electronically controllable automatic transmission, an electronic transmission selector lever and an electronic control unit. The control unit, which may be the transmission control unit, has a car wash functional module such that, after activation of the car wash functional module, the following steps are permitted at least once and/or at least for a predefined limited time, in each case without activation of the brake pedal: shutting down of the engine in the transmission selector lever position “N”; a subsequent restart of the engine in the transmission selector lever position “N”; and a changeover from the transmission selector lever position “N” to “D”. The car wash functional module can be activated or deactivated by the driver at his discretion via a display operator control element.

Abstract: Disclosed are hollow pistons made from a single piece of starting material and methods of manufacturing hollow pistons from the single piece of starting material.

Abstract: A side rail (1) in a sprit ring shape is to be mounted on a space expander (2) and to constitute, together with the space expander (2), a multi-piece oil ring (3) used in an internal combustion engine. The side rail (1) includes an outer peripheral surface (14) facing radially outward, an inner peripheral surface (13) facing radially inward, a first axial surface (11) facing one end of an axial direction, and a second axial surface (12) facing the other end of the axial direction and parallel to the first axial surface (11). A bevelled portion (30) is provided between the outer peripheral surface (14) and the second axial surface (12) and formed in a tapered surface having a diameter gradually decreasing from a position on the outer peripheral surface (14) at 0.05 mm or more from the first axial surface (11) toward the second axial surface (12).

Abstract: Provided is an oil ring (13) for a piston assembly that can minimize the frictional resistance without impairing the oil control function such as the scraping of lubricating oil from the cylinder wall surface by the oil ring. The oil ring consists of an upper side rail (16), a lower side rail (17) and an annular expander (18) interposed between the two side rails, and is received in an oil ring groove (8) with a prescribed vertical clearance (20) that permits tilting of the side rails. An outer peripheral surface (16E, 17E) of each side rail is provided with a radially inward slant. Therefore, during the upward stroke of the piston, the upper side rail tilts in the radially outward direction so that the effective slant angle of the outer peripheral surface of the upper side ring is adjusted to an optimum value.

Abstract: A sealing device provides sealing so as to prevent a sealed fluid in a machine inner side from leaking to a machine outer side between a housing and a rotating shaft which is inserted to a shaft hole provided in the housing. The sealing device has a seal flange which is installed to an outer periphery of the rotating shaft, and a seal lip which is installed to an inner periphery of the shaft hole of the housing and slidably comes into contact with the seal flange over an entire periphery. The sealing device includes a thread groove which exerts a fluid pumping action when the rotating shaft rotates. The thread groove is provided at a position which does not intersect a contact area where the seal lip slidably comes into contact with the seal flange over the entire periphery, thereby suppressing generation of static leakage.

Abstract: A sealing device provides sealing so as to prevent a sealed fluid in a machine inner side from leaking to a machine outer side between a housing and a rotating shaft which is inserted to a shaft hole provided in the housing. The sealing device has a seal flange which is installed to an outer periphery of the rotating shaft, and a seal lip which is installed to an inner periphery of the shaft hole of the housing and slidably comes into contact with the seal flange over an entire periphery. The sealing device includes a thread groove which exerts a fluid pumping action when the rotating shaft rotates. The thread groove is provided at a position which does not intersect a contact area where the seal lip slidably comes into contact with the seal flange over the entire periphery, thereby suppressing generation of static leakage.

Abstract: A mechanical seal device for use in a water environment includes: a stationary sealing ring made of SiC; and a rotating sealing ring made of SiC and arranged opposite to the stationary sealing ring, the mechanical seal device bringing opposite sliding surfaces of the stationary sealing ring and the rotating sealing ring into close contact with each other to seal a sealed fluid, wherein at least one of the sealing rings including the sliding surfaces is configured by a sintered compact of a material including SiC as a base material compounded with an Al additive, and a specific resistance value of the sealing ring configured by the sintered compact including the sliding surface is equal to or lower than 100 ?·cm.

Abstract: A method and system for actively controlling an axial separation between a seal face of a stationary ring and a seal face of a rotating ring of a gas seal is disclosed. At least one property is sensed indicative of a condition of at least one of the seal faces. With at least one sensing device, a characteristic of the axial separation between the seal faces is sensed. A net magnetic force of at least one magnetic device is adjusted based on the property and/or the characteristic. Adjusting the net magnetic force adjusts the axial separation between the seal faces. Without using a buffer gas between the seal faces, flow of gas or other fluid is controlled between the seal faces by adjusting the axial separation.

Abstract: There is provided a valve assembly that includes a retaining ring disposed within a cavity formed by adjoining a retainer and a disk member. The retaining ring can be disposed at a slant with respect to an inner surface of the cavity.

Abstract: A butterfly valve for controlling gas flow is disclosed. The butterfly valve may include a valve body, the valve body defining a bore and a shaft configured for rotatable motion with respect to the valve body and including a shoulder. The butterfly valve may further include a disk housed within the bore, operatively coupled with the shaft, and configured to control gas flow through the bore based on a rotational position of the shaft relative to the valve body. The butterfly valve may further include a ball bearing operatively coupled with the shaft and including a ball and a race. The butterfly may further includes a spring configured to provide an axial force on the shaft, the axial force configured to press the shoulder of the shaft against the race of the ball bearing to prevent an outer edge of the disk from contacting an inner wall of the bore.

Abstract: A system includes a ball valve. The ball valve includes a housing, a ball, and a first valve seat assembly. The housing includes a chamber, a first fluid passage intersecting the chamber, and a second fluid passage intersecting the chamber. The ball is disposed in the chamber and is configured to control fluid flow between the first and second fluid passages. The first valve seat assembly is disposed between the ball and the housing. The first valve seat assembly includes a first seat configured to seat against the ball both above and below a pressure threshold, and a second seat configured to seat against the ball only above the pressure threshold, wherein the second seat has a coefficient of friction that is lower than the first seat.

Abstract: The invention relates to a sanitary change-over valve (1) having a valve housing (2) which has one valve inlet (3) and two selectively actuatable valve outlets (4, 5), having a valve piston (6) which is movable from a first switch-over position in which the fluid is guided by way of a flow path that is routed through a first valve outlet (4) to a second switch-over position in which the fluid is guided by way of a flow path that is routed by way of a second valve outlet (5) as soon as that portion of the second flow path that is routed beyond the change-over valve (1) has been released, wherein the valve piston (6) is configured as a hollow body through which the fluid in the course of at least one of the flow paths is routed by way of at least one piston inlet (9) that is disposed on the piston circumference.

Abstract: An apparatus to allow or stop an air flow into an enclosed environment or piping system comprises (a) a housing, (b) a first valve seat, (c) a first sealing member, (d) a second valve seat, (e) a second sealing member, (f) at least one locking mechanism configured to limit a movement of the first sealing member and/or the second sealing member; wherein the first sealing member moves away from the first valve seat when the second pressure is greater than the first pressure in a predetermined pressure difference; wherein the second sealing member moves away from the first valve seat when the third pressure is greater than the second pressure in a predetermined pressure difference; wherein the first pressure communicates with a system pressure in the piping system; and wherein the third pressure communicates with an ambient air pressure.

Abstract: A snap-action valve assembly includes a valve flap positioned within a conduit for controlling exhaust flow through the conduit. A shaft supports the valve flap in the conduit for rotation about a pivot axis between a closed position and an open position. A guide is fixed to the valve flap. A torsion spring is positioned at least partially outside the conduit and includes a first end restricted from rotation in at least one direction. The torsion spring includes a second end coupled to the guide. The torsion spring is preloaded to urge the valve flap into contact with an inner surface of the conduit when the valve flap is in the closed position.

Abstract: A snap-action valve assembly for an exhaust system includes a valve flap positioned within a conduit. A shaft supports the valve flap in the conduit for rotation about a pivot axis between a closed position and an open position. A roller is supported for rotation on a post. The post is fixed to the shaft by a lever arm. A torsion spring includes a first end coupled to the conduit and a second end coupled to the roller. The torsion spring is preloaded to urge the valve flap into contact with an inner surface of the conduit when the valve flap is in the closed position. A method of assembling the snap-action valve assembly with a predetermined spring preload torque is also discussed.

Abstract: An air admittance valve preventing mephitis overflow, having a main body with an air entry guide base defining an air entry guide; a pivot support; and a valve seat. A sealing valve group having a sealing valve body that defines a recess; a flexible member; a pivot housing; and a pivot. The valve seat is located about the air entry guide. The pivot is located in the pivot housing and the pivot support, and the pivot is located along, or adjacent to, the center of gravity of the sealing valve body. The flexible member is at least partially located in the recess and abuts the main body; and when the air admittance valve is closed, the sealing valve body abuts the valve seat.