Abstract: A hydrodynamic coupling device for producing a torque transmission connection between a drive unit and a transmission is provided including a first coupling device attached to the drive unit for coupling the hydrodynamic coupling device with the drive unit for transmitting a torque between the hydrodynamic coupling device and the drive unit and a second coupling device attached to the transmission for coupling the hydrodynamic coupling device with the transmission for transmitting a driving and/or braking torque between the hydrodynamic coupling device and the transmission. A method of making a hydrodynamic coupling device is also provided.

Abstract: A method of connecting a starter ring gear connected with a converter cover, and a torque converter including a starter ring gear connected with a converter cover by the method. The method includes setting the starter ring gear at a corner portion of the converter cover in alignment with each other, and producing a plastic flow of metal at the corner portion thereof, the plastic flow of metal forming an engaging member disposed on an outer circumferential surface of a cylindrical wall of the converter cover and engaged with an engaging member disposed on an inner circumferential surface of the starter ring gear, to thereby connect the starter ring gear with the converter cover. The starter ring gear and the converter cover are rotatable about a rotation axis. The corner portion of the converter cover is formed between the cylindrical wall and a disk wall connected therewith.

Abstract: A hydrodynamic clutch device, especially a hydrodynamic torque converter, includes a pump impeller installed in a housing, a turbine impeller having a turbine shell connected nonrotatably to a turbine hub, and possibly a stator. The turbine hub consists of several individually manufactured parts such as a sheet-metal parts, and the turbine shell is designed and mounted on the turbine hub so that it assumes some of the functions of the turbine hub, such as the sealing and guide functions.

Abstract: The invention relates to a hydrodynamic converter comprising a torus-shaped working chamber surrounding the converter axis, said chamber having the form of a ring channel in an axial cross-section; an impeller which is rotationally fixed to an input shaft; a turbine wheel which is rotationally fixed to an output shaft; and a ring of adjustable vanes. The converter is designed in such a way that it has a lambda value of less than 0.0005.

Abstract: A constant velocity transmission which provides maximum torque and speed from a power source such as an internal combustion engine to and output shaft of the transmission while maintaining the engine at optimum operational speed. The transmission takes advantage of the principle of fluid friction to transmit rotational forces from drive blades mounted on an input shaft to stater blades positioned on the inside of a drum encompassing one end of the input shaft and the drive blades. The drive blades slidably mounted on a slanted surface of a drive drum on the input shaft and move closer to and away from the stater blades when laterally translated. Fluid driven by the drive blades imparts varied force and torque to the stater blades depending on their distance therefrom thereby transmitting variable speed and torque to the output shaft attached to the drum.

Abstract: A torque converter comprises an impeller shell, a pump impeller integrally formed with the impeller shell, a turbine runner, a stator, a front cover, and at least one of a flanged portion through which a driving power of an engine is transmitted and a ring gear for a starter. The flanged portion is formed on an outer peripheral portion of an outer hull that includes the impeller shell and the front cover. A pilot boss portion is disposed at an axial portion of the front cover and is adapted to be fitted to a crank shaft of the engine, and a sleeve-like oil pump driving shaft is disposed at an axial portion of the impeller shell and is adapted to drive an oil pump. The pilot boss portion is formed integrally with the front cover through a plastic working operation, and the flanged portion formed at a front portion of the outer periphery of the front cover is increased in thickness through a plastic working operation that forms the flanged portion as a lamination.

Abstract: A torque converter comprises an impeller shell, a pump impeller integrally formed with the impeller shell, a turbine runner, a stator, a front cover, and at least one of a flanged portion through which a driving power of an engine is transmitted and a ring gear for a starter. The flanged portion is formed on an outer peripheral portion of an outer hull that includes the impeller shell and the front cover. A pilot boss portion is disposed at an axial portion of the front cover and is adapted to be fitted to a crank shaft of the engine, and a sleeve-like oil pump driving shaft is disposed at an axial portion of the impeller shell and is adapted to drive an oil pump. The pilot boss portion is formed integrally with the front cover through a plastic working operation, and the flanged portion formed at a front portion of the outer periphery of the front cover is increased in thickness through a plastic working operation that forms the flanged portion as a lamination.

Abstract: The present invention provides a torque converter support for an automatic transmission which uses a driving gear of a fluid pump to support the torque converter. The driving gear is supported by a journal area of the fluid pump. The torque converter impeller hub, attached to the torque converter, is engaging the driving gear and has at least one rib therearound. A hollow bore of the driven gear rides against the rib, offering structural support to the torque converter impeller hub and torque converter. The driven gear also has a hub. The hub has an outer surface which rides against the journal area and provides the base support for the system.

Abstract: In a fluid coupling with a baffle plate protruding on the side of an inner peripheral surface of a circulating circuit, a clutch chamber is defined between a back of a turbine impeller and a side cover covering the back of the impeller, to communicate with an outer periphery of the circulating circuit. The clutch chamber is divided by a clutch piston into an inner chamber portion on the side of the turbine impeller and an outer chamber portion on the side of the side cover. The clutch piston is axially movably connected to the turbine impeller, thereby constituting a lock-up clutch, so that a first oil passage leading to the outer chamber portion and a second oil passage leading to an inner periphery of the circulating circuit are put into alternate communication with a discharge portion of an oil pump and with an oil reservoir in a switched manner.

Abstract: A fluid coupling comprising a pump including a pump shell having an annular core ring, and a plurality of impellers disposed in the pump shell; and a turbine including a turbine shell disposed opposite the pump and having an annular core ring, and a plurality of runners disposed in the turbine shell, wherein an annular baffle plate is mounted on an inner or outer periphery of the core ring of the pump shell or the core ring of the turbine.

Abstract: A hydrodynamic clutch device, especially a hydrodynamic torque converter, includes a pump impeller installed in a housing, a turbine impeller having a turbine shell connected nonrotatably to a turbine hub, and possibly a stator. The turbine hub consists of several individually manufactured parts such as a sheet-metal parts, and the turbine shell is designed and mounted on the turbine hub so that it assumes some of the functions of the turbine hub, such as the sealing and guide functions.

Abstract: A hydrodynamic torque converter a hydrodynamic circuit has at least a pump impeller and a turbine wheel. The turbine wheel has a turbine shell with a blading and a turbine hub which is in rotary connection with an output shaft. The turbine shell extends radially inward between an extension region of axial abutments and is provided with stiffeners.

Abstract: A stepless continuously variable transmission system has a casing with inlet (or outlet) holes, the casing housing an inlet and output shaft which are connected by series of concentric cages, alternate cages being connected to the inlet and outlet shafts alternately whilst remaining free to rotate on the other shaft respectively. The cages include series of blades which interact with a transmission medium which is moved in a direction or directions in the casing between inlet and outlet so that the blades experience changes in angular momentum of the transmission medium, the blades being curbed oppositely in relation to whether their cage is an inlet or outlet connected cage.

Abstract: The present invention provides a fluid pump for an automatic transmission which has at least one driven gear which has a hub portion insertable into the housing of the pump. By using this apparatus, the driven gear needs only to be aligned in one portion of the pump housing. This eliminates the need to align bores in both halves of the pump housing and to align the post section of the driven gears with the bores in the pump housing.

Abstract: A seal structure has a seal lip and a splash lip. The splash lip is disposed to contact a rotating shaft at an axial location intermediate the seal lip and a support bushing to prevent a high velocity oil stream, departing between the bushing and the shaft, from impinging the seal lip prior the velocity of the oil stream being reduced.

Abstract: A torque converter has a lip seal abutting the torque converter impeller control pump drive hub. The drive hub is rotatably supported in a transmission housing. Oil from the drive hub side of the bushing passes through the bushing into a chamber sealed from atmosphere by the lip seal. The lip seal has a component rotatably sealing on a diameter greater than the drive hub diameter. The bushing, in one embodiment, has a control passage for exhausting a portion of the oil from the control pump side prior to reaching the chamber.

Abstract: A flange portion formed on an inner periphery of a flywheel is fitted to an end of a crankshaft. A spline piece is fitted to an inner peripheral surface of the flywheel. The flange portion of the flywheel and a flange portion of the spline piece are commonly fastened to the end of the crankshaft by bolts. An upper end of a driving shaft is spline-fitted at a point into a driving shaft coupled portion of the spline piece which is accommodated in an internal hole in the crankshaft. Thus, in coaxially coupling the flywheel and the driving shaft to the end of the crankshaft, it is possible to make such a coupled area compact and to reduce vibration by an accurate centering thereof.

Abstract: A power transmission unit with at least one driving shaft that can be coupled to a driven machine includes a modular hydrodynamic coupling unit. The coupling unit includes at least two blade wheels, which together form at least one toroidal working chamber. The two blade wheels each can be connected non-rotatingly to a hub-like element, which can be connected non-rotatingly with one of the driving shaft or driven shaft. An intermediate hub is disposed between at least one blade wheel and a corresponding hub-like element. The intermediate hub is coupled non-rotatingly to the blade wheel and extends in the axial direction from the blade wheel at least to directly above an axial end wall of the housing of the coupling unit. The intermediate hub is removably securable to the coupling housing. The hub-like element forms at least one axial stop for the intermediate hub when it is mounted in the housing.

Abstract: A fluid coupling includes an input shaft having a speed-increasing gear train, an impeller operatively connected to the input shaft, an impeller casing fixed to the impeller, and an output shaft having a runner operatively combined with the impeller. The impeller, the runner and the impeller casing jointly define a working fluid chamber. The impeller casing and the impeller are made of a material having a small specific gravity and a high allowable stress range for reducing centrifugal stresses developed therein when the impeller casing rotates at high speeds. The material may be a titanium alloy or an aluminum alloy.

Abstract: A flange portion formed on an inner periphery of a flywheel is facet-fitted to an end of a crankshaft. A spline piece is facet-fitted to an inner peripheral surface of the flywheel. The flange portion of the flywheel and a flange portion of the spline piece are commonly fastened to the end of the crankshaft by bolts. An upper end of a driving shaft is spline-fitted at a point into a driving shaft coupled portion of the spline piece which is accommodated in an internal hole in the crankshaft. Thus, in coaxially coupling the flywheel and the driving shaft to the end of the crankshaft, it is possible to make such a coupled area compact and to reduce vibration by an accurate centering thereof.

Abstract: A flange portion formed on an inner periphery of a flywheel is fitted to an end of a crankshaft. A spline piece is fitted to an inner peripheral surface of the flywheel. The flange portion of the flywheel and a flange portion of the spline piece are commonly fastened to the end of the crankshaft by bolts. An upper end of a driving shaft is spline-fitted at a point into a driving shaft coupled portion of the spline piece which is accommodated in an internal hole in the crankshaft. Thus, in coaxially coupling the flywheel and the driving shaft to the end of the crankshaft, it is possible to make such a coupled area compact and to reduce vibration by an accurate centering thereof.

Abstract: An impeller shell 40a of a torque converter includes a main portion 41, a connection portion 42 and a stepped portion 43. The main portion 41 has a curved inner peripheral surface 41a carrying impeller blades, and is opposed to a turbine 5. The connection portion 42 has a cylindrical form larger in diameter than an outer periphery of the inner peripheral surface 41a, and is fixed to a front cover 3. The stepped portion 43 couples an end of the main portion 41 near an engine to an end of the connection portion 42 near a transmission. A corner portion formed of the inner peripheral surface 41a and a surface 43a near the engine has a radius set to 4 mm or less by preliminary forming by a press and subsequent finish forming by a press.

Abstract: A sleeve having a wear resistant surface is fitted over and secured to the outer surface of a hub for a bladed torque converter wheel. The sleeve may be secured by mechanical interference, bonding, or welding. The sleeve is adapted for use in transmissions for front-wheel drive and rear-wheel drive vehicles and is suitably formed for engagement with various drive connections.

Abstract: An automatic transmission, in particular an infinitely variable automatic transmission for motor vehicles, contains a radial piston pump (1) for supplying a hydrodynamic converter (3), a lubricating device and control and actuating devices of the automatic transmission via a number of control conduits. Radially outside of its outlet valves, the radial piston pump (1) contains an annular chamber (22), which extends around the radial piston pump (1). The annular chamber (22) is embodied as a damping chamber and is mainly arranged in a recess (23) of the converter housing (2), and therefore almost completely outside of the pump housing (17). The annular chamber (22) is bordered by the recess (23) of the converter housing (2), the pump housing (17) and/or a separate pump cover (24). The annular chamber (22) is not symmetric and with its volume extends into the adjoining free spaces of the automatic transmission.

Abstract: A flange portion formed on an inner periphery of a flywheel is facet-fitted to an end of a crankshaft. A spline piece is facet-fitted to an inner peripheral surface of the flywheel. The flange portion of the flywheel and a flange portion of the spline piece are commonly fastened to the end of the crankshaft by bolts. An upper end of a driving shaft is spline-fitted at a point into a driving shaft coupled portion of the spline piece which is accommodated in an internal hole in the crankshaft. Thus, in coaxially coupling the flywheel and the driving shaft to the end of the crankshaft, it is possible to make such a coupled area compact and to reduce vibration by an accurate centering thereof.

Abstract: A hydraulic power transmission, such as a torque converter, has a pump impeller and a turbine runner with inclined blades having edge portions bent to form right angle connections to shells and cores of the pump impeller and the turbine runner. The inclination of the blades relative to the shells and cores provide improved transmission performance while the bent connecting edges forming right angles with the shells and cores eliminate gaps and secondary flows from acute angles between between the blades and the shells and cores to reduce oil leakage and the occurrence of secondary flows caused by such gaps. These blades have ample strength without central strengthening ribs to eliminate secondary flows caused by such ribs.

Abstract: A rotating pump seal is interposed between a transmission's pump and pump body bushing. The seal includes a predetermined flow area allowing a sufficient amount of fluid flow to lubricate the bushing while restricting excessive flow.

Abstract: A hydrokinetic torque converter which includes pump wheels and/or turbine wheels in particular of a Fottinger coupling, wherein all the required blades are stamped in the form of blade blanks, out of a round stamping blank in a single operating process, in such a manner that each blade blank remains connected, by means of a connecting web, to a ring-shaped area of the stamping blank which remains intact during the stamping. The blade blanks are then subjected to a shaping process, in which they are reshaped into the final three-dimensional shape of the blade, whereby the connection with the ring-shaped area remains intact, and, in a shaping process, the ring-shaped area is adapted to the contour of the housing that delimits the pump wheel or turbine wheel. A blade carrier is thereby produced which makes it possible to install all the blades, in their three-dimensional position with respect to the pump or turbine wheel, in a single process.

Abstract: Hydrokinetic torque converter, including a housing driven by an internal combustion engine with a housing wall near the drive which is provided with a concentric guide hub, a pump wheel integrated into the housing wall away from the drive, a turbine wheel located between the pump wheel and the housing wall near the drive, which turbine wheel is non-rotationally connected by means of a turbine wheel hub to the output, possibly a stator located between the two, whereby the turbine wheel and/or the pump wheel are provided with axial bearings opposite the stator, and whereby the walls of the pump wheel and/or of the turbine wheel pressurized with axial pressure are provided on their radially inside diameter with mountings for fastening the axial bearings.

Abstract: A three element, three phase hydrodynamic torque converter having improved structural and hydrodynamic characteristics, and automatic transmissions that use a plurality of such hydrodynamic torque converters as replacements for multiple disc wet clutches or the like to effect transmission ratio changes. The hydrodynamic torque converters use a centrifugal impeller and a centrifugal turbine on the forward axial side of the torque converter, and a centripetal stator mounted to the converter shell on the rearward axial side. Three phase operation results when using the specified geometries: [1] torque multiplication, where the speed ratio i=n.sub.t /n.sub.p is greater than one; [2] coupling phase, where the speed ratio approaches one; [3] extension phase, where the speed ratio equals one and then exceeds one. For operation with speed ratio i=n.sub.t /n.sub.p in the range 0.6 .ltoreq.i .ltoreq.1.3, operational efficiency .eta. is found to be between 82 and 88 percent.

Abstract: A fluid drive system in which a forged alloy steel impeller rotated by an input shaft at a constant speed drives a runner through a fluidic coupling, wherein selectively variable differential speed between the impeller and runner is produced by varying the amount of oil between the impeller and runner, wherein both the impeller and runner have radially extending vanes between them defining pockets between them with a bottom surface, the impeller is provided with reinforcing elements integral with the vanes, each reinforcing element spanning a pocket and being clear of the bottom surface. The runner can also be provided with such elements. In any case, the vanes and reinforcing elements are machined from a forged alloy steel billet, by a multi-axis Computer Numerical Controlled (CNC) milling machine under three-dimensional control with specialized tooling.

Abstract: A fixed fluid capacity fluid coupling comprises a main bypass chamber and an auxiliary bypass chamber. The output wheel includes at least one hole and an offtake channel connecting the working circuit to the auxiliary bypass chamber uses this hole. Applications include fixed fluid capacity fluid couplings for driving high-inertia loads.

Abstract: A torque convertor having a tubular toroidal member constituted by a pump, a turbine and a stator is so dimensioned that sufficient room is provided to accommodate associated components without sacrificing performance standards. In particular, since the cross sectional area of the flow passage of the stator, wherein eddies tend to generate and power transmission loss due to fluid collision increases, is larger in proportions to the cross sectional area of either the pump or the turbine the fluid turbulence is reduced.

Abstract: A sealing device has a torque converter housing, a transmission case, an oil pump disposed between the torque converter housing and the transmission case, an oil sealing member disposed between the oil pump and the pump impeller of the torque converter, and seal ring disposed between the oil pump and the torque converter. The oil pump has a protrution extending to the torque converter. The sealing member is disposed between the outer periphery of the protrusion and a flange of the torque converter housing. The seal ring is disposed between the protrusion and the pump impeller hub.

Abstract: A method for forming a torque converter flow path defined by an impeller, a turbine and a stator comprising initiating a meanline design path having an outer radius R1 and an inner radius R2 connected by a tangent line, wherein the outer radius is initially set equal to maximum meanline design offset so as to extend to a meanline design path point at a radius R3 equalling .sqroot.(R8).sup.2 -A/2.pi., and the inner radius is set equal to the outer radius so as to extend to a meanline design path point at R4 equaling .sqroot.(R7).sup.2 +A/2.pi., wherein (R8) and (R7) are the maximum and minimum radial distances, respectively, from the flow path to the torque axis.

Abstract: A securing structure and method of a blade for torque converter for use mainly in industrial construction vehicles to provide its rigid and easy-to-manufacture construction. The structure includes plural circular blades which are secured to a concave surface of a shell with some space in the circumferential direction, a core ring which extends along the circumferential direction of the shell and is secured to concave peripheries of the blades. A tab fitting in slot of the shell is formed integrally on the convex periphery of the blade. A tab fitting in a slot of the core ring is formed integrally on the concave periphery of the blade. Ribs extending in the circumferential direction of the shell are only formed on both ends of the convex periphery and concave periphery of the blade. The convex periphery and the concave periphery are brazed to the shell and the core ring respectively.

Abstract: A mechanization of a vehicular starter/generator machine having minimal impact on the vehicle powertrain. The powertrain includes an engine connected to drive the vehicle through a fluid torque converter and a power transmission. The rotor of the starter/generator machine is formed on the outer circumference of an input shell of the torque converter, and the stator of the machine is formed on the inner circumference of the torque converter housing. This mechanization affords the use of a relatively high capacity machine without appreciably affecting the powertrain packaging.

Abstract: A method of securing a blade to a torque converter for use mainly in industrial construction vehicles provides a rigid and easy-to-manufacture construction. The structure includes plural circular blades which are secured to a concave surface of a shell with some space in the circumferential direction, and a core ring which extends along the circumferential direction of the shell and is secured to concave peripheries of the blades. A tab fitting in a slot of the shell is formed integrally on the convex periphery of the blade. A tab fitting in a slot of the core ring is formed integrally on the concave periphery of the blade. Ribs extending in the circumferential direction of the shell are only formed on both ends of the convex periphery and concave periphery of the blade. The convex periphery and the concave periphery are brazed to the shell and the core ring respectively.

Abstract: A method for forming a torque converter flow path defined by an impeller, a turbine and a stator comprising initiating a meanline design path having an outer radius R1 and an inner radius R2 connected by a tangent line, wherein the outer radius is initially set equal to maximum meanline design offset so as to extend to a meanline design path point at a radius R3 equalling .sqroot.(R8).sup.2 -A/2.pi., and the inner radius is set equal to the outer radius so as to extend to a meanline design path point at R4 equaling .sqroot.(R7).sup.2 +A/2.pi., wherein (R8) and (R7) are the maximum and minimum radial distances, respectively, from the flow path to the torus axis.

Abstract: A novel torque converter is disclosed which utilizes streamwise vorticity as well as a mean flow within the passageways of the machine to transfer energy efficiency over an extended utility ratio. This is accomplished with novel blade structures utilizing salient edges disposed in part along the mean flow path. Pairs of counter rotating vortices are produced by the impeller blades. The direction of rotation of these vortices is reversed by the turbine blades, efficiently transferring torque from the impeller to the turbine. At speed ratio zero the directions of rotation of the vortices leaving the turbine are again reversed by the stator to impart torque to the stator. This continues until the design speed ratio is achieved. Thereafter, the vortices are guided by the stator passages to the impeller. Below the design speed ratio, the impeller guides the vortices through it to the turbine where their flow is reversed. Above the design speed, the vortices from the stator are reversed by the impeller.

Abstract: An axially toothed gear mechanism for transmitting torque and angular displacement from a driving member to a driven member which can accommodate a slight angular mismatch between the two, and which minimizes backlash and wear of the teeth.

Abstract: A hydrodynamic retarder with a stator blade wheel and a rotor blade wheel whose blades together fill the work chamber for working liquid. Slot shaped inlet openings permit entrance of working liquid to the working chamber. The inlet openings are located at the radially inner region of the rotor blade wheel toward the retarder shaft. Slot shaped outlet openings permit outlet of working fluid. The outlet openings are at the radially outer region of the rotor blade wheel. The slots are oriented to follow the incline of the blades of the rotor blade wheel. The inlet slots each trail a respective rotor wheel blade while the outlet slots each lead that blade in the movement direction of the rotor blade wheel. Particular thicknesses of blades and particular angular sizes of the inlet and the outlet slot openings are disclosed.

Abstract: The present invention relates to a thrust force reduction device for torque converter comprising a pump rotor, a turbine rotor connected to a turbine shaft and disposed opposed to the pump rotor and at least one stator rotor and a fixed cylindrical shaft fitted to a boss of the pump rotor; characterized by that a seal element is fixed to the turbine shaft and produces a thrust reactional force so as to cancel a thrust force which occurs in the torque converter; the seal element facing a fluid chamber receiving pressurized hydraulic fluid exhausted from the turbine rotor, and the seal element being disposed liquid tight between the turbine shaft and a power input guide to the turbine from the engine, to which the turbine is connected.

Abstract: An external shell of a pump wheel of a hydrodynamic flow unit manufactured from a sheet metal pressed part has, in its outlet-side region, an integral connecting sleeve with a cylindrical centering surface and a centered fastening surface extending thereform, and wherein the connecting sleeve is formed by upsettingly deforming, with the fastening surface being given a cylindrical shape and the centering surface being machined to its required diameter after upsettingly deforming.

Abstract: A hydraulic coupling is provided which has a primary blade wheel and a secondary blade wheel confining an operating space, said primary wheel having a first delay chamber connected by channels with the operating space located relatively close to the coupling axis and a second delay chamber, predominantly located further away from the coupling axis than the radially outer limitation of the operating space, the second delay chamber being connected with the operating space by large diameter ports, preferably by the radially outer annular gap between the blade wheels.

Abstract: In a spoked drive wheel for a hydrodynamic torque converter operating with power splitting, having a spoke for connecting a wheel hub to an external ring of the spoked drive wheel, the spoke cross-section is designed in the shape of a wing profile extending along a profile main axis. The profile main axis is transverse to the axis of rotation of the wheel. In this way, the deterioration in the characteristics of the torque converter is kept as small as possible in both power splitting operation and in operation without power splitting.

Abstract: A drive strap utilized for a torque converter of an automotive vehicle accommodating minor misalignment but providing effective transmission of torque. The strap assembly includes thin, flexible straps and very stiff back-stops adjacent one end of each strap to provide a characteristic of increasing axial stiffness as strap deflection increases.

Abstract: A hydraulic torque converter comprising an impeller integral with an input shaft and a rotor which is integral with an output shaft and opposed to said impeller so that a given clearance is formed therebetween, notches which are formed at one circumferential end of the inner periphery of vanes defining outlets of oil passages of the impeller, and notches at circumferential ends of the inner and outer peripheries of the rotor vanes defining inlets of oil passages of the rotor.

Abstract: The fluid friction coupling, which is suitable especially for a fan of an internal combustion engine, comprises a buffer chamber (39) which receives a part of the entire quantity of shear fluid contained in the coupling, through an inlet opening (43) placed beneath the shear fluid level (47), when the coupling is not in rotation. The received partial quantity lowers the liquid level in the shear gaps (23). In cold starting therefore the coupling transmits a reduced torque, which by reason of the consequently increased slip increases the pump effect of a pump device (37) and reduces the fan noise. The quantity of shear fluid contained in the buffer chamber (39) is delivered again to the shear fluid cycle of the coupling with time retardation through a constricted opening (45) when the coupling is in operation.

Abstract: A blade fastening structure for a torque converter or a fluid coupling forming a caulking part previously at an inner peripheral portion of an impeller, and fastening an inner peripheral portion of a blade to a shell by caulking the caulking part; in a torque converter or a fluid coupling forming the shell by welding an inner peripheral portion of a shell body having an annular groove of semi-circular section to a hub concentric with an output shaft, and forming the impeller by arranging a semi-elliptic blade between the shell and a core ring.