Did You Know...
...that the inventor of the electric motor was a blacksmith named Thomas Davenport? Described as "a brilliantly unsuccessful inventor", Davenport invented the first rotary electric motor. In 1836 he headed out -- on foot -- from his Vermont home to file a patent application at the Patent Office in Washington, D.C. By the time he got there, he had squandered away his money and couldn't afford the $30 filing fee so he turned around and went home. When he later mailed in his application with money he'd raised, the Patent office was destroyed in a fire. He did finally get credit for his invention on Feb. 5, 1837.
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| Number | Title | Issue Date |
| 7299630 | Positioning and locking mechanisms and articles that employ the same Disclosed herein is a locking mechanism for positioning or locking an article comprising a housing 3; an optional active element 6 in operative communication with a connecting means 22, wherein the active element 6 and the connecting mean... | 11/27/2007 |
| 7243768 | Clutch having a variable viscosity fluid A clutch (A,B) includes a cam (20,70) and a rotor (22,74), both of which revolve around a common axis (X). The cam has a camming surface (30,72) provided with lobes (32), whereas the rotor carries pistons (26,80) which bear against... | 07/17/2007 |
| 5984066 | Automotive transmission A transmission, capable for use in a wide variety of applications, allows continuously variable output/input ratios. In all embodiments, rotational input motion is converted into reciprocal motion of a reciprocating shaft. Resistance to the reciprocal mot... | 11/16/1999 |
| 5495926 | Hydraulic power transmission apparatus A hydraulic power transmission apparatus having improved valving for accurately regulating the flow of hydraulic material between a pair of cylinders in either of two opposite directions. The valve has a circularly cylindrical occluding member disposed in... | 03/05/1996 |
| 5448478 | Torque split control apparatus A torque split control apparatus for use with an automotive vehicle including an engine for producing a drive. The automotive vehicle is supported on a pair of primary drive wheels and a pair of secondary drive wheels. The drive is transmitted from the en... | 09/05/1995 |
| 5396421 | Torque distribution control device A torque distribution control device includes two rotational speed differential responsive type control couplings each having various transfer torque characteristics which differ in the ratio of a transfer torque to a rotational speed differential. The co... | 03/07/1995 |
| 5303797 | Torque distribution control device for four-wheel drive vehicle A torque distribution control device for a four-wheel drive vehicle includes a rotational speed differential responsive type control coupling combined with a front differential of a front wheel drive line. The control coupling has a variable orifice for v... | 04/19/1994 |
| 5211257 | Power transmission apparatus for four-wheel drive vehicle A power transmission apparatus for four-wheel drive vehicle which uses a hydraulic pump to absorb a rotational speed difference caused between front and rear wheels or left side and right side wheels to thereby materialize the four-wheel drive state and w... | 05/18/1993 |
| 5194053 | Rotational speed differential responsive type control coupling with variable transfer torque control means A transfer torque control device for a rotational speed responsive type control coupling is provided for providing a desired variation of a transfer torque in response to a variation of a rotational speed differential. The control coupling has orifices fo... | 03/16/1993 |
| 5162024 | Rotational speed differential responsive type control coupling In a rotational speed differential responsive type control coupling, restrictions of a fixed opening are provided for restricting discharge of oil through discharge passages and thereby producing an oil pressure for urging relative rotatable coupling memb... | 11/10/1992 |
| 5137130 | Controlled type rotation speed difference sensitive coupling A controlled type rotation speed difference sensitive coupling is disclosed, which is for use between first and second rotatable members. The coupling comprises a drive housing connected to the first rotatable member, a rotor connected to the second rotat... | 08/11/1992 |
| 5137129 | Variable speed transmission Utilizing the characteristic that a hydraulic pump, such as a gear pump, having the fluid flow from its outlet restricted will tend from the increasing internal pressure to rotate with the input shaft, a variable speed transmission is designed which inclu... | 08/11/1992 |
| 5117956 | Hydraulic transmission coupling apparatus A hydraulic transmission coupling apparatus for transmitting a driving force to a front wheel driving shaft and a rear wheel driving shaft of a four-wheel drive vehicle, which is provided with a pump to generate hydraulic pressure corresponding to a rotat... | 06/02/1992 |
| 5106347 | Rotational speed differential responsive type torque transmitting assembly with variable orifice means A limited slip differential is disclosed which includes a first rotary element, a second rotary element, and a hydraulic unit including a plurality of reciprocal pistons in slidable engagement with an internal cam surface of the first rotary element. The ... | 04/21/1992 |
| 5074825 | Hydraulic transmission coupling apparatus A hydraulic transmission coupling apparatus which is used instead of a center differential or a viscous coupling being usually mounted between a front wheel drive shaft and a rear wheel drive shaft of a four-wheel drive vehicle, and transmits driving forc... | 12/24/1991 |
| 5024309 | Rotational speed differential responsive type control coupling A rotational speed differential responsive type control coupling is provided with a device for manually or automatically preventing relative rotation of a drive housing and rotor in order to prevent working oil from being heated up to an excessively high ... | 06/18/1991 |
| 4995491 | Power transmission apparatus A power transmission apparatus suitable for use with a four wheel drive apparatus of an automobile which can prevent production of rattling noises of a driving system and occurrence of a swerving phenomenon of the automobile. The apparatus includes a cam ... | 02/26/1991 |
| 4981201 | Variable drive apparatus An infinitely variable high efficiency drive mechanism that can act as a transmission or as a coupling between a prime mover and the reducing gears of a standard or automatic transmission, replacing a clutch or torque converter as a means of power transmi... | 01/01/1991 |
| 4980521 | Power transmission apparatus A power transmission apparatus suitable for use with a four wheel drive apparatus of an automobile which can prevent spouting of working fluid through a sealing portion or the like and introduction of external air into the apparatus through a sealing port... | 12/25/1990 |
| 4958711 | Rotational speed differential responsive type joint A rotational speed differential type torque transmitting assembly includes a rotor rotatably disposed in a drive housing. During rotational speed differential between the rotor and drive housing, hydraulic fluid is discharged out of variable volume chambe... | 09/25/1990 |
| 4957473 | Rotational speed differential responsive type torque transmitting assembly A limited slip differential is disclosed which includes a first rotary element, a second rotary element, and hydraulic means including a plurality of reciprocal pistons in slidable engagement with internal cam surface means of the first rotary element. Th... | 09/18/1990 |
| 4932510 | Vehicle speed responsive variable torque transmitting assembly A torque transmitting assembly comprises a first rotary element including internal cam surfaces, a second rotary element disposed in the first rotary element, the second rotary element including a rotor containing a plurality of radially outwardly opening... | 06/12/1990 |
| 4921085 | Rotational speed differential responsive type joint A torque transmitting assembly in the form of a rotational speed differential responsive type joint is disclosed. It comprises a drive housing as a first rotary member and a rotor as a second rotary member. The second rotary member is disposed in the firs... | 05/01/1990 |
| 4881626 | Power transmission apparatus for vehicle of four-wheel drive type A power transmission apparatus for a four-wheel drive vehicle has a first rotary shaft for transmitting drive force to front wheels of the vehicle, a second rotary shaft for transmitting drive force to rear wheels of the vehicle, and a hydraulic pump conn... | 11/21/1989 |
| 4829769 | Hydraulic transmission coupling apparatus A power transmission apparatus uses a vane pump in which a rotor coupled to a second rotary shaft is rotatably housed in a rotatable housing coupled to a first rotary shaft, and flow of hydraulic operating fluid in the vane pump due to relative rotation o... | 05/16/1989 |
| 4795014 | Power transmission apparatus A transmission wherein power is transmitted between a camshaft and a rotating cylinder block through a pair of pistons reciprocally and slidably disposed within a pair of adjacent cylinders in the cylinder block. In one mode of operation, the transmission... | 01/03/1989 |
| 4597483 | Hydrostatic clutch A hydrostatic clutch, includes coaxial driving and driven rotative members, so that when in the clutched condition rotative power is transferred from the driving to driven member. The clutch includes a plurality of pistons bearing upon an inclined cam, an... | 07/01/1986 |
| 4564095 | Friction-less hydraulic clutch device This clutch device is designed to be friction-less, and it employs hydraulic fluid for the engaging action upon a drive flange, without the use of friction linings. Primarily, it consists of an internal housing, return spring, piston and pushrod, which ar... | 01/14/1986 |
| 4518069 | Adjustable speed drive utilizing radially movable hollow pistons which act on a cam surface An adjustable hydraulic speed drive for controllably maintaining output torque and variable output speed is disclosed. The drive utilizes a rotating group of pistons in radially arranged bores in a portion of an input shaft. A supply of controlled fluid i... | 05/21/1985 |
| 4469012 | Pressurized fluid mechanism comprising reaction rollers mounted on pistons The invention relates to a pressurized fluid mechanism comprising a cam, a cylinder-block mounted for rotation with respect to the cam, cylinders disposed radially in said cylinder-block, pistons sliding in said cylinders, supporting rollers supporting th... | 09/04/1984 |
| 4387795 | Inter-axle transmission apparatus Apparatus selectively providing either two or four wheel drive for a motor vehicle wherein the ratio of torque transmitted to the front wheels when the four wheel drive is selected is preset and wherein limited slippage between the front and rear wheel dr... | 06/14/1983 |
| 4214652 | Variable power transmission and absorption device An apparatus is provided which is adapted to deliver or absorb variable amounts of torque or to deliver variable quantities of an incompressible fluid at a predetermined pressure. The device comprises a positive displacement pump capable of pumping a comp... | 07/29/1980 |
| 4193484 | Rotary hydrostatic coupling A rotary hydraulic coupling wherein the rotary motion of a fluid-filled casing is transmitted to a coaxial driven shaft through the medium of a plurality of pistons which have eccentric drive connections with the driven shaft and which work in cylinders t... | 03/18/1980 |
| 4142617 | Hydrostatic coupling A rotary hydraulic coupling of the type wherein the powered movement of a plurality of reciprocable pistons, which are carried and driven by a drive shaft, work in cylinders which are carried by a driven shaft, and wherein the varying backup pressure of i... | 03/06/1979 |
