2969 results about "Gear ratio" patented technology

A core sampling biopsy device is compatible with use in a Magnetic Resonance Imaging (MRI) environment by being driven by either a pneumatic rotary motor or a piezoelectric drive motor. The core sampling biopsy device obtains a tissue sample, such as a breast tissue biopsy sample, for diagnostic or therapeutic purposes. The biopsy device may include an outer cannula having a distal piercing tip, a cutter lumen, a side tissue port communicating with the cutter lumen, and at least one fluid passageway disposed distally of the side tissue port. The inner cutter may be advanced in the cutter lumen past the side tissue port to sever a tissue sample. A cutter drive assembly maintains a fixed gear ratio relationship between a cutter rotation speed and translation speed of the inner cutter regardless of the density of the tissue encountered to yield consistent sample size.

A tool drive system for transferring rotational power from a rotational tool, such as a drill or ratchet, to at least one input drive shaft which then transfers the power to at least one output drive shaft. The angle of at least one input drive shaft being adjustable relative to at least one output shaft. The tool drive system comprises a round housing with an angle adjuster attached to the input shaft that assists in adjusting and locking the angle of the input shaft relative to the output shaft in an almost circular span. The input and output shafts may be positioned in a user-selected gear ratio from the input to output shafts or vice versa.

A circular saw in which cutting speed of a saw blade is smoothly controlled. A speed change mechanism of a circular saw includes first and second rotating shafts disposed parallel to each other, and first and second gear trains having different gear ratios and each having a combination of a drive gear and a driven gear as one unit which are engaged with each other and transmit torque of the first rotating shaft to the second rotating shaft. A torque transmission path via the first gear train is defined as a first power transmission path and a torque transmission path via the second gear train is defined as a second power transmission path, and the transmission path is switched between the first power transmission path and the second power transmission path.

A method for regulating or controlling the transmission ratio of an automatic power-branched transmission. Power is transmitted through a shaft driven by an engine, a variable speed drive, a gear transmission, a driven shaft, and at least two control clutches. The variable speed drive and the gear transmission are connected to each other in such a way that the regulating range of the variable speed drive is traversed in one direction within a first range of transmission ratios, and is traversed in the opposite direction within a second range of transmission ratios during traversing of the entire range of transmission ratios. The shifting strategies result in reduced wear of the endless belt device and allow for comfortable changing between the transmission ratio ranges.

A multiple speed transmission capable of producing five underdrive gear ratios, one direct drive ratio, four overdrive ratios, and four reverse ratios includes four interconnected planetary gearsets, multi-plate clutches and brakes controlling the gearset elements, and a coupler that changes between forward drive and reverse drive by holding and releasing alternate gearset components against rotation on the transmission case. The transmission in combination with a single-speed transfer case having either an on-demand transfer clutch, or a full-time all-wheel drive system, are formed in an integrated package.

An engine system and method are disclosed for controlling pre-ignition of an alcohol fuel. In one embodiment, the fuel injection timing is adjusted to cause the fuel to avoid combustion chamber surfaces. In another embodiment, the fuel injection timing is adjusted to spray the fuel directly onto the piston surface to cool the piston. Also disclosed is a cylinder cleaning cycle in which engine knock is purposely caused for one to hundreds of engine cycles by adjusting the fuel content away from alcohol toward gasoline. Further measures to cause knock which are disclosed: adjusting spark timing, intake boost, exhaust gas fraction in the cylinder, cam timing, and transmission gear ratio.

An apparatus and method are provided to execute synchronous shifting in a powertrain system having multiple torque-generative devices each operable to independently supply motive torque to the transmission device. The exemplary transmission device comprises a two-mode, compound-split, hybrid electromechanical transmission. Operation includes operating in an initial fixed gear ratio, operating the transmission in a mode operation, and, operating the transmission in a final fixed gear ratio. The control system reduces reactive torque of a clutch activating the initial gear, and deactivates the first torque-transfer device when the reactive torque is less than a predetermined value. It determines that speed of an input shaft to the transmission is substantially synchronized with a rotational speed of the second torque-transfer device, and actuates the second torque-transfer device.

A gear-operated speed change apparatus for an automatic transmission, which can make the degree of freedom for selecting a gear ratio higher than that of the case using the Ravigneaux type composite planetary gear train, while achieving a strength advantage of the gear train, an improvement in the fuel economy, coaxial positioning of the input port and output portions and size reduction of the automatic transmission altogether. The apparatus can achieve at least seven forward speeds and one reverse speed by engaging / releasing four clutches and two brakes. One of the three planetary gear sets can reduce the speed of an input rotation always or increase the input rotation always. One of the remaining two planetary gear sets is a double sun gear type planetary gear set including a third carrier having a center member positioned between two sun gears for inputting or outputting a rotation.

A clutch mechanism is disclosed for use with a hybrid electric vehicle wherein the electric motor-generator and engine are arranged in a series configuration. The clutch mechanism is positioned between and in communication with the electric motor-generator and engine to allow for either direct drive or a predetermined gear ratio between the electric motor-generator and engine. The electric motor-generator is preferably an integrated electric motor and generator. The engine is preferably a combustion engine.

A method of measuring and analyzing vibrations of a mechanical system, e.g., for performing gear and bearing fault detection within a system having a reference shaft and a plurality of rotating components. The method may include the steps of tabulating gear ratios of the plurality of rotating components relative to the reference shaft in integer form, establishing a measurement specification and communicating the measurement specification to a digitizer, recording vibration data from the mechanical system during operation, and resampling the recorded vibration data using the tabulated gear ratios to obtain vibration data corresponding to the rotating components and a vibration signature for a component of interest at predetermined angular increments.

A continuously variable transmission apparatus having input and output shafts, a toroidal-type continuously variable transmission unit (CVT unit), a gear-type differential unit with gears, and a control unit, the CVT unit has; input and output side disks, power rollers, input and output side rotation sensors, wherein the differential unit has; a first input portion and a second input portion, and wherein the control unit regulates the transmission ratio of the CVT unit so as to change relative displacement speeds of the gears of the differential unit to thereby convert the rotational state of the output shaft to forward and backward rotations with a stationary state being interposed therebetween, with the input shaft being kept rotating in one direction, and to calculate a rotational speed of the output shaft based on rotational speeds of the input and output side disks and a gear ratio of the differential unit.

Power roller-side concave grooves are opposed to disk-side concave grooves 19, 19 so as to have angles therebetween in a rolling contact area between a peripheral surface of the power roller and a one-side surface 17 of a disk 16 in an axial direction regardless of a transmission gear ratio of a toroidal continuously variable transmission. Accordingly, the disk-side concave grooves 19, 19 are formed so as to have angles with respect to a circumferential direction of the disk 16 when viewed from a normal direction relative to the one-side surface 17 in the axial direction. Meanwhile, the power roller-side concave grooves are formed into a concentric shape (or a spiral shape) about a central shaft of the power roller. As a result, it is possible to prevent a decrease of a contact area in the rolling contact area regardless of the transmission gear ratio.

A variety of methods and arrangements for controlling the operation of an internal combustion engine in a skip fire variable displacement mode are described. In general, a firing control unit determines working chamber firings during operation of the engine that are suitable for delivering a desired engine output. In one aspect, the firing control unit is arranged to isolate the generation of firing sequences having frequency components in a frequency range of concern and to alter the firing sequence in a manner that reduces the occurrence of frequency components in the frequency range of concern. In another aspect, a filter is arranged to filter a feedback signal to provide a filtered feedback signal that is used in the determination of the working chamber firings. In preferred embodiments, the frequency characteristics of the filter are variable. In various embodiments, the frequency characteristics of the filter vary as a function engine speed and / or a transmission gear ratio.

PCT No. PCT / JP97 / 03887 Sec. 371 Date Jun. 25, 1998 Sec. 102(e) Date Jun. 25, 1998 PCT Filed Oct. 27, 1997 PCT Pub. No. WO98 / 19083 PCT Pub. Date May 7, 1998There is disclosed a vehicle control system that controls an automatic transmission by utilizing road information stored in a navigation system unit. In response to the road information stored in a data memory, the upper-limit of a shiftable gear ratio range is determined, thereby allowing change of the gear ratio only within the restricted range. The actual downshift is carried out in response to initiation of a decelerating operation by the driver, such as release of the accelerator pedal, which prevents unnecessary upshift and provides favorable transmission control in conformity with the driver's intention.

An automatic transmission is capable of obtaining appropriate gear ratios for six forward shifts and one reverse shift. The automatic transmission includes a first planetary gear, a second planetary gear, a planetary gear unit including a third planetary gear, and a fourth planetary gear. Also provided are first, second, third and fourth shaft elements, first and second first clutch elements, first, second, and third brake elements, the first clutch element is capable of selectively interconnecting the input shaft and the fourth shaft element. The second clutch element is capable of selectively interconnecting the input shaft and the carrier of the single planetary gear. The first brake element is capable of selectively fixing the first shaft element. The second brake element is capable of selectively fixing the second shaft element. The third brake element is capable of selectively fixing either the sun gear or the carrier of the double pinion planetary gear.

A multi-speed transmission may include an input member and an output member disposed in a housing. A first planetary gear set, a second planetary gear set, a third planetary gear set, and a fourth planetary gear set may also be disposed in the housing, each planetary gear set including a sun gear, a planet carrier, and a ring gear. Six control elements may be operably coupled to the planetary gear sets and selectively engageable to create a set of different gear ratios between the input member and the output member, the set of different gear ratios including at least nine forward gear ratios and at least two reverse gear ratios.

The present invention is a compound planetary gear system which has a moveable sun gear and a lockable sun gear to change the gear ratio between a high gear ratio and a pseudo 1:1 slipping ratio. The system makes use of a ratchet and pawl mechanism to provide a safety backup for when the lockable sun gear is locked. The invention may be used to move the aircraft from a stationary position, for taxiing, and for pre-rotating the wheels prior to landing.

A powertrain system is provided that includes a prime mover and a change-gear transmission having an input, at least two gear ratios, and an output. The powertrain system also includes a power shunt configured to route power applied to the transmission by one of the input and the output to the other one of the input and the output. A transmission system and a method for facilitating shifting of a transmission system are also provided.

An automatic transmission includes an input shaft, an output member, a first planetary gear set, a second planetary gear set, a third planetary gear set, a fourth planetary gear set, and an engagement mechanism. The engagement mechanism includes first to sixth engagement assemblies. Each of a plurality of gear ratios is provided by setting three of the first to sixth engagement assemblies in a engagement state.

A bicycle suspension system includes a control unit, a velocity sensor, and a cadence sensor. The control unit is configured to obtain gear ratio information of a bicycle to control an operating state of a suspension of the bicycle based on the gear ratio information. The velocity sensor is configured to detect a forward velocity of the bicycle and output a signal indicative of the forward velocity to the control unit. The cadence sensor is configured to detect a cadence of the bicycle crank and output a signal indicative of the cadence to the control unit. The control unit is configured to obtain the gear ratio information based on the forward velocity and the cadence.

A closed loop shift control apparatus and method based on estimated torque in friction elements controls a torque transfer phase when shifting from a low gear configuration to a high gear configuration for an automatic transmission system. When pressure actuated friction elements are selectively engaged and released to establish torque flow paths in the transmission, estimates of torsional load exerted on the off-going friction element are used to predict the optimal off-going friction element release timing for achieving a consistent shift feel. The estimated torque is preferably calculated by using estimated torque signals generated as a function of speed measurements represented either the engine speed and turbine output speed or transmission output speed and wheel speed under dynamically changing conditions.

RET antenna with motor and clutch assembly that is operative to mechanically disengage the DC motor and drive unit (also called the gear-motor unit) from the phase shifter adjustment shaft during a manual tilt operation. Disengaging the gear-motor unit removes the drag of the motor and the high gear ratio gear box from the phase shifter control rod making it easier to manually turn the phase shifter control knob. In addition, the clutch disengages the gear-motor without disengaging the position detector from the phase shifter control rod so that position calibration is not lost during manual tilt adjustment. When the manual tilt operation is completed, the mechanical tilt clutch enables the gear-motor unit to be reliably re-engaged with the phase shifter control rod for motorized electrical tilt operation without having to re-calibrate the position detector.

A hybrid vehicle 20 of the invention is equipped with a power distribution integration mechanism 40 and a transmission 60. The power distribution integration mechanism 40 is a double pinion planetary gear mechanism constructed to include a carrier 45 connecting with a motor MG2, a sun gear 41 connecting with a motor MG1, and a ring gear 42 connecting with an engine 22 and to have a gear ratio of approximately 0.5. The transmission 60 includes a three element-type first change speed planetary gear mechanism PG1, a three element-type second change speed planetary gear mechanism PG2, a brake clutch BC1 configured to fix a ring gear 62 of the first change speed planetary gear mechanism PG1 in a non-rotatable manner and release the ring gear 62 in a rotatable manner, and a brake clutch BC2 configured to enable and disable power transmission via the second change speed planetary gear mechanism PG2.

Methods and systems are provided for controlling a vehicle engine coupled to a stepped-gear-ratio transmission. One example method comprises, in response to a first vehicle moving condition, shutting down the engine and at least partially disengaging the transmission while the vehicle is moving; and during a subsequent restart, while the vehicle is moving, starting the engine using starter motor assistance and adjusting a degree of engagement of a transmission clutch to adjust a torque transmitted to a wheel of the vehicle.

A first rotor (24; 124) and a second rotor (25; 125) are arranged in a coaxial and mutually rotatable relationship and are provided with a first driven gear (41; 141) and a second driven gear (42; 142), respectively. A drive shaft (31; 131) is also provided with a first drive gear (43; 143) and a second drive gear (44; 144) which are commonly connected to an output shaft of an electric motor (32; 132), and mesh with the first and second driven gears, respectively, at slightly different gear ratios. The first and second rotors are connected via a thread feed mechanism (36; 136) that converts a relative rotation between the first and second rotors into an axial linear movement between the first and second rotors that is used for changing a distance between a vehicle body part and a corresponding end of a suspension spring in a vehicle height adjusting system (9; 109). Owing to a differential rotation of a high gear ratio between the first and second rotors, a significant torque amplification is possible with a compact arrangement. The use of spur gears instead of a worm gear mechanism minimizes torque loss.

A vehicle transmission includes a differential gear set having five coaxial gear elements and an output member. Two of the gear elements are controllable via torque transmitting mechanisms such as electric motors to establish a plurality of speed ratios between the input shaft and the output shaft. Two of the other gear elements are selectively operatively connectable to an output shaft via a gear arrangement that allows for a plurality of speed ratios between the gear elements and the output shaft. Additional torque transmitting mechanisms such as clutches are selectively engageable to provide continuously variable speed ranges between the input shaft and the output shaft, fixed gear ratios and an electric drive mode. The various speed ratios enable a plurality of compound split operating modes as well as an input split mode.

An apparatus and method are provided to execute synchronous shifting in a powertrain system having multiple torque-generative devices each operable to independently supply motive torque to the transmission device. The exemplary transmission device comprises a two-mode, compound-split, hybrid electro-mechanical transmission. Operation includes operating in an initial fixed gear ratio, operating the transmission in a mode operation, and, operating the transmission in a final fixed gear ratio. The control system reduces reactive torque of a clutch activating the initial gear, and deactivates the first torque-transfer device when the reactive torque is less than a predetermined value. It determines that speed of an input shaft to the transmission is substantially synchronized with a rotational speed of the second torque-transfer device, and actuates the second torque-transfer device.

Method for potentiating the utilizable torque output capacity of a hybrid electric vehicle is provided. The method includes controlling operation of an engine of a hybrid electric vehicle using a generator, the engine and generator being interconnected through a planetary gear system, the generator having approximately equal torque output capacity as the engine based on connective gear ratio selection. An engine controller is utilized for managing the engine's operation thereby permitting the engine to be operated at a torque output level substantially equal to the maximum torque output of the generator without a significant margin of excess control capacity of the generator over the engine. An overpower condition is detected in which the torque output of the engine is surpassing the maximum torque output of the generator. The engine is controlled to a torque output that is less than the maximum torque output of the generator.