4163 results about "Continuously variable transmission" patented technology

Inventive embodiments are directed to components, subassemblies, systems, and/or methods for continuously variable transmissions (CVT) having a variator provided with a plurality of tilting, traction planets and traction rings. In one embodiment, a variator is coupled to a rangebox to provide multiple operating modes. In another embodiment, a hydraulic system is configured to control the transmission ratio of the variator and the rangebox. Various inventive shift-cam-and-sun subassemblies can be used to facilitate shifting of the transmission ratio of a CVT. Embodiments of a transmission housing and bell housing are adapted to house components of a CVT and, in some embodiments, to cooperate with other components of the CVT to support operation and/or functionality of the CVT. Various related devices include embodiments of, for example, a pivot arm, a control feedback mechanism, axial force generation and management mechanisms, a control valve integral with an input shaft, a pivot pin hub, and a rotatable carrier configured to support planet-pivot arm assemblies. FIG. 72 shows a torque-split ball-type rolling traction CVT with a ball-type rolling traction variator (1200) and planetary gearset (1400) which is followed by a rangebox (1600).

Traction planets and traction rings can be operationally coupled to a planetary gearset to provide a continuously variable transmission (CVT). The CVT can be used in a bicycle. In one embodiment, the CVT is mounted on the frame of the bicycle at a location forward of the rear wheel hub of the bicycle. In one embodiment, the CVT is mounted on and supported by members of the bicycle frame such that the CVT is coaxial with the crankshaft of the bicycle. The crankshaft is configured to drive elements of the planetary gearset, which are configured to operationally drive the traction rings and the traction planets. Inventive component and subassemblies for such a CVT are disclosed. A shifting mechanism includes a plurality of pivot arms arranged to pivot about the centers of the traction planets as a shift pin hub moves axially.

A continuously variable transmission is mounted on a vehicle capable of selecting plural drive modes and changes a target engine speed between drive modes. A pulley ratio is controlled by a motor. An ECU for transmission control includes a calculation section which outputs a target engine speed as a function of throttle opening and vehicle speed, and a motor control value determination section which outputs a control value for controlling the motor based on the target engine speed and an actual engine speed. In a case where, when a drive mode is selected, the current target engine speed changes by an amount exceeding a predetermined judgment value according to vehicle speed, the motor control value determination section updates the current target engine speed in a stepwise manner. The resulting configuration reduces a shift shock caused by a drive mode change.

To provide a continuously variable transmission and a control method thereof, allowing for control of the axial position of a movable sheave without a sensor for measuring the axial position of the movable sheave on a rotational shaft and for stable control with the movable sheave being held in position, without the increase in the size of mechanisms and power consumption.

A continuously variable transmission in which, on a rotational shaft 1 thereof are mounted a fixed sheave 2 positioned in the axial direction and a movable sheave 3 slidable axially, so as to face each other, a motor is provided for driving the movable sheave, and a slide driving means 16 is provided for sliding the movable sheave 3 axially by the rotation of the motor, characterized in that: the motor is a step motor 6, and the step motor 6 and the slide drive means 16 are mounted coaxially with the rotational shaft 1.

Inventive embodiments are directed to components, subassemblies, systems, and/or methods for continuously variable accessory drives (CVAD). In one embodiment, a skew-based control system is adapted to facilitate a change in the ratio of a CVAD. In another embodiment, a skew-based control system includes a skew actuator coupled to a carrier member. In some embodiments, the skew actuator is configured to rotate a carrier member of a CVT. Various inventive traction planet assemblies can be used to facilitate shifting the ratio of a CVT. In some embodiments, the traction planet assemblies include legs configured to cooperate with the carrier members. In some embodiments, a traction planet assembly is operably coupled to the carrier members. Embodiments of a shift cam and a traction sun are adapted to cooperate with other components of the CVT to support operation and/or functionality of the CVT. Among other things, shift control interfaces for a CVT are disclosed.

A continuously variable transmission is disclosed for use in rotationally or linearly powered machines and vehicles. The transmission provides a simple manual shifting method for the user. Further, the practical commercialization of traction roller transmissions requires improvements in the reliability, ease of shifting, function and simplicity of the transmission. The present invention includes a continuously variable transmission that may be employed in connection with any type of machine that is in need of a transmission. For example, the transmission may be used in (i) a motorized vehicle such as an automobile, motorcycle, or watercraft, (ii) a non-motorized vehicle such as a bicycle, tricycle, scooter, exercise equipment or (iii) industrial equipment, such as a drill press, power generating equipment, or textile mill.

Inventive embodiments are directed to components, subassemblies, systems, and/or methods for auxiliary power units (APU). In one embodiment, the APU includes a source of rotational power such as a combustion engine operably coupled to a continuously variable transmission (CVT). The CVT can be coupled to a load. In some embodiments, the load is provided by a generator. In one embodiment, the APU has a control system configured to control the operation of the engine and the operation of the CVT. The control system can facilitate substantially constant speed operation of the generator in the presence of variable operation of the engine. In another embodiment, the APU includes a continuously variable accessory drive (CVAD) operably coupled to an engine. The CVAD can include a continuously variable transmission operably coupled to a generator. In one embodiment, a skew-based control system is adapted to facilitate a change in the ratio of a CVAD.

A transmission having a plurality of tilting balls and opposing input and output discs provides an infinite number of speed combinations over its transmission ratio range. The transmission provides multiple powerpaths and can be combined with electrical components to provide motor/generator functionality, which reduces the overall size and complexity of the motor and transmission compared to when they are constructed separately. In one embodiment, rotatable components of a continuously variable transmission are coupled separately to an electrical rotor and to an electrical stator so that the rotor and stator rotate simultaneously in opposite directions relative to one another. In other embodiments, an electrical rotor is configured to transfer torque to or from a disc that is in contact with a plurality of speed adjusters, while an electrical stator is configured to transfer torque to a shaft that is operationally coupled to the speed adjusters via an idler.

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 continuously variable transmission apparatus, has: an input shaft; a toroidal-type continuously variable transmission; a rotation transmission shaft; first, second and third planetary-gear-type transmissions; a first power transmission mechanism; a second power transmission mechanism; a third power transmission mechanism; and, a switching mechanism, wherein the second sun gear and one of the first and third sun gears are rotated together with the rotation transmission shaft to thereby execute the power transmission through the rotation transmission shaft and one of the first and second planetary-gear-type transmissions, and, in a state where the power transmission through the third planetary-gear-type transmission is cut off, in accordance with the control of the transmission ratio of the toroidal-type continuously variable transmission, the output shaft is stopped while the input shaft is rotating.

A transmission or actuator offering multiple rotational outputs proportionate in speed to that of a common rotational input, each output according to its own ratio. The ratios are continuously variable between positive and negative values, including zero, and may be varied by electromechanical actuators under computer control. The transmission relates the output speeds one to another under computer control, and thus makes possible the establishment of virtual surfaces and other haptic effects in a multidimensional workspace to which the transmission outputs are kinematically linked. An example of such a workspace is that of a robotic or prosthetic hand.

A continuously variable transmission apparatus, has: an input shaft; a toroidal-type continuously variable transmission; a first rotation transmission shaft; a first planetary-gear-type transmission; a second planetary-gear-type transmission; a second rotation transmission shaft; an output shaft; a first power transmission mechanism; a second power transmission mechanism; and a switching mechanism, wherein, in a state where the power transmission through the first power transmission mechanism is allowed and the power transmission through the second power transmission mechanism is cut off, in accordance with the control of the transmission ratio of the toroidal-type continuously variable transmission, the output shaft be stopped while leaving the input shaft rotating.

The present invention achieves construction of a toroidal continuously variable transmission of which manufacture, management and assembly of parts can be performed easily, reduction of cost is easy and speed change operation is stabilized. This construction comprises support holes 28 having a circular cross section that are formed in part of the outer rings 16f, column shaped anchor pins 26 that, when fitted and fastened inside the support holes 28 with an interference fit, part of the anchor pin 26 protrudes from the inside surface of a concave section 23e of the outer ring 16f, and anchor grooves 27 that are formed in cylindrical convex surfaces 22e of support beam sections 9f of the trunnions 7f in the circumferential direction of the cylindrical convex surfaces 22e; wherein, the engagement sections where the parts of the anchor pins 26 engage with the anchor grooves 27 can support torque that is applied to the power rollers 6a as the input and output disks 2, 5 rotate.

A toroidal-type continuously variable transmission, has a first continuously variable transmission mechanism and a second continuously variable transmission mechanism: wherein the first and second continuously variable transmission mechanisms are disposed coaxially with each other; the first and second input disks are connected together so as to be rotated in synchronization with each other; the first and second output disks are formed as a unified type output disk including traction surfaces on the two side surfaces thereof; on the side portion at the outer-most outside diameter of the unified type output disk, there is formed a datum plane serving as a machining datum when the traction surfaces are processed; and, an operation for finishing the datum plane is carried out after the unified type output disk is heat treated.