Sri International

Murphy Kitchell

Alexander Steele Kernbaum

Thomas D Egan

Reuben Daniel Brewer

John R Marlow

Gordon Kirkwood

A variety of shifter mechanisms are provided for controlling the axial distance between half-pulleys of a split pulley variable transmission, thus controlling the transmission ratio of the variable transmission. Some of these embodiments include a differential such that a variable transmission can be driven and shifted differentially by two inputs. A torque or rotation difference between the inputs results in a change in the transmission ratio and in-common torque or rotation is transmitted through the transmission to an output. The same motors used to drive the output of the transmission are thus also able to effect shifts in the transmission ratio. Accordingly, motor mass that is not being used to effect high-speed shifts may be used to drive the transmission output, and vice versa. The provided shifter embodiments are well-suited to application to nested-pulley variable transmissions, including nested-pulley infinitely variable transmissions.

Shifting mechanisms for split-pulley variable transmissions

A variety of mechanisms are provided for coupling the rotation of shafts or other mechanical elements having parallel but offset axes of rotation. The coupling mechanisms can couple such input and output elements via pins that are in contact with the input and output elements. The pins, upon rotation of the input and output elements, can engage in substantially pure roiling motion with respect to respective contact surfaces on the input and output members. Accordingly, the pins can reduce the number of bearings and increase efficiency relative to alternative coupling mechanisms. Such couplings may be employed in a variety of applications, including the coupling of rotations between elements of a cycloidal drive or a transmission that includes a member that undergoes cycloidal motion. For example, this coupling could replace the cage gear of a cycloidal drive in coupling the output to the cycloidal disc of a cycloidal drive.

Shaft couplings

A variety of transmissions, and improvements thereof, are provided having improved efficiency and other benefits. The transmissions include one or more inner members that are driven by one or more cams or other means to engage in precessional rotation about an axis of rotation that, itself, orbits about a primary axis of rotation. A plurality of shaped rollers are in contact with shaped cutouts on the inner member(s) and on a ground member such that an input rotation/torque applied via the cam is realized as an output rotation/torque at an output member that is coupled to the inner member(s). Tire rollers and contact surfaces are shaped such that the rollers engage in rolling motion relative to the contact surfaces, providing improved efficiency. Multiple inner members, and corresponding sets of shaped rollers, can be provided to increase power capacity, reduce torque ripple, reduce wobble, or provide other benefits.

Pure rolling cycloid transmissions with variable effective diameter rollers and roller constraints

A variety of transmission mechanisms are provided that include split pulleys nested within each other in order to reduce the size of the transmissions, to provide infinitely variable transmission ratios that include forward and reverse ratios, or to provide some other benefits. The transmissions include multiple inner split pulleys nested within an outer split pulley. Two, three, or more inner split pulleys can be disposed within the transmission to balance the mass of the inner split pulleys in order to reduce vibration and internal stresses experienced by the transmission. This can increase the lifespan of the transmission, reduce wear, and increase efficiency. Additionally, providing multiple inner split pulleys in a nested configuration can allow for reduction of loads transmitted through bearings of the transmission.

Variable transmissions with nested pulleys

A variable transmission may include a segmented pulley and a nested pulley located at least partially within the segmented pulley. The spacing between the components of the first segmented pulley may be varied to alter the transmission ratio of the variable transmission by altering the effective diameter of the segmented pulley. The nested pulley may also be a segmented pulley. In some embodiments, one of the pulleys may be rotationally fixed, and the variable transmission may comprise a compact infinitely variable transmission. The eccentricity of the compact infinitely variable transmission may be significantly less than the eccentricity of other infinitely variable transmission designs. In other embodiments, a nested pulley structure may be used to provide a compact continuously variable transmission.

Compact infinitely variable transmission

Systems are provided for gripping or otherwise manipulating lettuce, sliced foodstuffs (e.g., sliced cheese, sliced tomato or other sliced vegetables), or other foodstuffs or other irregular objects or substances. These systems can facilitate the manipulation of groups of irregular objects, including distributing small amounts (e.g., individual instances) of such groups of objects. These systems operate to manipulate such objects by extending and retracting rods, wires, or otherwise-configured pins to contact and/or penetrate the object(s) to be manipulated. In some examples, the pins are retracted to individually dispense objects (e.g., slices of cheese) from a stack of objects. In some examples, the separation and angle of the pins can be controlled to, e.g., grip one or more irregular objects and subsequently to dispense some or all of the gripped object(s).

Growing community of inventors

Mountain View, CA, United States of America

Murphy Kitchell