A quick release mechanism for a wheel includes a hub and a clip, which interact with a wheel or roller that may or may not be part of the invention per se. The hub is disposable on a drive shaft such that it will rotate with the drive shaft. An optional hub cap is disposable on the wheel and has an opening that is complimentary to the geometry of the hub to allow engagement thereof such that the hub the hub cap rotate together. The clip is disposable on the hub in a closed or an open position so that the hub cap cannot or can be removed from the hub.

A media cutting system is disclosed comprising a die cutter including a cutting surface and a plurality of dies stored proximate the cutting surface, a die exchange system including a die storage system configured to support the plurality of dies and a die transport system, and a computer system comprising a controller configured to operate the die transport system and the die cutter. A die exchange system and methods of making and using the die exchange system also are disclosed.

A drive system for a vehicle is disclosed. The drive system has a track supported by pulleys; at least one wheel, disposed near an end of the track; and at least one flipper. The at least one flipper has at least one of a flipper track supported by flipper pulleys and a flipper wheel. A diameter of the at least one wheel is larger than a combined diameter of: each of the pulleys of the track and twice a thickness of the track.

An electric power steering system includes a joint that connects a rotary shaft of an electric motor with a worm shaft of a speed reducer. The joint includes a first rotational element that has a boss into which a first end portion of the worm shaft is press-fitted, and a flange extending radially from the boss. The first bearing is held by a housing and supports the first end portion so that the first end portion is rotatable and movable in an axial direction. A first elastic body, which urges the worm shaft in the axial direction toward the electric motor through the first rotational element, is provided between an inner ring of the first bearing and the flange.

A single drive three pivot fork lift truck includes a steering bridge, a steering motor that drives the steering bridge, and at least one rear wheel that is connected to the steering bridge. The forklift truck also includes a first sensor that senses rotational position of a steering wheel, a second sensor that senses rotation of the steering motor, and a controller that receives signals from the first sensor and second sensor and controls the steering motor. The forklift truck also includes a battery carried by the truck frame in a battery compartment located at the rear of the forklift truck, which can take the place of counterweight blocks.

A single drive three pivot fork lift truck includes a steering bridge, a steering motor that drives the steering bridge, and at least one rear wheel that is connected to the steering bridge. The forklift truck also includes a first sensor that senses rotational position of a steering wheel, a second sensor that senses rotation of the steering motor, and a controller that receives signals from the first sensor and second sensor and controls the steering motor. The forklift truck also includes a battery carried by the truck frame in a battery compartment located at the rear of the forklift truck, which can take the place of counterweight blocks.

A ground robot having a main body, two opposing drive systems, a flipper disposed distal to the main body, and a front wheel and a rear wheel, both disposed substantially parallel to the vertical plane and between the inner track and the flipper. The main body has a sagittal plane and two opposing lateral sides. Each drive system having an inner track disposed proximal to the main body. The inner track extends along a corresponding lateral side of the two opposing lateral sides and substantially parallel to a vertical plane of the main body, and is supported by a plurality of inner pulleys. The flipper extending along the corresponding lateral side and substantially parallel to the vertical plane. The flipper has a flipper body, an outer track, and a plurality of outer pulleys supporting the outer track. The diameter of the front wheel and the rear wheel of each of the opposing drive systems ranges between 1.2 to 1.3 times of a diameter of the inner track.

A ground robot having a main body, two opposing drive systems, a flipper disposed distal to the main body, and a front wheel and a rear wheel, both disposed substantially parallel to the vertical plane and between the inner track and the flipper. The main body has a sagittal plane and two opposing lateral sides. Each drive system having an inner track disposed proximal to the main body. The inner track extends along a corresponding lateral side of the two opposing lateral sides and substantially parallel to a vertical plane of the main body, and is supported by a plurality of inner pulleys. The flipper extending along the corresponding lateral side and substantially parallel to the vertical plane. The flipper has a flipper body, an outer track, and a plurality of outer pulleys supporting the outer track. The diameter of the front wheel and the rear wheel of each of the opposing drive systems ranges between 1.2 to 1.3 times of a diameter of the inner track.

An assembly includes a steering shaft and a primary drive system eccentrically coupled to the steering shaft and configured to transfer a torque applied to the steering shaft to a vehicle steering system. The assembly also includes a secondary drive system coupled to the steering shaft and configured to transfer the torque applied to the steering shaft if the primary drive system is inactive and substantially unable to transfer the torque.

The present disclosure relates to a rack assist type power steering apparatus that includes: a ball nut that is rotated by the rotating force transmitted from a motor and has an internal screw groove formed in the inner circumferential surface thereof; and a rack bar that has an external-screw-groove-formed part that has an external screw groove formed in the outer circumferential surface thereof, and is coupled with the ball nut by a ball, wherein the external screw groove has a first curved portion and a second curved portion connected to each other, and is formed such that a contact angle formed by a line that is normal to a tangent line at a point where the ball makes contact with the first curved portion and a line that is normal to a tangent line at a point where the ball makes contact with the second curved portion gradually decreases from the central portion toward opposite end portions of the external-screw-groove-formed part, thereby reducing friction generated when the ball performs a rolling motion in the middle of the external screw groove that is formed in the rack bar and distributing the load acting on the ball in the opposite end portions of the external screw groove that is formed in the rack bar.