A quick-release structure has: a shaft lever having a shaft lever external thread at one end thereof and a shaft lever internal thread at the other end thereof; a fixed seat sheathed on the shaft lever in a non-rotatable manner relative to each other. The fixed seat has an annular fixed seat engaging tooth on one end face thereof; a movable seat having an axially penetrating perforation, wherein the movable seat has an annular movable seat engaging tooth on one end face thereof, and the movable seat engaging tooth faces the fixed seat engaging tooth of the fixed seat; a spring abutting between the fixed seat and the movable seat; a spanner rod having a pivoting hole; and a connecting shaft, one end of which abuts on the spanner rod, and the other end of which has a connecting shaft external thread.

The present invention is related to durable, increased traction irrigation wheel systems and method of increasing traction and durability of an irrigation wheel. A segmented, fully enclosed, circular rotating drum may be provided with may be configured to rotate around a central axis. A system may have integrally placed flat sheets on a periphery of a segmented, fully enclosed, circular rotating drum, at least one traction projection, and perhaps even at least one influential traction enablement component.

Mechanical strength of a second shaft portion of a position fixing bolt is larger than that of a first shaft portion of a positioning bolt. Cross-sectional shape of a positioning through-hole, cross-sectional shape of the first shaft portion, cross-sectional shape of each of position fixing through-holes, and cross-sectional shape of each of the second shaft portions are designed so that a total dimension of a first clearance in a circumferential direction about the rotation center axis is larger than a total dimension of a second clearance in the circumferential direction, the second clearance formed between an inner peripheral surface of each of the position fixing through-holes and an outer peripheral surface of the second shaft portion of each of the position fixing bolts.

A composite rim for a bicycle wheel that has a wall of structural fibers incorporated in a thermosetting polymeric material and a plurality of spoke attachment seats. The composite material includes at least one layer of woven bi-directional fibers where some fibers are in a nominal direction substantially parallel to the circumferential direction of the rim and some fibers are substantially orthogonal to the circumferential direction of the rim.

An agricultural machine tool includes a wheel body which includes a hub, a rim and at least two arms which each connect the hub and the rim to each other. At least one aperture is provided between the two arms and the rim, and has a closed contour. The tool includes a component which forms an accessory having a profiled portion having a shape which generally corresponds to the closed contour, and a generally superficial portion which terminates the profiled portion. The profiled portion is introduced at one side of the wheel body into the aperture, closing the aperture by form-fitting cooperation. A set of fixing members ensures the retention of the component in a final position, in which the superficial portion moves into a flush state with the arms, at least in the region of the contour.

A method of manufacturing a large- or medium-sized wheel disk including using a punch or die in a first step of ironing a blank of a flat plate to a first-stage product. The first-stage product having a cylindrical rising portion with an axially non-constant thickness. The rising portion includes a thick portion located at a tip portion of the rising portion and a thickness-reduced portion which is a remaining portion of the rising portion excluding the thick portion. During the first step, only a portion of the blank corresponding to the thickness-reduced portion is ironed.

A firm-grip rim includes two walls, an internal ring, an external ring and two flanges. The walls extend in an annular manner. The internal ring is formed between the walls. The external ring extends around the internal ring and includes two lateral portions connected to the walls respectively. Each of the flanges extends outward from a corresponding one of the walls in a radial direction so that there is a corner between it and a corresponding one of the lateral portions of the external ring. Each of the flanges includes an internal side formed with a grip device.

A modular wheel-hub bearing unit having an outer flanged hub for mounting the unit on an upright of a vehicle, provided externally with an assembly surface and internally with a mounting seat; and a bearing provided with an outer ring, two inner rings and two rows of rolling elements arranged between the outer ring and the two inner rings. The bearing being mounted inside the assembly seat independently of the outer flanged hub and having an outer diameter, the dimensions of which are related to the dimensions of an outer diameter of the assembly surface of the flanged hub by a first coefficient () according to the relation: D2=*D1, where 0.800.95.

A foot pedal assembly and method of moving a wheel assembly from a stowed configuration to a deployed configuration is provided. The foot pedal assembly can be moved to a locked configuration, thereby securing the wheel assembly in a deployed configuration, by allowing a foot pedal of the foot pedal assembly to move away from a second position after moving the foot pedal from a first position to the second position. When in the locked configuration, the foot pedal assembly can be moved to an unlocked configuration by moving the foot pedal assembly back to the second position, thereby allowing the foot pedal assembly and the wheel assembly to move towards the first configuration and the stowed configuration, respectively. A pin extending from a cam assembly into a raceway of a raceway body travels through the raceway as the foot pedal assembly is moved between configurations.

Bearing for at least one supporting roller of a carriage, which supporting roller is supported on at least one bearing surface, comprising at least one axle device which can be rotated about at least one rotational axis, at least one rocker which is connected to the axle device such that it is reliably driven, wherein, at an end which lies opposite the axle device, the rocker has at least one first connecting device for connecting the rocker to the supporting roller, at least one spring device which is arranged mechanically between the axle device and/or the rocker on one side and at least one holding device on the other side, wherein a force which forces the supporting roller onto the bearing surface can be built up on the axle device and the rocker by means of the spring device, and at least one damping device, by means of which a rotational movement of the axle device about the rotational axis can be damped, characterized in that the spring device and the damping device are configured in one piece at least in regions by way of at least one torsion spring element which is of rubber-elastic configuration at least in regions.