Pulley

About: Pulley is a research topic. Over the lifetime, 51636 publications have been published within this topic receiving 178220 citations. The topic is also known as: drum & block.

Medical device control handle with multiple puller wires

Abstract: A medical device control handle or catheter includes deflection assembly and at least one of the following: a disk actuator, a lever actuator and a ring actuator for actuating additional puller wires in manipulation of multiple features of the medical device or catheter independently of each other. The disk actuator has a common rotational axis with the deflection assembly as the disk actuator is mounted on a portion of the pulley arm but is rotationally independent of the pulley arm. The lever actuator has a separate rotational axis from that of the pulley arm and can be distal of the pulley arm with its rotational axis is oriented generally perpendicular of the rotational axis of the pulley arm. The ring is mounted outside of the control handle and rotatable relative to the control handle to actuate another puller wire for manipulating another feature of the catheter. Each of the disk, lever and ring actuators are of a design that allows existing control handles and catheters to be readily modified to include these actuators.

Self-propelled vehicle for movement within a tubular member

Abstract: A self-propelled vehicle (20) for movement within a tubular member (22) includes propulsion mechanisms (28) distributed about a core element (24). Each of the propulsion mechanisms (28) includes a drive belt (28). A first pulley (34), a second pulley (36), and a mid-roller assembly (38) are encompassed by and engage the drive belt (28). The mid-roller assembly (38) is spring-loaded for providing an outwardly-directed force (40) to an underlying portion (42) of the drive belt (28) to press the drive belt (28) against an inner wall (44) of the tubular member (22). A motor arrangement (46), in communication with the propulsion mechanisms (28), actuates one of the first and second pulleys (34, 36) to rotate the drive belt (28) in contact with the inner wall (44) of the tubular member (22) thereby moving the vehicle (20) within the tubular member (22).

Belt and belt drive assembly

Abstract: A flexible power transmission belt used in conjunction with toothed and/or grooved pulleys of a belt drive assembly and capable of driving from opposite portions thereof. The belt includes one driving portion which is preferably transversely toothed to mesh with toothed pulleys and an opposite longitudinal plural V-ribbed driving portion which engages at least one grooved pulley. The belt is particularly useful in belt drive assemblies in which the arc of contact between the plural Vribbed driving portion of the belt and the pulley is small or relatively small with the required high tension materially increasing stresses on the tension member of the belt.

Microslip friction in flat belt drives

Abstract: The microslip shear model of belt mechanics is extended to fully incorporate belt inertia effects and used to analyse the steady state of a two-pulley drive. The belt is modelled as an axially moving string consisting of a tension-bearing member and a pliable elastomer envelope. Relative displacement between the tension-bearing member and the pulley surfaces shears the elastomer envelope, transferring the friction from the pulley surface to the tension-bearing member. The belt-pulley contact arcs consist of adhesion and sliding zones. Static friction exists in the adhesion zones, whereas kinetic friction exists in the sliding zones. An iteration method involving one outer and two inner loops is proposed to find the steady mechanics, including the sliding and adhesion zones, belt-pulley friction, and belt tension distribution. The outer loop iterates on the tight span tension similar to that used in published creep models. Two inner loops iterate on the tight span and driven pulley speeds respectiv...