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.

All-terrain vehicle, drive train for such a vehicle and method of its operation

Abstract: A personal all-terrain vehicle (ATV) includes an engine of vertical shaft type, which has a power output shaft extending vertically above the engine. The engine power output shaft carries one pulley assembly of a belt-type continuously variable transmission (CVT), the second pulley assembly is carried by a vertically extending shaft supported in a bearing assembly secured to the engine. The vertically extending shaft carries shaft power vertically to a level below the engine at which a gear unit of T-configuration is disposed. The T-configuration gear unit provides for selection. of forward/reverse directions of travel for the vehicle, and also provides for splitting of shaft power between forward and rear differentials of the vehicle.

Positive power transmission system

Abstract: A toothed power transmission belt and pulley system is disclosed wherein the belt has an endless substantially inextensible tensile member with teeth secured thereto, the teeth having a cross-sectional configuration composed of two circular intersecting arcs for meshing with mating, conjugate, curvilinear pulley teeth. The size of teeth, length of radii of curvature, and the angles and point of intersection are determined by a set of design criteria and formulas as recited herein.

Dual-direction pulley system

Abstract: A dual-direction pulley system is disclosed in conjunction with an exercise machine. The pulley system provides resistance to a pivotally mounted actuator lever when the lever is rotated clockwise and when the lever is rotated counterclockwise. In a preferred embodiment the dual-direction pulley system provides resistance for a seated leg curl/extension exercise machine such that a user can perform leg curls and leg extensions from a single seated position.

Constant torque range-of-motion splint

Abstract: This is a range of motion splint (10) for applying constant torque across a joint undergoing rehabilitative therapy. The splint (10) includes a first brace section (12) and a second brace section (14). A first arm (18) extends from the first brace section (12) and a second arm (20) extends from the second brace section (14). The first and second brace section arms (18 and 20) are pivotally connected about a splint pivot axis by a pivot mechanism (24). A driven pulley (42) is mounted to the second arm (20) about the splint pivot axis. A drive pulley (56) is rotatably mounted to the first arm (18) about a drive axis which is spaced from the splint pivot axis. Torque is applied to the drive pulley (56) with respect to the first arm (18) by a spiral spring (50) positioned about the drive axis. A belt (30) couples the drive pulley (56) and the driven pulley (42). The amount of torque applied between the brace sections can be adjusted by a torque adjusting mechanism (52 and 54) which winds and unwinds the spring (50). An adjustable stop mechanism (80) can be used to limit the range of rotational motion between the brace sections. The brace section can be locked with respect to one another by a locking mechanism (66) which engages and prevents movement (52 and 54) of the drive pulley (56).

Trigger Finger Release with Hand Surface Landmark Ratios: An Anatomic and Clinical Study

Abstract: The purpose of this study was to identify surface landmark ratios to locate the A1 pulley and clarify the controversy of differing anatomic descriptions of the A1, C0, and A2 pulleys. Minimally invasive and percutaneous approaches to A1 pulley release may be facilitated with surface landmark ratios, which identify and predict the proximal and distal margins of the A1 pulley. Two-hundred fifty-sixty fingers were dissected in 64 preserved cadaver hands. Measurements of A1 pulley lengths and pulley margins in relation to surface landmarks were obtained. We found that the distance from the palmar digital crease to the proximal interphalangeal crease (mean, 2.42 +/- 0.03 cm) corresponds to the distance of the proximal edge of the A1 pulley from the palmar digital crease (mean, 2.45 +/- 0.03 cm). The mean absolute difference between these two measured distances in each finger was 0.13 cm, with a 95 percent confidence interval of 0.11 to 0.14 cm. Thus, the distance between the palmar digital crease and the proximal interphalangeal crease can be used to predict the distance between the palmar digital crease and the A1 pulley proximal edge with reasonable accuracy. A1 pulley length averaged 0.98 +/- 0.02 cm for the small finger and 1.17 +/- 0.02 cm for the index, middle, and ring fingers. The length of the A1 pulley was significantly shorter (p < 0.001) for the small finger than for the index, middle, and ring fingers. Additionally, a cruciate (C0) pulley was consistently located between the A1 and A2 pulleys, an average of 0.46 cm proximal to the palmar digital crease, which can serve as guide for concluding the release of the A1 pulley. Clinically, hand surface landmark ratios were used to release 32 trigger fingers with a minimally invasive technique, without a complication during 4- to 30-week follow-up. We conclude that hand surface landmark ratios can serve to locate the proximal A1 pulley edge, thus facilitating complete trigger finger release by either open or minimally invasive techniques. Additionally, our study clarifies the discrepancy of prior smaller reports of the pulley system anatomy regarding the existence of the C0 pulley between the A1 and A2 pulleys. The cruciate fibers of this C0 pulley can serve as the distal boundary for release of trigger finger.