Home » All Programs  Calculator Description  # Weight Lifting (systems)

## Subject

Mechanical advantage is a term used to describe the act of moving an object with less force than its weight, which can be achieved using levers, gears, screws, hydraulics, sheave-blocks and/or pulleys of different diameter.

Each method offers a greater capacity (weight) or faster lift dependent upon the relative input and output radii or diameters.

Whilst the calculations in Weight Lifting refer specifically to the mechanical advantage associated with lifting heavy weights, these calculations also apply to mechanisms or parts thereof that apply a force to another part of the mechanism in order to move it or lock it in place.
Moreover, some of the calculation options also apply to enhanced movement if the radii are reversed (i.e. R<r), wherein the weight (or Force) factor (Fʷ) will be less than 1 and the velocity (or movement) factor (Fᵛ) will be greater than 1

## Calculator

The weight lifting calculator includes eight calculation options (lift configurations) using the above-mentioned systems or combinations thereof.

Weight Lifting calculates the following two factors:

Lift Factor; is a multiplier you use to identify the weight you can lift for any given input force

Velocity Factor; is a multiplier you use to identify the lift velocity or movement of the weight in comparison with that of the applied force

You simply multiply your applied force or movement (or velocity) by the appropriate factor

For help using this calculator see Technical Help

## Weight Lifting Calculator - Options

The weight lifting calculator provides 9 different lifting systems some of which offer a better lifting factor and others that provide an improved speed factor.

#### Torque Pulleys

This system utilises a torque advantage via a large diameter input pulley and a small-diameter pulley, to which it is attached, to lift the weight.

You enter: and the weight lifting calculator will provide:
• Weight factor
• Velocity factor

#### Sheave Block

This system utilises multiple cord drops between two similar-sized multi-roller sheave blocks that reduce the force required to lift any given weight by sharing the weight equally between each cord drop.

You enter: and the weight lifting calculator will provide:
• Number of pulleys
• Pay-out angle
• Anchor angle
• Weight factor
• Velocity factor

#### Differential Pulley

This system utilises a torque advantage via a large diameter input pulley and a small diameter output pulley, to which it is attached, to lift the weight, via a third detached pulley around which the output-cord is wrapped. The differential pulley system achieves a lesser mechanical advantage that the Pulley system, but benefits from the use of a continuous loop (pull-cord).

You enter: and the weight lifting calculator will provide:
• Weight factor
• Velocity factor

#### Worm & Wheel Pulley

This system utilises a torque advantage via a large diameter input pulley and a small diameter output pulley, to which it is attached, to lift the weight, via a third detached pulley around which the output-cord is wrapped. The input pulley is driven by a worm and wheel, which significantly improves the lift capacity by at the cost of speed.

You enter: and the weight lifting calculator will provide:
• Torsion bar length
• Weight factor
• Velocity factor

#### Gears

This system utilises multiple large to small pairs or gears that connect a large input pulley to a small output pulley. Weight Lifting accommodates up to 5 gear pairs.

You enter: and the weight lifting calculator will provide:
• Input radius (1 to 5)
• Output radius (1 to 5)
• Weight factor
• Velocity factor

#### Screw Jack

This system achieves a very good mechanical advantage via a screw thread and a long turning handle but at the cost of speed, which is much reduced.

You enter: and the weight lifting calculator will provide:
• Torsion bar length
• Friction coefficient
• Weight factor
• Velocity factor

#### Lever

This system achieves a mechanical advantage via a long input lever-arm verses a much shorter weight lifting arm.

You enter: and the weight lifting calculator will provide:
• Length to force
• Length to weight
• Weight factor
• Velocity factor

#### Hydraulic Jack

This system achieves a mechanical advantage via an input force applied to a small diameter hydraulic cylinder and a much larger weight lifting cylinder, both of which are exposed to the same fluid pressure.

You enter: and the weight lifting calculator will provide:
• Input diameter
• Output diameter
• Weight factor
• Velocity factor

Price: £20.00

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