Sensor Accessories The Spoked Pulley (Product No. 3177)
Pulley wheel
Mounting Bracket Pozidriv Screw
Data Harvest Group Ltd. 1 Eden Court, Leighton Buzzard, Beds, LU7 4FY Tel: 01525 373666 Fax: 01525 851638 e-mail: sales@data-harvest.co.uk www.data-harvest.co.uk
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Data Harvest. Freely photocopiable for use within the purchasers establishment
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The Spoked Pulley
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Introduction The Spoked Pulley Accessory is a low friction pulley with 10 spokes. If a length of thread is run in the groove of the pulley wheel and turns the pulley as it moves, the distance moved by the thread can be calculated. The movement of cord as the pulley revolves is partially dependent upon the thickness of the cord used. The pre-defined measurements for the Data Harvest Spoked Pulley are calculated for use with 1.5 mm diameter cord. The Pulley cannot determine direction or change in direction and is therefore only suitable for use where movement is in one direction only. The Pulley can be used in conjunction with Smart Q Sensors such as the Light Gate or the Rotary Motion Sensor.
Attaching the Pulley Slide the Pulleys mounting bracket in between the two ridges on the Smart Q Sensor so the hole in the bracket lines up with the mounting thread. Screw into position using the pozidriv pan-head screw (supplied with the Pulley).
Spoked pulley
Centre of the Light gate
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The Spoked Pulley
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Using the Spoked Pulley 1. The Light Gate When the Pulley is in position and rotates, its spokes will block the infrared beam of the Light Gate, which can then be used to monitor the rotation of the pulley. 2. The Rotary Motion Sensor The Pulley can be used to convert movement from one angle to another or just as a guide for the cord. 3. The Dynamics System The Spoked pulley can be used simply as a guide for a length of cord.
For example: the Pulley can be attached to the end of the track using a thin bracket. A length of cord (with mass carrier attached) is connected to the cart and the cord is run over the top of the pulley. When the mass is released the cart will move along the track.
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The Spoked Pulley
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The Spoked Pulley can be attached to a Light Gate and fitted to the end of the track. This arrangement can be used to time the movement of the cart in order to study the effect of changing mass, altering the angle of the track, etc.
A Spoked Pulley/Light Gate can be attached to the pillar to make an Attwood’s machine. A length of cord is run over the pulley and a mass carrier attached to each end of the cord.
What can it be used to measure Distance at A The Pulley can be attached to a Light Gate, which is connected to Input A, to measure distance moved. Distance is calculated using the step size of the pulley. Each time a new gap in the Pulley is reached; the distance moved is known. Speed at A or Acceleration at A When a Spoked Pulley is used to measure speed or acceleration, the measurements shown are for instantaneous values e.g. i.e. it took this amount of time to travel this distance and the speed was. The spokes on the pulley can easily interrupt the Light Gates beam to create false results. Wait until all is ready before you click on the Start icon.
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The Spoked Pulley
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Practical information
Do not over tighten the pozidriv screw. Check the cord is running in the groove of the Pulley. Do not allow moving objects to collide with the Pulley. Use the On/Off indicator (red LED) on the Light Gate to check whether a spoke is blocking the infrared beam before the investigation starts.
Technical data Diameter of Pulley measured inside the groove: 45.5 mm Diameter of Pulley on the edge: 50 mm Circumference of the wheel measured in the V groove: 143 mm Circumference on the edge of the groove: 157 mm Screw Size: M6 x 12 mm pozidriv pan-head
Limited warranty For information about the terms of the product warranty, see the Data Harvest website at: https://data-harvest.co.uk/warranty. Note: Data Harvest products are designed for educational use and are not intended for use in industrial, medical or commercial applications.
WEEE (Waste Electrical and Electronic Equipment) Legislation Data Harvest Group Ltd are fully compliant with WEEE legislation and are pleased to provide a disposal service for any of our products when their life expires. Simply return them to us clearly identified as ‘life expired’ and we will dispose of them for you.
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