B. AD/de] ]/99

Transcription

1 B AD/de] ]/99 TECHNOLOGY AND SCIENCE KITS

2 IT INTRODUCTION: The TASK range is intended to provide supported and relevant learning opportunities to students on science, technology and engineering programmes. The products extend across a wide range of ages and abilities. They are adaptable, simply constructed, robust and easy to use. The onus on design has been for repeatability, conceptual application and quality. User Guide The assembly documentation sent with the equipment is in two parts; these are for: 1) The Teacher (Pages 1T to 8T) Some TASK equipment may already be built and tested in which case this guide will give basic instructions for installation. Other TASK equipment may be in kit form the aim of the Teacher guide in this case is to give instructions of how to get the equipment up and running, from the kit form you receive it in, up into student modules. Some of the assembly may be beyond the ability of many students, some may not; this decision is left to the practitioner. Flexibility is the key. The second aim is to give you, the practitioner, an insight into the equipment and its potential uses rather than being a totally prescriptive text. This is mainly due to the myriad of technology courses and levels that the equipment is suitable for, and to allow for adaptability and flexibility. In the light of this TecQuipment produces student work programmes for specific courses which are mapped against curriculum, syllabi or, in the case of NVQ and GNVQ, units and elements. This document should be retained for future reference as it contains information relating to the safe use and maintenance of the equipment (where applicable). 2) The Student (Pages 15 to 25) The Students Guide is intended to provide a basic guide to setting up the equipment. Exact experimental procedures are left to either the practitioner, using this document for reference, or those found in the TecQuipment student work programmes. This allows the sheets to be a "universal guide" which can be used across courses and abilities.

3 2T THE EQUIPMENT: The bulk of the equipment is based around a frame, which has a grid of holes of 6.4mm diameter on a 10mm pitch. This grid comes in two forms: the first is the miniframe, which can be stood upright using its bolt on feet or laid flat on a workbench. The second is the universal frame, which can be stood upright on a workbench, using the same bolt on feet as the miniframe, but can also be clamped to the edge of the workbench (up to 80mm (3") thick) to provide a sturdy working base. Other equipment is stand-alone and does not rely on having a frame although the same design concepts have been used throughout. The equipment can be split into four main functional groups indicated by a colour; these are: Blue - A base or frame, i.e. the universal frame or miniframe White - Instrumentation, control and electrical Yellow - Experimental components - mainly stationary or passive Red - Experimental components - mainly rotational, speeding, or containing energy REFERENCE: The following books are helpful in providing theory and background information on the topics covered by this kit: GNVa in Engineering Edited by N. Lehup Longman GNVa in Science Edited by N. Lehup Longman Motor Vehicle Engineering Science by S. J. Zammit Longman Engineering Science by E. Hughes and C. Hughes Longman Post 16 Publications Publications TO GNVO Delivery Modules Technology Enhancement Programme Technology Enhancement Programme TecQuipment Limited

4 3T THE COMPOUND PULLEY KIT SHOULD CONTAIN: A Pulley Block Back Plate [ ==::] D A Pulley Block Front Plate Q e...s"\ 2 Moving Retaining Plates. 'I E :=;?) A Pulley ASSembIY A Pulley ASSembIY A Pulley ASSembIY (Large) (Medium) (Small) I I 8 Fixing Rings (2 Spares) 8X eb 4x II...>"\ 5 18mm M3 Spacers 5X A Cord Assembly t;f:;; A Nut and Bolt Kit

5 4T 1. Take out 3 of the Spacers and squeeze 2 Fixing Rings onto each one leaving a gap in between each Ring. 01 "'---""' / - "'"'" V' I / <", i. \ ' 0 / '" 2. Attach 2 Spacers with fixing rings onto one of the Moving Retaining Plates as shown. Now attach the other Moving Retaining Plate to the Spacers with the Small Pulley Assembly in between. : )- ==t:=::=:> 3. Attach 1 Spacer with fixing rings and 2 Spacers without fixing rings onto the Pulley Block Front Plate in the positions illustrated. Now attach the Pulley Block Front Plate to the Back Plate with the Medium and Large Pulley Assemblies in between as shown below \ 0 0 Q 9 --t to. + '-I 9 8 /" (:.-""""'" ) "'" ',I -.\ 2 -..J. It ll: 6'f 6 x< ) -,.=:::=:> /O g

6 ST 4. Attach the 4 Hex. Pillars onto the bottom of the Housing Assembly as shown {JR. J. J,-...: Il.;!u CD 4xi 4 X( ) ==-a:::..-

7 6T Activity Overview This Kit is designed to allow students to explore pulley and compound pulley systems. Students can observe the velocity ratio, and measure the mechanical advantage and efficiency of a 2 and 3-pulley system. Useful Info and Data Pulley systems are simple machines, which have been used for centuries for lifting heavy loads. A considerable number of pulley sets or blocks that had been used to raise sails, were recovered when the Mary Rose was raised in 1982 after 440 years under water. Although crude by modern standards, they were very useful and highly developed compared to other machines of the time. Pulley systems are still in widespread use today in the form of hoists and lifting gear. Pulley Configurations and Formulae Single Pulley Velocity Ratio = 1 u 2 Pulley Velocity Ratio = 2 3 Pulley Velocity Ratio = 3 Effort Velocity Ratio = No. of Pulleys in System Mechanical Advantage = Effort Efficiency (%) = Mechanical Advantaae x 100 Velocity Ratio

8 7T B I I ---AD/d;;1;;'- I THE EQUIPMENT: The equipment consists of a pulley block in which there are 2 pulleys one larger, one smaller. Both pulleys are allowed to run freely in bearings. This double pulley block is fixed to a TASK miniframe; there is also a single "jockey" pulley block. A cord is used to link the pulleys in the chosen configuration. Measurements are made by adding a number of weights to form a known load. Weights are added incrementally on the "effort", until with a slight impulse, the load is lifted steadily and without stopping. The load is increased and the procedure is repeated. Basic method: 1) Set up the equipment as directed for a 2 pulley system 2) Add 100g to the load end (keep hold of the cord on the effort end!) 3) Add masses 10g at a time on the effort end until the load is pulled upward steadily and without stopping. 4) Record the effort mass 5) Repeat steps 3 and 4 with loads of 2009, 3009, 4009 and ) Reconfigure the pulleys to a 3 pulley system and repeat the procedure

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10 IS B AD/de 11/99 YOU WILL NEED THE FOLLOWING: eb A TASK Miniframe eb 2 Wei.Qht Sets 2x And from the TASK Simple and Compound Pulley Kit: A Double Pulley - - A Cord with Hook...>"'\ A Single "Jockey" Block Pulley Block Plate ii:::i If 1. Attach the Double Pulley Block onto the Miniframe at the very top as shown.. 11;;.r, e. ), "

11 28 2. Feed the Cord around the appropriate pulleys for a 2 or 3 pulley system followinq the diagrams below which show the path of the cord. 2 Pulley System 3 Pulley System 2x s -. 0 a. '\.-.t:. / NOW SEE YOUR TUTOR ABOUT HOW TO PROCEED. I