It is a visual aid that allows the user to measure more precisely than could be done unaided when reading a uniformly divided straight or circular measurement scale. Calibration of measuring instruments on a coordinate measuring machine 129 figure 2. The unit we call a foot has been used since ancient times. To provide an overview of the spectrum of available for measurement and evaluation of workrelated psychosocial factors. Units of measurement and their standards, which is concerned with the establishment, reproduction, conservation and transfer of units of measurement and their standards. Anglemeasuring instruments may be classified into four types according to the measuring method used. The angle of the work part is first measured using an instrument such as bevel protractor. Add and subtract decimals and determine the tolerance range of given dimensions. Pattern approval requirements department of industry, science. With a need to make quality products which meet design specified tolerances, a large number of firms, research and development centers, and school and college laboratories use measuring instruments that have high accuracy and precision. To pass the pattern approval process, an instrument prototype must meet these. Eyepiece type instrument may cause strain on the operator.
Download various measuring instruments pdf latest instruments. To measure areas of your pdf document, select any of the following measurement types. Change the scale of measurement to match your documents specification. It includes divided scales like protractors, bevel gauges.
File installed on the computer system of the measuring instrument. Pdf instruments measuring the diseasespecific quality of. Scope this recommendation applies to length measuring instruments hereinafter called instruments that is to say instruments other than length measures which determine the length of a line, wire, cable, tape, piece of cloth, strip, sheet or any other developable piece. Use the following pieces of equipment to measure objects. To measure a distance, click anywhere on a pdf page to set a. Rulers, yardsticks and tapes determine the dimensions of an object. Measuring with an outside micrometer 01 inch using ball gauges with a micrometer. Design, manufacturing and testing of gauges of all kinds. Measuring instruments internal market, industry, entrepreneurship. Jul 06, 2017 how to maintain a precision measuring tool. In this course you will learn about decimals and tolerances as well as how to use the following tools. It refers to the art of reproducing and controlling dimensions expressed in thousandths of an inch or millimeter.
This guideline has been prepared to ensure that laboratories comply with both the measurement and traceability requirements of elot en isoiec 17025 and the relevant requirements for calibration and testing equipment set out in iso 10012. Measuring instruments the device used for comparing the unknown quantity with the unit of measurement or standard quantity is called a measuring instrument. The term precision measurement is applied to the measurement field beyond the scope of line graduated, non precision measuring instruments, such as the rule and scale. Classification, absolute and secondary instruments, indicating instruments.
Precision measuring and gaging od1642 lesson 1task 1 between two mating parts when certain allowances are designed in them. Types and use of precision measuring instruments bright hub. The laboratory shall also ensure that it has the staff resources needed. Twelveinch scale sixinch dial caliper outside micrometer 01 inch ball gauges once you complete a topic, a skill check is available for you to demonstrate what you have read and practiced. These instruments are most widely used in engineering practice because they are simple and inexpensive. Precision measuring instruments wiki odesie by tech transfer. An allowance is the total difference between the size of a shaft and the hole in the part that fits over it. Pdf available instruments for measurement of psychosocial. Mv video based metrology systems are easytouse, general purpose, noncontact measurement systems with zoom optics. Measuring instruments for large dimensions product category. Measuring instrument definition of measuring instrument by. Absolute instruments gives the quantity to be measured in term of physical constant of the instrument. The static characteristics of an instrument are, in general, considered for instruments which are used to measure an unvarying process condition. As software controlled devices are always electronic, it is also necessary.
Upload your pdf, cad or image file to start measuring. It enables accurate measurement of the distance and angle between two points on a page. Select the perimeter tool to measure a set of distances between multiple points. Face standard angular measuring devices include angle gauges and sine bars. Media in category measuring instruments dimension the following 147 files are in this category, out of 147 total. The least count of a measuring instrument is the smallest change in the measured quantity that can be. Then, the work part is clamped to the sine bar and set on top of a. This recommendation does not apply to measuring devices fitted on motor. Classification of measuring instruments electrical measurements.
The first group includes devices that compare the angle to be measured against a fixed gage, such as an angle gage for angles 1 to 180, try square usually for a 90 angle, tapered plug gage, or template. All the static performance characteristics are obtained by one form or another of a process called calibration. Measurement devices come in all shapes, sizes and types. Enginemen need measuring instruments to determine what parts are worn and need to be repaired or replaced. Instruments measuring the diseasespecific quality of life of family carers of people with neurodegenerative diseases. Guide on evaluating purely digital selfservice devices for direct sales to the public. As in linear measurement, they can be categorized in two groups. One can fit a straight line through the output values obtained from such instruments that exhibit linearity. Anglemeasuring instrument article about anglemeasuring. With this method, you do not have to reset the system to zero after turning it off and then turning it on. It is necessary to apply flat mirror and flat mirror interferometer, because it is not possible to avoid movements in different directions. Certificates for specific categories of measuring instruments or modules on the basis of.
Passive sensors do not add energy as part of the measurement process but may remove energy in their operation. Projection type instruments occupy large space and they are expensive. One example of a passive sensor is a thermocouple, which converts a physical temperature into a voltage signal. The examination of the design principles of digital instruments only with. Measuring instruments directive 201432eu, common application. The most natural way to measure length is to compare it to some part of the body, and for centuries, people did just that. Our pressure measuring instruments are available in the measuring ranges 0 0.
Metrology instruments corning fairport formerly known as corning tropel manufactures a complete line of noncontact metrology instruments that measure surface form for flatness, parallelism, height, depth, surface finish, roughness or thickness, with submicron to nanometer accuracy in just seconds. Large sizes in mechanical engineering mean dimensions in excess of 500 mm. Guideline for selecting outcome measurement instruments for. Measuring unknown angles using sine bar sine bar can also be used to measure unknown angles to a high degree of precision. Select the distance tool to measure the distance between two points. Examples of measurement process metadata include format of the. Contact angle measuring instrument dsa100 processor tensiometer k100 with care to accuracy. Definitions used in electrical measuring instruments. Z height is measured by moving vertically to maintain focus. They have their own built in illuminating device which tends to heat the instrument.
The measurements are done with respect to two faces of the measuring instruments. Adobe pdf files are compact and can be shared, viewed, navigated, and printed exactly. The second category of angular measuring instruments is called face standard instruments. Jul 20, 2014 in this post we will discuss about classification of electrical instruments. Certificate, in a protected pdf format, to the biml for registration, either. Precision obtained in such instruments is more than the precision obtained in line standard angular measuring devices. Unit 6 angular measuring devices angular measuring devices. Apr 02, 2017 because of these diverse geometrical forms, different types of methods, equipment and instruments are available to measure angles in common angular units of degree, minute and second. It is the exact value or the perfectly correct value in any measuring scheme. Most practical instruments are designed to exhibit linearity because it maximizes the convenience of it use. To ensure a coherent application of the measuring instruments directives, the commission and welmec european cooperation in legal. Classification of instruments electrical instruments may be divided into two categories, that are. These instruments converts the energy of the measured quantity directly into energy that actuates the instrument and the value of the unknown quantity is measured or displayed or recorded directly. Types of precision measuring instruments used in industry.
Classification of digital measuring instruments springerlink. The set of criteria defined for the instruments, which are used to measure the quantities which are slowly varying with time or mostly constant, i. We systematically searched the literatureinternet to identify and describe. A highly stable mechanical design and precision linear bearings achieve superb performance. Grids, guides, and measurements in pdfs, adobe acrobat. Using a leastsquare minimization scheme is the most accepted method to fit a straight line. Quick guide to precision measuring instruments 4 quick guide to precision measuring instruments absolute linear encoder mitutoyos technology has realized the absolute position method absolute method. Pressure gauges assess the air or water pressure in a closed system. To maintain the accuracy and reliability of a precision measuring tool, one has to do. Established standard objects and events are used as units, and the measurement results in a given number for the relationship between the item under study and the referenced unit of measurement. Some commonly used face standard angular measuring devices are. Besides various measurement procedures like those that apply large internal or external micrometers with twopoint contact, tape rules wrapping round the outside diameter, vbases, rotating measuring disks rollingcontact and optical systems triangulation with theodolites.
Classification of electrical instruments electrical tutorials. In physics and engineering, measurement is the activity of comparing physical quantities of realworld objects and events. Measuring instruments are used to check tolerances and specifications during inspections and repairs of internal combustion engines and auxiliary equipment. X and y dimensions are measured by moving the stage horizontally. Wika offers a complete range of electronic pressure measuring instruments. Metrology instruments advanced analytic and metrology. Methods of measurement based on agreed units and standards. Cooper, modern electronic instrumentation and measurement techniques prentice hall, 1994. Measuring instruments guidance documents internal market. The purpose of this course is to introduce you to precision measuring tools. A classification schematic of digital instruments fig.
472 1417 797 1389 596 1001 32 267 752 942 832 518 695 978 1394 669 210 1605 321 957 401 1252 13 837 1069 1315 58 413 534 364 1339