Terms of Service Mechanical Comparators In mechanical comparators, the required magnification is obtained by using mechanical linkages, levers, gearing and other mechanical devices. Advantages of Mechanical Comparators Mechanical comparators are usually cheaper when compared to other amplifying devices. Mechanical comparators do not require any external sources such as electricity or air and as such the variations in outside supplies do not affect the accuracy. Usually the mechanical comparators have linear scale.
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Zeiss Ultra Optimeter: The optical system setup of this instrument involved a double reflection of light. Thus obtaining a higher degree of magnification and it is considered to be a highly sensitive comparator. The lamp sends the light rays to the green filter, which filters all but green light, which is less fatiguing to the eye.
The green light then passes to a condenser via an index mark projects it on to a movable mirror M1, where it is reflected another fixed mirror M2, and then back again to the first movable mirror.
Zeiss Ultra-optimeter The second objective lens focuses the reflected beam from the first mirror onto a transparent graticule that has a precise scale that is viewed by the eyepiece. The special end of the contact plunger rests against the outer end of the first moving mirror so that the mirror is tilted by vertical movement of the plunger. The sensitivity of this instrument requires special precautions in its operation to avoid temperature effects. Zeiss Optotest Comparator: This is the commercial measuring instrument.
It utilises a plunger titled mirror, objective lens, prism and observing eye-piece to provide a high degree of magnification. The mirror is mounted on a knife-edge and it can be tilted about the fulcrum by any linear vertical movement of the contact plunger. In the local plane of the eye-piece, a fine reference line, the index is provided and the system of lenses is so arranged that the image of the scale is projected in the same focal plane.
Thus with the movement of the scale, the image can be measured with reference to the fixed-line. The division of a scale image opposite the index line shows the amount of movement of a contact plunger. The image of the scale and the index line can be viewed through a projection system. Newall OMS Horizontal Optimeter: This comparator is designed for very high magnification and it can measure very accurately with great precision in a horizontal direction. It is widely used to measure the internal and external dimensions of cylindrical gauges, screw gauges and thickness gauges.
The instrument consists of a cast iron base with three levelling screws and a spirit level for setting instrument horizontal. Two brackets are mounted on a transverse bar carried through the base. The brackets are kept in alignment by a keyway and a spline and carry an optical measuring head and a tailstock respectively.
The transverse bar is spiral grooved to allow easy and quick lengthwise adjustment of the bracket. For various works, there are other attachments. Interchangeable heavy and light duty contact arms are provided for internal measuring and a centre cradle for male cylindrical work. Eden-Rolt Millionth Comparator: This comparator utilises both mechanical and optical magnification and thus is a highly sensitive one.
The setup is shown below: The mechanical amplifying device utilises parallel strip support, consisting of a fixed and a moving block connected together by parallel thin strips. Both the fixed and movable strips are connected to a pointer arm carrying web at the other and by two-pointer strips. In between of a fixed anvil and movable measuring block, a reference gauge is placed.
The slight movement or moving block through pointer strip causes the pointer arm to be deflected. The web at the end of the pointer arm is not viewed directly but it is projected through an optical system on the scale. Advantages of Optical Comparator Following are the advantages of optical comparator: High accuracy will be achieved as it has very few moving parts. Less weight than other comparators because of fewer parts. The parallax error will be avoided. Due to the high magnification, very suitable for accurate measurement can be obtained.
Disadvantages of Optical Comparator Following are the disadvantages of optical comparator: A separate power source is required. It is suitable to use in a dark room only. Optical instruments are expensive. Applications of Optical Comparator Following are the applications of optical comparator: Optical comparators are widely used for complex-shaped stampings, cams, gears, threads, and compare to measured contour models.
It is commonly used for measurement of optical devices. Optical comparators are widely used in the aviation and aerospace industry. The optical comparator is also useful in making of clocks and watches.
An Optical comparator is commonly used in electronics, instrumentation industry and research institutes. The Optical Comparator is also used in major machinery manufacturing and detection of metering stations at all levels and etc. If you like this article please share with your friends. Subscribe to our newsletter to get notification of our new posts. Email Address.
Optical Comparator: Types, Working, Advantages and More
Kiktilar This utilises a plunger tilted mirror, objective lens, prism and observing eye-piece to provide a high degree of magnification. Vernier Height Gauge Procedure: The amplified mechanical movement is further amplified by a simple optical system involving the projection of an image. Eden Rolt Millionth Comparator. We will need more information to help you.
Dailrajas Introduction milliotnh meter 2. The slight movement of moving block through pointer strip causes the pointer arm to be deflected as shown in Fig. I redshirted my daughter so she will start kindergarten at 6. The eye placed near the eye-piece views the image of a small scale engraved on glass after reflection from the plunger actuated mirror and the prism in the plan view in Fig. Two brackets are mounted on a transverse bar carried through the base.
eden rolt millionth comparators?