The implementation of most types of construction and installation works is impossible without the use of a special tool - an angle meter. As can already be judged by the name, this device is used to measure the angles of structures. The most popular at the moment are mechanical tools of this variety. Such goniometers are inexpensive, it is not difficult to use them, and measurements with their use can be made quite accurate.

Tool history

The mechanical protractor was invented a very long time ago. Along with the ruler, this is one of the oldest tools on earth. Scientists believe that he first appeared in Egypt and Babylon. After all, the construction of such grandiose structures as, for example, the pyramids, without a goniometer would have been simply impossible.

The design of this simple device has not changed much over the past centuries. Modern goniometers look exactly the same as those used by the ancient engineers of Egypt. The only thing in our time for the manufacture of such tools are other materials. Of course, the scope of modern goniometers is much wider.

Intended classification

There are many types of this popular tool. Goniometers are classified mainly for their intended purpose. Modern manufacturers produce the following options for this tool:

Construction.  Tools of this group are usually used for marking or installation operations. Mechanical building protractor can also be used in the development of drawings of projects of buildings and structures.

Carpentry Such tools are simply indispensable when performing various kinds of work with wooden blanks.

Mountain.  Used in surveying surveys.

Nautical.  Used to determine geographic latitude.

Locksmiths.  Such tools are used when performing work of the corresponding specialization. Mechanical bench goniometer usually has a rather high degree

Training.  These tools are used by students in the classroom and when doing homework.

Artillery.  This variety of tools is also highly accurate. Goniometers of this type are used when installing artillery guns.

Universal.  This can be used to measure angles when performing a variety of jobs.

Types of use

All mechanical tools existing on the market today can also be divided into groups according to such characteristics as size. In addition, such devices are classified by their field of application. A modern mechanical angle meter can be used:

For measuring external angles. Such models are marked with the letters UM.

For measuring internal angles (UN).

Design features

The unit of measurement of any angle, as you know, is, degree - 1/360 of the diameter of the circle. He is the step of the goniometer. Degrees, in turn, are divided into minutes and seconds. A common design element of all instruments of this type is the base in the form of a movable arc, on which a scale with degrees and minutes is applied. The latter is movably fixed on a special ruler, which serves as a starting point for measurement. Very often, the design of such tools instead of a ruler includes a square. It is fixed on a support level. It is possible to fix the obtained measurement result in such devices using a special screw.

Mechanical pendulum protractors additionally have a special structural element that assumes a vertical position when the angle of inclination of the measured part changes. Such tools are more convenient to use than conventional ones. They are used most often when working with dimensional products. For example, with their help, the actual angles of arrangement of nodes and mechanisms of agricultural machinery are measured.

Goniometers are most often made of tool steel. This material is durable and resistant to damage. The steel angle gauge is mechanical for a very long time. In some cases, tools of this variety can also be made of wood or plastic. Such models are most often used when performing various kinds of repair work indoors (for example, when installing wall panels or Sometimes devices of this type are also made of light aluminum.

Goniometer with Vernier

This is one of the most convenient Nonius called an auxiliary scale installed on the goniometer. This small additional element is fixed above the upper edge of the arcuate base and remains stationary during operation. It serves to more accurately determine the number of fractions of division on the main scale. The principle of the vernier is based on the fact that the human eye much more accurately notices the coincidence of divisions than the location of one of them between the others. A mechanical goniometer, supplemented with such an element, is, of course, much more convenient in operation than a regular one. In addition, the measurements themselves with its use can be made much better.

Instructions for use

The question of how to measure angles with a mechanical goniometer is quite simple. Using such a device, of course, is more difficult than an electronic option. However, you can still learn how to work it quite quickly. Measurements using mechanical devices are made by selecting various combinations of the position of their elements. For example, the external angles when using the universal tool of Semenov are checked as follows:

The square is pressed to one side of the corner of the product.

The scale of the arcuate base is applied to another.

Carefully check the junction of the tool and the sides of the corner of the product for any gaps.

Screw the tool to the item being measured.

They look at what value on the scale coincides with the edge of the square.

It is even easier to measure the angle between the converging or diverging opposite sides of the workpiece. In this case, you can also use the goniometer mechanical design Semenov. For measurement, one of the sides is simply assigned a horizontal bar of the tool on which the square is fixed, and to the other - the scale of the arcuate base.

- a mechanical or electronic device designed to accurately determine the angles between surfaces, structural elements, parts or components of equipment, as well as between remote objects. Angles are measured in degrees using a special scale with a mechanical pointer, vernier or electronic display (depending on the type of device).

Design of goniometers

In the simplest version, the goniometer: electronic, mechanical consists of two measuring surfaces (rulers) fixed on one axis. Being mobile, they are freely positioned at an angle relative to each other. To determine the value of the angle, depending on the type of device, a ruler, ruler, circular dial, electronic reading device or other additions are used.

Some types of goniometers have fixed angles, such as in carpentry. Also, in individual devices, the following nodes can be used:

Types of goniometers and their purpose

Of the most commonly used, we note the following types of devices:

• Building goniometer - used in marking, installation and design work. It has various sizes and methods for measuring angles.
• Joiner goniometers - used to approximate the determination of the angle, often equipped with a scale with fixed angles.
• Metalwork goniometers are used for measurements with high accuracy, often equipped with a vernier scale.
• Surveyors or mountain goniometers - allow you to measure even at a considerable distance.

There are also used and specialized goniometers, the purpose of which is quite clear by their name - astronomical, nautical and artillery.

How to use the device

To obtain accurate values, regular calibration of the goniometers is necessary, checking their compliance with the reference values. The measurement process itself is as simple as possible:

• The base or one of the rulers is tightly applied to one of the surfaces.
• An arc scale or second ruler is applied to the second surface.
• The position of the rulers is fixed with a screw.
• The angle is determined by the coincidence of the scale with the edge of the ruler.
• In the presence of a nonius, seconds of the angle are determined.

The above describes the procedure for using a mechanical protractor - a simple universal device with which you can measure internal and external angles. Using an electronic device is even simpler - you just have to fix the measuring surfaces and get readings from the electronic display.

Goniometer - current GOSTs

The main current state standard for a universal goniometer, GOST 8378-83. The technical conditions of measuring instruments with a vernier scale are regulated by GOST 5378-88. For specialized devices, their own standards have been developed, in particular for optical goniometers - GOST 11197-73.

The goniometer is an accurate instrument designed to measure the angles between two surfaces or their inclination relative to the horizon. The results are expressed in degrees. Goniometers have a similar design with a building or carpentry corner, but they can show not only an angle of 90 degrees, but also be adjustable.

The simplest design of the protractor

The design of the protractor in its simplest form consists of two plates (rulers). They are fixed together on one side, being fixed with the help of an axis, which allows changing the angle between them. On the surface of the instrument there is a scale expressed in degrees. It can be ruled or rounded. There are both fully movable goniometers, and with fixed measurements. The latter are used in cases where it is only necessary to measure the most important angles - 90, 45 and 30 degrees. Such a tool is more in the category of templates.

In which industries is the goniometer used

This device is widely used in construction. It is used by joiners, carpenters and installers. With it, you can set the plane perfectly evenly before fixing. The vast majority of objects that are used in everyday life and in industrial facilities have angles of 90 degrees. It is an established international standard that provides maximum convenience. In addition, non-compliance with the angle of 90 degrees in the construction of vertical elements increases the load on the structure.

For example: Due to the fact that the corners of the buildings are measured accurately, when installing the corner bath, there is no gap under the wall and when hanging cabinets and shelves everything looks even. There are thousands more examples that allow you to visualize the benefits of accurately observing angles. The use of goniometers allows for the accurate transfer of the parameters displayed in the drawing to a real object.

Also, goniometers are used in the construction of routes, in military affairs, geometry and astronomy. Due to the demand for this instrument, its design has been adapted for various measurement purposes.

Goniometers can be divided into types:

• Building.
• Locksmith.
• Carpentry.
• Mountain.
• Astronomical.
• Nautical.
• Artillery.

Building goniometer is the most common. It is used to control the level of walls, foundations and other structures. Such devices are quite overall. The length of each measuring part is usually at least 50 cm.

Locksmith  have high accuracy. They are quite compact, while they have a fairly sensitive adjustment, allowing measurements to be made with a fraction of a degree displayed. This is necessary because the slightest deviations from the norm are unacceptable. With such goniometers, you can safely measure the parameters of parts that will be used in rotational mechanisms.

Carpentry  goniometers are characterized by low measurement accuracy. They are used in woodworking, when the exact observance of angles and fractions of degrees does not matter. Such an instrument belongs to the low price category. Often the adjustment mechanisms have backlash, which also leads to errors. Despite this, a similar type of goniometers is quite acceptable for the fulfillment of the goals for which it is intended.

Mountain  goniometers, unlike previous varieties of these instruments, are not used for direct contact with measured surfaces. This tool allows you to visually determine the vertical and horizontal angles in the spaces of mines and mine workings. This equipment is inaccurate. Now it is practically not used in connection with the advent of more high-precision electronic equipment, such as total stations, etc.

Astronomical  are the most accurate. They are used to measure the angle between the surface of the earth and points in the sky. With their help, the trajectory of the motion of celestial bodies is calculated, the speed of their movement is determined, and the size of the object is estimated. Such devices are often integrated into telescopes, which broadens the range of their measurements, since the object of study can be not only objects visible in the sky, but also distant stars and planets.

Nautical goniometers are also called navigation. With their help, the geographical latitude is determined using a special table. These devices operate on the principle that a celestial body (sun, moon or stars) on a certain day and time is above the horizon at a special angle relative to geographical latitude. Thus, using this device and the table, the observer can determine the latitude at which he is at the moment. This device has been widely used by sailors in the past, but with the development of satellite technology, its use has faded into the background. Despite this, such goniometers are on board many ships, because in the event of a failure of electronic equipment, the use of a hand-held device will be the only way to obtain the exact coordinates of the vessel.

Artillery goniometer  It is used to mount artillery guns and to correct salvo fire. The use of such a tool allows precise aiming and changes in the direction of the shot after preliminary targeting

Types of goniometers according to the principle of measurement

According to the principle of measurements, goniometers are divided into the following types:

• Mechanical.
• Pendulum.
• Optical
• Laser
• Electronic.

Mechanical  goniometer refers to contact devices. In order to carry out the measurement, it is necessary to attach both surfaces of the tool to those objects, the angle between which you need to measure. The device has a special scale that allows you to determine which angle between the sides of the tool is obtained. Since the sides are closely adjacent to the measured surfaces, their angle will accordingly be equal to the scale.

Pendulum  the goniometer outwardly resembles a clock. A marking corresponding to the corners is marked on the round dial of the instrument. The arrow of such a goniometer always stands perfectly upright, regardless of how directly the device itself is bent. At the bottom of the device there is a small line. It is applied to the surface that needs to be measured, after which you need to look at the indicator of the formed angle between the “0” mark on the dial and the arrow. With the help of such a device, it is possible to measure the level of inclination of one surface.

Optic The goniometer has an unusual shape for this equipment. You can recognize optical goniometers by means of an eye that acts as a magnifier. Optical instruments have a measuring range of 360 degrees. They are very accurate, since many marks are marked on the scale, not only in degrees, but also in their shares. In this regard, it is difficult to visually determine which indicator the arrow points to. Opticals have a magnifying magnifier. Thanks to it, it is much easier to count the marks indicated by the arrow on the scale.

Laser  The protractor has in its design two laser beams traveling on the surface, between which it is necessary to measure the angle. The angle between the points is measured visually or using a computing electronic element, which is integrated into the design of the device. Such a device works well at night, as well as indoors. In daylight, the laser beam is almost invisible.

Electronic  or digital goniometers similar in principle to mechanical ones. Except that they have a dial in the form of an LCD display, which displays the indicator in numbers. This is a very accurate equipment that allows you to determine tenths of degrees. To power such a device, a conventional finger-type device is used. Such tools are used by builders and installers.

How to work with contact goniometers

Contact type goniometers are the most common and inexpensive. They are used everywhere. To take a measurement, you must attach the tool to the corner that you want to measure. One ruler of the protractor is pressed to one surface, and the second to another. If necessary, the device must be corrected by increasing or decreasing the angle between its sides. The measurement results are displayed on a mechanical or electronic scale. For the data to be as accurate as possible, it is necessary that the surfaces at the points of contact are flat. If, for example, the angle between the floor and the wall is measured, it is necessary that there are no layers on them in the form of adhering lumps of mortar or glue. Such a grain under one of the rulers will violate the received data by several degrees.

How to choose a goniometer

When choosing, you should pay attention to the material. If it is made of very thin metal, then you should not take such a tool. Over time, it deforms, so the accuracy of the measurements will be impaired. For a cheaper range, the scale is often painted. As a result, over time, the paint begins to peel off. After that, it is impossible to determine how many degrees the tool shows.

The cost of the goniometer depends not only on its design features, but also on accuracy. The higher the accuracy, the less backlash on the axis of adjustment, which requires more costly production. For carpentry or low-rise construction, it is quite possible to do with tools of a lower category, but for the manufacture of critical parts, you need accurate equipment.

In modern construction, a lot of attention is paid to the so-called space geometry - in the room everything should be perfectly even! This is explained by the fact that most interior items require even walls and corners for their installation. Take, for example, a corner bath - what happens if the tiler-tiling does not withstand an angle of 90 помещении in this room? The gap between the wall and the bathroom is guaranteed, and masking it is an additional waste of time and money. In this article, together with the stroisovety.org website, we will deal with a tool such as a goniometer, get familiar with its varieties and learn how to use it, because it is this tool that allows you to control the correct angles within the required value.

How to choose a goniometer

Goniometer: varieties and features of their designs

All goniometers, which are somehow used in the modern world, can be divided according to purpose into seven types. Each of them has its own, strictly individual specialization and, accordingly, a special design.

And these are only the main types of goniometer, the most common in our world. In addition to them, there are many other, less used, but at the same time indispensable in their field such devices.

Types of goniometer

Differences of the protractor by device type and measurement principle

By their design and the principle of measurements, all existing goniometers can be divided into six types - this is an electronic goniometer, laser, optical, pendulum, mechanical and a goniometer of fixed angles. Let's consider them a little more in detail.

In addition to the above types of goniometers, there is the so-called universal goniometer - it is designed for everyday monitoring of work and does not differ much in accuracy. And among the universal tool of this type, quite often you can find combined varieties that combine several methods of measuring angles - quite common designs of this type are laser-mechanical goniometers or electronic. The latter can be combined with almost all types of goniometers.

Universal photo goniometer

How to use the goniometer: measurement principle

Angle measurement has a simple principle, especially when it comes to modern devices, stuffed with electronics. If we talk about them, then all that is needed to measure the angles is to set the tool rails in the right position or direct its rays to the necessary points. Next up is the electronics - it is she who performs all the necessary calculations.

Mechanical, optical and similar goniometers are another matter - here you will have to learn to perform calculations and use a measuring scale. As a rule, a protractor with a vernier scale causes particular difficulty. In fact, if you look, there is nothing complicated in such measurements. We set the goniometer guides in the desired position and move our eyes along the usual scale until we hit zero on the nonius - this is how we get the degrees of the angle. To calculate the angle to minutes, we move from zero nonius until we find a division that clearly coincides with the division of the main scale - this figure will show the desired number of minutes.

How to use a photo goniometer

Measurements are also not much more complicated with the help of an optical goniometer - two parts of the instrument are installed in the necessary position, after which, looking at the scale in the moving optics, the measured angle is calculated.

Like it or not, a goniometer in construction is by no means a useless tool - if you look at the scope of its application, you can find out that it will become an indispensable tool for tilers, drywall workers, roofers, masons, and many other craftsmen whose work is connected with the construction of planes. For these reasons, there are a huge number of goniometers for various purposes.

We already know how to use a protractor of the simplest form from school, but the types, destinations and designs of this tool are much larger, sometimes the principle of its operation is not even entirely clear, although the task is the same - measure the angle of inclination in a plane or space. We will try to eliminate the gaps in the course of reading this article.

Goniometer - device and purpose

This tool, it is not difficult to guess, exists for measuring angles, and this can be not only planar images, as in school notebooks or production drawings, but also the tilt of the parts with respect to each other in any structures. It is possible to measure performance even in remote objects, for which the optical version of the device is successfully used.

We are used to the fact that for reliability it is better to sense what we are measuring, that is, the device intended for the operation is applied to the surface under study, but the contact method, although prevailing, is not the only one. The optical method allows you to calculate angles, being relatively far from the studied objects. The result of measurements is always presented in degrees that are familiar to us, which you have to read yourself or observe on displays that are possessed, for example, by a digital goniometer. The instruments differ in the scale with which to take readings.

It can be ruled, and also include an additional circular component, the orientation of which is facilitated by the arrow. The scale can be represented by a nonius, we will consider this separate type of devices in more detail below, and the most advanced can be considered electronic.

The device of the simplest angle meter is quite primitive: two rulers with scales that are set along the corner and give the desired value. Others are more intricate. Before work, the measurer fixes some corners of the device with a known value, a kind of tuning tool. But, for example, the joiner's protractor is already sold with a tightly fixed and measured angle, which is convenient for a quick assessment of the slope of the surface with which the master works.

Types of tools for measuring angles

The most relevant for us is the construction goniometer. Without him and his faithful companions (plumb bob), not a single site would have cost. All equipment is installed with a clear assessment of the terrain in three dimensions, all installation work, any markup - all this requires proper orientation in space, and the human eye is far from perfect, so even the horizontal plane is hard to weigh, and what can we say about the angles.

The metalworker's and joiner's goniometer always accompany specialists, because their products then serve in various areas of human activity, and the slightest deviations in the axes or corners can sometimes cost a living. To compile reliable topographic schemes, it is also impossible to use our natural optical device, in fact, how impossible it is for them to evaluate subtle medical indicators. Therefore, a topographer and orthopedist cannot work without such an instrument.

The romantic profession of an astronomer also cannot do without such an instrument. Schoolchildren master the first basics of geometry with such a device in their hands, more often they are ordinary squares with already fixed angles of a known size. Engineer, miner, seafarer - professions that use almost the entire range of possible instruments for measuring angles. In each area, such data is needed with varying degrees of accuracy and reliability. Increasingly, high-tech laser goniometer finds application, this is especially true in the military industry (sights).

If the scope of application is almost limitless, then the classification of the instrument by device is somewhat more modest: optics, mechanics, laser and electronics. Already inside this classification, you can find many other parameters that affect the choice of the customer, for example, permissible errors. Also affect the price of the product mobility, functionality, size of the device itself, its equipment.

Mechanical angle meter - what is it?

For now, a mechanical device is considered habitual and affordable. Such a goniometer is universal, because it allows you to fit it to almost any surface and take readings of the external and internal angles. It happens optical type and vernier. The second is more common and convenient for contact measurement. Nonius is an auxiliary refinement scale that is combined with the main one and increases the accuracy of the value by orders of magnitude. Its role may be familiar to you from handling the vernier caliper and other mechanical measuring instruments.

When buying a device, it is important to ask what regulatory document (standard) the product was manufactured because accuracy will be a critical parameter, and if there is no regulatory document to verify and configure it, then your measurements may be far from the truth. therefore it is best to avoid Chinese manufacturers who rarely take calibration very seriously, but are cheaper than any Russian or European counterparts.

Mechanical types of devices have the most intricate structure. The vernier type includes the following nodes: a housing to which a disk is attached with a nut, a base with a main scale and a vernier, and there is also a ruler and a shank that moves along it in the process of fixing the value of the angles. The optical view consists of a case in which a disk with a scale is located, a fixed ruler is attached to it, and a magnifying glass, a movable ruler and its lever are mounted on the disk. Under the disc there is a plate with a pointer, which is visible through the eyepiece. This whole system is set in motion, then it is fixed in the selected place, and a reading is taken through the magnifying glass.

How to use the goniometer - an approximate principle of action

The more automated the device, the less we need to do work. For example, an electronic goniometer only needs to fix the rulers in the desired position and displays the result on the display. Optics will already require installation of the instrument on a flat surface in order to avoid fluctuations relative to the horizon. And the mechanics will also require a minimal understanding of the device itself in order to find a way to correctly take readings. Therefore, we will analyze the most capricious cases that we can expect.

Vernier device

A device is applied to the desired angle on the plane, its ruler and case must coincide with the sides of the angle. Now we count the degrees on the main scale until we reach the zero level on the nonius, so find the degrees. Now we move along the vernier scale until we find a division that coincides with the division of the main scale, as if extending it into one straight line. So minutes are defined. Depending on the accuracy of the instrument, the values \u200b\u200bof the scales may vary, study the passport of your instrument.

Optical instrument

The movable ruler should be moved so that it and its stationary partner form the desired angle. Then the clamping ring is fixed. Now it should be remembered that the disk and the magnifying glass of this mechanism are dependent in their position on the moving ruler, which means they make up a kind of indicator of the desired value. Through the magnifying glass, you can observe the markings on the disk, which are correlated with the mark on the plate, and the readings of the device are calculated.