In order to use the device, it is necessary to know how and in what sequence the device of the theodolite 2–30 should be put into operation, how to do its calibration and adjustment. You must be able to recognize in the device its parts and the principle of operation for measuring angles both horizontally and vertically.
The general scheme of the main parts and axes of theodolite.
- for surveys of a topographical nature;
- tacheometric work, survey processes;
- surveying measurements;
- on construction sites for center jobs that do not require perfect accuracy.
Characteristic of the device
Tripod and optical plummet - serve to set theodolite above the point fixed on the ground.
Measurements of angular values are needed to determine the position of objects in space. Such manipulations are made for the triangulation network. The classic type of work is geodetic measurements for the construction of various structures.
The accuracy of the device, close to the ideal, is expressed in minutes, fractions of seconds. Theodolite has an optical and mechanical device for measuring angles, distances, magnetic azimuths. Devices are divided into types depending on accuracy, among which technical 2t30. Digital indexes in the name indicate accuracy, that is, the quadratic error in determining the angle at one time in seconds. The device theodolite 2t30 consists of nodes:
- Cremallera, diopter ring, cap with adjustable filament network screws;
- optical sight, vertical ring, pipe strut;
- screws for adjustment, fastening limb, alidade, pipes, lifting, pickup limb;
- level of the form of the cylinder, the basis of the cover, pipe, stand;
- elements, mirror surfaces.
Landmark compass is needed to measure magnetic azimuths and is installed in a groove located on the side cover of the theodolite's vertical circle.
It is equipped with a micrometer, it improves the accuracy of measurements. With the help of its elements, geometric leveling is done, the plummet allows you to work in a three-pillar system. The distance is possible to calculate on the leveling rod.
Level-cylinder moves the horizontal limb perpendicular to the line in the sheer state. It is a tube made of glass like an ampoule, its cut is an arc of a radius of 3.5 to 200 m. This container is filled, as a rule, with alcohol, ether, that is, it has easily mobile properties. It is sealed in a heated condition. Cooling creates a bubble. Zero take the point in the center of the scale of the ampoule.
Devices of this nature have levels in the form of a cylinder, a circle, they are different by the parameters of division, sensitivity, design.
The cylinder of the ampoule is decorated in a metal frame, it is with a setting screw, there are divisions outside the tube with a distance of 2 mm, a dot in the center is a zero point. Its axis is the line with regards to the level inside, at zero point.
Field of view of the reading microscope.
Round - an ampoule of glass, polished inside, with a certain roundness. Here the zero point is the center in the circle. The axis appears normal, laid through zero, it is perpendicular.
Zero location is made smoother contact levels. They consist of a level cylinder, above it there is a device with optics, transmitting the faces of the ends of a bubble to the lens. It is placed at zero when its opposite sides meet.
The level price is the angular index of the displacement of the bubble in one stroke. It can be in cylindrical 5-60, in round - 5-20.
Sensitivity is a noticeable smallest bubble movement, it is usually 0.1 stroke or 0.2 mm. Pipe elements - screws, optical parts, dimensional mesh. It houses the sighting, optical axis. The first connects the lens with the strands of the dimensional network. The eyepiece with the lens is connected to the second.Back to table of contents
Working condition: features
The tube must be adjusted to the eye, that is, rotate the eyepiece until the filaments become clear. Kremalyera regulated to clarity of purpose. The horizontal position is corrected by a screw for aiming, before that the alidade is fixed, vertically - by a screw, then fixed by one more screw.
The scheme of the main axes of theodolite.
The field of vision is the place surveyed by the pipe in stillness. Strokes, numbers fall into the field of view of the microscope, it is fixed with a diopter ring on the eye until it is illuminated.
A circle horizontally is a limb, there are degrees on the hour hand. On the circles there is a gradation of 1 °. There are 359 ° in horizontal, vertical has 0-75 ° and from 0 to - 75 °.
Alidada serves as a reference part, it is coaxial to the plane with gradation. A circle is vertically the same as a horizontal one; it measures inclined angles.
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The cylinder-level bubble is adjustable with bolts.
Features of the device:
- The axes.
- OO1 - vertically, the axis of rotation of the device.
- UU1 - in the level cylinder.
- WW1 - for a viewfinder, a lens and a dimensional network.
- VV1 - pipes.
They are correctly set as follows: UU1 ^ OO1, WW1 ^ VV1, VV1 ^ OO1 The limb stroke is a countable indicator, the accuracy is up to 0.5 ′. When the value in the circle vertically "-" is counted by the indicators of the row from the bottom with "-" (-4.0, from right to left). Magnetic azimuth is measured by the guide-compass, it is fixed on the side cover of the circle vertically. Screw arresting set the device to zero. The mirror shows the arrow, it is brought to the desired position. The adjustment of the arrow in a non-functional state is made with a compass screw.Back to table of contents
Verification scheme: a - level, b - sighting axis, c - horizontal axis.
For this there is a special case with sockets. When packing it, the screws are placed in the middle position, the pipe is laid horizontally, the moving parts are fixed, the screws for the lift are tightened to the stop. With the help of a tripod with an optical plummet, the device is placed on top of a point in space, that is, above the peak of the angle.
Its legs are hinged with headbands, the device is fixed on them with a screw. In a leg there is a case of a plumb with a thread. The tsentrir with optics is built in in a rack. Having centered, the base is moved on a tripod head, so the center in the network is combined with the point of space. If there is no plumber, then a plumb with a thread is used for this. The device is fixed to a tripod with a bolt, you can hang a plumb on it.Back to table of contents
The product of calibration of theodolite 2t30, adjustment
To work with the device you need to follow the rules. The vertical axis is vertical, and the reticle is vertical. Because of the transportation and transfer of the device, they are violated, so checking and adjusting (adjusting) need to be done often. They are executed in some order. For the working condition of the device, it is necessary to make a verification, as well as:
- Theodolite centering 2t30. The center of the horizontal plane is above the peak angle. This is done by a plumb with a thread, a plummet, the location of the tripod, moving the device on a tripod. Accuracy is permissible up to 3 mm for horizontal angles.
- Horizon. The scale of the horizontal circle is located in the plumb line. The level-cylinder is placed horizontally to the bolts for lifting, they are rotated together in different directions, the bubble is brought to the center of the cylinder. The cylindrical level is moved by 90 ° relative to the third bolt. It rotates, once again bring the bubble to zero point. This is done until the deviation is more than 1 stroke from the center. The error during operation is not more than half a stroke.
- Pipe preparation. The eyepiece rotates to the definition of the grid, the cremalier to the definition of the object. Parallax eliminate adjustment kremalyery.
Basic verification device
There are five verifications. The horizontal axis of the cylinder-theodolite level 2t30 is perpendicular to the axis along the vertical I-I1. Aliduda is set to position the axis of the tuned cylinder-level in parallel to the plane of the lifting bolts, which position the bubble at zero point. It is moved, and together with the cylinder 180 degrees.
- With a bubble in the null-point or with a deviation of no more than 1 division, verification is done. If not, the screws adjust it to half the error rate, the second half is removed with bolts for lifting. Lead axis vertically in the plumb position. The cylindrical level is placed in the direction of the adjusting bolts, the bubble is at zero. Alidade is rotated 90 °, the bubble is driven to the center by the third bolt. Make up to an error of less than one dash.
- Vizir (pipe axis) V-V1 must be positioned against the H-H1. The angle of error of the reticle from the perpendicular to the horizontal axis H-H1 is referred to as a collimation deviation. When checking out chart point M, it should be on a par with the axis of the pipe. Sight it, make the account (R) on a horizontal plane, the pipe is conducted through the zenith, sent to the point, again the countdown (L). If there is a collimation deviation, then: L - R ± 180 ° = 0. L and R - readout on the vertical plane on the left (CL) and on the right (KP). When deflected in the first hover, the sighting axis will be in the V-V ‘state, after the second - V1-V1 '. Then L - R ± 180 ° = 2 s. As a result, c = (L - R ± 180 °) / It is necessary that the collimation error does not exceed the accuracy of the readout element (1 ′). To avoid unacceptable deviations, alidade is placed on one of the accounts. Formulas: NR = R + c (with KP) or NL = L - with (with CL). Then the center of the network will move to the corner from. Bolted its center is combined with point M.
- H-H1 in perpendicular to I-I1. On the wall for 20-30 m choose point A, suggest the center of the axes. The pipe is placed horizontally, point a1 is marked, the center of the network is projected into it. When conducting a pipe through the zenith, they direct it to the same point, they also mark point a2. Items a1 and a2 must match or be in the bisector of the network.
- Network dash vertically in a parallel plane to I-I1. The center is guided by a vertical thread set at 5-10 m. When the pipe rotates, the line and the line coincide. All done.
- The centric axis is parallel to the vertical. The projection of the center is planned on a paper sheet, it is placed under the tripod. The locking bolt is loosened, the device is moved. The centric axis is parallel to the axis vertically.
Now everything is done.