SU59000A1 - Optical instrument for checking the position of the engine cylinders and the parallelism of the crank necks and the axis of the crankshaft - Google Patents

Description

Inspection of the installation of engine cylinders during ship repair is usually performed by a string pulled along the axles of the cylinders, which represents painstaking and time-consuming work consisting of linear measurements and measurements of angles (small or close to 90 °) between the geometric elements of the parts significant distance from each other. To facilitate and refine this work, an optical instrument is proposed for checking the position of the engine cylinders with both the crankshaft removed and the crankshaft laid (the piston and cover are assumed to be removed). According to the invention, the instrument's telescope is obliquely mounted on a crossmember, which is superimposed on the upper end of the cylinder. The crossbar is equipped with adjustable stops at the ends, as well as a ruler with divisions.

In FIG. 1 and 2 show the installation of the device on the cylinder of a steam engine; FIG. 3, 4-consecutive position of the device when checking the perpendicularity of the cylinder axis to the axis of the engine crankshaft; FIG. 5 illustrates the measurement process using this instrument.

The proposed optical device consists of a cross member 1 (Fig. 1) supported by stops 2 on the upper end of the cylinder and stops 3 on its inner surface. The cross bar is equipped with a telescope 4 with a cross of threads and a scale of 5 facing down. The stops 2 and 3 can be mounted on the crossbar 1 and fixed in any position, depending on the diameter of the cylinder being inspected. The axis of the pipe 4 is slightly inclined to the axis of the cylinder and is shown in the drawing set in the plane of the measurements to be made (in the plane of the drawing).

To measure the distance L from the axis of the cylinder from parallel to the last, a ruler 6 is placed perpendicular to the divisions, in which two readings are made by means of pipe 4 at two instrument positions that are symmetrical with respect to the axis of the cylinder, i.e. t at the position of the device according to FIG. 1, and another count / 2 - at the position of the device according to FIG. 2

(turning the device through 180 °). Moreover, due to the symmetry of the two positions of the device (Fig. 5) relative to the axis of the cylinder, the optical axis of the pipe 4 intersects the ruler 6 successively at two points, also symmetrical about the same axis and located from the latter at some distance X, then:

/ / - - X /.) A to X,

where we get the desired distance

/ 1 -f k L

To check the perpendicularity of the cylinder axis to the crankshaft axis of the engine, a flat mirror 7 is installed on the crank neck parallel to it (Fig. 3), in which the scale 5 is reflected. Therefore, the reflection, using pipe 4, is read first at the position of the device in FIG. 3 (counting a,), and then at the position in FIG. 4 (counting a,), i.e., after turning the instrument through 180 °. The difference of the samples, divided by the quadruple distance H of the device from the mirror 7, gives the tangent of the desired angle deviated a from the perpendicular;

ffl "9

ta7 -liL

If there are doubts about the parallelism of the axes of the crank neck and shaft, then the check in FIG. 3 and 4 are repeated at the lower (and, if necessary, with an average) position of the crank. Sine results, determine deviations from parallelism. The possible jvOHycHocTb crank neck is taken into account by measuring it in the usual way.

In the case of a retracted crankshaft, the perpendicularity of the axis of the next to the axis of the cylinder is checked by installing mirror 7 parallel to the axis of the frame bearings or parallel to some other direction, the principle is basic. In the same way, distances can be checked. crank joints and crankshaft axis from the cylinder axis, the position of the connecting rod in the assembly of motion, the perpendicularity of the upper end of the cylinder to the axis of the latter, etc.

The required deviation of the crosshead engine parallels from the position parallel to the cylinder axis can be checked in two ways: by measuring the distances of the cylinder axis from the parallel at the top and bottom of the latter in FIG. 1 and 2 or by measuring the angle as in FIG. 3 and 4, with the mirror 7 being installed perpendicularly to the "Parallels" (by means of a calibration square).

To be able to read along the ruler 6 (fig. 1) of a millimeter fraction, the device is equipped with micrometer screws not shown in the drawing, jazz and move the tube 4 within a small range to match the last point of intersection of the filaments with the nearest dash of the ruler 6.

The measurement accuracy is practically independent of the accuracy of the manufacture of parts of the device (including the telescope 4), since the device's malfunctions are mutually destroyed by a 180 ° rotation. The same applies to the frame of the mirror 7, which has the property of self-checking (as a level, when turning it 180 °).

The necessary conditions for measurement accuracy are: the invariance of the relative position of the instrument parts between the two readings, the quality of the reflecting surface of the mirror 7, the accuracy of the ruler 6 and a sufficient increase in the pipe 4. The inaccuracy of the installation of the axis of the pipe 4 in the measurement plane, due to the smallness of the angles, It can reach 8 ° without noticeable effect on the measurement accuracy. All measurements in one plane (angular and linear) can be combined in time. However, at the same time, it is necessary that the focal device of the tube 4 (the ocular knee or the focusing lens) “e have a backlash, which is structurally easily achievable. To illuminate the scale 5 and ruler 6, the device can be equipped with a flashlight with an electric lamp and a lens.

The subject matter of the invention.

An optical device for checking the position of the engine cylinders and the parallelism of the crank necks and the crankshaft axis, characterized in that the telescope is obliquely mounted on a crossbar overlaid on the upper end face of the cylinder and equipped with a ruler with dividing and adjustable ends on the end stops.

figure 1

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