Indicator of the watch type: description, characteristics of the device

The indicator of the hour type is a device intended for relative measurements of shape deviations, external dimensions, and the location of surfaces. It represents a system of connecting gears and levers, which strengthen the movement of the rod and convert these movements into the readings of the device. In most clock-type devices, moving the measuring rod of the device by one millimeter corresponds to one turn of the arrow. In this case, the division price, and consequently the value of the rod displacement, which the device can reliably measure, is 0.01 mm. Limits of measurements are 0-5 mm and 0-10 mm. Indicators of the hour type are of three classes of accuracy: zero, first, and also second. Instruments of zero type allow the smallest measurement error, while the second class has the greatest error.

For the purpose of relative measurements in the field of bench-and-tool production in labor-intensive places and in the manufacture of various parts, a lever-toothed indicator of especially small dimensions is used.

The hour-type indicator is also used to measure the beat of cylindrical parts or to check the parallel sides of the product, for example, prisms. In order to determine the beat value, the part must be installed on the centers of the special device.

All the hourly indicator devices are unified. They produce models of devices splashproof on the basis of three stones, with unloading in case of impact on the rod, with a measuring range of 0-25 mm and 0-50 mm.

The indicator of the clock type is able to measure the depth of the drilled holes. Such instruments, like micrometers, have a measurement accuracy of 0.01 mm. The small arrow of the device points to millimeters, and the large one to the hundredths of a millimeter. To measure the internal diameter, use a special device, which is put on the indicator.

The hour indicator serves to determine the deviation in the dimensions or the position of the part to be checked. Due to the fact that the dial is divided into 100 parts, the reading is made with an accuracy of 0.005 mm. The dial of the instrument has a zero-sided calibration from zero: divisions on the right side denote deviation of dimensions in the direction of increase, respectively, in the left direction - in the decreasing direction.

For the measurement of linear quantities, deviation of the geometric shape, as well as mutual placement of the surfaces of the parts, a time-type indicator with additional devices is used. Such measurements are carried out using the absolute measurement method, when the measured value does not exceed the measurement limit of the instrument scale, and by the relative measurement method, by checking with the end length measure.

There are indicators based on the use of gears. In such devices, the spring-loaded measuring rod and the rack are structurally implemented as a single unit. The rack is meshed with a 16-tine wheel.

In conclusion, we note that hour-type indicators are the most common and widely used in the designs and elements of control devices by measuring devices. These devices with a 0.01 mm dividing price are used extremely rarely - first, from the fact that the control of parts and blanks does not require such high accuracy, and secondly, due to the rapid wear of measuring devices when working in a forging- Stamping and foundry shops.