Why is it easier and more accurate to measure with tools?

Because they have scales, it improves people's productivity.

Summary. Name six commonly used measuring tools: rulers, angle rulers, and calipers.

Name six commonly used measuring tools: rulers, angle rulers, and calipers.

Tape measure, level, infrared.

Benchmark. What are the measuring tools that can measure straightness?

Vernier calipers, micrometers, knife-edge rulers, feeler gauges, etc.

Ruler infrared.

1. The ruler method uses the measuring surface of the quartz flat ruler as the known plane to compare with the measured straight line, and records the contour shape of the measured section through the electrical length sensor, the corresponding electronic part and the recorder, or prints out the straightness error. 2. Use the optical collimation telescope system to measure the straightness error. The collimated telescope nuclear system consists of a collimating fluorescent tube and a telescope.

The light emitted by the light source passes through the cross reticle 1 and the objective lens 1, is emitted as parallel light, and then converges on the cross reticle 2 located in the focal plane of the rearranged shed after passing through the objective lens 2 in the telescope, and is read through the eyepiece. 3. Measure with an autocollimator. The measured total length is divided into several segments, and the inclination angle of each segment is measured.

Find straightness by drawing or calculating. 4. Measure the straightness by using the gravity phenomenon of the liquid automatically keeping the level or the weight self-selling to keep the lead straight. A commonly used gauge is a spirit level.

5. Use steel wire and laser beam to measure straightness. When measuring the straightness error of the guide rail of the lathe using a steel wire, the value of each point of the guide rail deviating from the steel wire can be read from the reading microscope mounted on the slide plate by moving the slide. 6. It is used to measure the straightness of the cylinder voxel line or axis.

What measuring tools can be used to measure levelness?

The instruments commonly used in leveling measurement mainly include level, Jingweiyi, total station, and steel ruler.

Evaluate the measurement accuracy of the measuring tool under the specified conditions. Common evaluation methods include verification method, comparison method and error separation method.

1. Verification method.

The measuring tool can only be used after passing the verification according to the verification regulations. Generally, the length standard is used for verification, such as: micrometer and caliper are verified with measuring blocks; Use a standard line ruler to verify the length ratio instrument and length measuring machine, etc.

2. Comparison method.

Two or more measuring tools of the same accuracy class are compared with each other to determine their accuracy. This method is suitable for evaluating some measurement tools with high accuracy levels, such as laser interferometers, laser interferometer length meters, etc., because for such high-precision measurement tools, there is no length standard with suitable accuracy for verification.

3. Error separation method.

It is suitable for some high-precision (small shape error) and measurement tools with closed circumferential angles. For example, to verify the grade 1 flat crystal, if the flatness error of the three flat crystals to be inspected is x, y, z respectively, then they are combined according to 1 and 2, 2 and 3, 3 and 1 to check the flatness of each other. The resulting magnitude values are a, b, and c.

List the equations x+y=a, y+z=b, x+z=c. After solving the equation, the magnitude of x, y, and z can be found. In addition, this method can also be used for roundness meters and multi-tooth indexing tables.

This method can also be used with commonly used quartz glass spherical roundness meters and multi-tooth indexing tables. Quartz glass balls are commonly used to verify the roundness meter, because the glass balls also have errors, so the multiple indexing method is used to separate the respective errors of the glass balls and the precision shafting of the roundness meter. The multi-tooth indexing table also takes advantage of its closed circumference to overlap two multi-tooth indexing tables together, rotate them in the opposite direction to the same angle in turn, read out their magnitudes from the monochromatic light autocollimator, and process a series of measured magnitudes to obtain the respective indexing error of each unit.

Measuring tools can also be divided into mechanical, optical, pneumatic, electric and optoelectronic types according to their working principle. This classification method is shaped by the history of the development of measuring tools. However, some modern measuring tools have developed into measurement tools that use the principles of precision mechanics, optics, electricity, etc., and combine them with electronic computer technology, so this classification method is only suitable for measuring tools with a single working principle.

Spiral micrometer, also known as micrometer, spiral micrometer, centimeter card, is a more precise tool than vernier caliper to measure the length, with which the length can be accurately measured, the measurement range is a few centimeters.

The following is a schematic diagram of the structure of the spiral micrometer:

How the spiral micrometer works:

The spiral micrometer is made according to the principle of spiral amplification, that is, the screw rotates once in the nut, and the screw moves forward or backward by one pitch along the axis of rotation. Thus, the slightest distance traveled in the direction of the axis can be expressed by a reading on the circumference.

How to use the spiral micrometer:

1) The zero point should be checked before use

Slowly turn the fine-tuning knob D, so that the measuring rod (F) and the measuring anvil (A) are in contact, until the ratchet makes a sound, at this time, the zero engraved line on the movable ruler (movable sleeve) should be aligned with the reference line (long horizontal line) on the fixed sleeve, otherwise there is zero error.

2) Hold the ruler frame (C) in the left hand, turn the coarse adjustment knob D with the right hand so that the distance between the measuring rod F and the measuring anvil A is slightly greater than the measured object, put in the measured object, turn the protection knob D to clamp the measured object, until the ratchet makes a sound, and turn the fixing knob G to make the measuring rod fixed and read.

Reading method: 1. Read the fixed scale first.

2. Read the half-scale again, if the half-scale mark has been exposed, it will be recorded; If the half-tick mark is not exposed, it is recorded as ;

3. Re-read the movable scale (pay attention to the estimation). denoted as n;

4. The final reading result is a fixed scale + half scale + movable scale.

Because the reading results of the spiral micrometer are accurate to the millith in mm, the spiral micrometer is also called a micrometer.

Precautions for spiral micrometers.

When measuring, it should be noted that when the micrometer screw is close to the measured object, the knob should be stopped and the fine adjustment knob should be used instead to avoid excessive pressure, which can not only make the measurement results accurate, but also protect the spiral micrometer.

When reading, pay attention to whether the notch on the fixed scale indicating half a millimeter has been exposed.

When reading, there is an estimated digit in the thousandth place, which should not be thrown away, even if the zero point of the fixed scale is exactly aligned with a certain tick line of the movable scale, the thousandth should be read as "0".

When the anvil and the micrometer screw are close together, the zero point of the movable scale does not coincide with the zero point of the fixed scale, and there will be zero error, which should be corrected, that is, the value of zero error will be removed from the reading of the last measured length. Reference.

A measuring tool is a tool for measuring a certain property. Features of the action with measuring tools:

1. It can provide measurement data scientifically and accurately, so as to provide better work and life for relevant workers;

2. The measurement tool can calculate the demand data efficiently, thereby reducing the waste of time and cost.

3. The properties that can be measured by measurement tools include: length, temperature, time, mass, force, current, voltage, resistance, sound, radio, refractive index and average dispersion.

Otherwise, you can't calculate and match.

Coin diameter: Average with vernier calipers over multiple measurements.

Circumference: Measured multiple times, averaged.

Thickness of the paper: Use the same stack of paper, measure the thickness, divide by the total number of pages to determine the diameter of the wire: the method is the same as the previous one.

Circumference; 1 Wrap the coin around the coin with a thread and measure the length of the thread.

2 Place the coin between the right sides of the two triangle rulers and the other right angle on the scale, measure its diameter, and multiply it.

3 Make a mark on the outer circumference of the coin, roll it around the paper, and measure the length of the circumference.

Adopt more sophisticated instruments and more scientific operation methods.