What Is a Digital Measuring Tape?

Tape measure is a measuring tool commonly used in daily life. Everyone often sees a steel tape measure, which is commonly used in construction and decoration, and is also one of the essential tools for families. Divided into fiber tape measure, tape measure, waist measure and so on. Luban ruler, feng shui ruler, and metric ruler also belong to steel tape measure.

The tape measure head is loose so that we can measure the size. There are two ways to measure the tape measure. One is hanging on the object, and the other is hanging on the object. The difference between the two measurement methods is the thickness of the iron piece on the head of the tape measure. The purpose of loosening the tape measure head is to compensate the iron piece of the tape measure head when it is resting on the object.

The "inner core" of the tape measure has a small piece of steel inside it, which acts like a spring. You can also think of it this way, the one on the trigger of the toy pistol is used to "hit" the small wire of the bullet. When it is pulled out, it is bent and forced, and the external force (referring to the pull force, and the friction force is more Small, less than the elastic force of the small wire) disappeared, so it will spring back automatically. And the front part of the tape measure has a folded part, which works at this time, so that the tape measure is stuck outside so that it will not be fully indented. At the beginning, he was loose. After pulling it out, he tightened. After releasing it, it should have a recovery process, so it will spring back automatically. It was loose in the beginning, it was tight when pulled, there was a spring force between them, and it would spring back naturally.

The main type of tape measure is a steel tape measure, followed by a fiber tape measure, which is a tape measure that everyone often sees. Many people say it is a tape measure, and there is

A tape measure spring is a component similar to a steel tape measure, and is a single-layer open cylindrical shell. A hinge structure can be designed and developed by utilizing the buckling performance of the shell. This hinge structure has unique mechanical properties. It can use the elastic strain energy accumulated during folding to realize the automatic deployment of the structure without the need for other power devices. After deployment, it can provide the large expandable structure required by its own stiffness. Locking force without additional locking device. This kind of hinge can be used in large space expandable structures, such as expandable solar wings. ^[1]

Composition of tape measure parts

The steel tape measure consists of eight parts: housing, ruler, brake, ruler hook, lifting strap, ruler spring, anti-fall protection cover and labeling. The details are as follows

1. Outer shell: ABS new plastic, shiny appearance; anti-fall, wear-resistant, not easy to deform.

2. Ruler bar: 50 # first-grade strip steel with a thickness of 10 wires (0.10mm); the ruler surface is the most advanced environmental protection paint: odorless, smooth and wear-resistant, bright colors, clear and bright scales

3. Braking: With three-dimensional braking on the top, side and bottom, the hand control feels stronger.

4. Ruler hook: Rivet ruler hook structure is not easy to deform and ensure more accurate measurement.

5. Lifting belt: rubber, nylon; high-grade and high-quality; strong and durable, good feel.

6. Ruler spring: generally use 50 # carbon steel, 65 # manganese material: strong toughness, high accuracy.

7, anti-fall protection sleeve: high-quality plastic, to prevent damage and collision damage, enhance durability.

8. Labeling: Labeling can be produced according to customer requirements.

Tape temperature effect

The main structure of a steel tape measure is a whole steel strip with a certain elasticity, and the steel strip has the characteristics of thermal expansion and contraction.

(1) When the temperature of the standard steel tape and the tested steel tape are both 20%, the dimensional error caused by the temperature is zero.

(2) When the standard steel tape and the tested steel tape are of the same material and the same temperature, the dimensional error caused by temperature is directly proportional to the coefficient of thermal expansion and temperature.

(3) When the standard steel tape and the tested steel tape are made of the same material and have different temperatures, the dimensional error caused by temperature is directly proportional to the coefficient of thermal expansion and the temperature difference between the two feet.

(4) When the standard steel tape and the tested steel tape are of different materials and have the same temperature, the dimensional error caused by temperature is proportional to the difference in thermal expansion coefficient of two feet and the temperature of two feet.

(5) When the standard steel tape and the tested steel tape are made of different materials and have different temperatures, the dimensional error caused by temperature is proportional to the difference in thermal expansion coefficient of two feet and the difference in temperature of two feet. ^[2]

Tape measure accuracy

The accuracy of the steel tape measure will directly affect the measurement accuracy, so the steel tape measure must be quality checked during use. At present, most metrology institutes still use manual operations to complete the detection of steel tapes. On the steel tape long inspection table, the errors of the measured steel tapes and standard steel tapes are compared with a microscope. Big. Therefore, the verification mechanism urgently needs a steel tape error automatic detection system that can meet the inspection accuracy of the steel tape measure and improve the inspection efficiency. Aiming at the testing requirements of steel tape measure, an automatic shuttle steel tape measuring system based on CCD image was developed, and image processing software was developed using VisualBaSic6, which could realize automatic image acquisition and processing. The test result report is output, the repeat accuracy is less than 12 points, the operation is simple, and the steel tape measure larger than 10m can be tested in sections. ^[3]