A micrometer caliper, also known as a screw gauge, is a precision instrument used for accurately measuring small lengths.
Structure: It mainly consists of a fixed scale, a movable scale, a micrometer screw, a fixed jaw, a movable jaw, and a ratchet. The fixed scale provides a basic reference for measurement, while the movable scale is used to make fine - tuned readings. The micrometer screw is the key component that converts rotational motion into linear motion, and the two jaws are used to hold the object being measured. The ratchet is used to control the movement of the jaws and ensure a consistent measuring force.
Working Principle: It operates based on the principle of screw transmission. When the movable scale is rotated, the micrometer screw moves forward or backward. Typically, the pitch of the screw is 0.5 mm, meaning that for each complete rotation of the movable scale, the screw advances or retracts by 0.5 mm. The movable scale is divided into 50 equal parts, with each small division representing 0.01 mm. With an additional estimated digit, the measurement accuracy can reach 0.001 mm.
Usage Method: To use a micrometer caliper, first place the object to be measured between the fixed jaw and the movable jaw. Then, gently turn the ratchet to bring the jaws closer to the object until they make contact with the object and the ratchet emits a "clicking" sound. At this point, read the integer part on the fixed scale and the decimal part on the movable scale, and add them together to obtain the measurement result.
Application Scenarios: Micrometer calipers are commonly used in fields such as mechanical processing, electronic manufacturing, and precision instrument manufacturing. They can measure the outer diameter, inner diameter, thickness, length, and other dimensions of workpieces, and are an essential precision measurement tool.
