A system for measuring fence posts in a fence run includes a leading unit and a trailing unit. The leading unit includes a first measurement wire extending through a first rotary encoder and terminating in a second rotary encoder, a second measurement wire terminating in a third rotary encoder, and a third measurement wire terminating in a fourth rotary encoder, as well as a clamp to secure the leading unit to a fence post. The trailing unit includes a first rotary encoder to engage with the first measurement wire of the leading unit and a measurement wire terminating in a second rotary encoder, as well as a clamp to secure the trailing unit to a fence post.

The height measuring device is movably positioned on a scale surface, the height measuring device comprises: a bracket repeatedly attached to or detached from the scale surface; and a measuring unit assembled with the bracket, wherein the measuring unit includes a folding position and an extending position relative to the bracket, the measuring unit is close to the bracket in the folding position, and the measuring unit is perpendicular to the scale surface in the extending position. Then, it is convenient to accurately measure the height of users at kinds of objects with a scale surface.

A system for measuring fence posts in a fence run includes a leading unit and a trailing unit. The leading unit includes a first measurement wire extending through a first rotary encoder and terminating in a second rotary encoder, a second measurement wire terminating in a third rotary encoder, and a third measurement wire terminating in a fourth rotary encoder, as well as a clamp to secure the leading unit to a fence post. The trailing unit includes a first rotary encoder to engage with the first measurement wire of the leading unit and a measurement wire terminating in a second rotary encoder, as well as a clamp to secure the trailing unit to a fence post.

The disclosure relates to a vertical displacement detecting device, comprising a fixed frame, a first guiding rail and a second guiding rail. The first guiding rail and the second guiding rail are respectively provided with a first sliding block and a second sliding block. The top or bottom surface of the blocking plate is contacted with a displacement detector. The second sliding block is provided with a traction wire. A top end of the fixed frame is provided with a pulley and a traction wire, and the traction wire is wound around the pulley, one end of the traction wire is connected with the first sliding block and the other end is connected to the second sliding block. The disclosure has the advantages of simple structure, accurate precision, low cost and simple realization method, and it is advantageous for wide use.

The disclosure relates to a vertical displacement detecting device, comprising a fixed frame, a first guiding rail and a second guiding rail. The first guiding rail and the second guiding rail are respectively provided with a first sliding block and a second sliding block. The top or bottom surface of the blocking plate is contacted with a displacement detector. The second sliding block is provided with a traction wire. A top end of the fixed frame is provided with a pulley and a traction wire, and the traction wire is wound around the pulley, one end of the traction wire is connected with the first sliding block and the other end is connected to the second sliding block. The disclosure has the advantages of simple structure, accurate precision, low cost and simple realization method, and it is advantageous for wide use.