Dynamic measuring device for worm helix error and pitch error

Abstract

The invention discloses a dynamic measuring device for worm helix errors and pitch errors, which comprises a headstock, a measuring table, a worm to be measured, a machine bed, a tailstock, an interference mirror, a compensator, a laser support, a computer, a laser head, a flat-V-shaped guide rail, a movable pyramid reflecting mirror, a measuring head, a circular grating system, an axial feed transmission assembly and the like. The circular grating system in the headstock and the worm to be measured are driven by the axial feed transmission assembly to realize synchronous rotation. When the worm to be measured rotates, the measuring table is dragged to move on the guide rail through the measuring head. The laser support supports the laser head, the interference mirror and the compensator. The movable pyramid reflecting mirror is fixedly arranged on the measuring table and moves along with the measuring table relative to the laser support. Since the entire instrument is provided with compensation units for temperature, environment and the like, the measuring accuracy is further improved. By using the measuring device, the automatic and dynamic high-accuracy measurement of the helix errors, pitch deviations and accumulated pitch errors of the worm with precision being or above third grade can be realized.

Description

technical field [0001] The invention relates to a device in the field of measurement technology, in particular to a measuring device that uses a circular grating as an angle measuring element, a laser interferometer as a length measuring element, and is controlled by a computer to dynamically measure the pitch error and helix error of a worm. Background technique [0002] Worm drive has the advantages of large transmission ratio, compact structure, strong bearing capacity, stable transmission, low noise, and good self-locking property under certain conditions, so it is widely used in machine tool manufacturing, automobile industry, lifting transportation industry, metallurgical industry And in the fields of precision instruments and equipment, especially in the machine tool manufacturing industry, it has become the main transmission form of general low-speed rotary tables and continuous indexing mechanisms. The precision parameters of the worm mainly include the helix error,...

AI Technical Summary

Problems solved by technology

The shortcomings of this instrument are: 1. The stepping motor is prone to low-frequency vibration at low speed, and because the detection method and device use two stepping motors to drive the worm to rotate and the inductive probe to move axially respectively, it will introduce Synchronization error of the stepping motor; 2. Due to the use of two inductive probes for parameter measurement at the same time, the structure is complex, the installation is difficult, and it is easy to cause mechanical transmission errors; 3. The gas static pressure guide rail must ensure sufficient exhaust channels, otherwise it will cause The position is disturbed, and the amount of disturbance sometimes reaches several microns, but it is difficult to process small holes smaller than φ0.15mm by traditional mechanical processing methods, and it also puts forward high requirements for preventing small holes from being blocked; 4. Environmental factors such as temperature are not considered for measurement Due to the influence of precision, no error analysis and compensation technical measures have been taken. For example, changes in temperature will cause axial expansion of the grating scale, resulting in changes in the grating pitch, and the long grating itself has original line errors, subdivision errors, etc.

All of the above shortcomings will affect the detection accuracy of precision worms, and it is difficult to achieve high-precision measurement of precision worms above grade three

Images