ChineseGrating ruler, also known as grating ruler displacement sensor, is a measurement feedback device that works on the optical principle of grating. Grating ruler is often used in the closed-loop servo system of CNC machine tools, and can be used to detect linear displacement or angular displacement. Its measurement output signal is a digital pulse, which has the characteristics of large detection range, high detection accuracy and fast response speed. For example, it is often used in CNC machine tools to detect the coordinates of tools and workpieces to observe and track tool feeding errors, so as to play a role in compensating tool motion errors.
Grating ruler definition: Grating ruler is a high-precision displacement sensor that digitally represents linear displacement through the principle of moiré fringes and photoelectric conversion. Grating line displacement sensors are mainly used in linear moving guide mechanisms, which can realize accurate display and automatic control of movement. They are widely used in digital display of metal cutting machine processing volume and control of CNC machining center position ring. This product has formed a series for selection of various machine tools of different specifications, with a range from 50 mm to 30 meters, covering almost all metal cutting machine tool travel.
The grating ruler is classified as follows: 5V, 12V, 15V, 24V square wave, subdivision ruler, sine ruler, there are also positive and negative code signal rulers with strong anti-interference ability specially provided for spark machines, and high-power grating rulers connected to computer numerical control machine tools. The structure is divided into wide ruler and narrow ruler. The narrow ruler can be made up to 1 meter, and the wide ruler can be selected within 30 meters. In addition, it can be divided into open type and closed type. Among them, the open type is a high-precision type, and the output waveform is a sine wave. It is mainly used for the digital transformation of precision instruments with a maximum resolution of 0.1um. The closed type is mainly used for the digital transformation of ordinary machine tools and instruments, and the output waveform is a square wave. Structure The grating ruler consists of two parts: the scale grating and the grating reading head. The scale grating is generally fixed on the movable part of the machine tool, the grating reading head is installed on the fixed part of the machine tool, and the indicator grating is installed in the grating reading head. The right picture shows the structure of the grating ruler. [1] Grating detection device structure The key part of the grating detection device is the grating reading head, which is composed of a light source, a converging lens, an indicating grating, a photoelectric element and an adjustment mechanism. There are many structural forms of grating reading heads. According to the structural characteristics of the reading head and the application occasion, it is divided into a direct receiving reading head (also called a silicon photocell reading head, a mirror reading head, a spectroscope reading head, and a metal grating reflection reading head). GBC-Q series grating scale Grating scale definition: The grating scale uses the principle of moiré fringes and photoelectric conversion to digitally represent the linear displacement of a high-precision displacement sensor. Grating line displacement sensors are mainly used in linear motion guide mechanisms, which can realize accurate display and automatic control of the movement amount. They are widely used in the digital display of the processing amount of metal cutting machine tools and the control of the position ring of CNC machining centers. This product has formed a series for selection by various machine tools of different specifications, with a range from 50 mm to 30 meters, covering almost all the travels of metal cutting machine tools. The grating rulers are classified as follows: 5V, 12V, 15V, 24V square wave, subdivision ruler, sine ruler, there are also positive and negative code signal rulers with strong anti-interference ability specially provided for spark machines, and high-power grating rulers connected to computer numerical control machine tools. The structure is divided into wide ruler and narrow ruler. The narrow ruler can be made up to 1 meter, and the wide ruler can be selected within 30 meters. In addition, it can be divided into open type and closed type. Among them, the open type is high-precision type, the output waveform is a sine wave, and it is mainly used for the digital transformation of precision instruments with a maximum resolution of 0.1um. The closed type is mainly used for the digital transformation of ordinary machine tools and instruments, and the output waveform is a square wave.
Main applications of grating rulers:
1. Displacement measurement of various measuring mechanisms and instruments: spring testing machine, three-coordinate machine, projector
2. Digital display system of various machine tools: lathe, milling machine, grinder, boring machine, electric spark, drilling machine, etc.
3. Supporting use of various CNC machine tools: CNC milling, machining center, CNC grinding, etc.
4. Connected with PLC, used for displacement measurement of various automation mechanisms.
Product features:
1. The most advanced optical measurement system adopts a reliable and durable high-precision five-bearing system design to ensure the stability of the optical mechanical system, excellent repeatability and high-level measurement accuracy.
2. The sensor adopts a sealed structure with reliable performance and easy installation.
3. It adopts special oil-resistant, corrosion-resistant, highly elastic and anti-aging plastics for waterproofing, excellent dustproof and long service life.
4. Specific high level of anti-interference ability, stable and reliable.
5. The light source adopts imported infrared light-emitting diodes, which are small in size and long in life.
6. Using advanced grating production technology, high-precision grating glass rulers of various specifications can be produced
Installation Guide
The installation of grating ruler linear displacement sensor is relatively flexible and can be installed in different parts of the machine tool.
Generally, the main ruler is installed on the workbench (slide plate) of the machine tool, and moves with the machine tool. The reading head is fixed on the bed, and the reading head is installed below the main ruler as much as possible. The choice of its installation method must pay attention to the splashing direction of chips, cutting fluid and oil. If the reading head must be installed upward due to installation position restrictions, an auxiliary sealing device must be added. In addition, under normal circumstances, the reading head should be installed on the stationary part relative to the machine tool as much as possible. At this time, the output wire does not move and is easy to fix, while the ruler body should be installed on the part that moves relative to the machine tool (such as the slide plate).
1. Installation base of grating ruler linear displacement sensor
When installing the grating ruler sensor, the sensor cannot be directly installed on the rough and uneven machine tool body, let alone on the primer painted machine tool body. The grating main ruler and the reading head are installed on the two parts of the machine tool that move relative to each other. Use a micrometer to check the parallelism between the main scale mounting surface of the machine tool worktable and the direction of guide rail movement. The micrometer is fixed on the bed, and the worktable is moved to achieve a parallelism of within 0.1mm/1000mm. If this requirement cannot be met, a grating scale base needs to be designed and processed.
The base requirements are as follows:
(1) A base with the same length as the grating scale body should be added (it is best that the base is about 50mm longer than the grating scale).
(2) The base is processed by milling and grinding to ensure that its plane parallelism is within 0.1mm/1000mm.
In addition, a reading head base with the same height as the scale body base needs to be processed. The total error between the reading head base and the scale body base shall not exceed ±0.2mm. During installation, adjust the reading head position to achieve a parallelism of about 0.1mm between the reading head and the grating scale body, and a spacing of about 1~1.5mm between the reading head and the grating scale body.
2. Installation of the main scale of the grating scale linear displacement sensor
Use M4 screws to fix the grating main scale on the installation surface of the workbench installed on the machine tool, but do not tighten it. Fix the micrometer on the bed and move the workbench (the main scale and the workbench move at the same time). Use the micrometer to measure the parallelism between the main scale plane and the movement direction of the machine tool guide rail, adjust the position of the main scale M4 screw, and when the main scale parallelism meets the requirement of within 0.1mm/1000mm, tighten the M2 screw thoroughly.
When installing the grating main scale, pay attention to the following three points:
(1) When installing the main scale, if the grating is larger than 1.5M, it is not possible to install only the two ends like the bridge type, but it is necessary to have support in the entire main scale body.
(2) After installation with a base, it is best to clamp the midpoint (or several points) of the scale body with a clip.
(3) When the clip cannot be installed, it is best to use glass glue to stick the grating scale body to fix the base scale and the main scale.
3. Installation of the reading head of the grating scale linear displacement sensor
When installing the reading head, first ensure that the base surface of the reading head meets the installation requirements, and then install the reading head. The installation method is similar to the main scale. Finally, adjust the reading head to ensure that the parallelism between the reading head and the grating main scale is within 0.1mm, and the gap between the reading head and the main scale is controlled within 1~1.5mm.
4. Limiting device of grating scale linear displacement sensor
After all the grating linear displacement sensors are installed, the limiting device must be installed on the machine tool guide rail to prevent the reading head from colliding with the two ends of the main scale when the machine tool processing product moves, thereby damaging the grating scale. In addition, when purchasing grating linear displacement sensors, users should try to choose grating scales that exceed the machine tool processing size by about 100mm to leave a margin.
5. Inspection of grating linear displacement sensor After the grating linear displacement sensor is installed, the digital display can be connected, the workbench can be moved, and the digital display count can be observed to see if it is normal. Select a reference position on the machine tool and move the working point back and forth to the selected position. The readings of the digital display should be the same (or return to zero). Alternatively, a micrometer (or percentage indicator) can be used to adjust the micrometer and the digital display to zero (or memorize the starting data) at the same time. After going back and forth several times, return to the initial position and observe whether the data of the digital display and the micrometer are consistent.
Through the above work, the installation of the grating scale linear displacement sensor is completed. However, for general machine tool processing environments, there are more iron filings, cutting fluids and oil stains. Therefore, the sensor should be equipped with a protective cover. The design of the protective cover is determined by enlarging the cross-section of the sensor and leaving a certain space size. The protective cover is usually sealed with rubber to make it waterproof and oil-proof. [5] Features of milling machine digital display: automatic centering function, metric/imperial display. Absolute/relative counting conversion function; scale storage function; linear error compensation; oblique line hole division function; circumferential hole division function; circumferential arc processing function. Inclined surface processing function. Calculator function, nonlinear error compensation.
I. Technical parameters of digital display
1. Voltage range: AC 80V～260V/50Hz～60Hz
2. Power consumption: 25VA
3. Number of coordinates: two coordinates, three coordinates
4. Display: 7-bit display with sign (two or three axes) data information window uses eight-bit meter character display symbol output
5. Frequency multiplication: 4X
6. Display box allows input signal: TTL square wave
7. Allowable input signal frequency: >100KHz
8. Length resolution 10μm, 5μm, 2μm, 1μm, 0.5μm
9. Operation keyboard: touch keyboard
10. Grating ruler: grating pitch is 0.02mm, 0.01mm, power supply is +5V, outputs two TTL square wave signals with a phase difference of 90°
II. General/processing functions of digital display:
1: clear;
2: preset number;
3: metric/imperial conversion;
4: absolute/relative coordinate conversion;
5: 200 groups of user coordinate display;
6: power failure memory;
7: 1/2 value function key display;
8: line Error correction;
9: Sleep shutdown;
10: 200-point auxiliary zero position function;
11: Automatic zero position search function;
12: Calculator function;
13: Circular hole division;
14: Oblique line hole division;
15: Oblique processing;
16: Arc processing;
17: Lathe function (optional);
18: Rectangular cavity progressive processing;
19: Digital filtering;
20: Radius/diameter display (optional);
21: RS- 232-C interface (optional);
22: EDM output, etc.
Can
meet the needs of most machine tool processing.
1: Fast counting frequency response speed and powerful functions;
2: Die-cast alloy shell, surface electrospraying treatment, dustproof and wear-resistant, good shielding;
3: Professionally designed independent power supply, wide adaptability, high stability, strong anti-interference ability;
4: High-quality and durable key panel, simple and convenient replacement
5: Directly perform function calculations on the digital display, convenient processing, etc.
III. Installation conditions
1. The digital display can work in an environment of 0℃～+40℃. It must not be exposed to the sun or high temperature.
2. Stay away from high voltage, high current, and strong magnetic field equipment, and the grating ruler signal cable should be kept away from the power cord as much as possible.
3. Avoid metal chips, oil, water, etc. from entering the digital display. Pay attention to dust and moisture; do not install this device on a workbench with large vibration or instability.
4. When the ambient temperature is +40℃, the relative humidity of the air shall not exceed 50%. A higher relative humidity is allowed at a lower temperature. Special measures shall be taken for condensation caused by temperature changes.
III. Installation of combined accessories
Due to the different structures and working environments of various machine tools, there is no unified standard for the installation of sensors. In order to take into account the installation of various machine tools, our company has specially produced various combined accessories for users to choose from, including sensor covers, mounting aluminum strips, digital display mounting frames, angle aluminum, mounting aluminum plates, etc.
The digital display is widely used in various types of machining machines such as lathes, milling machines, grinders, wire cutting, radial drills, electric sparks, boring machines, gantry boring and milling machines, etc., which is conducive to improving machining efficiency and machining accuracy.
I. Application The linear displacement grating sensor digital display system is mainly used for the measurement of linear motion guide mechanisms or precision displacements. It can realize high-precision display and automatic control of the movement amount. It has been widely used in machine tool processing and precision measurement of instruments. At present, this product has formed various series with complete varieties, exquisite workmanship and precise technology. It can be used for digital transformation of various machine tools and instruments of different specifications, and can also be specially produced according to the special needs of users. The corresponding digital display system can be used for lathe modification, milling machine modification, boring machine modification, grinder modification, spark machine modification, drilling machine modification, wire cutting modification, coordinate measurement, projection measurement, etc.
II. Selection
1. According to the appearance, there are: 50mm-3000mm
2. According to the resolution, there are: 1um----5um
3. According to the power supply voltage, there are: 5V----24V
4. According to the output signal, there are TTL square wave, TTL square wave, HTL square wave (5V, 12V, 15V, 24V), RS422 signal, sinusoidal voltage signal 1Vp-p III. Technical parameters Grid pitch: 0.01mm (100 line pairs/mm), 0.02mm (50 line pairs/mm), 0.04mm (25 line pairs/mm) Accuracy: ±0.008mm, ±0.01mm, ±0.015mm, (20℃ 1000mm) Reference mark: 25mm interval, 50mm interval, 100mm interval, 200mm interval, or set an absolute position reference point (ABS) at any position of the full range