AMO circular measuring ruler

AMOSIN ○ R - General Information
AMO has been proven to be innovative in length and angle measurement technology, using optical etching to form a high-precision grid measurement system on a steel tape ruler. Based on this, the sensor's built-in computational electronic circuit (ASIC) has been further developed, creating a new and powerful measurement system. AMOSIN's angle measurement system is an open hollow measurement system, therefore it has no bearings and does not require couplings or mechanical connections. A fully inductive AMOSIN system with an accuracy of ± 5 μ m/m. However, AMOSIN has more advantages, such as strong resistance to environmental impacts such as dust, moisture Wait. It has high resistance to impact and mechanical vibration.
High precision mainly comes from the rigorous measuring scale process and outstanding sensor signal quality. In high-precision grid spacing separation accuracy, the deviation accuracy of sin waves is less than 0.1% of the harmonic constant.
From the following measurement principles, it can be seen that the measurement system does not contain any magnetic components (including measuring tape and reading head), so it can resist any
The electromagnetic field interference does not cause hysteresis, forming a strong contrast with magnetic measurement systems.
This system can output 1 Vpp sine/cosine signal or true time RS-422 square wave signal.
The large-scale AMOSIN angle measurement system represents a wide range of application areas that can be used for small and extremely accurate rotations
Operate the machine spindle at high speed and close to the control speed.
Show their value under high power range and rigidity requirements.

General characteristics
Not easily affected by pollution, resistant to dust/IP67
Not easily affected by electromagnetic fields
● High precision and resolution
● High speed
● Central measuring unit
● Built in reference markers can also be made into location codes
Characteristics of the new generation
Analog output signal (1 Vpp), with a signal period of up to 40 μ m. Can be transmitted freely (the basic period of 1000 μ m can be divided into up to 32 equal parts)
● Digital output RS-422/TTL, decimal resolution: 0.25 μm (1000μm/4000)，1μm (1000 μm/1000)
Enhance analog and digital output input frequency (rotation speed) (analog to 46000rpm)
In terms of product types, a grid spacing of 3000 μ m can achieve high installation tolerances and a rotation speed of over 100000rpm
The standard operating temperature range has been expanded to 0~70 ℃.
The dependence of system accuracy on operating temperature is greatly reduced.
● Strengthened the reading head space (gap between reading head and ruler body) and tolerance range
The impact of installation deviations within the specified range on system accuracy is greatly reduced.
Miniature amplification circuit, integrated into the coupler housing.
Typical applications
● Rotating worktable
● Rotation axis
● C-axis
● Spindle
● Direct driver
Medical equipment
Equipment printing
● Rolling axis positioning
● Punching machine
● Electronic manufacturing equipment

AMOSIN - Measurement Principle
The function of AMOSIN measurement system is based on the principle of moving magnetic reluctance coil transformer, where the changes in the primary and secondary winding of the transformer induced by each other are relative to the position of the coil.
The basic components of the AMOSIN system include a planar coil structure and a measuring ruler (Figure 1). The coil structure with many winding components in the lower layer extends horizontally along the measurement direction, mainly consisting of independent primary and secondary SIN/COS coils.

We used micro multilayer technology. The main measuring ruler is made of stainless steel strip with high-precision optical etching to create a variable magnetic resistance pitch scale (e.g...=1000 μ m).
The relative motion of the measurement direction will change the periodic interaction between independent coils between the sensor structure (on the reading head) and the measuring scale (measuring flange), generating two Sin waves with a signal angle difference of 90 ° (SIN and COS).
This signal quality is very accurate and can resist environmental influences. In fact, after the signal is stabilized by the computational electronic circuit (Figure 2), the deviation from the ideal Sine wave is only less than 0.1%. This result allows for high segmentation factors (further segmentation by one stage) to be achieved after signal digitization, whether in the read head or in the interface of the next stage (such as CNC).

An important feature of the operating principle is that the use of AMOSIN does not cause any measurement lag error. mutually
Compared to measurement systems with magnetism, high frequencies can cause hysteresis in materials.
The computational electronic circuit generates continuous sensor signals, and through a new circuit principle, different differential interfaces or linear drivers are used in real-time
Send measurement information with signals of sine wave or square wave.
In addition to the periodic signals (A, B, and their inversions), there is a reference signal to determine the absolute position output, which is separately measured on the ruler
The marking is generated without the need for other parts.

measurement accuracy
As an open modular structure angle measurement system, the components of the system can be individually provided with measuring rulers and reading heads (even amplifiers),
And there is no need for mechanical connection with bearings, the accuracy is allocated to these parts as follows:
1. Accuracy - determined by the accuracy of the measuring scale on the measuring flange and the deviation of the measuring flange from the ideal roundness.
2. The accuracy of the spacing between each grid - mainly determined by the read head, depends on the quality of the sensor signal and its amplifier.
When the measurement system has a 1Vpp output interface, the following properties should also be considered:
3. Analog/digital conversion at the subsequent electronic signal input (in the controller)
When the signal is converted from the reading head to the subsequent electronic circuit, interference will combine to enter the output signal.
Detailed description after the viewpoint:
1. Scale accuracy
Each measuring flange has been calibrated on an angle testing platform, along with a test certificate, and the precision level is defined based on specifications
The absolute angle deviation of an open measurement system depends on the concentricity of the flange with respect to the measurement axis, as shown in the measurement curve diagram (in an ideal safe environment)
Measurement under installation conditions, as shown in the figure below, is provided as an optional item.

For applications that require the highest precision, the measured flange should be centered as much as possible. The error of angle measurement depends on the error of the scale
The concentricity of the difference and assembly. The error caused by this can be compensated by the controller.
In the special available system architecture, two reading heads can be placed at 180 ° positions to eliminate the problem of angle data averaging
Unusual errors in the circuit box
2. Accuracy of spacing between each grid
The ideal SIN wave signal error was displayed in the initial measurement data. The grid waveform signal is stable, as mentioned in the introduction:
AMOSIN System can achieve an accuracy of 1 μ m arc length! (1/1000 of the spacing of 1000 μ m). The construction of this high-precision level is not
Just for the sake of ideals, for environmental protection, and more importantly, to meet functional certification in terms of all geometric installation deviation accuracy or temperature control
standard.
In order to overcome the errors in items 3 and 4 discussed earlier, a new output interface has been implemented in the new generation AMOSIN system
In the 1Vpp output interface, the sine, cosine, and reference signals are divided above the linear driver.
Synchronized raw signal decoding (e.g. 1000 μ m) reduces the Sin waveform to less than 40 μ m During the arc length, at the programmable read head 'D'
It can be interpreted.
In subsequent electronic signals (such as controllers), any deviation that may cause calculation (A/D conversion) is addressed by dividing factor (D)
Provide and reduce in this signal interface. In addition, the reduced pitch of the sine signal will result in better quantization of the subsequent electronic signal,
This is quite important for the application of transmission equipment that requires high dynamics and robustness.
In addition, dividing the signal to reduce interference is combined with the signal transmission line, proportional to the division coefficient "D"; In other words, obtaining an improved message
Number/noise ratio.
The measurement principle of AMOSIN system operation indicates that they have no hysteresis phenomenon and will not cause any reaction results.

Measurement system structure

Manufacture closed measurement rings using special techniques. This is to tightly weld two components of the same shape that are interrelated in the measurement
On the flange surface, or directly as a thin WMR type measuring ring; Assemble according to customer requirements.

Transform the new measuring scale WMR into a thin, enclosed ring for measuring angles or rotational speeds, providing high flexibility in driving device design

The installation method is to install the measuring ring onto the measuring flange surface of the existing rotating structure of the machinery.

Advantages of other measurement ring designs:
Extremely low inertia
The spindle unit for installing the measuring ring can be made of any material
Due to the highly stable structure of the measurement ring, the design of the high-speed sensor unit (Fig.3) is unique to the AMOSIN angle measurement system.

A planar coil array consists of many coil units and is suitable for flexible substrates. Therefore, its radius can be suitable for the specified (measuring flange) diameter. This configuration is very suitable for signals with an average spacing exceeding several grids. A flat scanning surface, such as glass or hard surfaces
Silicon substrates contain unique and easily influenced elements, and their effects can only approach this, making them less stable for scanning cylindrical scales.

These angle measurement systems can be used in harsh environmental conditions that require accuracy, such as oil, dust, coolant, etc., with a protection level of IP67

The specially designed measurement system allows customers to easily integrate it into existing machines, regardless of whether the machine parts with integrated measurement rings are supplied by us or manufactured by AMO. This special mechanical part, including the measuring ruler, can be customized according to the customer's drawings.

In the design of the basic components of the measurement system:

The application of measuring scales, sensors, and amplifiers is very flexible and can adapt to any specific application requirements. Further main choices
Standard:

1. Grid spacing - l=1000 μ m can achieve high accuracy
-L=3000 μ m may have a large installation tolerance
2. Scanning method: The reading head is relative to the scanning body
-External scanning
-Internal scanning
3. Measuring scale: - Measuring flange
-Measurement ring
4. Reading head: - amplifier placed in a small reading head of the connector
-Fully built-in amplifier

Generally speaking, any form of measuring scale can
Combined with any reader version, the following characteristics are
The conditions for matching the two:
● Grid spacing
● Scanning method
The number of grid spacing per circle