RU2480707C1 - Method to measure angle and device for its realisation - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: position of a primary shaft, rotary motion of which is interconnected with rotation of a secondary shaft, is registered using the first sensor. Using the second sensor, the appropriate angular position of the secondary shaft is registered. The turn angle of the primary shaft is calculated. The device for angle measurement comprises the primary shaft connected with the first geared wheel and the first sensor, the secondary shaft, connected with the second geared wheel and the second sensor. Outputs of the first and second sensors are connected to a computing device.

EFFECT: increased accuracy of operation, simplified design.

2 cl, 1 dwg

Description

The invention relates to the field of measurement technology and can be used: in coordinate systems for tool positioning of numerically controlled machines (CNC), in absolute position sensors of moving or rotating objects.

A known method of mechanical reduction of the number of revolutions of the shaft in the converters of angular quantities [1]. The essence of this method is that with the help of a gear or friction connection of two or more shafts, the number of revolutions and the phase phase of the driven shafts with respect to the lead are changed (mechanical reduction). This allows you to create converters with coarse and accurate sampling systems, which increases the accuracy of the conversion. However, their accuracy is not great, since there are many moving and rubbing parts, many stages of reduction, the degree of reduction (gear ratio) to the transformation range is large, and the mass and dimensions are large.

Closest to the proposed method is a method of correcting the angular error of the sensor of the angular position [2], which allows you to almost completely compensate for the angular error of the sensor of the absolute angular position due to the fact that the sensor of the angular position is a sensor of the absolute angular position, with at least at least one full revolution of the first shaft, the corresponding angular position of the second shaft is recorded, and based on the measured values obtained, it is determined accordingly the angular position of the first shaft, then the corresponding output value of the sensor of absolute angular position is compared with the respective angular position of the first shaft, while maintaining the value obtained as a result of this comparison mismatch, and then each of the respective output calculated absolute angular position of the sensor values is corrected by the corresponding stored value.

The disadvantage of the prototype method is the iterative process of compensating for errors in the mutual angular position of the shafts, the conversion range is limited to one revolution of the input shaft.

Closest to the proposed device is a device for measuring the angle, containing the primary and secondary shafts, the first gear connected to the primary shaft, the first and second sensors [3].

The disadvantage of the prototype device is that the conversion range is limited to one revolution of the input shaft.

The objective of the invention is to improve the accuracy of work, simplifying the design.

далее производят вычисление значения угла поворота первичного вала по формулеThe problem is achieved in that in the method of measuring the angle, including the registration operation using the first sensor of the position of the primary shaft, the rotational movement of which is interconnected with the rotation of the secondary shaft, the registration operation using the second sensor of the corresponding angular position of the secondary shaft, perform calculations in the computing device, according to invention is selected in the number of teeth of the first gear coupled to the input shaft, z _1, the number of teeth of the second gear is connected Nogo with the secondary shaft, z _2, and the number of second gear teeth z ₂ = z ₁ + _1, produce the transformation angle of rotation of primary shaft within a full turn to give the lag angle on the secondary shaft

then calculate the value of the angle of rotation of the input shaft according to the formula

где

Where

φ∑ is the total angle of rotation of the input shaft,

φ ₁ - reference angle of the first angle sensor,

φ ₂ - reference angle of the second angle sensor.

The task is also achieved by the fact that in the angle measuring device containing a primary shaft connected to the first gear with the number of teeth z ₁ and the first sensor, the secondary shaft with the second sensor, according to the invention, a second gear with the number of teeth z ₂ connected further with the secondary shaft, the computing device to which are connected outputs of the first and second sensors and the number of teeth of the second wheel z ₂ = z ₁ + _1, the resolution is determined by the angle resolution of the first transducer a, a measured range of angles determined by the relationship

where m is the number of full revolutions of the input shaft over the entire conversion range.

Achievable technical result of the proposed solution is the ability to calculate the total angle of rotation of the input shaft from the values of the measured values of the rotation angles of the two sensors connected by a gear transmission with a small gear ratio, which simplifies the design of the device and increases its reliability.

The figure shows a diagram of the proposed device for implementing the method of measuring the angle. The device for measuring the angle contains a primary shaft 1 connected to the first gear 2 and the first sensor converting the angle to digital code 5. The gear 4 is connected by the secondary shaft 3 to the second sensor converting the angle to digital code 6. The outputs of the angle converting sensors to the code are connected to the inputs of the computing device 7.

A device for implementing the method includes a primary shaft 1 connected to the first gear 2 with the number of teeth z ₁ and the first angle sensor 5, a secondary shaft 3 connected to the second gear 4 with the number of teeth z ₂ and the second angle sensor 6, and the outputs of the sensors angle connected to the computing device 7, recalculating the readings of the sensors in the value of the absolute angle.

где z₂=z₁+1, достигается упрощение конструкции редуктора и уменьшение погрешности преобразования. При этом разрешающая способность по углу определяется разрешающей способностью первого датчика угла, а диапазон измеряемых углов определяется соотношением

где m - число полных оборотов первичного вала на весь диапазон преобразования.Due to the fact that a small deceleration of the gearbox is used, which is determined by the value

where z ₂ = z ₁ +1, simplification of the design of the gearbox and reduction of the conversion error are achieved. In this case, the angle resolution is determined by the resolution of the first angle sensor, and the range of measured angles is determined by the ratio

where m is the number of full revolutions of the input shaft over the entire conversion range.

За m оборотов первичного вала отставание вторичного вала составит 360°, оставаясь однозначно связанным с углом поворота первичного вала. Тогда вычисленное значение угла поворота первичного вала будет определяться соотношениемThe measurement of the absolute value of the angle of rotation of the input shaft is as follows. The first angle sensor 5 converts the angle of rotation of the input shaft 1 within a full revolution. In this case, the secondary shaft 3 rotates with a lag angle

For m revolutions of the primary shaft, the lag of the secondary shaft will be 360 °, remaining uniquely associated with the angle of rotation of the primary shaft. Then the calculated value of the angle of rotation of the input shaft will be determined by the ratio

где

Where

φ∑ is the total angle of rotation of the input shaft 1;

φ ₁ - reference angle of the first angle sensor 5;

φ ₂ - reference angle of the second angle sensor 6.

Information sources

1. Reference designer REA, edited by Varlamov R.G. "Radio and Communications", Moscow: 1985.

2. RF patent No. 2246020, F02D 41/00, publ. 02/10/2005

3. Patent JP 5203442, F02P 15/00, publ. 08/10/1993

Claims (2)

1. The method of measuring the angle, including the registration operation using the first sensor of the position of the input shaft, the rotational movement of which is interconnected with the rotation of the secondary shaft, the registration operation using the second sensor of the corresponding angular position of the secondary shaft, the calculation in the computing device, characterized in that the number is selected teeth of the first toothed wheel connected to the input shaft, z _1, the number of teeth of the second gear wheel connected with the secondary shaft, z _2, where Nu a second wheel teeth z ₂ = z ₁ + _1, produce the transformation angle of rotation of primary shaft within a full turn to give the lag angle on the secondary shaft

calculate the value of the angle of rotation of the input shaft according to the formula

where φ∑ is the total angle of rotation of the input shaft,
φ ₁ - reference angle of the first sensor,
φ ₂ - reference angle of the second sensor. 2. An angle measuring device comprising a input shaft connected to a first gear with a number of teeth z ₁ and a first sensor, a secondary shaft with a second sensor, characterized in that a second gear with a number of teeth z _{2 is} further connected to the secondary shaft, a computing device to which are connected outputs of the first and second sensors and the number of teeth of the second wheel z ₂ = z ₁ + _1, the resolution is determined by the angle resolution of the first sensor, and the measurement range of angles defined with elations

where m is the number of full revolutions of the input shaft over the entire conversion range.