RU2043602C1 - Photoelectric meter of object dimensions - Google Patents

Abstract

FIELD: measurement technology. SUBSTANCE: photoelectric meter has pulse generator 1, two pulse counters 2, 10, permanent storage 3, two decoders 4,7, matrixes of keys and amplifiers, strips 6,9 of radiators and photoelectric detectors made with unequal periods of positioning of elements simultaneously connected by periods of oscillations of generator in agreement with some rule by one in each strip. Pulse generator, first pulse counter by first input, permanent storage by first out, first decoder, matrix of keys and transmitting strip are connected in series, permanent storage by first output, second decoder, matrix of amplifiers by first input and second pulse counter by first input are also connected in series. In addition permanent storage by second output is coupled to pulse counters by second inputs and strip of detectors is linked to second input of matrix of amplifiers. EFFECT: enhanced accuracy and reliability of measurements. 2 dwg, 1 tbl

Description

 The invention relates to measuring equipment and can be used, in particular, for measuring the diameters of round timber, especially as part of automated systems for accounting and control of technological processes for the production of timber.

 Known photoelectric sensor of the diameters of the logs, including a light source, a collective lens, a screen with a vertical row of slotted holes and a photodetector that performs reciprocating movements in the process along the vertical axis of the screen.

 The disadvantages of the sensor are low measurement accuracy due to the possibility of movement of the measured object along the optical axis of the lens and insufficient reliability due to the use of mechanically moving elements of the devices. A device for measuring the diameters of raw materials containing a radiation source, a raster, a photodetector and a deploying unit made in the form of a closed tape rotating in a plane parallel to the plane of the raster and the reflector located on it. The disadvantages of this device is its complexity, low speed and low reliability due to the use of mechanical sweep of the rays. A device is also known for determining the smallest diameter of round timber, for example logs, containing a slit directional light source, a photoelectric receiver in the form of a series of photoelectric converters, amplification, conversion, switching, memory, and cyclic counter units.

 The device determines the number of unshaded photosensitive elements, which is uniquely associated with the measured diameter of round timber. The disadvantage of this device is the large number of photosensitive elements, and therefore, the complexity and low reliability of the device.

 Closest to the technical nature of the proposed device is a device for measuring the area of opaque flat figures relating to the control and measuring technique. It can be used in measuring machines designed to measure the area of flat figures, for example, patterns, leathers, etc. in leather goods, clothing, fur industries.

 The device uses sources of multipath (scattered) radiation. The measured figure moves in the transverse direction near the line of receivers and is illuminated by the line of emitters. In this case, receivers are used, some of which are on the radiation path of several emitters, emitters, on the emission path of which at least one common receiver is turned on and off alternately, and the signals at the outputs of receivers that are on the radiation path of the same emitter are in the on state are also registered alternately. The disadvantage of this device is the proximity of the line of receivers from the measured object, large errors that occur in the case of displacement of the object along the normal to the line of receivers and emitters, a large number of elements in the line of receivers and emitters.

 In the technical solution, selected as a prototype, a method for measuring the position of an object is proposed. To implement the proposed method, a device is used that contains a pulse generator, two pulse counters, read-only memory, two decoders, matrix keys and amplifiers, a line of emitters and photoelectric receivers.

 The disadvantage of this device is the low accuracy and reliability of the device, the large total number of emitters and receivers, the increased size of the line of receivers or emitters, since the formulas for determining the basic geometric parameters of the rulers do not allow to optimize their values, do not take into account the volumetric nature of the measured bodies.

 The purpose of the invention is to increase the accuracy and reliability of the device while reducing the number of emitters and photodetectors in the rulers, alignment of the openings of the rulers.

This is achieved by the fact that the photoelectric diameter meter of round timber contains a pulse generator, two pulse counters, a read-only memory, two decoders, a matrix of keys and amplifiers, a line of emitters and photoelectric receivers. The latter are made with periods of placement of emitters and photodetectors, determined by the formula
σ = T1 / (2 * r2) = T2 / (2 * r1) = k / 2 where σ is the distance between adjacent beams, and r1 and r2 are the remainders of the decomposition of periods T1 and T2 into factors, k is the largest common divisor of the periods T1 and T2 . The emitters and photodetectors simultaneously turn on one in each line with the oscillation cycle of the generator, and the pulse generator, the first pulse counters on the first input, the read-only memory on the first output, the first decoder, the key matrix and the transmitting line are connected in series, the read-only memory on the first output , the second decoder, the matrix of amplifiers at the first input and the second pulse counter at the first input are also connected in series. In addition, a permanent storage device at the second output is connected to pulse counters at the second inputs, and the receiver line is connected to the second input of the amplifier matrix.

Comparative analysis with the prototype shows that the invention, in contrast to the prototype, always provides equal openings of the locations of the centers of round timber, the line of emitters and the line of receivers (i.e. 2 * N * T2 2 * M * T1 σ * Q, where Q is the number of intervals ( σ) .In this case, the maximum inclination of the rays w is limited by
tg w T0 / (x1 + x2), where T 0 = r1 * T1 r2 * T2 r1 * r2 * k.

 As a result of this, a quasi-parallel field of rays and a small dependence of the measurement error of round timber on the displacement of objects along the x axis can be obtained (see Fig. 2). In the invention, the interval σ is determined by the value of T1 / (2 * r2) or T2 / (2 * r1) or the common factor k. As a result of this, unlike the prototype, for the same σ interval, for the chosen values of x1 and x2, there are many values of the periods T1 and T2, which allows us to optimize these sizes and, therefore, optimize the total number of emitters and photodetectors. Thus, the proposed device meets the criteria of the invention of "novelty."

 Comparison of the invention with other technical solutions shows that the elements used in the invention, including the line of receivers and emitters, are widely known. However, the invention for the placement of emitters and photodetectors in rulers and the use of elements with the proposed relationships and time characteristics in the diameters of round timber is characterized by a new set of essential features. This allows us to conclude that the technical solution meets the criterion of "significant differences".

 In FIG. 1 shows a block diagram of a device; in FIG. 2 the location of the emitters, receivers and the measured object, the rays between the emitting and receiving elements.

 The device comprises a pulse generator 1, a first pulse counter 2, a read-only memory 3, a first decoder 4, a key matrix 5, a transmitting array 6, a second decoder 7, an amplifier matrix 8, a receiver array 9 and a second pulse counter 10.

 The device operates as follows.

 Pulse generator 1 generates a sequence of clock pulses, which is fed to the first pulse counter 2. At the output of this counter, with each pulse 1, addresses of the read-only memory 3 are generated, by which a code is generated at the output 1 of the read-only memory. The first part of this code goes to the decoder 4, and the second to the decoder 7. The decoders generate signals that supply voltage to the emitting elements of the transmitting line using the key matrix in the desired sequence and connect the outputs of the elements of the receiving line to the counter using the amplifier matrix 10. Fragment of the sequence the inclusion of emitting and receiving elements is shown in FIG. 3. From FIG. 2, 3 it follows that both horizontal and inclined beams are used to measure the diameter D with a discrete σ. In this case, the measurement discrete (see Fig. 2) will be a fraction of the periods of placement of the elements of the receiver and transmitter.

The relationship between the periods T1 and T2 of the placement of the elements of the transmitting and receiving lines and the discrete σ is determined by the relation (for the case when x1 | x2 |)
σ T1 / (2 * r2) T2 / (2 * r1), where r1 and r2 are integers of the decomposition of periods T1 and T2 into common factors.

 After a sequential review of points 0, 1, 2, 3, and data output from the counter 10, the read-only memory 3 at the second output generates a signal R, which returns the counters 2 and 10 to their initial state. Next, the measurement process is repeated.

 Pulse generator 1, counters 2 and 10, memory 3, decoders 4 and 7 are made on microcircuits, a matrix of keys on transistors, a block of amplifiers based on operational amplifiers and logic circuits that provide switching amplifiers.

 Experimental studies of the proposed photoelectric meter for the diameter of round timber showed that, compared with a device of a similar purpose (prototype), the proposed device has fewer elements in the lines of the receiver and transmitter, consumes less energy, since only one emitter and one photodetector are turned on at any time, has increased reliability and lower cost.

 σ T1 / (2 * r2) T2 / 2 * r1). The specified formula is obtained from the following relationships.

 2.1. The initial ratio.

 2.1.1. The period of the emitters is T1. The emitters have the coordinates: x x1, y m * T1 (m 0, ± 1, ± 2, ± M).

 2.1.2. The period of the receivers is T2. The elements of the receiver line have the coordinates: x x2, y n * T2 (n 0, ± 1, ± 2, ± N).

 2.1.3. The center of the measured round timber is placed on the line x 0 (vertical line in Fig. 2).

 2.1.4. The units of measurement of the coordinates x1 and x2 and the periods T1 and T2 are selected such that their values are integers.

 2.2. Corollaries from the initial relations.

2.2.1. From 2.1.4 it follows that the numbers x1 and x1-x2 can be factorized, one of which (k1) is the largest common divisor of x1 and x1-x2, and c and d are integers, respectively. Then the ratio
q x1 / (x1-x2) k1 * c / k1 * dc / d is a rational number (for example, 1/2, 1/3, 5/7, 7/5, etc.).

2.2.2. From clause 2.1.4 it follows that the numbers T1 and T2 can be factorized, one of which k is the largest common factor, and r1 and r2, respectively, are integer residuals. Then
T1 / T2 r2 / r1 and
r1 * T1 r2 * T2 T0
The value of T0 can be considered as the period of placement of emitters and receivers having the same ordinates. The rays connecting these elements are parallel between themselves and the x axis. Therefore, such elements will be called opposing. Opposing elements have a coordinate
y * r1 * T1 * r2 * T2 * T0 * k * r1 * r2 where is an integer.

EXAMPLE 1. Let T2 1.2 cm 12 mm, T1 1.8 cm 18 mm, then T1 / T2 18/12 (6 * 3) / (6 * 2) 3/2. Here k 6 is the greatest common factor, r2 3, r1 2. The opposing elements have coordinates
y * 3 * 12 * 2 * 18 * 36. where 0, ± 1, ± 2,
2.3. The conclusion of the relationship between the periods T1 and T2 of the placement of the elements of the transmitting and receiving lines and discrete 6.

Based on the equation of the line passing through the points (x x1, y m * T1) and (x x2, y = n * T2), we can find the coordinates of the intersection points of the emission spectra emanating from the point x x2, yn * T2 * T0 + p2 * T2, where p2 0, ± 1, ± 2, with straight line x 0 and the spectrum of rays emanating from the point x x1, y m * T1 * T0 + p1 * T1, where p1 0, ± 1,
These coordinates will be
y (02) * T0 + p2 * T2 * q + j * T1 * (1-q)
y (01) * T2 + p1 * T1 * (1-q) + i * T2 * q where j, i 0, ± 1, ± 2. The difference between the nearest coordinates y (01) and y (02) will be equal to the interval
σ = k * F _min / d; where F _min is the minimum but non-zero value of the functional
F r2 * (j-p2) + c * r1 * (p2-i).

EXAMPLE 2. Let T1 18, T2 12, r1 = 2, r2 3, k 6. Then F _min for q equal to 1/3, 1/2 and 2/3 are respectively 1.1 and 2, and σ, respectively, are 2, 3, and 4. On the interval T0, L intervals σ fit, where L r1 * r2 * d / F _min
In our case, q 1/2, F _min 1, d 2 and σ = k / 2 T1 / 2 * r2 T2 / 2 * r1. and L 2 * r1 * r2
Example 3. Let k = 6, q = 1/2, r1 = 2, r2 = 3.

Then d 2, f _min 1 and σ 3. We determine the possible values of the periods T1, T2, T0 and the number of elements for the lines of receivers and transmitters having a length of 720 mm and σ3. These data are given in the table.

Claims (1)

A PHOTOELECTRIC MEASUREMENT SIZE MEASURER comprising a pulse generator, two pulse counters, a read-only memory, two decoders, a matrix of keys and amplifiers, a line of emitters and photodetectors, characterized in that, in order to increase accuracy and reliability by reducing the number of emitters and photodetectors in the line and alignment of the openings of the rulers, the rulers are made with periods of placement of emitters and photodetectors, determined by the formula
σ = T1 / (2 · r2) = T2 / (2 · r1) = k / 2,
where σ is the distance between adjacent beams;
r1 and r2 are the whole remainders of the decomposition of the periods T1 and T2 into factors;
k is the greatest common factor of T1 and T2,
a pulse generator, a first pulse counter on the first input, a permanent memory on the first output, a first decoder, a matrix of keys and a transmitting line are connected in series, a permanent memory on the first output, a second decoder, a matrix of amplifiers on the first output and a second pulse counter on the first input also connected in series, read-only memory at the second output is connected to pulse counters at the second inputs, and the receiver line is connected to the second input amplifiers matrix, the matrix of keys is intended for simultaneous inclusion of one emitter and receiver in each line.

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