RU2755534C1 - Apparatus for controlling dynamic state of vibrational technological machine and method for implementation thereof - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: apparatus consists of pneumatic cylinders, a compressor, vibration excitation tools, dynamic state control sensors, and a data recording and processing unit. Additionally, installed symmetrically on both sides are pneumatic cylinders and damper chambers, connected via throttles responsible for generating a control signal for adjusting the air pressure. The method includes the following operations: excitation of vibrations of the working member of the vibrational technological machine, registration of displacement of the coordinates of the vibrational technological machine. Units of elastic elements and damping chambers are placed symmetrically. Configuration of the parameters of distribution of the amplitudes of vibrations of the working member is ensured by general adjustment of the air pressure in the pneumatic cylinders.

EFFECT: increased operating efficiency of the equipment, ensured reliability and safety of operation thereof are achieved.

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Description

The proposed invention relates to vibration technology and can be used in the design and modernization of existing technological equipment.

Vibrations are widely used in various industries to perform transport operations, sort and classify bulk materials, harden the surfaces of parts in a working environment that performs periodic shaking, in the manufacture of foundry trusses, etc. In many cases, technological machines are represented by vibration tables of various designs, vibrating screens, feeders, bins , that is, they are implemented in constructive and technical forms, suggesting the possibility of the presence of working bodies that create certain, so-called vibration fields. The interaction of working environments, individual parts with each other, the coordination of the actions of units and equipment devices requires the development of methods for assessing, monitoring, adjusting and forming the distribution of the vibration amplitudes of the points of the working bodies over their entire functional space.

Excitation of vibrations of the working bodies of vibration stands is realized, as a rule, by the corresponding vibrators, most often of the inertial type, which create impacts in local zones and small variable possibilities of changing the spatial distributions and varieties of connectivity of the movement of the fragments of the vibration table.

In the course of the patent search, a number of analogous inventions were identified.

Known invention [Antipov V.I., Antipova R.I., Koshelev A.V., Dentsov N.N. "Vibration conveying machine", 2532235 C2, IPC V06V 1/00, priority 27.10.2014], which is a vibratory conveying machine with a working body connected by an elastic connection to the reactive part, carrying a means for communicating resonant unidirectional vibrations, and shock absorbers of low stiffness, characterized in that the means for communicating resonant unidirectional vibrations is made in the form of at least a pair of identical parametric vibration exciters mounted on the reactive part of the machine, installed with the possibility of rotation of rotors of inertial elements in opposite directions in vertical planes and driven in rotation from independent electric motors, and the resonant frequency of the means for communicating resonant unidirectional oscillations is determined from the relations ω = λ ₁ + λ ₂ , λ ₁ = ν⋅ω, 0 <ν <1, where ω is the average value of the partial angular velocities of the rotors, λ ₁ is the effective natural frequency of swinging pendulums rotors are inertial th elements, λ ₂ = √ (C / Мпр) - partial natural frequency of the working body, corresponding to the antiphase form of unidirectional free vibrations, Мпр = М ₁ М ₂ / (М ₁ + М ₂ ) - reduced mass, С - elastic bond stiffness, M ₁ is the mass of the working body, M ₂ is the total mass of the reactive part of the machine.

The disadvantages of this analogue include the lack of control over the dynamic state of the vibration machine.

Known vibration machine [Serga G. V., Reznichenko S.M. "Vibrating machine for pre-sowing seed treatment", 2585476 C1, IPC А01С 1/00, priority 27.05.2016], intended for pre-sowing seed treatment, containing a grinding drum, the inner surface of which is covered with a layer of rubber, with an unloading window, working body, dispenser hopper , an unloading chute installed elastically on the base, characterized in that the grinding drum, the inner surface of which is covered with a layer of rubber, is made of conical, multi-pass, screw and is assembled from guide elements made of three or more twisted along a helical line in the longitudinal direction relative to the longitudinal axis and bent along a helical line in the transverse direction on a mandrel in the form of a paraboloid of rotation of strips made with lateral edges of a convex curvilinear shape with gaps, and described by curves of various orders and degrees of curvature, while gaps in the form of helical blades are formed along the entire length inside the grinding drum, and along the entire length of the cut The shaft drum is equipped with a conical spring with a flat section of the turns and with a device for changing the pitch of the turns by stretching or compressing the spring.

The disadvantages of this invention are the lack of control and stabilization of the dynamic state of the vibration machine.

One of the analogs is a vibrating device for sieving and feeding material [ZHU Xingliang (CN) "Vibrating device for sieving and feeding material", 2567250 C2, IPC V07V 1/28, V07V 1/42, priority 10.11.2015], performed with one shaft and with the possibility of changing the trajectory of movement, contains a vibration box, a lower support plate, a vibration spring, a vibration shaft mounted on the vibration box. The vibration spring is installed between the vibration box and the bottom support plate. On both sides of the vibrating box, a plurality of groups of rod assemblies are installed that limit the trajectory of movement and are located obliquely. Each group of rod nodes limiting the trajectory of movement contains two rod assemblies that limit the trajectory of movement, which are located symmetrically on both sides of the vibration box, and both ends of each rod unit that limits the trajectory of movement are pivotally attached to the vibration box and the lower base plate.

The disadvantages of this invention include the complexity of the design, as well as the lack of a device for changing the dynamic state.

The prototype is taken as a method and device for controlling and changing the dynamic state of the vibration protection system and a device for its implementation [Eliseev S.V., Eliseev A.V., Bolshakov RS, Nikolaev A.V., Vyong K.Ch., Mironov A .WITH. "Method of controlling and changing the dynamic state of the vibration protection system and a device for its implementation", 2696062 C1, IPC F16A 15/04, F16F 7/08, B60N 2/54, priority 07/30/2019], according to which the vibration protection system is supplied with additional elements that provide adjustment and control of its dynamic state using sensors and a block for information processing and control of these processes, characterized in that the formation of the required dynamic reactions is carried out by changing the reduced stiffness of the generalized spring. The device differs in that the dynamic state of the vibration protection system is controlled by changing the reduced stiffness of the generalized spring, consisting of a connected helical non-self-braking mechanism and a parallel introduced conventional spring and a pneumatic cylinder connected in series with them, the stiffness of which is regulated by a compressor and a controlled throttle to relieve excess pressure.

The main disadvantages of the prototype include the presence of an excessive number of additional elements responsible for monitoring the dynamic state.

The objective of the present invention is to control the dynamic state of a vibrating technological machine by adjusting the parameters of elastic blocks and associated damper chambers by changing the diameters of the controlled chokes.

A device for controlling the dynamic state of a vibration technological machine, consisting of pneumatic cylinders, a compressor, vibration excitation means, dynamic state control sensors, a data recording and processing unit, characterized in that additionally pneumatic cylinders and damper chambers are installed symmetrically on both sides, connected through throttles responsible for formation of a control signal to regulate air pressure.

A method for controlling the dynamic state of a vibration technological machine, including excitation of vibrations of the working body of a vibration technological machine and registration of the displacement of the coordinates of movement of a vibration technological machine according to claim the body is provided by the general regulation of air pressure in the pneumatic bellows.

The essence of the invention is illustrated by drawings.

FIG. 1 shows a schematic diagram of a vibratory technological machine with a device for controlling the dynamic state of the working body, containing a support surface 1, rigid damping chambers 2, 8, compressors 3, 7, communications 4, 6, 9, 11, 20, 22, a registration and processing unit information 5, controlled throttles 10, 15, 17, 19, 21, rubber-cord pneumatic shock absorbers 12, 23, sensors (vibrometers) 13, 24, working body 14, vibration exciter 14, 14 'pipeline 16, 18.

FIG. 2 shows the design diagram of a vibrating technological machine.

FIG. 3 shows a block diagram of a dynamically equivalent automatic control system.

The invention works as follows.

The proposed device is a mechanical oscillatory system with two degrees of freedom with a working body in the form of an extended solid body with a mass M and a moment of inertia J, resting on two special elastic-pneumatic supports of two chamber type, connected by pipelines 16, 18 with an adjustable throttle 17.

параметры колебаний рабочего органа 14 измеряются с помощью виброметров 13, 24, установленных в тт. A, F, что обеспечивает, в целом, необходимые движения рабочего органа.The operation of the invention is carried out by a mechanical oscillatory system, consisting of a rigid body (14) with a mass M (center of mass at point O) and a moment of inertia J, resting on surface 1 with the help of two pneumo-elastic blocks, each of which, in turn, consists of from two parts: rubber-cord pneumatic shock absorbers, respectively, 12, 23, combined with damping chambers 2, 8 using controlled throttles 10 and 21; while the damper chambers 2 and 8 have additional controllable throttles 15 and 19, through which the damper chambers are connected by pipelines 16, 18, through the choke 17; the dynamic state of the system is formed by an inertial vibration exciter 14 ', displaced relative to the center of mass (m. O) by an arm length

the parameters of vibrations of the working body 14 are measured using vibrometers 13, 24, installed in tt. A, F, which provides, in general, the necessary movements of the working body.

A device for controlling the dynamic state of the working body of a vibration machine, consisting of an adjustable and controlled pneumatic system using throttles that regulate the flow of air between the elastic and damper cavities of pneumatic blocks 12, 23, as well as damper blocks between themselves using throttles 10, 21 through pipelines 16, 18 controlled by the throttle 17, having a system for maintaining constant parameters of the air in the chambers through the compressors 3, 7, connected with the damper chambers 2 and 8, providing coordinated actions of the controlled chokes through the information received from the command unit 5, which implements the dynamic state control algorithm on the basis of receiving information from sensors 13, 24 through communications 11, 22, as well as communication links 4, 6, 9, 20, which ensure the operation of the system as a whole by opening and closing the throttles according to the signals of the command unit, ensuring the operation of the system as a whole by opening and closing chokes by signal am of the command block, which provides the necessary ratio of the amplitudes of oscillations in points A, B, which determine the parameters and structure of the vibration field when excited by the vibrator.

Theoretical justification

The design diagram of a vibrating technological machine with a multifunctional control system is shown in Fig. 2. A solid body of mass M has a center of gravity at point O and has a moment of inertia J relative to this point. The solid body rests on two pneumo-elastic blocks, each of which consists of two chambers: a working (volume V ₁ ) and a damper - volume V ₁₀ ... The chambers are interconnected by an adjustable throttle. The second block with parameters V ₂ and V _{20 is} similarly arranged. Throttle devices connecting the working and damping chambers have viscous damping properties, which is taken into account by the coefficients of viscous friction b ₁ and b _2, respectively.

Damping chambers with volumes V ₁₀ and V _{20 are} connected to each other through a large diameter pipeline, which has a controlled damper with a damping coefficient b ₃ . Thus, the dynamic state of the system (Fig. 2) can be controlled in several versions (b ₁ = 0, b ₂ ≠ 0, b ₃ ≠ 0; b ₁ ≠ 0, b ₂ = 0, b ₃ ≠ 0; b ₁ = 0, b ₂ = 0, b ₃ ≠ 0; b ₁ → ∞, b ₂ = 0, b ₃ = 0, etc.).

(т. E - точка приложения гармонической силы возбуждения колебаний).The construction of a mathematical model of the system is carried out taking into account the use of the following relations:

(i.e., E is the point of application of the harmonic force of excitation of oscillations).

Mathematical modeling in this case can be built on the basis of structural mathematical modeling, within which the original mechanical oscillatory system is compared with a dynamically equivalent structural diagram of an automatic control system (in accordance with [1, 2], the technology of operational Laplace calculus is used).

и

полагая, что объему воздуха V₁ в резинокордном блоке определяет жесткость упругого элемента как k₁; соответственно для демпферной камеры имеем k₁₀. Аналогично по координате

твердое тело, таким образом, будет опираться на элемент с приведенной жесткостью1. Consider the case when b ₃ = 0, b ₁ ≠ 0, b ₂ ≠ 0, which allows us to display in operator form the reduced rigidity of the system in the coordinates

and

assuming that the volume of air V ₁ in the rubber-cord block determines the stiffness of the elastic element as k ₁ ; accordingly, for the damper chamber we have k ₁₀ . Similarly for the coordinate

the rigid body, thus, will rest on the element with reduced stiffness

имеем соответственноby coordinate

we have respectively

where p = jω is a complex variable (j = √-1); the <-> icon above a variable means its Laplace image [1, 2].

приложенной в т. Е на расстоянии

от центра масс (т. О, фиг. 2), уравнение движения в операторной форме принимает вид2. In the absence of communication (in the form of a pipeline) between pneumatic blocks k _pr1 (p) and k _pr2 (p) and the action of a harmonic force

applied in T. E at a distance

from the center of mass (point O, Fig. 2), the equation of motion in operator form takes the form

In equations (3), (4), the following designations are adopted:

We believe that expressions (3), (4) can be used as a mathematical model (more precisely, its structural version) to construct a structural diagram of a dynamically equivalent automatic control system, as shown in Fig. 3.

The transfer function of interpartial communication has the form

Let's make intermediate transformations and get that

After substitution of (1), (2) in (7), the expression takes the form

The expression can be reduced to fractional rational form with 4th order polynomials in the numerator and denominator.

предопределяет возможности управления распределением амплитуд колебаний точек рабочего органа по его длине, то есть осуществлять формирование структуры вибрационного поля и управление, таким образом, динамическим состоянием вибрационной технологической машины.Similarly, other connections can be introduced into consideration and use, for example, under the condition b ₁ ≠ 0, b ₂ ≠ 0, b ₃ ≠ 0, or b ₁ ≠ 0, b ₂ ≠ 0, b ₃ → ∞ and others. Algorithm for controlling the ratio of coordinates

predetermines the possibility of controlling the distribution of the vibration amplitudes of the points of the working body along its length, that is, to carry out the formation of the structure of the vibration field and control, thus, the dynamic state of the vibration technological machine.

In particular, for all open chokes, when b ₁ = 0, b ₂ = 0, b ₃ = 0, the original system (more precisely, the design diagram of the technological machine is transformed to the form as shown in Fig. 2, but the reduced stiffness of the elastic elements will have different values). In this case, the system takes on a simplified configuration, where the working body of the machines, like a rigid body, rests on elastic elements (quasi-springs) with stiffnesses

имеем соответственноby coordinate

we have respectively

The capabilities of the control system in the formation of the dynamic states of the working bodies can be significantly expanded using chokes 15, 19 (Fig. 1) with damping coefficients b ₄ and b ₅ in the damping chambers 8 and 2, respectively.

Thus, in the tuning operations, the parameters b ₁ ÷ b ₅ can be used, each of which, in addition to the values of the ordinary order, can also take extreme values equal to zero or infinity.

Ultimately, the control system of the shaker, with appropriate preliminary preparation, can obtain a preselected program, which is implemented by the microprocessor in the process of working out a given mode.

List of sources used.

1. Eliseev S.V., Artyunin A.I. Applied theory of oscillations in problems of dynamics of linear mechanical systems. Novosibirsk: Nauka, 2016.459 p.

2. Eliseev SV. Applied system analysis and structural mathematical modeling (dynamics of transport and technological machines: connectivity of movements, vibrational interactions, linkages): monograph - Irkutsk: IrGUPS, 2018 .-- 692 p.

Claims (2)

1. A device for controlling the dynamic state of a vibrating technological machine, consisting of pneumatic cylinders, a compressor, vibration excitation means, dynamic state control sensors, a data recording and processing unit, characterized in that additionally pneumatic cylinders and damping chambers are installed symmetrically on both sides, connected through throttles, responsible for the formation of a control signal to regulate air pressure. 2. A method for controlling the dynamic state of a vibration technological machine, implemented by the device according to claim 1, including excitation of vibrations of the working body of a vibration technological machine and registration of the displacement of the coordinates of movement of a vibration technological machine, characterized in that blocks of elastic elements and damping chambers are symmetrically placed and parameters are set the distribution of the vibration amplitudes of the working body is provided by the general regulation of the air pressure in the pneumatic bellows.

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