RU2773825C1 - Apparatus for forming vibrational movement of the working medium - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: apparatus for forming vibrational movement of the working medium comprises a main unit in the form of an elongated solid body with a mass and a moment of inertia, and an air pumping system with a compressor and controlled throttle valves. The main unit is supported by elastic elements in the form of screw and pneumatic springs with a property of adjustment within the scope of capabilities of the control system, vibration sensors, information processing unit. The apparatus is equipped with triangular units interconnected by hinges. Each pair of triangular units is connected with each of the opposite ends of the apparatus. Some of the triangular units are hinged to the support surface, the others are hinged to the working body. The triangular units are equipped with loads configured to change the mass or position thereof on the levers of the corresponding triangular units.

EFFECT: possibility of pre-adjusting and maintaining the set parameters of the technological process.

1 cl, 4 dwg

Description

The present invention relates to mechanical engineering associated with the development of new types of process equipment using the effects of vibrational interaction of machine elements and process media.

In recent decades, vibration technology machines have found application and are widely used in many production processes: in the construction industry, in the mining industry, in the construction of railways, highways, in the chemical industry, etc.

Vibratory technological processes implement the vibrational movement of bulk mixtures, their classification, and are used to feed and orient parts in automated production of mechanical engineering enterprises. Vibration technologies make it possible to solve the problems of hardening the surfaces of parts of complex shapes in the vibration fields of loose and granular media.

The development of the scientific foundations of vibration technologies was reflected in the works of domestic scientists Blekhman I.I., Babichev A.P., Goncharevich I.F., Weisberg L.A., Bykhovsky I.I., Poturaev V.N. and others. The features of the formation of vibration fields by the working bodies of vibration technological machines have been studied and studied in sufficient detail, taking into account the specific conditions for excitation of oscillations, the possibilities of assessing, forming and controlling the dynamic states of the working bodies in the form of extended solid bodies with mass and moment of inertia and performing a plane motion or spatial motion under the action of a periodic perturbation.

At the same time, the tasks of the practical development of innovative technologies require the search and development of new methods and means for the formation and control of the dynamic states of the working bodies and the working processing environments interacting with them.

In this regard, of particular interest are the possibilities of organizing the processes of interaction of working media with parts in spatial conditions, which can be created by working bodies of a special design, consisting of several interacting blocks controlled in a certain way.

In the process of patent search, a number of inventions-analogues were revealed.

An invention is known [Serga G.V., Reznichenko S.M. "Vibrating machine for pre-sowing seed treatment", 2585476, IPC B28V 11/08, E01C 19/42, priority 11/27/2005], containing a grinding drum, the inner surface of which is covered with a layer of rubber, with an unloading window, a working body, a hopper dispenser, unloading tray 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 conical, multi-threaded, screw and mounted from guide elements made of three or more twisted along a helical line in the longitudinal direction relative to the longitudinal axis and curved along a helical line in the transverse direction on a mandrel in the form of a paraboloid of rotation of strips made with side edges of a convex curvilinear shape with laps, and described by curves of various orders and degrees of curvature, while along the entire length inside the grinding drum laps are formed in the form of helical blades, and along the entire length of the grinding drum is mounted conical I am a spring with a flat coil section and with a device for changing the pitch of the coils by stretching or compressing the spring.

The analog under consideration does not provide for control and adjustment of the dynamic state of the vibrational technological machine, and there is also no mathematical description of the dynamic effects that occur during operation.

There is a method for setting the dynamic state of a vibrational technological machine and a device for its implementation [Eliseev S.V., Bolshakov R.S., Eliseev A.V., Mironov A.S., Nikolaev A.V. “Method for setting the dynamic state of a vibrational technological machine and a device for its implementation”, 2718177, IPC F16F 15/02, priority 03/31/2020], according to which vibrations of the working body of a vibrational technological machine are excited and the displacement of movement coordinates is recorded. An additional vibration exciter and a pneumatic elastic element are introduced into the system. By changing the position of the pneumatic elastic element relative to the center of mass of the element system and the pressure in it, the reduced stiffness of the system is regulated. The device contains a solid body on elastic supports, a vibration exciter, sensors and an additional adjustable elastic element. Additional elastic element is made in the form of a pneumocylinder. The automatic tuning system regulates the parameters of the air spring. It is possible to adjust the dynamic state of the object by changing the reduced stiffness of the system.

The disadvantages include the presence of a complex control system to obtain the necessary modes of operation.

A vibration machine is known [Emelianenko N.G., Metelev A.V., Kuznetsov V.V. "Vibrating Machine", 2108171, IPC B06 B 1/18, priority 03/10/1998], containing the working body is connected to the piston rods installed in the cylinders. Cylinders are divided into hydro-cavities and pneumatic cavities. The communication of the pneumatic cavities with the pneumatic line and the discharge of compressed gas from them is carried out by a distributing device. In a separate block, communicated with the hydrocavities, elastic gas-filled bodies are placed, preferably in the form of toroidal automobile pneumatic chambers. The latter are communicated with each other and the pneumatic line. The pistons and hydraulic cavities of the cylinders are separated by membranes. Due to the placement of pneumatic chambers in a separate block, the conditions of installation and operation are improved. The communication of the pneumatic chambers with each other and with the pneumatic line ensures the adjustment of the rigidity of the elastic system of the vibrator. Due to the exclusion of fluid overflow from the hydraulic cavities into the pneumatic cavities, the pistons in the cylinders can be installed with gaps, as a result of which the durability and reliability of the vibrator drive is increased.

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

For the prototype takes the invention [Mamaev L.A., Kononov A.A., Gerasimov S.N., Bublik S.S. “Working body in the form of a bar with vibration sectors”, 2 264 912, IPC B28B 11/08, E01C 19/42, B61F 3/10, priority 11/27/2005], containing the Working body in the form of a bar with vibration sectors, having the ability to perform reciprocating wave motion along a trajectory resembling a generatrix of a sea wave extending from the middle of one cavity to the middle of the second, characterized in that there are sectors on the working surface of the beam that can perform reciprocating motion in a vertical plane, and the sectors are divided into two groups , each of which has the ability to move in opposite directions, transferring the vibration effect to the surface to be treated without tearing off the edge of the main working surface of the beam from it.

The disadvantages of the prototype include the complexity of the design of the working body and the lack of devices for setting the required modes of operation.

The objective of the invention is the formation of the dynamic state of the vibrational technological machine by changing the parameters of adjustable structural elements.

A device for generating a vibrational movement of the working medium, characterized in that it contains the main unit in the form of an extended solid body having a mass and a moment of inertia, based on elastic elements in the form of helical and pneumatic springs, which have the property for settings and within the capabilities of the control system, vibration sensors , an information processing unit, an air pumping system with a compressor and controlled throttles, while the device is pivotally connected to the support surface, and the others to the working fluid, and the triangular blocks are equipped with weights made with the possibility of changing their mass or position on the levers of the corresponding triangular blocks.

In FIG. 1 shows a schematic diagram of a vibration process machine with a complex working body, containing a support surface 1, a compressor 2, a control unit 3, an information processing unit 4, air ducts 5, 30, damping chambers 6, 29, throttles 7, 8, 27, 28, pneumoelastic chambers 9, 26, springs 10, 25, triangular blocks 11, 14, 21, 24, levers 12, 23, mass-inertial elements 13, 15, 20, 22, vibration sensors 16, 19, working body 17, vibrator 18, communications 31, 32, 33, 34, 35, 36.

In FIG. 2 shows the design scheme of a technical object in the form of a mechanical oscillatory system with two degrees of freedom with a composite working body.

In FIG. 3, a, b shows the schematic diagrams of the location of the velocities of the points along the coordinates y ₁ and y ₂ .

In FIG. 4 shows a structural mathematical model (structural diagram) of the original system according to the design scheme in FIG. 2.

The invention works as follows.

The present invention relates to those areas of mechanical engineering that are associated with the development of methods and means to increase labor productivity, improve product quality and create safe operating conditions for equipment that implement vibration technologies. The invention is implemented by a mechanical oscillatory system consisting of a working body in the form of a solid body with a mass and a moment of inertia that performs movements characteristic of systems with two degrees of freedom.

The technological object contains a working body 17, which is a connection of the main working body, to which in TT. A ₃ , B ₃ join two triangular blocks 14, 21; at these points, the blocks are connected through swivel joints with the main part of the working body, the position of which is determined by the coordinates y ₁ and y ₂ ; in turn attached triangular blocks 11, 24 tt. A ₁ , B ₁ are connected to the levers 12, 23 connected through swivel joints in tt. A, B with support surface 1.

Working body in vols. A, B rests on elastic elements 10, 25 with stiffness coefficients k ₁ and k ₂ ; in turn, the elastic elements are connected to the working body 17 in TT. A ₄ , B ₄ .

Parallel to the elastic elements 10, 25 with stiffnesses k ₁ and k ₂ , pneumoelastic blocks are installed in the system, having reduced stiffnesses k _pr1 and k _pr2 , which operate in parallel with metal helical springs 10, 25.

Each of the pneumoelastic elements is connected in the upper part with the working body 18; the lower part is installed on the supporting surface 1.

Pneumatic springs consist of pneumoelastic chambers 9, 26 with volumes V ₁ , V ₁₀ (pneumoelastic cylinders), based on damping chambers 6, 29 in the form of a rigid cylinder with volumes V ₂ and V ₂₀ , respectively. Inside the air mounts there are throttles 8, 27, which can change their cross section and create energy dissipation effects; their parameters of reduced viscous friction coefficients are denoted as b ₁ and b ₂ , respectively. In the section “Theoretical substantiation of the system operation”, more detailed data on the operation of the air mounts will be given.

Pneumatic cylinders 9, 26 are pumped by compressor 2 through air ducts 5, 30 and controlled throttles 7, 28. The system is excited by an inertial vibrator 18 installed in the lower part of the working body 17; the dynamic state of the system is recorded by vibration sensors 16, 19 connected through communications 31, 34 with the information processing unit 4.

Setting the vibrational technological complex (Fig. 1) to the appropriate dynamic state is ensured by selecting the excitation parameters and can be adjusted by changing the masses of weights m ₁ , m ₂ , m ₁₀ , m ₂₀ 13, 15, 20, 22 or by changing the position of the weights on the levers 12 , 23 (variation of segment lengths).

A feature of the invention is the possibility of creating specific modes in the formation of vibrational fields of the working body, consisting of three movable sectors moving in a two-coordinate system of plane motion. This allows, when organizing the movement of the working processing medium, to create effective three-dimensional movements with the simultaneous formation of certain forms of spatial displacements of the technological environment as a whole, and to process parts of complex shape due to continuous tossing.

The setting of the technological complex can be carried out by varying the parameters of the pneumoelastic suspensions, using controlled throttles and a compressor to provide the necessary compressed air parameters.

Theoretical substantiation of the system operation

1. The present invention as a technical object is a technical system, the schematic diagram of which is shown in Fig. 1. The design scheme of the technical object according to FIG. 1 is a mechanical oscillatory system with lumped parameters with two degrees of freedom. It is assumed that the calculation scheme (physical model of the system) makes small oscillations relative to the position of static equilibrium or steady motion, which is considered in the coordinate system y ₁ , y ₂ associated with a fixed basis.

The working body of the technological machine is made in the form of a mechanical closed circuit, in the structure of which a solid body with mass M and moment of inertia J occupies a central position. The working body is based on lever mechanisms (levers located in the swivel, designated as TT. - A ₁ - A ₄ , B ₁ -B ₄ ). In tt. A ₃ and B ₃ the working body has contacts with elastic elements with stiffness k ₁ and k ₂ ; parallel to these elements, controlled pneumoelastic supports with damper chambers are used.

The design scheme of the original system (Fig. 1) is shown in Fig. 2 and is a mechanical oscillatory system with two degrees of freedom, the structure of which has a set of additional dynamic links implemented by lever mechanisms.

The dynamics of the original system (Fig. 2) is quite complex, but its consideration can be simplified by constructing a linear mathematical model, taking into account the smallness of the oscillations of the elements relative to the position of static equilibrium.

The elements of the system, in addition to the working body, having a mass M and a moment of inertia J, also have mass-inertial properties in the form of concentrated masses m ₁ , m ₂ , m ₁₀ , m ₂₀ in tt. A ₂ , B ₂ , A ₄ , B ₄ .

The system has sources of external excitation of oscillations of the working body in the form of an external harmonic force Q(t) applied in t. O - the center of mass; the position of the center of mass relative to the ends of the working body (mm. A ₃ , B ₃ ) with shoulder lengths l ₁ , l ₂ .

The motion of the system is considered using coordinate systems y ₁ , y ₂ , as well as y ₀ , ϕ. There are the following relations between the coordinates

where

To build a mathematical model, the Lagrange method [1] is used, which is associated with the construction of expressions for the kinetic and potential energies of the system, which requires determining the velocities of the elements m ₁ , m ₂ , m ₁₀ and m ₂₀ . The desired speeds on the design scheme (Fig. 2) are indicated respectively: for

,

,

,

производится с использованием представлений о мгновенных центрах скоростей, что требует определенных геометрических построений. Необходимые данные приводятся на схемах (фиг. 3, фиг. 4). Нужная информация о конструктивных параметрах (углы β₁, β₂, β₃ и γ₁, γ₂, γ₃), длины звеньев l₀₁, l₀₂, l₀₃, l₁₀, l₂₀, l₃₀, l₄₀ и др. параметры являются исходными и определяются, исходя из конструктивно-технических соображений, связанных с проектными решениями.Determination of speeds

,

,

,

is produced using the concepts of instantaneous centers of velocities, which requires certain geometric constructions. The necessary data are given in the diagrams (Fig. 3, Fig. 4). The necessary information about the design parameters (angles β ₁ , β ₂ , β ₃ and γ ₁ , γ ₂ , γ ₃ ), link lengths l ₀₁ , l ₀₂ , l ₀₃ , l ₁₀ , l ₂₀ , l ₃₀ , l ₄₀ , etc. .parameters are initial and are determined on the basis of structural and technical considerations associated with design solutions.

Using auxiliary design schemes (Fig. 3, Fig. 4) on the basis of known design and technical data, the ratios are determined

Taking into account the above, the expression for the kinetic energies of the system takes the form

2. To determine the potential energy of the system, it is necessary to take into account detailed representations of pneumoelastic blocks.

As noted earlier, the pneumoelastic block (pneumospring) consists of a pneumoelastic element of a balloon type with a chamber volume V ₁ , which forms the local stiffness (of an equivalent spring) k ₀₁ . The second air spring assembly forms the damper chamber; the shell of such a chamber is a rigid cylindrical shell of volume V ₂ , which forms the equivalent local stiffness k ₀₂ . Both mentioned chambers are connected through a controlled petal throttle, which creates conditions for energy dissipation, which can be displayed as a damping connecting link with a damping coefficient b.

The general scheme of the pneumoelastic block can be represented by a series connection of two constituent elements

If b ₁ → 0, then

When b ₁ → ∞ - k _pr1 =k ₀₁ .

The features of the dynamic properties of such elastic elements will be considered below, but in a more convenient operator form. Thus, the expression for the potential energy of the system can be represented as

where

3. Using the expressions for the kinetic and potential energies, we write a number of auxiliary relations for a system with two degrees of freedom:

The mathematical model of the original object according to the calculation scheme shown in figure 2 can be represented by a system of two ordinary differential equations with constant coefficients in the time domain

Equations in the time domain (11), (12) can, after the Laplace integral transformations under zero initial conditions, be presented in operator form [1]:

where p=jω is a complex variable (J=√-1), the <-> sign above the variable means its image according to Laplace [3].

The system of equations (13), (14) in operator form can be interpreted by a block diagram of a dynamically equivalent automatic control system, as shown in Fig. 4 [2].

, которые одновременно действует на два входа системы:Using the block diagram (Fig. 4), it is possible to construct the transfer functions of the system for a given force perturbation

, which simultaneously acts on two inputs of the system:

where

is the frequency characteristic equation of the system.

4. Estimation of possible dynamic properties. The mechanical oscillatory system under consideration consists of two partial blocks interconnected by a link of interpartial bonds; this link reflects the inertial nature of the dynamic links between the partial blocks.

With certain combinations of inertial parameters of the system, partial constraints can be set to zero; in this case, partial blocks can be set to zero; in this case, the partial units operate offline.

In general, the system has two frequencies of natural oscillations, at which it is possible to excite resonant (b ₁ =0, b ₂ =0) or near-resonance modes (b ₁ ≠0, b ₂ ≠0).

The analysis shows that at certain frequencies, which coincides with the “zeroing” of the numerators of the transfer functions W ₁ (p) and W ₂ (p), it is possible to implement dynamic vibration damping modes, which allows you to create vibration fields on the working body (that is, the distribution of oscillations of the points of the working body) of various forms of movement of the elements of the system, providing spatial forms of interaction of loose technological media with the product processed on the working body.

5. An approach based on the use of the transfer function of interpartial connections has great potential in assessing the dynamic state of a vibration technological machine, in terms of choosing and evaluating dynamic modes.

и

. Если W₁₂(p)=i=1, то рабочий орган совершает только поступательные вертикальные вибрационные движения. В свою очередь, при i=-1 рабочий орган совершает только угловые колебания при условии, что у₀=0 (то есть центр масс является неподвижным).Usually W ₁₂ (p) is considered as connections of motion along the coordinates

and

. If W ₁₂ (p)=i=1, then the working body performs only translational vertical vibrational movements. In turn, when i=-1, the working body performs only angular vibrations, provided that y ₀ = 0 (that is, the center of mass is motionless).

The trapezoidal shape is the distribution of the amplitudes of oscillations of points along the length of the working body, if i>1 or i<1. In this case, the working body has a so-called center of oscillation, relative to which the working body makes angular oscillations.

и

) узел колебаний совпадает с «обнуляющейся» координатой.In the modes of dynamic vibration damping (

and

) the oscillation node coincides with the "resetting" coordinate.

The presence in the system of a pneumoelastic block with a controlled throttle (b ₁ , b ₂ ) makes it possible to avoid a sharp increase in the oscillation amplitudes at frequencies close to the resonant ones.

The choice and adjustment of the vibrational technological complex is carried out by varying the mass values of the weights m ₁ , m ₂ , m ₁₀ and m ₂₀ and the capabilities and lengths of the arms of the levers l ₁₀ and l ₂₀ , which forms the values of the tuning mass inertia coefficients a _I , a _II , a ₁₀ , and ₂₀ . In addition, if necessary, the possibilities of throttling the channels of the elastic and damper chambers of the pneumoelastic supports can be used.

To maintain the parameters of the suspension and its regulation, the system is equipped with a compressor.

The dynamic state of the vibration technological complex is controlled by appropriate sensors, has a system for collecting and processing information in accordance with the regulations of the technological process to obtain various dynamic modes, including those that can be used when processing parts of complex shape.

Sources of information

1. Lurie A.I. Operational calculus and its applications to problems in mechanics. M.; L.: Mrs. Publishing house of tech.-theor. lit., 1950. - 431 p.

2. Eliseev S.V., Eliseev A.V. Theory of oscillations. Structural mathematical modeling in problems of dynamics of technical objects. Cham: Springer Nature Switzerland AG, 2019. 521 p.

Claims (1)

A device for forming a vibrational movement of the working medium, characterized in that it contains the main unit in the form of an extended solid body having a mass and a moment of inertia, based on elastic elements in the form of helical and pneumatic springs, having the property of subtuning within the capabilities of the control system, vibration sensors, unit information processing, an air pumping system with a compressor and controlled throttles, while the device is equipped with triangular blocks pivotally connected to each other, each pair of which is connected to each of its opposite ends, while one of the triangular blocks is pivotally connected to the supporting surface, the others to the working body, and the triangular blocks are equipped with weights, made with the possibility of changing their mass or position on the levers of the corresponding triangular blocks.

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