Vibrating conveyor

Abstract

The utility model relates to devices for vibratory transportation, namely to vibratory conveyors, and can be used for transporting bulk materials in the food, chemical, construction and mining industries. The technical result of the utility model is to increase the energy efficiency and operational stability of a vibratory conveyor. This technical result is achieved by the fact that in the vibratory conveyor, the vibratory drive is implemented in the form of an oscillatory motion electric motor, including a stator with an excitation winding, a rotary anchor with a resonant tuning spring and an additional mass located in a guide, connected to the rotary anchor driver by means of a cylindrical spring, the stiffness of which is determined by the expression:, where c2 is the stiffness of the cylindrical spring, N / m; m is the additional mass, kg; ω is the angular frequency, equal to twice the frequency of the power supply network, rad / s.

Description

[0001] The utility model relates to devices for vibration transportation, namely to vibration conveyors, and can be used for transporting bulk materials in the food, chemical, construction and mining industries.

[0002] A vibratory multi-drive conveyor is known, comprising a load-bearing chute mounted on a fixed frame using inclined flat springs, and vibratory drives arranged sequentially along the conveyor, providing directed oscillations of the chute. The load-bearing chute is made of individual sections arranged with gaps relative to one another, which are covered by intermediate elements made of spring steel (Russian Federation Patent No. 2494949, IPC B65G 27 / 04, published 10.10.2013).

[0003] The disadvantage of this analogue is that its design does not provide effective action on the transported material to prevent it from sticking to the work surface due to the lack of a flexible bottom with an individual drive. Furthermore, the use of vibration drives without the ability to resonate results in increased energy consumption and does not ensure stabilization of the vibration amplitude when the process load changes.

[0004] A vibrating conveyor is known, comprising a frame, a chute mounted on the frame via elastic elements, a vibrating drive, and a control system. In this conveyor, the chute bottom is flexible and kinematically connected to the vibrating drive to transmit vibrations (Russian Federation Patent for Utility Model No. 45722, IPC B65G 27 / 24, published May 27, 2005).

[0005] The disadvantage of this analogue is that the bottom and the tray are driven by the same drive, this limits the ability to adjust the vibration modes (frequency and amplitude) for the tray and the bottom separately, which reduces the effectiveness of the fight against material sticking and does not allow the creation of optimal wave effects in the transported medium.

[0006] The closest technical principle to the claimed utility model is a vibrating conveyor. The conveyor comprises a chute mounted on a frame by elastic elements, a vibrating drive, and a control system. The chute bottom is flexible, has perforated holes, and is kinematically connected via an elastic stop to an additional electromagnetic drive mounted on the inner surface of the chute. The control system is electrically connected to the drives via feedback sensors (Patent for Utility Model of the Russian Federation No. 192829, IPC B65G 27 / 24, published October 2, 2019).

[0007] A drawback of the prototype is that the chute's vibratory drive is not optimized for resonant operation with high energy efficiency. Using a standard electromagnetic drive does not allow for flexible tuning of the system to the resonant oscillation frequency, which can lead to increased energy consumption and a decrease in oscillation amplitude with changes in the mass of the transported material (process load). This reduces the efficiency of material transport and drying.

[0008] The technical result of the utility model is to increase the energy efficiency and operational stability of the vibrating conveyor.

[0009] The specified technical result is achieved in that in a vibrating conveyor, including a vibrating drive and a control system, a tray mounted on a frame by means of elastic elements, the perforated bottom of which is made flexible and kinematically connected through an elastic limiter with an additional electromagnetic drive secured to the inner surface of the tray, and the control system is electrically connected to the drives by means of feedback sensors, wherein the vibrating drive is made in the form of an oscillatory motion electric motor, including a stator with an excitation winding, a rotary anchor with a resonant tuning spring and an additional mass located in the guide, connected to the leash of the rotary anchor by means of a cylindrical spring, the rigidity of which is determined by the expression:

[0010] c2=mω 2 (1),

[0011] where c2 is the stiffness of the coil spring, N / m;

[0012] m - additional weight, kg;

[0013] ω - angular frequency, equal to double the frequency of the power supply network, rad / s.

[0014] The vibration drive is designed as an oscillating electric motor, comprising a stator with an excitation winding, a rotary armature with a resonant tuning spring, and an additional mass located in the guide. The mass is connected to the rotary armature's driver via a cylindrical spring, the stiffness of which is determined by expression (1). This allows the drive-chute oscillatory system to be tuned to a resonant frequency. By selecting the spring stiffness c2 for a specific mass m, the system automatically maintains resonant mode, minimizing energy costs for maintaining oscillations and ensuring a stable amplitude even when the material in the chute fluctuates.

[0015] Fig. 1 shows the general view of the device, Fig. 2 shows the cross-section of the tray.

[0016] The device consists of a frame 1, on which a tray 3 for transporting bulk material is installed using elastic elements (springs) 2. On the outer side of the tray 3, a vibration drive 4 is rigidly fixed, which is made in the form of an oscillatory motion electric motor 5, including a stator 6 with an excitation winding, fixedly fixed in the housing of the drive 4, a rotary anchor 7, performing oscillatory movements under the action of the magnetic field of the stator 6, a resonant tuning spring 8, connected at one end to the rotary anchor 7, and the other to the housing of the electric motor 5, an additional mass 9, located in a guide 10, which is rigidly fixed in the housing of the drive 4 and ensures the translational movement of the mass 9, as well as a leash 11, rigidly fixed on the rotary anchor 7 and connected to the additional mass 9 by means of a cylindrical spring 12, wherein the rigidity of the said spring is determined by expression (1).

[0017] A flexible bottom 13 with perforated holes is rigidly fixed to the tray 3. The flexible bottom 13 is kinematically connected through an elastic limiter 14 to an electromagnetic drive 15 fixed to the inner surface of the tray 3 by means of an anchor 16 and elastic limiters 17. The vibration drive 4 and the electromagnetic drive 15 are electrically connected to the control system 18, which in turn is connected to the tray 3 and the flexible bottom 13 through feedback sensors 19 and 20. A gas supply pipe 21 is connected to the tray 3.

[0018] The vibrating conveyor is as follows. The transported bulk material from the hopper (not shown in the figures) is fed to the flexible perforated bottom 13 of the chute 3.

[0019] When voltage is applied to the stator with excitation winding 6, an alternating magnetic field is generated, which sets the rotary armature 7 into oscillatory motion. Resonant tuning spring 8, which connects the armature 7 to the motor housing 5, provides the initial tuning of the oscillatory system. The oscillations of the rotary armature 7 are transmitted via a rigid driver 11 to a cylindrical spring 12. Spring 12, in turn, transmits force to additional mass 9, which begins to reciprocate in guide 10.

[0020] Additional mass 9, located in guide 10 and connected to armature 7 by cylindrical spring 12, together with this spring, forms an inertial dynamic damper for the armature's oscillations. This dynamic damping effect redistributes oscillatory energy from armature 7 to tray 3. As a result, the oscillation amplitude of tray 3 increases, while the oscillation amplitude of armature 7 itself, conversely, tends to zero, enabling dynamic stabilization of armature 7's position in the zone with maximum values ​​of the positional dependence of the driving electromagnetic torque. This ensures maximum efficiency in converting electromagnetic energy into mechanical oscillations.

[0021] Due to the fact that the stiffness of the cylindrical spring 12 is selected based on condition (1), the oscillatory system "rotary anchor 7 - spring 12 - additional mass 9" enters a mechanical resonance mode, which further enhances the dynamic damping effect. This results in the oscillation amplitude of the additional mass 9, and consequently of the entire drive 4, becoming maximal and stable even with minimal energy consumption from the stator 6, while the anchor 7 practically stops in its optimal position. The oscillations from the drive 4 are transmitted directly to the tray 3, causing it to perform directional vibrations with high amplitude and minimal energy consumption.

[0022] At the same time, the control system 18 supplies voltage to the electromagnetic drive 15, fixed on the inner surface of the tray 3. The anchor 16 of the drive 15, through the elastic stops 17 and the elastic stop 14, transmits high-frequency vibrations to the flexible perforated bottom 13. Due to the fact that the bottom 13 is rigidly fixed at the edges on the tray 3, but at the same time is kinematically connected with the independent drive 15, it begins to perform intense bending vibrations (wave-like movements) relative to the tray 3 itself.

[0023] During operation, chute 3, driven by resonantly tuned drive 4, which operates in dynamic damping mode for armature oscillations, performs stable, directional oscillations with increased amplitude, ensuring efficient material transport along chute 3. Simultaneously, flexible bottom 13, driven by drive 15, creates additional waves on its surface. These waves act on the bulk material layer, periodically lifting and "shaking" it, preventing particles from clumping and adhering to the surface of bottom 13.

[0024] Feedback sensors 19 and 20 continuously monitor the vibration parameters of tray 3 and flexible bottom 13, respectively. The signals from sensors 19 and 20 are fed to control system 18, which adjusts the power supplied to drives 4 and 15 in real time. If the process load on tray 3 changes, control system 18 slightly adjusts the supply voltage parameters. However, thanks to the resonant tuning of drive 4 and the dynamic damping effect, the basic vibration amplitude of tray 3 is maintained without a significant increase in energy consumption, and anchor 7 remains within the maximum torque range.

[0025] If it is necessary to simultaneously dry the material, heated air is supplied through the gas supply pipe 21 into the tray of the tray 3, which penetrates the layer of material through the perforation of the flexible bottom 13, actively contacting with the particles brought into suspension by the wave vibrations of the bottom.

[0026] As an example, we will consider a vibrating conveyor for transporting granulated sugar with a capacity of up to 5 t / h, similar to the prototype. We will assume the following parameters of the vibrating system: the mass of the moving parts of the vibrating drive, including the rotary anchor 7 and its associated elements, reduced to the attachment point of the cylindrical spring 12, is m = 2.5 kg; the power supply frequency is 50 Hz, double the frequency is 100 Hz, which corresponds to the angular frequency:

[0027]

[0028] Then the required stiffness of the cylindrical spring 12, according to expression (1), is:

[0029]

[0030] The coefficient of inelastic resistance in the system (damping) is μ≈0.05, and the additional mass 9, which acts as an inertial dynamic damper, is chosen equal to the mass of the moving parts of the drive: m д = 2.5 kg.

[0031] When the dynamic damper is adjusted to the excitation frequency and condition (1) is met, a redistribution of the vibrational energy occurs, as a result of which the vibration amplitude of the armature 7 tends to zero, and the vibration amplitude of the additional mass 9 and the tray 3 connected to it increases.

[0032] In the absence of a dynamic damper (standard oscillatory motion electric motor, as in the prototype), the oscillation amplitude of tray 3, due to the limitation on the angular width of the stator pole and the positional dependence of the driving torque, is x a0 ≈0.01 m.

[0033] When introducing additional mass 9 and coil spring 12 with a calculated stiffness of c2 = 987 kN / m and tuning to resonance, the oscillation amplitude of armature 7 decreases to virtually zero (dynamic stabilization in the zone of maximum electromagnetic torque), and all oscillatory energy is redistributed to additional mass 9. Since additional mass 9 is connected via carrier 11 and drive housing 4 to tray 3, the oscillation amplitude of tray 3 increases. With low damping (μ≈0.05), the oscillation amplitude of tray 3 can increase by 5 times compared to the case of the drive operating without a dynamic damper.

[0034] Thus, due to the fact that additional mass 9 is connected to the armature 7 carrier 11 via cylindrical spring 12, forming an inertial dynamic vibration damper, the vibrational energy is redistributed from the armature to tray 3, which increases the tray's vibration amplitude while simultaneously dynamically stabilizing the armature in the zone of maximum electromagnetic torque. Fulfilling condition (1) places the system in a resonant mode, which, combined with the dynamic damping effect, enables the stated technical result to be achieved—improved energy efficiency and operational stability of the vibrating conveyor by ensuring a resonant vibration mode for the actuator, regardless of the process load.

Claims

A vibrating conveyor comprising a vibrating drive and a control system, a tray mounted on a frame by means of elastic elements, the perforated bottom of which is made flexible and kinematically connected through an elastic limiter with an additional electromagnetic drive secured to the inner surface of the tray, and the control system is electrically connected to the drives by means of feedback sensors, characterized in that the vibrating drive is made in the form of an oscillatory motion electric motor including a stator with an excitation winding, a rotary anchor with a resonant tuning spring and an additional mass located in a guide, connected to the leash of the rotary anchor by means of a cylindrical spring, the rigidity of which is determined by the expression: , where c2 is the stiffness of the cylindrical spring, N / m; m - additional mass, kg; ω is the angular frequency, equal to twice the frequency of the power supply network, rad / s.

Images