Feeder design and production parameters when

  I. Overview
Motor feeder is widely used in electricity, building materials , coal, metallurgy , chemical industry , food industry , used to transport a variety of non-cohesive bulk materials . It is not suitable for handling viscous materials or particle size less than 0.06mm powdery materials.

   Mechanical vibrations screening equipment in many cases be harmful, it affects the machinery and equipment performance and life. On the other hand , also possible to use mechanical vibration . Motor feeder principle is the use of the working parts of mechanical vibration generating periodic motion , which is used to transport materials

.
   Vibrating conveyor Circular vibrating screen many forms , structures differ greatly, the main difference is driven in different ways . Exciter currently used in three ways: the eccentric rod driven ; eccentric inertia -driven and solenoid drivers . Others include the use of hydraulic pneumatic device as a vibrating conveyor drive

Agency, but is seldom used. Benpian is the use of the motor feeder eccentric inertial force driven.
  Second, the operating parameters of the feeder selection
  Feeder operating parameters include the vibration frequency, amplitude , excitation angle , the installation angle. Reasonable choice of operating parameters is important to ensure the normal operation of the machine condition , it is not only to meet the needs of productivity , but also taking into account the machine can withstand dynamic load capacity and consumption

The magnitude of power . Besides transport efficiency is also often closely related with the motion characteristics of the material . So the choice of the operating parameters must also consider the physical properties of the material during transport and dynamic characteristics.
    1 . Mechanical index and throwing index
    Most feeder in the near-resonant conditions of work, materials thrown in a continuous state of motion , generally have high mechanical index . However, considering the level of productivity of the machine , and the conveying distance of the length of the vibrating mass size , to avoid the lack of rigidity and impact material being

Often transported . The mechanical index usually feeder control K = 3 ~ 5, throwing index control Kp = 1.4 ~ 2.5. Transportation brittle materials , the reduction of the material in the course of transmission is too much broken , should adopt a smaller throwing index , or in certain selected under high throwing index

Frequency and smaller amplitude , in order to reduce material and the whereabouts of the tank relative to the impact velocity .
    2 . Excitation angles and mounting angles
    According to the size excitation angle conveyor speed , tank wear and degree of fragmentation of the material requirements and other factors to select , in theory , can depart from the maximum transmission speed of the mechanical index to determine the optimal excitation angle . But in fact many factors affect the transmission speed , the need for full points

Analysis . Motor feeder and generally excitation angle β = 25. ~ 35 . .
    Tank mounting angle is the angle between the horizontal plane ( installation angle ) , the value of the conveying speed of the material influence . Tank mounted down , the feed rate increased significantly. If a = -100 , the conveying speed can be increased about 40% ; α = -15. Can be increased by 75 % or more. However, α values ​​are not

Should be too large, because it not only exacerbate the wear material on the tank , but also by the natural angle of repose of the material limitations . Generally not more than 10. 15 . .
    3 . Frequency and amplitude
    Feeder drive used in different ways, to adapt his range of frequency and amplitude is not the same . To increase the transmission speed , lower frequencies should be used and a larger amplitude. It should be noted that the material falls trough the relative speed and inversely proportional to frequency , so the test

Consider reducing the relative impact velocity material ( for friable material ) should adopt a higher frequency and smaller amplitude.
    The eccentric inertial vibration feeder , due to the eccentric mass and the starting torque limit , the amplitude of 0.5 to 6 , corresponding to a frequency of 12 to 25 Hz , the frequency is too high due to the large dynamic loads often the bearing premature damage.
    4 . Transmission capacity
    Feeder transmission capacity by the width, material thickness , material density and actual average delivery speed decision.
    For different materials, transport of material thickness have different restrictions , such as more than its limit , transmission speed will be greatly reduced. Material thickness and the conveying speed between three cases . Where I is a thin material layer , in this region , the conveying speed with the thickening of the material layer

Rapidly , and soon reached the maximum. Ⅱ area is moderately thick material layer , transmission speed depends mainly on internal friction of the material , and with a slight decrease in the material layer is thicker . Ⅲ area belongs thick layer, in this region , due to breathable material conveying speed decreased significantly reduced .
    Third, the kinetic parameters of the feeder
    Motor feeder axis inertial shakers can generate directional excitation force . Between the two axes of the drive with a gear ratio of l pay connections ensure its rotation in the opposite direction , speed equal. As the two -axis eccentricity of the eccentric mass and the same size , so that the inertial force generated by a

Directions cancel each other , overlap each other in the other direction , the exciting force generated orientation . This force changes periodically , so that a rigid connection with this shaker conveyor trough also be directed periodic vibrations.
    In our study the dynamics of the feeder , the eccentric block is ignored during the rotation unevenness of the vibration parameters of the system , that it is a constant rotational speed . So that you can take it as a mechanical model with a degree of freedom of the system to study . Centrifugal force

Press harmonic changes simplify the calculation process , are close to the actual situation .