Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65G—TRANSPORT OR STORAGE DEVICES, e.g. CONVEYORS FOR LOADING OR TIPPING, SHOP CONVEYOR SYSTEMS OR PNEUMATIC TUBE CONVEYORS
  • B65G27/00—Jigging conveyors
  • B65G27/10—Applications of devices for generating or transmitting jigging movements
  • B65G27/32—Applications of devices for generating or transmitting jigging movements with means for controlling direction, frequency or amplitude of vibration or shaking movement

Definitions

• the invention relates to a device for controlling of magne ⁇ tically driven mass oscillating systems, such as conveyours or the like, in which the resonance frequencies are diffe ⁇ rent and moreover can vary in any way during operation.
• So-called magnetic oscillating conveyors are very often used in industry for moving of bulk materials or small pie ⁇ ces. These devices consist of a conveyor part, which is designed as a conveyor trough, conveyor pipe or conveyor chute, in addition to a countermass (stator). The conveyor part and the countermass are connected with one another by spring elements. These devices are designated in the litera ⁇ ture by the full name of so-called magnetically driven 2-mass oscillating systems.
• the spring elements in each case are mounted at an angle opposite a stationary base, i.e., opposite the contermass, and the 2-mass system oscillates with the aid of an electro ⁇ magnet, i.e., a magnet armature and magnet coil, then the pieces on the conveyor chute that are to be conveyed begin to move in a fixed direction, corresponding to a so-called projectile motion.
• an electro ⁇ magnet i.e., a magnet armature and magnet coil
• the natural frequency of a 2-mass oscillating system is calculated from
• Useful weight table weight + conveyor attachment + the weight of the partly coupled material to be conveyed. (formula 3)
• the object of the invention is to eliminate said disadvanta- ges with a conveyor of the type initially mentioned, so that as a rule resonance adjustment of the mass oscillating system can be dispensed with from now on, since this invention ad ⁇ justs to the resonance with its excitation frequency.
• the excitation frequency can be adjusted to the respective resonance frequency and consequen ⁇ tly all problems relating to changes of masses, changes of spring constants, etc. can be avoided.
• the necessary excita ⁇ tion energy in this case is only a fraction of the previously necessary excitation energy, since now only the damping of themechanical resonant circuit must be overcome.
• the oscilla ⁇ tion amplitude also can be controlled in a simple way with the same measuring device by controlling the excitation energy.
• Figure 3 shows the design of an embodiment of the oscilla ⁇ ting conveyor according to the invention
• Figure 4 diagrammatically shows the design of the electric control and power circuit.
• a conventional magnet oscillating conveyor is shown in figure 1.
• 1 indicates the conveyor chute
• the table and con ⁇ veyor chute together form the useful mass or useful weight.
• the magnet armature is indicated by 4 and the magnet coil by 5, while the countermass or stator is indicated by 6.
• the device rests on decoupling spring elements, especially on rubber feet 7.
• Spring elements 6 form, with the base of coun ⁇ termass 6 a spring angle of incidence 8, or ° ⁇ , while 9 indicates the projectile path of a small piece.
• Figure 2 shows the relation between the oscillation ampli ⁇ tude and the ration of the driving frequency to the resonance frequency in the case of different dampings.
• the letter R indicates the resonance shift as a result of a damping change and D + G the damping and resonance influence by loading of the chute;
• Adjustment of the natural frequency is obtained by changing of the spring constants or changing of the weights, above all the useful weight.
• Figure 3 corresponds to the fundamental design of a oscilla- tion conveyor of conventional construction (according to fig. l), which according to the invention was supplemented with a phase and amplitude measuring system.
• the measuring system consists of a measuring coil 11 and a permanent magnet 10. If the trough oscillates perfectly, the voltage produced in the measuring coil is sinusoidal.
• the crossover of the measuring voltage coincides with the maximum deviation of the trough.
• - Power bridge circuit 16 if both transistors Tl and T2 be ⁇ come simultaneously conducting, the voltage from Cl is applied to the excitation coil of the oscillating conveyor, a current beings to flow. If the transistors are again opened and thus further rise of the coil current is interrupted, the polari ⁇ ty on the excitation coil immediately changes. Thus, diodes D1-D2 become conducting and recharge the decreasing coil cur ⁇ rent in energy storage Cl; - Permanent magnet 17 fastened to the conveyor trough;
• phase discriminator 19 the transient excitation frequen- cy and the measuring frequency are fed to it. A positive or negative voltage is formed on its output, depending on whe ⁇ ther the excitation frequency is greater or smaller than the resonance frequency of the oscillating conveyor;
• phase integral controller 20 it changes its output volta- ge in the correct action direction until the phase discrimi ⁇ nator no longer supplies any correction voltage;
• - Measuring rectifier 23 from the measuring ac voltage it makes a dc voltage that is proportional to the amplitude of the conveyor troughj
• - Amplitude controller 23 it compares the set voltage on the set-point adjuster with that from the measuring rectifi ⁇ er and with its output voltage drives the pulse-duration modulator;
• Pulse-duration modulator 24 it receives the correct fre ⁇ quency and phase position from the voltage-controlled oscil ⁇ lator and the information on the necessary excitation energy from the amplitude controller and makes therefrom a through- connected pulse at the correct moment and in the correct length fro transistors Tl and T2.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Jigging Conveyors (AREA)
• Apparatuses For Generation Of Mechanical Vibrations (AREA)
• Particle Accelerators (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=4283235

Family Applications (1)

Country Status (4)

Families Citing this family (22)

Family Cites Families (2)

• 1984
  • 1984-10-05 CH CH482784A patent/CH666359A5/de not_active IP Right Cessation
• 1985
  • 1985-09-17 EP EP19850905322 patent/EP0197136A1/de not_active Withdrawn
  • 1985-09-17 AU AU48682/85A patent/AU4868285A/en not_active Abandoned
  • 1985-09-17 WO PCT/EP1985/000479 patent/WO1986002058A1/en not_active Ceased

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events