Vibration Technology: Making the right choices

Vibration Technology: Making the right choices
AViTEQ has 82 years of experience in the design and supply of Vibration Handling equipment.

The company is proud of its wealth of experience in its workforce. This experience means that AViTEQ can provide technical solutions to each customer’s given application.

AViTEQ has the rare ability to draw upon its own range of vibrator drive units, these include Magnetic Vibrators, Unbalance Vibrator Motors, and Compact (Linear) Feeder Vibrators. This is something that not all suppliers of Vibration Handling equipment can note.

The success in all application solutions starts with the correct selection of the vibrator units themselves. The key is to fully understand the differences between the various options available.

Vibration Technology: Making the right choices

Magnetic Vibrators

Magnetic Vibrators are twin-mass vibrating systems, they contain an electrical coil and armature. The armature is fastened to a steel mass called the free mass, this mass is supported by a nest of leaf springs. The free mass must be set to a specific weight so to ensure the natural frequency is within a specific value.

Once tuned Magnetic Vibrators can be infinitely adjusted so to control the material flow rate, this is possible by utilizing a thyristor controller. Magnetic vibrators are available in 25Hz, 33Hz & 50Hz (50Hz Supply Frequency) working frequencies. They have the ability to start and stop instantly, therefore minimizing the amount of in-flight material falling from the feeder tray. These two abilities mean they are generally utilized for dosing and weighing applications, where fine feed rate control is required and instantaneous stopping is needed.

Where required due to the overall size and weight of the feeder/screen, multiple Magnetic Vibrators can be utilized, all synchronized via the controller unit.

For peace of mind, AViTEQ also supplies a range of Magnetic Vibrators, which have a closed-loop feedback system named “PAL”. Vibrators utilizing PAL self-regulate the vibrator voltage based on the actual amplitude of the vibrator. This, therefore, prevents premature vibrator failure, which can occur if the Magnetic Vibrator becomes out of tune or due to other fault conditions. This, therefore, reduces the overall cost of ownership to the customer.

Unbalance Vibrator Motors

Unbalanced Vibrator Motors are typically installed in pairs for conveying applications or singularly for circular motion screens. Unbalance Vibrator motors are assembled using a 2, 4, 6, or 8 pole Asynchronous Motor with output shafts at either end. Centrifugal weights are fitted to each output shaft and are adjustable to allow for the adjustment of the working stroke and subsequently allows for adjustment of the material flow rate.

By utilizing two unbalance vibrator motors both contra-rotating this will produce a synchronized linear vibration. When wired directly there is no adjustment possible without stopping the motors and adjusting the centrifugal weights. When installed with a frequency controller (inverter) variance in the material flow rate can be achieved by adjusting the speed of the motors.

Due to the nature of unbalance motors rotating at high speed, when stopping the motors the machine will pass through resonance and therefore have increased motion, which will cause the material to continue to fall from the tray until completely stopped. By using a braking unit the stopping time can be reduced to 2-3 seconds. Due to this, unbalance vibrator motors are generally utilized for vibrating feeder and screens where they do not need to stop very often and minimal material flow control is required.

Compact (Linear) Feeder Vibrators

Compact Feeder vibrators operate in a very similar way to the magnetic vibrator, both are twin-mass vibrating systems. Therefore tuning of the units is critical for safe and effective operation.

Compact Feeder vibrators by their design can be directly mounted to a support frame or floor, the feeder trough or screen trough can be directly mounted to the drive unit thereby creating a simple yet very effective application solution. These vibrator units are available in several working frequencies 25Hz, 50Hz & 100Hz (50Hz Supply Frequency). Depending on the material to be handled will affect which frequency to be selected.

This article is published by

AViTEQ Vibrationstechnik, the former AEG Vibrationstechnik - Frankfurt/Main, offers its clients technological sophisticated and reliable solutions for different branches of industry in vibration-, feeding- and handling technology.

AViTEQ Vibrationstechnik - Solutions in solids handling and processing

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