Vertical Baggage Transport

Airport baggage handling systems are usually not limited to one level only. Baggage has to be transported up or down between several levels and several functional areas. Traditional solutions involve inclining conveyors and spiral lifts. Very often space constraints are a major challenge these days, as systems are often extended with additional x-ray machines, etc.

Analysing a typical airport situation, baggage often needs to be conveyed from check-in, down to the sorting level. A decline conveyor with an angle of 15" would need a conveyor length of 23m for a height difference of 6m. At a speed of 1m/s a suitcase would take 23 seconds to reach the sorting level. The conveyor would occupy approximately 28m of valuable space. If the sorting level is even further down the time will multiply and even more space will be required.

For out of gauge (OOG) baggage, typically 2m long and 1m wide, a spiral lift would need an inside diameter of 1.2m, a conveying width of 1.3m and an outside diameter of 5m. With some space for supports, a spiral lift would occupy about 30m(sq) including supports, etc. The centreline of this spiral lift would have a length of 25m with a centre line angle of 17" and a 720" rotation. A suitcase would take 25 seconds to travel at a speed of 1m/s.

VERTICAL CONVEYOR A comparatively new, but already well-proven technology is the continuous vertical conveyor (CVC). For the same size OOG baggage this conveyor will occupy only 7m(sq) (3.5 x 2). Baggage is transported on horizontal segmented platforms. These platforms are attached to continuous running rubber block chains, giving the system the impression of an almost uninterrupted flow. The platforrns on the flexible rubber block chain turn around the end idler wheel at the entry end and baggage is fed onto the platforms from the infeed conveyor.

When all the platform segments have come up, the platform starts its vertical movement. Baggage is brought to the discharge level, where the platforms move around the end idler wheel, delivering the baggage to the takeaway conveyor and into the system. The platform moves upwards again at the rear of the lift, reaches the entry station and is ready to pick up the next piece of baggage. At a speed of 0.6m/s, a suitcase takes 12 seconds from entry to exit, less than 50 percent of the time reguired by other solutions.

Benefits of the this systems include:
• Rubber block chains do not need greasing.
• The rubber absorbs the majority of the operational noise and vibrations, giving the CVC a very quiet and smooth operation.
• Inside the rubber blocks are pre-stressed steel cables. These cables hold the bad and take the forces. Pre-stressing prevents the rubber block chain from stretching, so frequent chain tensioning is not necessary.
• The system is very maintenance friendly. Visual inspection and cleaning of the light sensor reflectors is the main work.
• The CVC does not involve conveyor belts, so storage of expensive spare parts and frequent replacement of worn belts is not necessary. The total cost of ownership is reduced considerably.

The CVC is designed for high-capacity transportation of loose luggage, trays and even pallets up to 2,000kg, between two levels. lt can be built with heights up to 50m. Internal cladding closes the travelling path almost completely, ensuring flawless transfer of conveyed luggage. lt prevents catching of loose luggage items such as handles and cords, and guarantees that no luggage is lost during transport.

The conveyor is very energy efficient with a single small motor, giving low power consumption and operational costs. Connection to the power supply is fast and easy. The CVC has only a few light sensors that are usually controlled by the system PLC, so a separate PLC is not necessary.