Eiffel Tower - Tourism - Passenger Lifts - Ground To The Second Level

Ground To The Second Level

The original lifts (elevators) to the first and second floors were provided by two companies. Both companies had to overcome many technical obstacles as neither company (or indeed any company) had experience with installing lifts climbing to such heights with large loads. The slanting tracks with changing angles further complicated the problems. The East and West lifts were supplied by the French company Roux Combaluzier Lepape, using hydraulically powered chains and rollers. The North and South lifts were provided by the American company Otis using car designs similar to the original installation but using an improved hydraulic and cable scheme. The French lifts had a very poor performance and were replaced with the current installations in 1897 (West Pillar) and 1899 (East Pillar) by Fives-Lille using an improved hydraulic and rope scheme. Both of the original installations operated broadly on the principle of the Fives-Lille lifts.

The Fives-Lille lifts from ground level to the first and second levels are operated by cables and pulleys driven by massive water-powered pistons. The hydraulic scheme was somewhat unusual for the time in that it included three large counterweights of 200 tonnes each sitting on top of hydraulic rams which doubled up as accumulators for the water. As the lifts ascend the inclined arc of the pillars, the angle of ascent changes. The two lift cabs are kept more or less level and indeed are level at the landings. The cab floors do take on a slight angle at times between landings.

The principle behind the lifts is similar to the operation of a block and tackle but in reverse. Two large hydraulic rams (over 1 metre diameter) with a 16 metre travel are mounted horizontally in the base of the pillar which pushes a carriage (the French word for it translates as chariot and this term will be used henceforth to distinguish it from the lift carriage) with 16 large triple sheaves mounted on it. There are 14 similar sheaves mounted statically. Six wire ropes are rove back and forth between the sheaves such that each rope passes between the 2 sets of sheaves 7 times. The ropes then leave the final sheaves on the chariot and pass up through a series of guiding sheaves to above the second floor and then through a pair of triple sheaves back down to the lift carriage again passing guiding sheaves.

This arrangement means that the lift carriage, complete with its cars and passengers, travels 8 times the distance that the rams move the chariot, the 128 metres from the ground to the second floor. The force exerted by the rams also has to be 8 times the total weight of the lift carriage, cars and passengers, plus extra to account for various losses such as friction. The hydraulic fluid was water, normally stored in three accumulators, complete with counterbalance weights. To make the lift ascend, water was pumped using an electrically driven pump from the accumulators to the two rams. Since the counterbalance weights provided much of the pressure required, the pump only had to provide the extra effort. For the descent, it was only necessary to allow the water to flow back to the accumulators using a control valve. The lifts were operated by an operator perched precariously underneath the lift cars. His position (with a dummy operator) can still be seen on the lifts today.

The Fives-Lille lifts were completely upgraded in 1986 to meet modern safety requirements and to make the lifts easier to operate. A new computer-controlled system was installed which completely automated the operation. One of the three counterbalances was taken out of use, and the cars were replaced with a more modern and lighter structure. Most importantly, the main driving force was removed from the original water pump such that the water hydraulic system provided only a counterbalancing function. The main driving force was transferred to a 320 kW electrically driven oil hydraulic pump which drives a pair of hydraulic motors on the chariot itself, thus providing the motive power. The new lift cars complete with their carriage and a full 92 passenger load weigh 22 tonnes.

Owing to elasticity in the ropes and the time taken to get the cars level with the landings, each lift in normal service takes an average of 8 minutes and 50 seconds to do the round trip, spending an average of 1 minute and 15 seconds at each floor. The average journey time between floors is just 1 minute.

The original Otis lifts in the North and South pillars in their turn proved to be inferior to the new (in 1899) French lifts and were scrapped from the South pillar in 1900 and from the North pillar in 1913 after failed attempts to repower them with an electric motor. The North and South pillars were to remain without lifts until 1965 when increasing visitor numbers persuaded the operators to install a relatively standard and modern cable hoisted system in the north pillar using a cable-hauled counterbalance weight, but hoisted by a block and tackle system to reduce its travel to one third of the lift travel. The counterbalance is clearly visible within the structure of the North pillar. This latter lift was upgraded in 1995 with new cars and computer controls.

The South pillar acquired a completely new fairly standard electrically driven lift in 1983 to serve the Jules Verne restaurant. This was also supplied by Otis. A further four-ton service lift was added to the South pillar in 1989 by Otis to relieve the main lifts when moving relatively small loads or even just maintenance personnel.

The East and West hydraulic (water) lift works are on display and, at least in theory, are open to the public in a small museum located in base of the East and West tower, which is somewhat hidden from public view. Because the massive mechanism requires frequent lubrication and attention, public access is often restricted. However, when open, the wait times are much less than the other, more popular, attractions. The rope mechanism of the North tower is visible to visitors as they exit from the lift.

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