Elevators Rise to the Occasion

Elevators Rise to the Occasion

In the absence of elevators imagine how one dimensional our surroundings would be. Sky scrapers would be unheard of. Luxury penthouses and office buildings high above ground level would seem futuristic. In today’s world it’s rare to find an establishment without an elevator. Citywide Elevator Consultants concentrate on a full range of services for all types of vertical transportation including new construction and modernization of major hotels, universities, government facilities, commercial and residential buildings and retail locations. Relying solely on stairs to get from point A to point B is impractical. The elderly or people with a handicap, such as a wheel chair, are unable to climb flights of stairs in order to reach their destination. In the 1990’s the introduction of the Federal Americans with Disabilities Act required buildings over two or three stories to be retrofitted with elevators. 

Elevators have existed for many centuries. In the 1600’s manually operated elevators were used for lifting freight in manufacturing plants and warehouses. Elisha Otis’ invented what we now recognize today as a modern elevator. Otis incorporated a safety brake system to the elevator. With this new feature elevator safety became a priority.  Elevators were first operated by steam power that would turn cable drums. It was in 1871 that hydraulic elevators made their debut.  Hydraulic elevators used water pressure as their power source. Almost twenty years later the first electric elevator was installed. There were many advantages to the electric elevator. Firstly, electric power was becoming more available to the masses. Secondly, unlike hydraulic elevators, electric elevators have no height limit. 

Elevator technology continued to progress. In early years, human operators were required in order to control the speed, stopping, and opening and closing of elevator doors. In the 1950’s, with the advancement of automatic pushbutton control systems, operators were not longer required. In the 70’s solid state electronic controls replaced electromechanical controls. With the increasing popularity and necessity of the elevator, safety became a top precedence. Within an elevator there are two key safety mechanisms: a governor and electromechanical door interlocks. A governor controls the speed of the elevator. The electromechanical door interlocks prevent the elevators from operating if the doors are not completely closed. This door interlock also prevents outer floor doors from opening if the elevator is not present. 

While the basic concept and design of the elevator has not changed much over the past fifty years, the control systems have advanced greatly. The control systems have changed to improve safety and speed of operation. Counterweights ensure that an elevator cannot fall while the cable is intact. In a traction drum installation, the cable runs from the elevator, up and once around a drive drum attached to the hoist motor, then back to the counterweight. The elevator car and the counterweight each run in their own sets of guide rails. A secondary governor cable runs from the car up to a governor pulley, then down to a tension pulley at the bottom of the elevator shaft, and up to the car again. This cable rotates the governor pulley at a speed directly proportional to the speed of the car. The governor uses another cable to activate the emergency brake jaw that grips the guide rails in the occurrence of extreme car speed. This aids in slowing the car to a stop. 

For stability and strength elevator cars are built with steel framework. Steel beams are located above the car that holds the pulley for the hoist cable. These beams are known as the crosshead. A sling, which is a steel structure, extends down the sides of the car. The sides of the car are made from steel sheet and are trimmed on the inside with decorative paneling. Inside the car the floor is tiled or carpeted. Other interior trim is finished with stainless steel. 

Elevators have left an enormous mark on our society. They have helped to shape and grow cities all over the world. In the 1800’s with urban growth on the rise, elevators aided in providing people with apartment living. With the invention of the elevator people were able to live in apartments many stories off the ground. With advancing technology, the elevator industry is always evolving. Citywide Elevator Consultants offers world class elevator and escalator solutions unrivaled in the industry. The Citywide team optimizes elevator maintenance standards for national clients with elevator portfolios that extend across the United States and beyond. Citywide incorporates engineering expertise, technical training, field experience, and a customer-centric approach to help clients maximize the value of their buildings. CEC understands the significant role elevators play in our society.