Hydraulic Elevator
Hydraulic elevators are heavy-duty elevators built for frequent, long-term use. They also have an ultra-smooth ride quality and are typically very quiet. They are one of the best elevators for durability, larger weight capacities, and serving a higher number of floors.
The system operates with a hydraulic pump connected to a cylinder that will raise and lower a piston to move the elevator cab. The elevator will lift under pressure of the hydraulic fluid pumped into the cylinder when a call button is pressed from a higher floor.
To travel in the down direction, the controller will open a valve in the hydraulic tank slowly releasing this pressure after a lower floor call has been placed. Since this type of elevator can travel down by simply opening a control valve and pull from gravity it is also what makes them efficient in the use of power. They can even be lowered by battery backup in the event of a power failure with automatic operation.
Hydraulic Elevator Safety Features
Hydraulic Elevators are some of the safest in the industry. The systems have several features built-in for fail-safe operation. One of the best features of hydraulic systems is the elevators are engineered and designed specifically for each individual installation. Because of this, they will only travel to the maximum total floor-to-floor distance plus 2″-3″ of runby or overtravel (extra buffer space), meaning they can never move more than a few inches past the top landing.
The elevators will also include a flow control switch to prevent overspeed in the down direction and a pump-run timer to monitor the travel time between landings. The rated speed for an in-home hydraulic elevator is 40 fpm, traveling 20 feet will take approximately 30 seconds. The cabs are supported with two 3/8" diameter steel cables rated for thousands of pounds. The cables are connected to an instantaneous braking system that is also continuously monitored by a PLC-based controller.