Recirculating Elevator Drive Assembly for Hoistway Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional elevator systems are limited in the number of cars that can operate in a hoistway due to the need for load-bearing members and additional components, and as lifting height increases, the weight and size of these members also increase, requiring larger drive machines.
Innovation Solution
The elevator system employs a drive assembly with two or more wheels engaging opposing surfaces of a rail within the hoistway, supported by a bearing assembly, and utilizes a prime mover, such as a wheel hub motor, to apply an engagement force for both support and movement, allowing the elevator car to travel vertically along guide rails and transfer between hoistways without disengagement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If traditional load bearing members (ropes or belts) are used to suspend the elevator car, then the elevator car can be supported and moved along the hoistway, but the number of cars that can operate in the same hoistway is limited and additional components are required
Solution Approach 1:
The patent extracts and eliminates the traditional load bearing members (ropes or belts) and separate drive mechanisms from the system. Instead, the elevator car itself becomes self-propelled through integrated drive wheels that directly engage with the rail, removing the need for external traction components and enabling multiple cars to operate independently in the same hoistway
Solution Approach 2:
The elevator car is designed to be self-propelled with the drive assembly integrated directly into the car structure. The drive wheels, powered by prime movers mounted on the car, provide both support and propulsion functions independently, eliminating the need for external drive machines and load bearing members
2Length of stationary object
If lifting height increases in traditional systems, then the elevator car can reach higher floors, but the weight of the load bearing member increases requiring larger drive machines
Solution Approach 1:
The drive function is segmented and distributed to individual elevator cars rather than being centralized in a single drive machine. Each car has its own prime mover and drive wheels, eliminating the need for a large centralized drive machine and allowing each unit to be sized according to its specific load requirements rather than the total system capacity
Solution Approach 2:
Instead of having the drive machine fixed in the hoistway lift the car (traditional approach), the invention inverts the arrangement by mounting the prime mover on the car itself, which then propels along the rail. This eliminates the need for heavy load bearing members and large drive machines anchored in the hoistway
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration enables efficient operation with multiple elevator cars in a single hoistway, reduces the need for additional components, and maintains vertical orientation during transfers, enhancing operational efficiency and flexibility.
Implementation Method 1
The two or more wheels engage the rail via an engagement force applied by one or more of a spring element
Implementation Method 2
a prime mover is operably connected to a wheel of the two or more wheels to drive rotation of the wheel about a wheel axis
Data Source
AI summary
An elevator system includes a hoistway, a rail extending along the hoistway and an elevator car located in and movable along the hoistway. A drive assembly is operably connected to the elevator car and includes two or more wheels engaged to opposing surfaces of the rail. The drive assembly is configured to apply an engagement force to the rail to both support the elevator car at the rail and drive the elevator car along the rail.