Forklift Carriage Bounce Improvement

The goal of the project is.................................

=Problem Definition= The objective of this project is to reduce the bounce in the carriage of a forklift. When a forklift drives over a bumpy surface such as a potholes, cords, hoses, and broken pallets, the carriage of the forklift tends to bounce up and down violently. This bounce is loud, and can cause the operator to spill their load if the bounce is violent enough.

=Background= The "carriage" on a forklift is the part that the forks are held by. The carriage is held up by chains that ride on a pulley on top of the lifting cylinder. The carriage is suspended in air by the lifting chains, and held vertical by the rollers on the carriage that slide up and down inside the channel in the mast. As the forklift drives over a bump, the upwards momentum of the truck will cause the carriage to lift up while the lifting cylinder does not, causing slack in the lifting chains. When the carriage falls back down, it is in free fall until all the slack in the chain is taken and the carriage is stopped abruptly by the tension in the lifting chain. To add to that, the forks are not rigidly attached to the carriage so that the width can be adjusted manually for different loads. When the forks bounce up and down on the carriage, it creates a loud, undesirable clanging sound. Hyster-Yale would like to offer a system on their forklifts as a premium option to reduce the bouncing of the carriage. We will be developing a fully-functional concept prototype that aims to reduce or totally eliminate the bounce in the carriage and the forks.

=Deliverables= We will be developing and building a fully functional prototype that will reduce the carriage bounce on the forklift. The design should be scalable to fork trucks of different lifting capacities.

=Specifications=

User Interface Requirements
There will be little to no user input required in the final design. Ideally, the mechanism will auto-activate whenever there is not an up or down command from the user controls. A disengage function should be incorporated so that the user can disengage the mechanism from the cab of the forklift.

Load Capacity
The mechanism should be able to meet the load capacity of the forklift it will be applied to. Since the goal is a scaleable design, the load capacity should meet or exceed that of the parent forklift.

Surface Types
The carriage damping mechanism should be effective in conditions such as bumpy gravel lots, potholes in asphalt and concrete, and a messy concrete warehouse setting.

=Design Considerations=

Hydraulic Power
If a hydraulically powered solution is pursued, there are a couple of limitations. Hydraulic pressure is limited to 2500psi working pressure. The pressure and flow rate requirement of hydraulics must not limit the abilities of other hydraulic functions on the truck. Ideally, the solution should share hydraulic power and hoses with what currently exists on the mast and carriage of the forklift. There are a limited amount of hoses that can be routed to the carriage. If separate hoses are required for the mechanism, it will limit the number of other attachments that can be implemented on the forklift.

Electrical Power
The forklift runs on a 12 Volt system. Currently, power that is routed to the carriage and mast of the forklift is limited to a headlight circuit. Electrical power faces similar complications with cable routing that hydraulic power faces. Electrical wires routed to the carriage must be able to withstand incredibly high cycle counts before fatigue. Small current draw items such as solenoids can be incorporated, while large current draw items such as motors will require more in-depth project learning.

Safety
Safety is a huge consideration in the design stage. Large factors of safety must be implemented on any component within the load-line of the lift system. All aspects of safely lifting and placing a heavy load must be considered and tested comprehensively.

=Project Learning=

=Final Design=

=Validation=

=Team Members=

=Additional Documentation=

Project Schedule Meeting Minutes

Presentations



Client Interview