Zero-Turn Mower Blade Control Through Unified Motor Coordination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ZTR mowers with electric powertrains face challenges in synchronizing the rotational speed and direction of multiple electric motors for the wheels and blades, requiring complex control systems that lack coordinated operation.
Innovation Solution
A single master controller is used to manage the rotational speed and direction of both the electric wheel motors and blade motors, coordinating their operation through a series of control lines and position sensors, allowing for precise synchronization and enhanced maneuverability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If multiple separate controllers are used for each electric motor in the electric powertrain, then each motor can be controlled independently, but the control system becomes complex and coordination between motors becomes difficult
Solution Approach 1:
The patent consolidates multiple separate motor controllers into a single integrated controller that manages all electric motors in the powertrain (wheel motors, blade motors, etc.). This unified controller receives operator inputs and distributes appropriate control signals to each motor, reducing the number of separate control units while maintaining independent control capability for each motor function.
Solution Approach 2:
The integrated controller is designed to perform multiple functions simultaneously - it controls wheel motors for propulsion and steering, blade motors for cutting operations, and coordinates their operation based on the same operator inputs. This multi-functional approach eliminates the need for separate dedicated controllers for each motor type.
2Device complexity
If a single master controller coordinates all electric motors, then motor synchronization is improved and system complexity is reduced, but the requirement for precise control signaling increases
Solution Approach 1:
The integrated controller incorporates feedback mechanisms that monitor the actual performance of each electric motor and adjust control signals accordingly. This feedback loop ensures precise coordination by continuously comparing desired motor responses with actual responses and making real-time corrections to maintain synchronization and proper operational coordination.
3Object-affected harmful factors
If electric storage batteries replace the internal combustion engine, then emissions are reduced and operational quietness is improved, but the power delivery characteristics and motor synchronization requirements change
Solution Approach 1:
The patent replaces the mechanical internal combustion engine system with an electric powertrain system using storage batteries and electric motors. This substitution eliminates emissions and noise while requiring a different control approach - using electronic control signals rather than mechanical power transmission coordination. The integrated controller manages the electric motors to replicate the functional capabilities of the engine system.
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
The single master controller enhances the operational efficiency and battery life of the ZTR mower by optimizing motor speeds based on wheel speed, reducing power consumption, and adapting to turning maneuvers, thereby improving the overall performance and usability.
Implementation Method 1
The master controller is configured to send voltage pulses to the multiple blade motors
Data Source
AI summary
A zero turn radius (ZTR) mower includes a pair of rear drive wheels, a mowing deck including a plurality of cutting blades, an electric storage battery, a pair of electric wheel motors each configured to rotate one of the rear drive wheels, a plurality of electric blade motors each configured to rotate one of the plurality of cutting blades, and a master controller configured to control a rotational speed of each of the pair of wheel motors and each of the plurality of blade motors, the master controller configured send voltage pulses to the plurality of blade motors and to adjust the rotational speeds of the plurality of blade motors separately such that the cutting blades selectively rotate at different rotational speeds.