Hydraulic Heat-Pump Heating for Mobile Working Machine Cabs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Battery-electric industrial trucks face significant energy consumption and reduced range due to direct electrical heating, and existing heat pump solutions are inefficient at low outdoor temperatures, as they rely on ambient air as a heat source.
Innovation Solution
The industrial truck utilizes its hydraulic circuit as a heat source for a heat pump, with a hydraulic circuit heat exchanger to provide a higher temperature source, reducing energy demand from the traction battery, and optionally combines this with an ambient air heat exchanger for enhanced efficiency and comfort.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If direct electrical heating is used in battery-electric industrial trucks, then heating function is achieved, but energy consumption increases significantly and range is reduced
Solution Approach 1:
The invention converts waste heat from the hydraulic circuit, which would otherwise be dissipated, into a useful heat source for heating the driver's cab. The hydraulic fluid operates at elevated temperatures (40-80°C) during normal operation, and this thermal energy is captured via a heat exchanger to preheat air or water that then heats the cab, transforming waste thermal energy into a beneficial heating source and significantly reducing traction battery consumption.
Solution Approach 2:
The invention merges the heating function with the existing hydraulic system by using the hydraulic circuit's thermal energy. Instead of adding a separate heating system that would consume battery power, the solution integrates with the hydraulic system that already operates during truck function, combining waste heat recovery with the heating requirement in a unified system.
2Temperature
If ambient air is used as heat source for heat pump, then heating function is achieved, but efficiency is low at low outdoor temperatures
Solution Approach 1:
The invention changes the temperature parameter of the heat source from ambient air temperature (which can be very low, e.g., -20°C or lower) to hydraulic fluid temperature (which operates at 40-80°C). This parameter change in heat source temperature dramatically improves heat pump efficiency, as the temperature differential between heat source and heat sink is reduced, lowering the work required by the heat pump and reducing energy consumption.
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 solution significantly reduces energy consumption from the traction battery, increasing the range and operating time of the truck by using a higher temperature heat source, while also allowing for efficient heating and cooling of the driver's cab.
Implementation Method 1
a heating heat exchanger (13) which is heated with a heat pump (17), the heat pump (17) using the hydraulic circuit (23) as a heat source via a hydraulic circuit heat exchanger (26)
Implementation Method 2
a heating heat exchanger (13) which is heated with a heat pump (17)
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The device has a heat exchanger (13), where a mobile machine (1) including a hydraulic system, which is utilized as a heat source for heating the heat exchanger. The heat exchanger serves to rise temperature of air of operator's cab (3), and is heated with a heat pump, which uses the hydraulic system as the heat source over a hydraulic circuit heat exchanger. An ambient air heat exchanger (12) is provided as the heat source for the heat pump. Another hydraulic circuit heat exchanger and the ambient air heat exchanger are connected with the heat pump.