A hybrid cooling liquid heating system
Patent Information
- Application Number
- CN202522419274.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-14
- Publication Date
- 2026-11-03
- Estimated Expiration
- 2035-11-14
AI Technical Summary
Existing diesel engines face difficulties in cold starting in extremely cold regions. Fuel heaters require preheating before starting and have limited power, making it difficult to meet the requirements for rapid starting. At the same time, using fuel heaters increases fuel consumption.
A PTC heater is added to the fuel heater. The positive temperature coefficient thermistor generates heat under the current heating effect and transfers heat through the coolant convection. Combined with the parallel operation of the fuel and electric heaters, dual-fuel heating is achieved.
It enables flexible adjustment of the heating scheme under different environments, achieving fast, clean, and effective engine cold starts, reducing fuel consumption and improving starting reliability.
Smart Images
Figure CN224931778U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a heater, specifically to a coolant heating system that can be used both oil and electricity. Background Technology
[0002] Cold starting of diesel engines in extremely cold regions is one of the problems affecting vehicle use in winter. To solve this problem, most vehicles are equipped with fuel heaters. Diesel fuel from the tank is used as an energy source. After being ignited by the spark plug and burned in the combustion chamber, the released heat is exchanged with the coolant via convection. Once the coolant is heated to a temperature sufficient to support normal engine starting, it is then pumped to the engine. A schematic diagram is shown below. Figure 1 Fuel heaters are of great help in improving engine reliability, reducing starting wear, and increasing the efficiency of the engine and the vehicle as a whole.
[0003] Because the fuel heater requires 5 minutes of electric preheating of the internal spark plugs before starting, and the power of a single fuel heater is limited, it is difficult to meet the requirements for rapid engine starting in winter. Furthermore, using the fuel heater increases overall vehicle fuel consumption. The relationship between fuel heater power and fuel consumption is shown in Table 1. Table 1 Serial number Heater power Heater oil consumption 1 8 kW 1 L / h 2 10 kW 1.3 L / h 3 15 kW 1.8 L / h Utility Model Content
[0004] This invention aims to make the heater no longer solely powered by fuel. It adds a PTC heater to the ordinary fuel heater. The PTC heater is equipped with a positive temperature coefficient thermistor, whose resistance increases stepwise with temperature. When connected to an external 220V power supply, the PTC heater generates heat under the action of current heating effect. The coolant convects with the PTC heater and is then pumped to the engine by the water pump, ultimately achieving the purpose of heating the coolant.
[0005] Meanwhile, this utility model retains the traditional fuel heating system, ultimately achieving three working conditions: separate fuel heating, separate PTC heating, and parallel synchronous operation of fuel heating and PTC heating. Different heating schemes can be flexibly adjusted according to external conditions to achieve flexible matching and adjustment of oil and electric energy, ultimately achieving clean and rapid engine cold start at low temperatures.
[0006] This utility model is achieved through the following technical solution: A dual-use (oil and electricity) coolant heating system includes a fuel heater water circuit and a PTC heater water circuit; The fuel heater water circuit includes: engine outlet 12 - inlet solenoid valve 14 - inlet water distributor 9 (five-way water distributor) - fuel heater 1 - three-way water collector 16 - fuel heater water circuit solenoid valve 18 - three-way water collector 16 - three-way water distributor 17 - water pump 8 - three-way water collector 16 - outlet solenoid valve 19 - engine inlet 20. The fuel heater 1 draws fuel from the fuel tank through the fuel pump 21 and fuel pipe and burns it, and convective heat exchange occurs inside the fuel heater 1. The operation of the fuel heater 1 is controlled by the fuel heater switch 15. The PTC heater water circuit includes: engine outlet 12 - inlet solenoid valve 14 - inlet water distributor 9 (five-way distributor) - PTC heater 2 - three-way water collector 16 - PTC heater water circuit solenoid valve 18 - three-way water collector 16 - three-way water distributor 17 - water pump 8 - three-way water collector 16 - outlet solenoid valve 19 - engine inlet 20. The positive temperature coefficient thermistor inside the PTC heater 2 generates heat under the thermal effect of the current, and the heat is carried away by the coolant through convection heat transfer. The PTC heater 2 is powered by an external 220V power supply 22. The opening and closing of the PTC heater 2 is achieved by the PTC heater switch through the external control box 6, which controls the opening and closing of the solid-state relay 3. The external control box 6 is powered by a 24V power supply 5.
[0007] There are two fuel oil heaters 1, two PTC heaters 2, and two water pumps. The two fuel oil heaters 1 and two PTC heaters 2 are connected to a fuel oil heater water circuit solenoid valve 18 and a PTC electric heater water circuit solenoid valve 18 respectively through a three-way water collector 16. The inlet water distributor 9 is a five-way water distributor, and the four outlet ends are connected to the two fuel oil heaters 1 and the two PTC heaters 2 respectively.
[0008] This invention can freely use diesel or external power as energy, adapting to the efficient cold start of the engine in various environments. Attached Figure Description
[0009] Figure 1 Background Art: Schematic diagram of an existing fuel oil heater; Figure 2 This is a schematic diagram of the present invention. Detailed Implementation
[0010] Example
[0011] The dual-fuel (oil and electric) coolant heating system consists of two fuel heaters (12kW), two PTC heaters (6kW), a heater inlet / outlet manifold, an exhaust pipe, a water pump, water pipes, an external control box, solid-state relay components, a 24V power supply, a fuel heater switch, and a PTC heater switch. The fuel heaters and PTC heaters are bolted to the mounting frame. The outlet and inlet manifolds are bolted to the external skin of the PTC heaters. The water pump is bolted to the PTC heater skin. All water pipe components are connected according to the water circuit diagram using water pipes and clamps.
[0012] The solid-state relay assembly is bolted to the mounting frame, the 24V power supply is bolted to the heater skin, and the external control box is bolted to the heater skin. All the above circuit components are connected using wiring harnesses according to the wiring diagram.
[0013] See the schematic diagram of the water circuit layout of the heating system. Figure 2 .
[0014] When starting the engine at low temperatures using the fuel heater, the fuel heater switch 15 located in the cab is activated. The normally closed inlet solenoid valve 14 and outlet solenoid valve 19 open, as does the fuel heater water circuit solenoid valve 18. Simultaneously, the water pump 8 starts operating, driving the coolant along the following path: engine outlet 12 - inlet solenoid valve 14 - inlet water distributor 9 (five-way distributor) - fuel heater 1 - three-way manifold 16 - fuel heater water circuit solenoid valve 18 - three-way manifold 16 - three-way distributor 17 - water pump 8 - three-way manifold 16 - outlet solenoid valve 1 9- The engine inlet 20 flows, and the fuel heater 1 draws fuel from the fuel tank through the fuel pump 21 and fuel pipe and burns it. Convection heat exchange occurs inside the fuel heater 1, heating the coolant flowing through the fuel heater 1 until the temperature sensor at the heater outlet detects that the water temperature reaches 80°C. At this point, the heater stops working, but the water pump 8 continues to work to ensure that the coolant continues to circulate in the system. When the temperature sensor at the heater outlet detects that the water temperature drops to 65°C, the heater restarts until the water temperature reaches 80°C again and then stops. This cycle repeats continuously.
[0015] With an external 220V power supply, the PTC heater 2 can be used alone for low-temperature starting. When the PTC heater switch 23 located in the cab is activated, the external control box 6 detects the external 220V power supply 22 and confirms that the voltage meets the requirements for the electric heater. It then closes the solid-state relay 3, and the PTC heater 2 enters the working state. Simultaneously, the normally closed heater inlet solenoid valve 14 and outlet solenoid valve 19 open, the PTC electric heater water circuit solenoid valve 18 opens, and the water pump 8 starts working, driving the coolant to flow along the following path: engine outlet 12 - inlet solenoid valve 14 - inlet water distributor 9 (five-way distributor) - PTC heater 2 - three-way water collector 16 - PTC heater water circuit solenoid valve 18 - three-way water collector 16 - three-way water distributor 17 - water pump 8 - three-way water collector 16 - outlet solenoid valve 19 - engine inlet 20. The positive temperature coefficient thermistor inside the PTC heater 2 generates heat under the thermal effect of the current, and this heat is carried away by the coolant through convection heat transfer. When the temperature sensor at the outlet of PTC heater 2 detects that the water temperature has reached 80°C, the external control box 6 disconnects the solid-state relay 3, and PTC heater 2 stops working. However, water pump 8 continues to work to ensure that the coolant continues to circulate in the system. When the temperature sensor at the outlet of PTC heater 2 detects that the water temperature has dropped to 65°C, the external control box 6 closes the solid-state relay 3, and PTC heater starts working until it stops when the water temperature reaches 80°C again. This cycle repeats continuously.
[0016] If the vehicle is in a state that simultaneously meets the operating conditions for both fuel heating and electric heating, the fuel heater switch 15 and PTC heater switch 23 located in the cab can be activated at the same time. Electric heating and fuel heating are connected in parallel and heated synchronously to achieve a maximum peak heating power of 36kW, which meets the needs of the vehicle for rapid low-temperature start-up.
[0017] This utility model has the following features: 1. It can use an external power supply to heat the coolant, thus achieving the purpose of cold starting the engine.
[0018] 2. Diesel fuel can be used alone to heat the coolant, achieving the purpose of cold starting the engine.
[0019] 2. It can simultaneously use both oil and electricity to heat the coolant, meeting the requirements of timely, efficient and clean cold start of the engine in various environments.
Claims
1. A coolant heating system that can be used both oil-fired and electrically, characterized in that: This includes the water circuit for the fuel oil heater and the water circuit for the PTC heater; The fuel heater water circuit includes: engine outlet - inlet solenoid valve - inlet water distributor - fuel heater - water collector - fuel heater water circuit solenoid valve - three-way water collector - three-way water distributor - water pump - three-way water collector - outlet solenoid valve - engine inlet. The fuel heater draws fuel from the fuel tank through the fuel pump and fuel pipe and burns it, with convective heat exchange occurring inside the fuel heater. The fuel heater is turned on by a fuel heater switch. The PTC heater water circuit includes: engine outlet - inlet solenoid valve - inlet water distributor - PTC heater - water collector - PTC heater water circuit solenoid valve - three-way water collector - three-way water distributor - water pump - three-way water collector - outlet solenoid valve - engine inlet. The positive temperature coefficient thermistor inside the PTC heater generates heat under the thermal effect of current, and the heat is carried away by the coolant through convection heat transfer. The PTC heater is powered by an external 220V power supply. The PTC heater is turned on and off by the PTC heater switch through an external control box that controls the solid-state relay. The external control box is powered by a 24V power supply.
2. The dual-use (oil and electricity) coolant heating system according to claim 1, characterized in that: There are two fuel oil heaters, two PTC heaters, and two water pumps. The two fuel oil heaters and the two PTC heaters are connected to a fuel oil heater water circuit solenoid valve and a PTC electric heater water circuit solenoid valve respectively through a three-way water collector. The water inlet is a five-way water distributor, and the four water outlets are connected to the two fuel oil heaters and the two PTC heaters respectively.