TW202421455A - Air-cooled engine casing with oil temperature sensing function capable of eliminating damage to an oil temperature sensor due to temperature rise caused by combustion during engine operation - Google Patents

Abstract

An air-cooled engine casing with an oil temperature sensing function includes a casing body and an oil temperature sensor. The casing body includes a cylinder head part, a cylinder block part, and a crankcase body part located below one side of the cylinder block part and away from the cylinder head part. An engine oil chamber in the crankcase body part is filled with engine oil. The oil temperature sensor is mounted on one side of the lower section of the crankcase body part and is electrically connected to a driving computer system. An oil temperature sensing part of the oil temperature sensor extends into the engine oil chamber and is completely immersed in the engine oil. The oil temperature sensor measures an oil temperature value of the engine oil and transmits the measured oil temperature value to the driving computer system. By arranging the oil temperature sensor away from the cylinder head part, damage to the oil temperature sensor due to temperature rise caused by combustion during engine operation is eliminated.

Description

Air-cooled engine case with oil temperature sensing function

The present invention relates to an engine casing of a motor vehicle, and more particularly to an air-cooled engine casing with an oil temperature sensing function.

The naturally air-cooled engine used in existing fuel-powered motorcycles and other motor vehicles mainly uses the flowing air generated when the motor vehicle is running to cool the engine. The faster the motor vehicle is, the greater the flow rate of the flowing air passing through the surface of the engine, making the cooling effect of the flowing air on the engine better.

In order to protect the engine and prevent the air-cooled engine from being damaged due to overheating, most of the known natural air-cooled engines are equipped with an oil temperature sensor. The oil temperature sensor is used to measure the oil temperature in the engine and transmit the measured oil temperature data to the vehicle's on-board computer system to control the temperature of the engine, so as to protect the engine from overheating and prevent the oil temperature in the engine from rising, which would cause the lubricity of the oil to the engine parts to deteriorate, thus affecting the lubrication of the engine parts.

The aforementioned measurement of the engine oil temperature can not only protect the engine from overheating for EFI type motor vehicles, but also timely correct the amount of oil sprayed by the fuel injection system to the engine according to the oil temperature. Therefore, the measurement signal of the engine oil temperature is a necessary and important measurement signal for existing fuel injection type motor vehicles.

However, in existing air-cooled engines, the oil temperature sensor is usually installed in the engine cylinder head. Since the cylinder head of an air-cooled engine is not easy to dissipate heat, the oil temperature sensor is close to the engine cylinder head, which may cause the oil temperature sensor to measure inaccurate oil temperature. In certain usage situations, it may cause problems such as oil temperature sensor damage. For example: when the vehicle is driving slowly or climbing a hill at a low speed continuously, due to the slow speed, the flow rate of the flowing air passing through the engine surface is slow, and the cooling effect is poor. Under continuous operation of the engine, the temperature of the engine cylinder head is easy to rise, which may cause the oil temperature sensor to be damaged and lose its proper oil temperature sensing function. For EFI-type motor vehicles, in addition to the possibility of engine overheating, the lack of oil temperature measurement data means that the EFI system cannot adjust the amount of oil sprayed to the engine based on the oil temperature.

Furthermore, if a motor vehicle is operated at idle speed for a long time, the lack of flowing air to cool the engine will cause the temperature of the engine cylinder head to rise, which may cause damage to the oil temperature sensor. In order to reduce the temperature of the cylinder head, the cooling blade area of the cylinder head must be enlarged when designing an air-cooled engine. In this way, the volume of the engine cylinder head will increase and take up space, which is not conducive to installing the engine in the body of the motor vehicle. Therefore, based on the volume of the original air-cooled engine, without enlarging the heat sink blades, how to overcome the problem that the oil temperature sensor is easily damaged by inaccurate temperature measurement and overheating due to the slow flow of air passing through the engine surface, which causes the engine to heat up, has become an important issue in the current research and development of air-cooled engines.

The purpose of the present invention is to provide an air-cooled engine casing with an oil temperature sensing function, so as to solve the problems that the cylinder head of the existing air-cooled engine is difficult to dissipate heat, resulting in inaccurate temperature measurement by the oil temperature sensor and easy overheating and damage.

In order to achieve the above-mentioned purpose, the present invention proposes an air-cooled engine casing with an oil temperature sensing function, which can be electrically connected to a vehicle driving computer system, and the air-cooled engine casing includes: A casing body, which includes a cylinder head, a cylinder body located on one side of the cylinder head, and a crankcase portion located below one side of the cylinder body portion away from the cylinder head, the outer surface of the peripheral wall of the crankcase portion has a plurality of heat dissipation fins, and the crankcase portion has an oil chamber, and the oil chamber is filled with oil; and An oil temperature sensor is installed on one side of the lower section of the crankcase and is electrically connected to the on-board computer system. The oil temperature sensor includes an oil temperature sensing portion that can extend into the oil chamber. The oil temperature sensing portion is completely immersed in the oil in the oil chamber and can measure the oil temperature of the oil, and can transmit the measured oil temperature of the oil to the on-board computer system.

With the invention of the aforementioned air-cooled engine case, a temperature sensor is arranged on the lower side of the crankcase portion below the case body. The temperature sensing portion of the temperature sensor directly extends into the oil chamber and is completely immersed in the oil. Thus, the temperature sensor is located far away from the cylinder head portion of the case body, effectively eliminating the situation where the oil temperature sensor is damaged due to the temperature increase caused by combustion during engine operation. At the same time, there is no need to enlarge the heat sink fins of the case to reduce the cylinder head temperature.

Furthermore, if the oil in the oil chamber evaporates or loses, the oil temperature sensing part of the oil temperature sensor will not be completely immersed in the oil but exposed outside the oil, so that the oil temperature sensing part will not be able to accurately measure the oil temperature due to contact with the air, and the vehicle computer system will judge that the oil temperature value is abnormal and light up a warning light.

As shown in Figures 1 and 2, they disclose partial cross-sectional schematic diagrams of a preferred embodiment of the air-cooled engine casing of the present invention. The air-cooled engine casing is used to install a drive mechanism of an engine, and the drive mechanism includes a piston assembly and a crankshaft assembly.

As shown in FIG. 1 and FIG. 2 , the air-cooled engine casing includes a casing body 10 and an oil temperature sensor 20. The casing body 10 includes a cylinder head 10A, a cylinder block 10B, and a crankcase 10C. The cylinder block 10B is disposed on one side of the cylinder head 10A. The cylinder block 10B is used to install the piston assembly. The crankcase 10C is disposed below the cylinder block 10B away from the cylinder head 10A and has an oil chamber 100. The piston assembly can extend into the oil chamber 100. The oil chamber 100 is used to install the crankshaft assembly connected to the piston assembly. The outer surface of the peripheral wall of the crankcase 10C has a plurality of heat dissipation fins.

As shown in Figures 1 and 2, the oil chamber 100 of the casing body 10 is filled with oil 101, and the casing body 10 is equipped with an oil 101 ruler (not shown) that extends into the oil chamber 100 to measure the liquid level of the oil 101. The oil 101 ruler is a known object. The oil 101 ruler has a liquid level marking section that can extend into the oil chamber 100. The liquid level marking section is sequentially set with an oil 101 lower limit and an oil 101 upper limit from bottom to top. The middle position between the oil 101 upper limit and the oil 101 lower limit is defined as an oil 101 middle limit. The liquid level of the oil 101 filled in the oil chamber 100 is higher than the oil 101 lower limit and lower than the oil 101 upper limit.

As shown in Figures 1 and 2, the crankcase portion 10C has an oil chamber bottom plate 12 located at the bottom of the oil chamber 100, and a longitudinal side wall 11 located around the oil chamber 100 and connected to the oil chamber bottom plate 12. The plurality of heat sink fins 13 are arranged on the outer peripheral surface of the oil chamber bottom plate 12 and the outer peripheral surface of the longitudinal side wall 11.

As shown in FIG. 1 and FIG. 2 , the oil temperature sensor 20 is installed on one side of the lower section of the crankcase 10C of the casing body 10 and extends into the oil chamber 100, thereby enabling the air-cooled engine casing of the present invention to have an oil temperature sensing function. The oil temperature sensor 20 can be electrically connected to the vehicle computer system (Engine Control Unit, ECU) of the instrument control mechanism of the motor vehicle. Preferably, the oil temperature sensor 20 is located at the lower section of the crankcase 10C far away from the cylinder head 10A, so as to reduce the influence of the temperature of the cylinder head 10A on the oil temperature sensor 20. The oil temperature sensor 20 includes an oil temperature sensing part 21, which is completely immersed in the engine oil 101 in the oil chamber 100 and can measure the temperature of the engine oil 101, and transmit the oil temperature value of the engine oil 101 to the on-board computer system (Engine Control Unit, ECU) of the instrument control mechanism. The on-board computer system (ECU) is provided with an oil temperature control program and an oil temperature safety value range is set in the database, so that the on-board computer system (ECU) can judge whether the detected oil temperature value of the engine oil 101 is within the oil temperature safety value range based on the oil temperature value of the engine oil 101 detected by the oil temperature sensor 20, and when the oil temperature value of the engine oil 101 exceeds the oil temperature safety value range, the on-board computer system (ECU) can make the instrument control mechanism light up a warning light.

In this preferred embodiment, the oil temperature sensor 20 is sealed and transversely penetrated in the longitudinal side wall 11 of the crankcase portion 10C, and the oil temperature sensing portion 21 extends into the engine oil chamber 100 through the longitudinal side wall 11. Preferably, the height position of the oil temperature sensing portion 21 is higher than the lower limit of the engine oil 101 and lower than the middle limit of the engine oil 101.

By inventing the air-cooled engine case with the oil temperature sensing function, when it is applied to the air-cooled engine of a motor vehicle such as a fuel-powered motorcycle, the flowing air generated when the motor vehicle is running can cool the air-cooled engine case and reduce the temperature of the engine. At the same time, the oil temperature sensor 20 is installed on the crankcase portion 10C of the air-cooled engine casing far away from the cylinder head portion 10A. The oil temperature sensing portion 21 of the oil temperature sensor 20 extends into the engine oil chamber 100 and is completely immersed in the engine oil 101, so that the oil temperature sensor 20 can accurately sense the oil temperature of the engine oil 101. Moreover, by setting the oil temperature sensor 20 at a position far away from the cylinder head portion 10A, the situation in which the oil temperature sensor 20 is damaged due to the temperature increase caused by combustion during engine operation can be effectively eliminated. At the same time, there is no need to enlarge the heat sink fins 13 of the casing to reduce the cylinder temperature.

As shown in FIG3 , if the engine oil 101 in the engine oil chamber 100 evaporates or loses, causing the oil level of the engine oil 101 to be lower than the lower limit of the engine oil 101, the oil temperature sensing portion 21 of the oil temperature sensor 20 is not completely immersed in the engine oil 101 but exposed outside the engine oil 101. At this time, the oil temperature sensing portion 21 will not be able to accurately measure the oil temperature of the engine oil 101 due to contact with the air, causing the vehicle computer system (ECU) to determine that the oil temperature value of the engine oil 101 is abnormal, and the instrument control mechanism will light up a warning light.

Furthermore, the oil temperature sensor 20 can not only accurately sense the oil temperature of the engine oil 101, but also measure the oil temperature value of the engine oil 101 and transmit it to the vehicle computer system (ECU), and the vehicle computer system (ECU) monitors the oil temperature change of the engine oil 101. When the oil temperature value of the engine oil 101 exceeds the oil temperature safety value range, the vehicle computer system (ECU) can light up a warning light to remind the user to deal with it immediately to reduce the damage rate of the engine due to overheating. For an EFI type motor vehicle, the vehicle computer system (ECU) can correct and control the amount of oil sprayed to the engine according to the measured data of the oil temperature of the engine oil 101.

10: Casing body 10A: Cylinder head 10B: Cylinder block 10C: Crankcase 100: Oil chamber 101: Oil 11: Longitudinal side wall 12: Oil chamber bottom plate 13: Heat sink fin 20: Oil temperature sensor 21: Oil temperature sensor

FIG. 1 is a schematic side view of a preferred embodiment of the air-cooled engine casing of the present invention. FIG. 2 is a schematic cross-sectional view of the preferred embodiment of the air-cooled engine casing shown in FIG. 1. FIG. 3 is a schematic view of the state in which the oil temperature sensing portion of the oil temperature sensor is not completely immersed in the oil when the oil level in the oil chamber of the preferred embodiment of the air-cooled engine casing shown in FIG. 1 and FIG. 2 is lower than the lower limit of the oil.

10C: Crankcase

100: Oil chamber

101: Engine oil

11: Longitudinal side wall

12: Oil chamber bottom plate

13: Heat sink fins

20: Oil temperature sensor

21: Oil temperature sensing unit

Claims (3)

An air-cooled engine casing with an oil temperature sensing function, which can be electrically connected to a vehicle driving computer system, the air-cooled engine casing comprising: A casing body, which comprises a cylinder head, a cylinder block located on one side of the cylinder head, and a crankcase located below the cylinder block away from one side of the cylinder head, the outer surface of the peripheral wall of the crankcase has a plurality of heat dissipation fins, the crankcase has an oil chamber, and the oil chamber is filled with oil; and An oil temperature sensor is installed on one side of the lower section of the crankcase and is electrically connected to the on-board computer system. The oil temperature sensor includes an oil temperature sensing portion that can extend into the oil chamber. The oil temperature sensing portion is completely immersed in the oil in the oil chamber and can measure the oil temperature of the oil, and can transmit the measured oil temperature of the oil to the on-board computer system. An air-cooled engine case with an oil temperature sensing function as described in claim 1, wherein the crankcase has an oil chamber bottom plate located at the bottom of the oil chamber and a longitudinal side wall located at the periphery of the oil chamber and connected to the oil chamber bottom plate, the plurality of heat sink fins are arranged on the outer peripheral surface of the oil chamber bottom plate and the outer peripheral surface of the longitudinal side wall, and the oil temperature sensor is sealed and laterally penetrated in the longitudinal side wall. An air-cooled engine case with an oil temperature sensing function as described in claim 1 or 2, wherein the crankcase is provided with an oil dipstick capable of extending into the oil chamber to measure the oil level, the oil dipstick having a liquid level marking section capable of extending into the oil chamber, the liquid level marking section being sequentially provided with an oil lower limit and an oil upper limit from bottom to top, the middle position between the oil upper limit and the oil lower limit being defined as an oil middle limit, the liquid level of the oil filled in the oil chamber being higher than the oil lower limit and lower than the oil upper limit; the height position of the oil temperature sensing portion of the oil temperature sensor being higher than the oil lower limit and lower than the oil middle limit.

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