Gearbox oil circuit system, crane and gearbox oil circuit system starting method

Abstract

The application belongs to the technical field of power cryogenic cold start engineering and discloses a gearbox oil circuit system, a crane and a gearbox oil circuit system starting method. The gearbox oil circuit system comprises a gearbox body, a gearbox oil circuit, a heating circulating oil circuit and a detection control unit. The heating circulating oil circuit comprises a heating oil tank which is arranged independently of the gearbox body and an electric heater which is arranged in the heating oil tank. The heating oil tank and the gearbox body are communicated through a pipeline. The detection control unit can detect the temperature of the gearbox oil in the gearbox body and control the electric heater and an electric bypass valve. The heating oil tank which is arranged independently of the gearbox body can provide sufficient space to install a larger-power electric heater. The large-power electric heater can ensure that the gearbox oil is rapidly heated to a normal starting temperature under extremely cold conditions, so that the gearbox oil circuit system can also be normally started under extremely cold conditions.

Description

Technical Field

[0001] This invention belongs to the field of power low temperature cold start engineering technology, specifically relating to a transmission oil circuit system, a crane and a method for starting the transmission oil circuit system. Background Technology

[0002] At low temperatures, the quality of the transmission fluid in wheeled cranes changes, leading to difficulty in starting the transmission. Forcing a start not only affects the lubrication of transmission components but also damages internal seals and causes oil leaks, resulting in malfunctions such as weak driving and abnormal shifting. To improve the operating environment of the transmission, a heated transmission exists, which uses an electric heater to heat the transmission fluid. However, due to the small size of the transmission and the numerous internal components, as well as the requirement for the electric heater to be completely submerged in the fluid, the space for installing the heater is limited. This limited space restricts the heater's power, meaning that existing heated transmissions generally have low heating power. When wheeled cranes need to operate in extremely cold regions, these existing heated transmissions are insufficient to meet the requirements. Summary of the Invention

[0003] To address the aforementioned deficiencies or shortcomings, this invention provides a transmission oil circuit system, a crane, and a method for starting the transmission oil circuit system, aiming to solve the technical problem that existing heated transmissions have low heating power and are difficult to adapt to the working environment requirements of extremely cold regions.

[0004] To achieve the above objectives, the present invention provides a transmission fluid system, including a transmission body, a transmission fluid circuit, a heating circulation fluid circuit, and a detection and control unit. The transmission body includes an oil outlet and an oil return port. The transmission fluid circuit includes an oil pump, an electric bypass valve, a cooler, and a lubrication unit connected sequentially from the oil outlet. The electric bypass valve has a bypass branch that bypasses the cooler and connects to the inlet end of the lubrication unit. The outlet end of the lubrication unit is connected to the oil return port. The heating circulation fluid circuit is used to heat the transmission fluid. The heating circulation fluid circuit includes a heating oil tank independently of the transmission body and an electric heater installed in the heating oil tank. The heating oil tank and the transmission body are connected by a pipeline. The detection and control unit can detect the temperature of the transmission fluid in the transmission body and control the electric heater and the electric bypass valve.

[0005] In an embodiment of the present invention, the transmission fluid circuit further includes a filter unit for filtering impurities in the transmission fluid.

[0006] In an embodiment of the present invention, the detection control unit includes a controller and a temperature sensor. The temperature sensor is disposed in the gearbox body, and the controller is connected to the temperature sensor electric heater and the electric bypass valve, respectively.

[0007] In an embodiment of the present invention, the heating oil tank is provided with an installation interface, and the electric heater is installed inside the heating oil tank.

[0008] In an embodiment of the present invention, the heating end of the electric heater is arranged in an elongated shape.

[0009] To achieve the above objectives, the present invention also provides a crane, wherein the crane includes the gearbox hydraulic circuit system as described above.

[0010] In an embodiment of the present invention, the crane includes a frame, a gearbox body, and a heating oil tank mounted on the frame.

[0011] To achieve the above objectives, the present invention also provides a method for starting a transmission fluid system, wherein the method is applicable to the transmission fluid system described above, and the method includes:

[0012] S10: Monitors the temperature of the transmission fluid inside the transmission body;

[0013] S20: When the temperature of the transmission fluid is lower than the preset starting temperature, control the electric heater to heat the transmission fluid until the temperature of the transmission fluid is above the preset starting temperature;

[0014] S30: Start the oil pump, and the transmission oil circuit will start working.

[0015] In an embodiment of the present invention, the transmission oil circuit further includes an electric bypass valve for bypassing the cooler, wherein, after the transmission oil circuit is in operation, it further includes:

[0016] S40: Controls the electric bypass valve to bypass the cooler.

[0017] In an embodiment of the present invention, after controlling the bypass valve to bypass the cooler, the method further includes:

[0018] S50: When the temperature of the transmission oil is higher than the minimum cooling threshold temperature, the electric bypass valve is connected to the cooler, and the electric heater is turned off.

[0019] Through the above technical solution, the transmission oil circuit system provided by the embodiments of the present invention has the following beneficial effects:

[0020] The transmission fluid system provided by this invention includes a heated circulation circuit, which in turn includes a heated oil tank independent of the transmission body and an electric heater installed within the heated oil tank. The heated oil tank, separate from the transmission body and dedicated to heating the transmission fluid, has a large internal space, allowing for the installation of a more powerful electric heater. This high-power heater ensures the transmission fluid is heated to the normal starting temperature even in extremely cold conditions. Furthermore, separating the heated oil tank from the transmission body prevents damage to the electric heater from transmission body vibrations. Additionally, the transmission body, as the confluence of transmission fluid, requires constant protection of its housing strength and sealing. The additional heated oil tank avoids the need for openings in the transmission body and prevents direct heating of the transmission body by the electric heater, thus preventing localized overheating. In summary, the transmission fluid system provided by this invention, by including a heated oil tank independent of the transmission body, provides sufficient space to install a more powerful electric heater. This high-power heater ensures the transmission fluid is heated to the normal starting temperature even in extremely cold conditions, guaranteeing normal start-up of the transmission fluid system under such conditions.

[0021] Other features and advantages of the present invention will be described in detail in the following detailed description. Attached Figure Description

[0022] The accompanying drawings are provided to illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0023] Figure 1 This is a connection diagram of the transmission oil circuit system according to an embodiment of the present invention;

[0024] Figure 2 This is a partial structural schematic diagram of a crane frame equipped with a heating oil tank according to an embodiment of the present invention;

[0025] Figure 3 This is a flowchart of a method for starting a transmission oil circuit system according to an embodiment of the present invention.

[0026] Explanation of reference numerals in the attached figures

[0027] Detailed Implementation

[0028] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0029] The transmission fluid circuit system of the present invention will now be described with reference to the accompanying drawings.

[0030] This invention provides a transmission fluid system, such as... Figure 1 As shown, the transmission fluid system includes:

[0031] The gearbox body 1 includes an oil outlet and an oil return port;

[0032] The transmission oil circuit 2 includes an oil pump 21, an electric bypass valve 24, a cooler 22, and a lubrication unit 23 connected in sequence from the oil outlet. The electric bypass valve 24 is provided with a bypass branch, which bypasses the cooler 22 and is connected to the inlet end of the lubrication unit 23. The outlet end of the lubrication unit 23 is connected to the return oil port.

[0033] The heating circulation oil circuit 3 is used to heat the transmission oil. The heating circulation oil circuit 3 includes a heating oil tank 31, which is independent of the transmission body 1, and an electric heater 32 installed within the heating oil tank 31. The heating oil tank 31 and the transmission body 1 are connected by a pipeline.

[0034] The detection control unit is capable of detecting the temperature of the transmission oil in the transmission body 1 and controlling the electric heater 32 and the electric bypass valve 24.

[0035] The transmission fluid system provided by this invention includes a heated circulation fluid circuit 3, which in turn includes a heated fluid tank 31, which is independent of the transmission body 1, and an electric heater 32 installed within the heated fluid tank 31. The heated fluid tank 31 is independent of the transmission body 1 and dedicated to heating the transmission fluid. The heated fluid tank 31 has a large internal space, allowing for the installation of a higher-powered electric heater 32. This higher-powered electric heater 32 ensures that the transmission fluid is heated to the normal starting temperature even in extremely cold conditions. Furthermore, by separating the heated fluid tank 31 from the transmission body 1, damage to the electric heater 32 from vibrations of the transmission body 1 can be avoided. Moreover, as the confluence of the transmission fluid, the transmission body 1 requires constant assurance of its housing strength and sealing. By providing an additional heated fluid tank 31, openings in the transmission body 1 can be avoided, and direct heating of the transmission body 1 by the electric heater 32 can also prevent localized overheating. In summary, the transmission oil circuit system provided by the present invention provides sufficient space to install a higher-power electric heater 32 by setting a heating oil tank 31 that is independent of the transmission body 1. The high-power electric heater 32 can ensure that the transmission oil is heated to the normal starting temperature under extremely cold conditions, thereby ensuring that the transmission oil circuit system can start normally under extremely cold conditions.

[0036] Specifically, before starting the transmission fluid system, the temperature of the transmission fluid inside the transmission body 1 needs to be checked by the detection control unit. Since the transmission body 1 serves as both the return end and the suction end of the transmission fluid pump, its internal fluid temperature is a better indicator of actual conditions. When the fluid temperature is within the normal range, the transmission fluid system can be started directly. At this time, the oil pump 21 operates to provide power for the transmission fluid flow. The transmission fluid flows out from the outlet, through the cooler 22 and the transmission fluid passage 2, and then back to the return port. Under normal temperature conditions, the transmission fluid temperature rises easily during operation, so it can directly pass through the cooler 22 during startup. When the fluid temperature is low, the transmission fluid needs to be heated first. Since the heating tank 31 and the transmission body 1 are connected by a pipeline, while the electric heater 32 heats the transmission fluid, the fluid in the transmission body 1 and the fluid in the heating tank 31 circulate, thus ensuring uniform heating of the transmission fluid and preventing localized overheating. The power for the circulation of transmission fluid can be provided by a suction pump installed in the transmission body 1 or the heated oil tank 31. Alternatively, the existing oil pump 21 can be used to heat the low-temperature transmission fluid to the starting temperature by heating the oil tank 31 and the electric heater 32, at which point the transmission fluid system can be started normally.

[0037] like Figure 1 As shown, in an embodiment of the present invention, the transmission oil circuit 2 further includes an electric bypass valve 24. The electric bypass valve 24 is disposed between the oil pump 21 and the cooler 22 and is electrically connected to the detection and control unit. The electric bypass valve 24 has a bypass branch that bypasses the cooler 22 and is connected to the inlet end of the lubrication unit 23. When the electric bypass valve 24 is open, the transmission oil flows directly from the bypass branch of the electric bypass valve 24 to the lubrication unit 23. Under extremely cold conditions, once the oil temperature is heated to the preset starting temperature, the transmission oil circuit system can be started normally. However, due to the low ambient temperature, if the transmission oil passes through the cooler 22 in the transmission oil circuit 2, the oil temperature may drop again, resulting in a significant decrease in the lubrication effect of the transmission oil entering the lubrication unit 23. By setting the electric bypass valve 24, the need for the transmission oil to be cooled by the cooler can be controlled according to the actual temperature conditions.

[0038] like Figure 1 As shown, in an embodiment of the present invention, the transmission fluid circuit 2 further includes a filter unit 25, which is used to filter impurities in the transmission fluid. The transmission fluid primarily serves two functions: lubrication and flushing impurities from the transmission components. By providing the filter unit 25, impurities carried away during flushing can be filtered out, increasing the service life of the transmission fluid.

[0039] like Figure 1As shown, in an embodiment of the present invention, the detection and control unit includes a controller and a temperature sensor 4. The temperature sensor 4 is disposed inside the gearbox body 1, and the controller is connected to the temperature sensor 4, the electric heater 32, and the electric bypass valve 24. Specifically, the temperature sensor 4 is disposed on the bottom shell of the gearbox body 1 and is used to directly detect the temperature of the gearbox oil inside the gearbox body 1. The controller and the temperature sensor 4 can be wirelessly connected. A relay can be connected in series in the power supply circuit of the electric heater 32. The relay is also connected in communication with the controller. When the controller receives a signal from the temperature sensor 4, it controls the relay to close the power supply circuit, thereby heating the gearbox oil. At the same time, the controller can control whether the electric bypass valve 24 bypasses the cooler 22.

[0040] like Figure 2 As shown, in an embodiment of the present invention, an installation interface can be provided on the side wall of the heating oil tank 31, and the electric heater 32 is installed inside the heating oil tank 31. When installing the electric heater 32, the heating end needs to be a certain distance away from the tank wall of the heating oil tank 31 to avoid damage caused by local heating of the tank wall. If the installation interface is set on the top wall, the electric heater 32 will be inserted from top to bottom. If the oil level in the heating oil tank 31 is too low, the electric heater 32 will partially leak out of the liquid surface. If the installation interface is set on the bottom wall, it is easy to be affected by oil pressure, which will cause the sealing port to leak oil. Therefore, the electric heater 32 is preferably set on the side wall and the heating end is inserted horizontally into the heating oil tank 31. At the same time, in order to avoid the electric heater 32 leaking out of the liquid surface when the oil level in the heating oil tank 31 is too low, it is preferable to set the electric heater 32 close to the bottom wall.

[0041] like Figure 2 As shown, in an embodiment of the present invention, the heating end of the electric heater 32 is elongated. The elongated shape of the electric heater 32 further increases the contact area with the oil, thereby increasing heat exchange efficiency. Of course, the heating end of the electric heater 32 can also be comb-shaped.

[0042] To achieve the above objectives, the present invention also provides a crane, wherein the crane includes the gearbox hydraulic circuit system described above. Since the crane adopts all the technical solutions of the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated further here.

[0043] like Figure 2As shown, in an embodiment of the present invention, the crane includes a frame 5, a gearbox body 1, and a heating oil tank 31 mounted on the frame 5. Specifically, the crane frame 5 is generally large and has ample space, so a housing mounting base 51 can be welded onto the chassis, the heating oil tank 31 can be mounted on the housing mounting base 51, and then corresponding pipelines can be arranged to connect the heating oil tank 31 and the gearbox body 1, thus completing the setting of the heating circulation oil circuit 3. At the same time, to ensure the liquid level in the heating oil tank 31, the installation height of the electric heater 32 is usually lower than the liquid level in the gearbox body 1.

[0044] like Figure 3 As shown, to achieve the above objectives, the present invention also provides a method for starting a transmission fluid system. This method is applicable to the transmission fluid system described above, and is primarily used for starting the transmission fluid system in extremely low temperature environments. Specifically, the method includes:

[0045] S10: Monitor the temperature of the transmission fluid inside the transmission body 1;

[0046] S20: When the temperature of the transmission fluid is lower than the preset starting temperature, control the electric heater 32 to heat the transmission fluid until the temperature of the transmission fluid is above the preset starting temperature;

[0047] S30: Start oil pump 21, and the transmission oil circuit 2 starts working.

[0048] Before the crane starts, the vehicle's infotainment system performs a self-check, which includes verifying the appropriate temperature of the transmission fluid in the transmission body 1. The threshold for determining appropriate temperature can be set according to the type of transmission fluid. For example, some transmission fluids require a working temperature between 0 and 110°C. When the transmission fluid temperature is far below the working temperature, not only is starting resistance high, but forced starting can also damage the transmission body 1 and other transmission mechanisms. Therefore, in this case, the transmission fluid needs to be heated before starting. The controller operates the electric heater, and the corresponding drive element causes the transmission fluid in the transmission body 1 and the heated oil tank 31 to circulate, thus ensuring uniform heating of the transmission fluid. When the transmission fluid is heated to the preset starting temperature, the oil pump 21 is started, the transmission oil circuit 2 is activated, and then the engine 6 can be started. The entire starting control process can be automatically controlled by the vehicle's infotainment system's built-in program or manually operated. It should be noted that the above-mentioned "until the transmission fluid temperature is above the preset starting temperature" means that the transmission fluid temperature is slightly higher than the preset starting temperature. Due to cost considerations, the detection accuracy of temperature monitoring is low, and the oil is in a flowing state when heated. Therefore, it is difficult to guarantee that the oil temperature will reach a certain value. Heating the transmission fluid temperature to a range slightly higher than the preset starting temperature does not affect the starting of transmission fluid circuit 2.

[0049] In an embodiment of the present invention, the transmission oil circuit 2 further includes an electric bypass valve 24, which is used to bypass the cooler 22. After the transmission oil circuit 2 is operational, it further includes:

[0050] S40: Controls the bypass valve 24 to bypass the cooler 22.

[0051] In cranes operating in extremely low-temperature environments, if the transmission oil is allowed to pass directly through the cooler 22 when the transmission oil circuit 2 is just starting to work, the transmission oil temperature may drop below the normal operating temperature, affecting the lubrication effect of the subsequent lubrication unit 23. Therefore, when the residual heat dissipated by the transmission mechanism is insufficient to maintain the transmission temperature, the cooler 22 needs to be bypassed through the electric bypass valve 24 so that the transmission oil skips the cooler 22 and enters the lubrication unit 23 directly.

[0052] In an embodiment of the present invention, after controlling the bypass valve 24 to bypass the cooler 22, the following is further included:

[0053] S50: When the temperature of the transmission oil is higher than the minimum cooling threshold temperature, control the electric bypass valve 24 to connect the cooler 22 and at the same time turn off the electric heater 32.

[0054] After the transmission mechanism has been operating for a period of time, the residual heat it dissipates will cause the transmission fluid temperature to rise rapidly. When the transmission fluid temperature exceeds the minimum cooling threshold temperature, to prevent the transmission fluid from overheating, the electric heater 32 can be turned off, and the electric bypass valve 24 can be controlled to connect to the cooler 22, so that the transmission fluid temperature is maintained within the optimal operating temperature range. It should be noted that the minimum cooling threshold temperature can be lower than the optimal operating temperature.

[0055] The above starting method enables the transmission fluid system to start normally under extremely low temperature conditions. Only after the transmission fluid system starts can the engine, transmission gears, and other transmission mechanisms start.

[0056] In an embodiment of the present invention, the heating oil tank 31 is connected to the gearbox body 1 and can be directly connected to the oil outlet and oil return port of the gearbox body 1 through a multi-way valve. Therefore, there is no need to open additional connection holes on the housing of the gearbox body 1, thereby ensuring the integrity of the structure of the gearbox body 1.

[0057] In an embodiment of the present invention, the electric heater 32 can be powered by a battery or by a generator.

[0058] In the description of this invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0059] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the connection within two elements or the interaction between two elements, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0060] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0061] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A transmission fluid circuit system, characterized in that, The transmission fluid circuit system includes: The gearbox body (1) includes an oil outlet and an oil return port; The transmission oil circuit (2) includes an oil pump (21), an electric bypass valve (24), a cooler (22), and a lubrication unit (23) connected in sequence from the oil outlet. The electric bypass valve (24) is provided with a bypass branch, which bypasses the cooler (22) and is connected to the inlet end of the lubrication unit (23). The outlet end of the lubrication unit (23) is connected to the return port. A heating circulation oil circuit (3) is used to heat the transmission oil. The heating circulation oil circuit (3) includes a heating oil tank (31) located independently of the transmission body (1) and an electric heater (32) located within the heating oil tank (31). The heating oil tank (31) and the transmission body (1) are connected by a pipeline. The detection control unit is capable of detecting the temperature of the transmission oil in the transmission body (1) and controlling the electric heater (32) and the electric bypass valve (24); Before the oil pump (21) needs to be started, the detection control unit is configured to: if the temperature of the transmission oil in the transmission body (1) is lower than the preset start temperature, control the electric heater (32) to heat, and control the oil in the transmission body (1) to circulate with the oil in the heated oil tank (31).

2. The transmission fluid system according to claim 1, characterized in that, The transmission oil circuit (2) further includes a filter unit (25) for filtering impurities in the transmission oil.

3. The transmission fluid system according to claim 1, characterized in that, The detection and control unit includes a controller and a temperature sensor (4). The temperature sensor (4) is located inside the gearbox body (1). The controller is connected to the temperature sensor (4), the electric heater (32), and the electric bypass valve (24).

4. The transmission fluid system according to any one of claims 1 to 3, characterized in that, The heating oil tank (31) has an installation interface on its side wall, and the electric heater (32) is installed inside the heating oil tank (31).

5. The transmission fluid system according to claim 4, characterized in that, The heating end of the electric heater (32) is elongated.

6. A crane, characterized in that, Includes the transmission fluid system according to any one of claims 1 to 5.

7. The crane according to claim 6, characterized in that, The crane includes a frame (5), the gearbox body (1) and the heating oil tank (31) are mounted on the frame (5).

8. A method for starting a transmission fluid circuit system, characterized in that, The method of starting the transmission fluid system according to any one of claims 1 to 5 includes: Monitor the temperature of the transmission fluid inside the transmission body (1); When the temperature of the transmission fluid is lower than the preset starting temperature, the electric heater (32) is controlled to heat the transmission fluid until the temperature of the transmission fluid is above the preset starting temperature. Start the oil pump (21), and the transmission oil circuit (2) will start working.

9. The method for starting the transmission fluid circuit system according to claim 8, characterized in that, The transmission oil circuit (2) also includes an electric bypass valve (24), which is used to bypass the cooler (22). After the transmission oil circuit (2) is in operation, it further includes: Control the electric bypass valve (24) to bypass the cooler (22).

10. The method for starting the transmission fluid circuit system according to claim 9, characterized in that, After controlling the electric bypass valve (24) to bypass the cooler (22), the following is also included: When the temperature of the transmission oil is higher than the minimum cooling threshold temperature, the electric bypass valve (24) is controlled to connect to the cooler (22), while the electric heater (32) is turned off.

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