CN108007525A - A kind of level monitoring device and vehicle fuel level monitor system - Google Patents

Abstract

The embodiment of the invention discloses a liquid level monitoring device and a vehicle oil level monitoring system, which are used to measure the liquid level of the liquid in the liquid storage device. The liquid level monitoring device includes a liquid level monitoring module and a control module; the liquid level monitoring module is set In the liquid storage device and electrically connected to the control module, the liquid level monitoring module includes a housing, a float arranged inside the housing, and a liquid level sensing block arranged on the float, and a liquid inlet is provided at the bottom of the housing , used to balance the liquid level in the housing and the liquid storage device, the float is used to float on the liquid surface, the liquid level sensing block is electrically connected to the control module and used to detect liquid level information and provide liquid level information to the control module; the control module Set outside the liquid storage device for receiving liquid level information. The liquid level monitoring device provided by the embodiment of the present invention can accurately monitor the liquid level of the liquid in the liquid storage device.

Description

A liquid level monitoring device and a vehicle oil level monitoring system

technical field

The embodiments of the present invention relate to liquid level detection technology, in particular to a liquid level monitoring device and a vehicle oil level monitoring system.

Background technique

Existing liquid level detection technologies include ultrasonic, liquid pressure and gas pressure measurement methods. The ultrasonic measurement method is mainly to calculate the distance according to the return time when encountering the medium through the sound wave transmission. The liquid pressure measurement method is to measure the liquid level depth by means of the pressure principle. The gas pressure measurement method is to use the principle that the gas can be compressed by the liquid to test the air pressure. Calculate the liquid level height.

Ultrasonic liquid level measuring devices are bulky and have requirements for measuring distance accuracy. Generally, it is difficult to measure distances within 20cm, so they are suitable for deeper containers. The liquid pressure liquid level measuring device can hardly measure the liquid level change in the 18cm deep oil tank, and the cost is high. Gas pressure and liquid level measuring devices have large measurement errors and high costs due to changes in air compression rate with ambient temperature.

Contents of the invention

Embodiments of the present invention provide a liquid level monitoring device and a vehicle oil level monitoring system for accurately monitoring the liquid level of a liquid in a liquid storage device at low cost.

In a first aspect, an embodiment of the present invention provides a liquid level monitoring device for measuring the liquid level of a liquid in a liquid storage device, and the liquid level monitoring device includes a liquid level monitoring module and a control module;

The liquid level monitoring module is arranged in the liquid storage device and is electrically connected to the control module. The liquid level monitoring module includes a housing, a float disposed inside the housing, and a float disposed on the float The liquid level sensing block on the bottom of the housing is provided with a liquid inlet, which is used to balance the liquid level in the housing and the liquid storage device, and the float is used to float on the liquid surface. The liquid level sensing block is electrically connected to the control module and used to detect liquid level information and provide liquid level information to the control module;

The control module is arranged outside the liquid storage device and is used for receiving the liquid level information.

Optionally, the liquid level monitoring module further includes: a pillar arranged in the housing, the float has a through hole, the pillar passes through the through hole of the float, and the diameter of the through hole of the float is larger than the The diameter of the strut so that the float slides up and down the strut.

Optionally, the float includes a suction block and a suction block spring matched with the suction block;

The inner side of the housing is provided with an electromagnetic position module that cooperates with the suction block, the electromagnetic position module is electrically connected to the control module, and the electromagnetic control module generates magnetic force to attract the suction block after being powered on. The liquid level sensing block measures liquid level information and provides liquid level information to the control module.

Optionally, the surface of the suction block combined with the electromagnetic position module is provided with a zigzag engaging surface.

Optionally, the liquid level monitoring module further includes: a solenoid valve arranged at the liquid inlet, the solenoid valve is electrically connected to the control module, and the solenoid valve is used for controlling Turn on the power to close the liquid inlet, or turn off the power to open the liquid inlet.

Optionally, a relay is provided between the control module and the solenoid valve, and the relay is used to transmit the solenoid valve control signal generated by the control module to the solenoid valve.

Optionally, the liquid level monitoring module further includes: an upper liquid level limit switch and a lower liquid level limit switch arranged on the side wall of the housing, the upper liquid level limit switch and the lower liquid level limit switch are respectively electrically connected to the control modules, and the upper liquid level limit switch is used to provide the control module with an upper limit signal of the liquid level when the height of the liquid level is greater than or equal to the height of the upper liquid level limit switch. The lower liquid level limit switch is used to provide the lower limit signal of the liquid level to the control module when the height of the liquid level is less than or equal to the height of the lower liquid level limit switch;

The control module is also used for generating and outputting a warning signal when receiving the upper limit signal or the lower limit signal.

Optionally, the liquid level monitoring device also includes:

The warning module is communicatively connected with the control module, and is used to issue an alarm reminder according to the warning signal.

Optionally, the warning module includes one or more of indicator lights, buzzers or other display devices.

In a second aspect, an embodiment of the present invention further provides a vehicle oil level monitoring system, comprising the above-mentioned liquid level monitoring device and a vehicle fuel tank, the liquid level monitoring device is used for monitoring the fuel level of the vehicle fuel tank.

Optionally, the vehicle oil tank is an engine oil tank or a gearbox lubricating oil tank.

An embodiment of the present invention provides a liquid level monitoring device. The liquid level monitoring device includes a liquid level monitoring module arranged in the liquid storage device and a control module arranged outside the liquid storage device; The float inside the body and the liquid level sensing block arranged on the float, the bottom of the shell is provided with a liquid inlet, the bottom surface of the shell is in contact with the bottom surface of the liquid storage device and the shell is fixed, and the liquid inlet is used to balance the The liquid level in the shell and the liquid storage device, the float floats on the liquid surface, the liquid level sensing block is electrically connected to the control module and used to detect liquid level information and provide liquid level information to the control module, so as to realize accurate monitoring of liquid storage at low cost The level of liquid in the device.

Description of drawings

Fig. 1 is a schematic structural diagram of a liquid level monitoring device provided in Embodiment 1 of the present invention;

Fig. 2 is a schematic structural diagram of a liquid level monitoring device provided in Embodiment 2 of the present invention;

Fig. 3 is a schematic structural view of the zigzag joint surface of the suction block and the electromagnetic position module provided by the second embodiment of the present invention;

Fig. 4 is a schematic structural diagram of a vehicle oil level monitoring system provided by Embodiment 3 of the present invention;

5 is a schematic structural diagram of the vehicle oil level monitoring system when the electromagnetic position module is engaged with the suction block after the vehicle is powered on in the third embodiment of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention. In addition, it should be noted that, for the convenience of description, only part of but not all structures related to the present invention are shown in the drawings, wherein the same or similar symbols represent the same or similar elements or elements with the same or similar functions .

Embodiment one

Figure 1 is a schematic structural diagram of a liquid level monitoring device provided by Embodiment 1 of the present invention. This embodiment is applicable to monitoring the liquid level of a liquid storage device. The liquid level monitoring device includes a liquid level monitoring module 1 and a control module 2. As shown in Figure 1, the liquid level monitoring module 1 is arranged in the liquid storage device and connected to the control module 2. The liquid level monitoring module 1 includes a housing 11, a float 12 arranged inside the housing 11, and a float 12 arranged on the The liquid level sensing block 13 on the top, the bottom of the housing 11 is provided with a liquid inlet 14, which is used to balance the liquid level in the housing 11 and the liquid storage device, the float 12 is used to float on the liquid surface, and the liquid level sensing Block 13 is electrically connected to the control module 2 and is used for detecting liquid level information and providing liquid level information to the control module 2; the control module 2 is arranged outside the liquid storage device for receiving liquid level information.

It can be understood that when the float 12 is placed in the liquid to be tested, it can float on the liquid surface, and the liquid level sensing block 13 can measure the liquid level information by means of an infrared measurement module, an electromagnetic measurement module, etc. The specific selection of the liquid level sensing block is not limited in this embodiment of the present invention.

Exemplarily, the housing 11 may be a barrel-shaped shell with the bottom surface removed, and its shape may be a cylinder, a square column, etc., which is not specifically limited in this embodiment of the present invention. The working process of the liquid level monitoring device 1 is as follows: when the liquid storage device stores liquid, since the bottom end of the housing 11 is provided with a liquid inlet 14, the space inside and outside the housing 11 forms a connector so that the liquid level of the liquid storage device is in contact with the housing. The liquid level in the body 11 is at the same height. At this time, the float 12 floats on the liquid surface, and the liquid level sensing block 13 arranged on the float 12 can measure the liquid level information in the housing 11 and transmit the liquid level information to the control module 2 , so that the control module 2 can obtain the liquid level information in the liquid storage device.

The liquid level monitoring device provided in this embodiment includes a liquid level monitoring module disposed in the liquid storage device and a control module disposed outside the liquid storage device; the liquid level monitoring module includes a housing, a float disposed inside the housing, and a device The liquid level sensing block on the float, the bottom of the shell is provided with a liquid inlet, the bottom surface of the shell is in contact with the bottom surface of the liquid storage device and the shell is fixed, and the liquid inlet is used to balance the inside of the shell and the inside of the liquid storage device The liquid level, the float floats on the liquid surface, the liquid level sensing block is electrically connected with the control module and used to detect the liquid level information and provide the liquid level information to the control module, there is no need to set up a transmitting and receiving device similar to ultrasonic detection, the structure is simple, The liquid level of the liquid in the liquid storage device can be accurately monitored at low cost.

Embodiment two

Fig. 2 is a schematic structural diagram of a liquid level monitoring device provided by Embodiment 2 of the present invention. This embodiment is based on the above embodiment, as shown in Fig. 2 , optionally, the liquid level monitoring module 1 also includes : the pillar 15 arranged in the housing 11, the float 12 has a through hole, the pillar 15 runs through the through hole of the float 12, the diameter of the through hole of the float 12 is greater than the diameter of the pillar 15, so that the float 12 slides up and down along the pillar 15. The setting of the pillar 15 can prevent the float 12 from floating in the horizontal direction, make the float 12 more stable, and improve the measurement accuracy of the liquid level sensing block 13 .

Optionally, the float 12 includes a suction block 16 and a suction block spring 17 matched with the suction block; the inside of the housing 11 is provided with an electromagnetic position module 18 matched with the suction block 16, the electromagnetic position module 18 is electrically connected with the control module 12, and the electromagnetic position module 18 is electrically connected to the control module 12. After the control module 18 is powered on, it generates magnetic force to attract the suction block 16 so that the liquid level sensing block 13 measures the liquid level information and provides the control module 12 with liquid level information.

It can be understood that the suction block 16 can be formed by magnetic materials, such as magnetic metal materials such as iron, cobalt, nickel, etc., the electromagnetic position module 18 can be an electromagnet, and the control module 2 controls whether the electromagnetic position module 18 is energized or not, and the electromagnetic position When the module 18 is powered on, it can generate magnetism to attract the suction block 16 , and when the electromagnetic position module 18 is powered off, its magnetism disappears to disconnect the suction block 16 . Due to the shaking of the liquid storage device and other reasons, the liquid level will change, resulting in inaccurate measurement of the liquid level information by the liquid level sensing block 13. Through the setting of the suction block 16 and the electromagnetic position module 18, when the liquid level in the liquid storage device fluctuates, through The control module 2 controls the electromagnetic position module 18 to suck the suction block 106, which helps to improve the accuracy of the liquid level sensing block 13 in measuring the liquid level.

Optionally, the surface of the suction block 16 combined with the electromagnetic position module 18 is provided with a zigzag engaging surface. Figure 3 is a schematic diagram of the structure of the zigzag joint surface of the suction block and the electromagnetic position module. By setting the zigzag meshing surface, the joint area between the suction block 16 and the electromagnetic position module 18 can be increased to ensure the suction force and increase the force of the float. Stability, improve the accuracy of measuring liquid level of the liquid level sensing block.

Optionally, continuing to refer to FIG. 2 , the liquid level monitoring module 1 further includes: a solenoid valve 19 disposed at the liquid inlet 14, the solenoid valve 19 is electrically connected to the control module 2, and the solenoid valve 19 is used for controlling Turn on the power to close the liquid inlet 14, or cut off the power to open the liquid inlet 14.

It can be understood that the solenoid valve 19 can be a normally-on solenoid valve, the default state is the conduction state, and it is in the closed state after being energized. When the liquid level in the liquid storage device fluctuates, the control module 2 energizes the solenoid valve 19 to close the inlet Liquid port 14, the liquid transmission path between the liquid storage device and the housing 11 is cut off, which can prevent the liquid flow between the liquid storage device and the housing 11, and at the same time, the control module 2 controls the electromagnetic position module 18 to suck the suction block 16, It helps to improve the accuracy of measuring the liquid level by the liquid level sensing block 13 .

Optionally, a relay 3 is provided between the control module 2 and the solenoid valve 19 , and the relay 3 is used to transmit the solenoid valve control signal generated by the control module 2 to the solenoid valve 19 .

Optionally, the liquid level monitoring module 1 further includes: an upper liquid level limit switch 110a and a lower liquid level limit switch 110b arranged on the side wall of the housing 11, the upper liquid level limit switch 110a and the lower liquid level limit switch 110b are respectively connected to The control module 2 is electrically connected, the upper liquid level limit switch 110a is used to provide the upper limit signal of the liquid level to the control module 2 when the height of the liquid level is greater than or equal to the height of the upper liquid level limit switch 110a, and the lower liquid level limit switch 110b is used for When the height of the liquid level is less than or equal to the height of the lower liquid level limit switch 110b, the lower limit signal of the liquid level is provided to the control module 2; the control module 2 is also used to generate and output a warning signal when the upper limit signal or the lower limit signal is received.

It can be understood that when the height of the liquid level is greater than or equal to the height of the upper liquid level limit switch 110a, the liquid level sensing block 13 on the float 12 will come into contact with the upper liquid level limit switch 110a, and the upper liquid level limit switch 110a will generate a The upper limit signal is transmitted to the control module 2, indicating that the liquid level has reached or exceeded the upper limit; when the height of the liquid level is less than or equal to the height where the lower liquid level limit switch 110b is located, the liquid level sensing block 13 on the float 12 will be in contact with the lower liquid level limit When the switch 110b contacts, the lower liquid level limit switch 110b generates a lower limit signal and transmits it to the control module 2, indicating that the liquid level has reached or is less than the lower limit.

For liquid storage devices in practical applications, for example, for liquid storage tanks that need to be transported long distances, the upper limit of the liquid level needs to be set to ensure safety during transportation; the upper limit of the oil level of the vehicle fuel tank needs to be set to ensure safety, and the lower limit of the oil level is set to remind Users refuel in time. Through the setting of the upper liquid level limit switch 110a and the lower liquid level limit switch 110b, it can be reminded in time when the liquid level is abnormal, which increases the scope of application of the liquid level monitoring device.

Optionally, the liquid level monitoring device further includes: a warning module 4, which is communicatively connected with the control module 2, and is used to issue an alarm reminder according to the warning signal. The warning module 4 includes one or more of indicator lights, buzzers or other display devices. Through the setting of the warning module 4, a reminder is issued when the liquid level of the liquid storage device is abnormal, which is beneficial for the user to deal with it in time.

Embodiment Three

FIG. 4 is a schematic structural diagram of a vehicle oil level monitoring system provided by Embodiment 3 of the present invention. This embodiment may provide a specific example based on the foregoing embodiments.

The vehicle oil level monitoring system provided in this embodiment includes a liquid level monitoring device and a vehicle fuel tank, wherein the liquid level monitoring device is used to monitor the fuel level of the vehicle fuel tank.

Optionally, the vehicle oil tank is an engine oil tank or a transmission lubricating oil tank.

As shown in Figure 4, the liquid level monitoring device includes a liquid level monitoring module 10 and a control module 20; the liquid level monitoring module 10 is arranged in the fuel tank of the vehicle, and is connected with the control module 20, and the liquid level monitoring module 10 includes a housing 101, a set The float 102 inside the housing 101 and the liquid level sensing block 103 arranged on the float 102, the bottom end of the housing 101 is provided with a liquid inlet 104, which is used to balance the liquid level in the housing 101 and the vehicle fuel tank, The float 102 is used to float on the liquid surface, and the liquid level sensing block 103 is electrically connected to the control module 20 and used to detect liquid level information and provide liquid level information to the control module 20; the control module 20 is arranged outside the liquid storage device for receiving Level information.

Optionally, the liquid level monitoring module 10 further includes: a pillar 105 arranged in the housing 101, the float 102 has a through hole, the pillar 105 passes through the through hole of the float 102, the diameter of the through hole of the float 102 is larger than the diameter of the pillar 105, To make the float 102 slide up and down along the support 105 .

Optionally, the float 102 includes a suction block 106 and a suction block spring 107 cooperating with the suction block; an electromagnetic position module 108 cooperating with the suction block 106 is arranged inside the housing 101, the electromagnetic position module 108 is electrically connected with the control module 20, and the electromagnetic position module 108 is electrically connected to the control module 20. After the control module 108 is powered on, it generates magnetic force to attract the suction block 106 , so that the liquid level sensing block 103 measures the liquid level information and provides the liquid level information to the control module 20 .

Optionally, the surface of the suction block 106 combined with the electromagnetic position module 108 is provided with a zigzag engaging surface.

Optionally, the liquid level monitoring module 10 also includes: a solenoid valve 109 arranged at the liquid inlet 104, the solenoid valve 109 is electrically connected to the control module 20, and the solenoid valve 109 is used to energize under the control of the control module 20 to close the inlet The liquid inlet 104, or cut off the power to conduct the liquid inlet 104.

Optionally, a relay 30 is provided between the control module 20 and the solenoid valve 109 , and the relay 30 is used to transmit the solenoid valve control signal generated by the control module 20 to the solenoid valve 109 .

Optionally, the liquid level monitoring module 10 also includes: an upper liquid level limit switch 1010a and a lower liquid level limit switch 1010b arranged on the side wall of the housing 101, the upper liquid level limit switch 1010a and the lower liquid level limit switch 1010b are respectively connected to The control module 20 is electrically connected, the upper liquid level limit switch 1010a is used to provide the upper limit signal of the liquid level to the control module 20 when the height of the liquid level is greater than or equal to the height of the upper liquid level limit switch 1010a, and the lower liquid level limit switch 1010b is used for When the height of the liquid level is less than or equal to the height of the lower liquid level limit switch 1010b, the lower limit signal of the liquid level is provided to the control module 20; the control module 20 is also used to generate and output a warning signal when the upper limit signal or the lower limit signal is received.

Optionally, the liquid level monitoring device further includes: an alarm module 40, which is in communication connection with the control module 20, and is used to issue an alarm reminder according to the alarm signal. The warning module 40 includes one or more of an indicator light, a buzzer or other display devices.

It can be understood that the control module 20 and the warning module 40 can be connected through the controller area network CAN bus, and the control module 20 can also be connected to a display device such as a vehicle instrument, so that the display device displays an oil level signal or a warning signal.

The implementation process of the vehicle oil level monitoring system provided in this embodiment is as follows:

The current state of the vehicle key is obtained through the control module 20. If the control module 20 judges that the vehicle key is in the closed state, that is, when the vehicle is not running, the oil level in the fuel tank is in a static state, the solenoid valve 109 is normally open, and the space inside and outside the housing 101 forms a connector to enable The oil level in the fuel tank is equal to the oil level in the housing 101, and the float 102 is in a free state. As shown in FIG. oil level information in the

If the control module 20 acquires the vehicle key open state, and the vehicle has just been powered on and is not running, and the oil level in the fuel tank is in a static state, the control module 20 closes the solenoid valve through the relay 30, preventing the oil from flowing between the fuel tank and the housing 101, and at the same time The control module 20 controls the electromagnetic position module 108 to suck the suction block 106, as shown in Figure 5, the oil level information in the casing 101 is measured by the liquid level sensing block 103 and transmitted to the control module 20, and the oil level in the fuel tank is obtained information. Since the electromagnetic position module 108 absorbs the suction block 106, the fluctuation of the oil fluid will not cause the movement of the float 102 during the operation of the vehicle, which can eliminate the influence of the fluctuation of the oil level of the fuel tank during the operation of the vehicle and improve the measurement accuracy.

When the oil level of the fuel tank is greater than or equal to the height of the upper liquid level limit switch 1010a, the liquid level sensing block 103 on the float 102 will contact the upper liquid level limit switch 1010a, and the upper liquid level limit switch 1010a generates an upper limit signal and transmits To the control module 20, indicating that the liquid level has reached or exceeded the upper limit; when the height of the fuel tank level is less than or equal to the height where the lower liquid level limit switch 1010b is located, the liquid level sensing block 103 on the float 102 will be in contact with the lower liquid level limit switch 1010b , the lower liquid level limit switch 1010b generates a lower limit signal and transmits it to the control module 20, indicating that the liquid level has reached or is less than the lower limit. The control module 20 generates an alarm signal and transmits it to the alarm module 40 to issue an alarm reminder, prompting the user to deal with it in time.

Note that the above are only preferred embodiments of the present invention and applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and can also include more other equivalent embodiments without departing from the concept of the present invention, and the present invention The scope is determined by the scope of the appended claims.

Claims (11)

1. A liquid level monitoring device for measuring the liquid level of liquid in a liquid storage device, characterized in that the liquid level monitoring device includes a liquid level monitoring module and a control module; The liquid level monitoring module is arranged in the liquid storage device and is electrically connected to the control module. The liquid level monitoring module includes a housing, a float disposed inside the housing, and a float disposed on the float The liquid level sensing block on the bottom of the housing is provided with a liquid inlet, which is used to balance the liquid level in the housing and the liquid storage device, and the float is used to float on the liquid surface. The liquid level sensing block is electrically connected to the control module and used to detect liquid level information and provide liquid level information to the control module; The control module is arranged outside the liquid storage device and is used for receiving the liquid level information. 2. The liquid level monitoring device according to claim 1, wherein the liquid level monitoring module further comprises: a pillar arranged in the housing, the float has a through hole, and the pillar passes through the float The diameter of the through hole of the float is larger than the diameter of the pillar, so that the float slides up and down along the pillar. 3. The liquid level monitoring device according to claim 1, wherein the float comprises a suction block and a suction block spring matched with the suction block; The inner side of the housing is provided with an electromagnetic position module that cooperates with the suction block, the electromagnetic position module is electrically connected to the control module, and the electromagnetic control module generates magnetic force to attract the suction block after being powered on. The liquid level sensing block measures liquid level information and provides liquid level information to the control module. 4. The liquid level monitoring device according to claim 3, characterized in that, the surface of the suction block combined with the electromagnetic position module is provided with a zigzag engaging surface. 5. The liquid level monitoring device according to claim 1, wherein the liquid level monitoring module further comprises: A solenoid valve arranged at the liquid inlet, the solenoid valve is electrically connected to the control module, and the solenoid valve is used to energize to close the liquid inlet under the control of the control module, or to cut off the power To lead through the liquid inlet. 6. The liquid level monitoring device according to claim 5, wherein a relay is arranged between the control module and the solenoid valve, and the relay is used to transmit the solenoid valve control signal generated by the control module to the solenoid valve. 7. The liquid level monitoring device according to any one of claims 1 to 6, wherein the liquid level monitoring module further comprises: The upper liquid level limit switch and the lower liquid level limit switch arranged on the side wall of the housing, the upper liquid level limit switch and the lower liquid level limit switch are respectively electrically connected to the control module, and the upper liquid level limit switch The level limit switch is used to provide the upper limit signal of the liquid level to the control module when the height of the liquid level is greater than or equal to the height of the upper liquid level limit switch, and the lower liquid level limit switch is used to provide the upper limit signal of the liquid level when the height of the liquid level is less than or equal to Provide the lower limit signal of the liquid level to the control module when the height of the lower liquid level limit switch is located; The control module is also used for generating and outputting a warning signal when receiving the upper limit signal or the lower limit signal. 8. The liquid level monitoring device according to claim 7, further comprising: The warning module is communicatively connected with the control module, and is used to issue an alarm reminder according to the warning signal. 9. The liquid level monitoring device according to claim 8, wherein the warning module includes one or more of an indicator light, a buzzer or other display devices. 10. A vehicle fuel level monitoring system, characterized by comprising the liquid level monitoring device according to any one of claims 1 to 9 and a vehicle fuel tank, the liquid level monitoring device being used to monitor the fuel level of the vehicle fuel tank. 11. The vehicle oil level monitoring system according to claim 10, wherein the vehicle oil tank is an engine oil tank or a gearbox lubricating oil tank.