JP3665686B2 - Oil changer - Google Patents

Description

[0001]
[Industrial application fields]
TECHNICAL FIELD The present invention relates to an oil changer that is installed mainly in a gas station or a maintenance shop and that changes oil used for power steering oil of an automobile.
[0002]
[Prior art]
Conventionally, for example, as a method of replacing the oil in the reserve tank for power steering oil, after using an existing engine oil changer and removing it with a pump, the pump is used while visually checking the liquid level position. Injecting the oil gradually or weighing it with a weight cell such as a load cell provided separately, or automatically injecting the same amount of new oil, or a dedicated machine with only the function of extraction Then, after draining the waste oil in the reserve tank with a pump, gradually injecting new oil with an oil mug etc. while visually checking the liquid level position, and a pump and nozzle with relatively small capacity After removing the waste oil with a special machine equipped with a light sensor, the method of stopping the injection when the liquid level rises to the sensor part at the time of new oil injection, etc. It is to have.
[0003]
[Problems to be solved by the invention]
However, in the existing engine oil changer, since the amount of oil to be changed is considerably large, the pump capacity of the changer is relatively large. However, because the capacity of the reserve tank for power steering oil is small, no matter how much the load cell is used to make the extraction amount and the injection amount the same, the injection amount will go too far and overflow when injecting new oil There was a risk of waking up.
[0004]
In addition, power steering oil is not an oil that needs to be changed as often as engine oil because of its nature, so even if it reduces the pump capacity and improves the engine oil changer equipped with a load cell, it is a device that replaces power steering oil. Even if it does, since the cost will become expensive, when it considers the depreciation of an apparatus, it will become something which is not worthy.
[0005]
In addition, in dedicated machines that only perform extraction, not only is it cumbersome to visually check the liquid level during injection, but some reserve tanks are made of resin with the liquid level visible from the side of the tank. There are structures that cannot be seen inside, and even resin-made ones can check the liquid level, but it is very difficult to check the liquid level in a dark place where dirt is attached to the peripheral surface of the tank. Therefore, it is almost impossible to perform accurate injection. Sometimes, as in the case described above, overflow occurs and oil is applied to peripheral devices.
[0006]
Furthermore, if you use a pump with a relatively small capacity and a special machine equipped with a light sensor, it is possible to stop the injection when the new oil level rises to the light sensor. The positional relationship between the optical sensor that detects the liquid level and the nozzle is always constant, and the insertion level of the nozzle, that is, the position of the liquid level at the end of the new oil injection is also determined by the position of the optical sensor. Depending on the situation, the level of the new oil injection liquid may not be the normal height. In this case, when inserting the nozzle before draining the waste oil, the insertion position of the optical sensor should be visually adjusted in advance. Necessity arises.
[0007]
An object of the present invention is to provide an oil changer that can solve the above-mentioned problems.
[0008]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention extracts and accommodates a capacitive liquid level sensor also serving as a nozzle, which is formed into a double cylinder with a constant interval as appropriate, and waste oil in an oil exchanged body. A waste oil tank for storing oil, a new oil tank for storing new oil to be injected into the oil-exchanged body, one connected to the liquid level sensor, the other connected to a reversible pump and pipe switching means A drain and injection pipe connected to the waste oil tank and the new oil tank via the control, and a control means for controlling the reversible pump and the pipe switching means based on a signal from the liquid level sensor. Detecting and storing an initial liquid level of waste oil contained in the oil exchange body when a surface sensor is inserted into the oil exchange body, driving the reversible pump in the extraction direction and A step of switching the pipeline switching means so that only the extraction pipeline is opened, extracting the waste oil in the oil exchanged body into the waste oil tank, and being detected by the liquid level sensor during waste oil extraction. When there is no change in the liquid level, the reversible pump is switched in the injection direction and the conduit switching means is switched so that only the injection conduit is opened, and the new oil in the new oil tank is As the liquid level detected by the liquid level sensor approaches the initial liquid level so as not to overflow from the oil-exchanged body during the step of injecting into the oil-exchanged body and new oil injection, The rotational speed of the reversible pump is gradually reduced, and when the initial liquid level is reached, the reversible pump is stopped and the conduit switching means is switched, and the injection conduit It is an gist thereof is to provide an oil exchange apparatus and a step of closed.
[0009]
[Action]
Before the oil change, the initial liquid level of the waste oil in the oil exchanged body is detected and confirmed by a cylindrical capacitive liquid level sensor that also serves as a nozzle, and is detected by the liquid level sensor when new oil is injected. As the liquid level reached approaches the initial liquid level, the rotational speed of the pump is gradually reduced, and the injection is terminated when the initial liquid level is reached. Regardless of the shape, etc., new oil can be injected accurately to the normal liquid level.
[0010]
In addition, a long hole is drilled in the axial direction of the outer cylinder of the liquid level sensor that also serves as a nozzle, so that oil can easily enter and exit from the long hole into the double cylinder that forms the liquid level sensor. , Can sufficiently follow changes in the liquid level of highly viscous oil.
【Example】
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
[0011]
FIG. 1 is an overall configuration diagram of an oil changer according to an embodiment of the present invention. Here, FIG. 1 is an explanatory diagram when the power steering oil is changed.
[0012]
A waste oil tank 2 for storing the drained waste oil and a new oil tank 3 for storing the new oil to be injected are respectively disposed in the main body 1. And the injection line 5 is connected.
[0013]
The pipes 4 and 5 are provided with solenoid valves 6, 7, 8 and 9, which are pipe switching means, and a reversible pump 10 which can be rotated forward and backward. It is controlled by the control means 11 which consists of this, and it can switch the pipe lines 4 and 5 and can change the rotation direction of the reversible pump 10.
[0014]
Furthermore, both the pipe lines 4 and 5 outside the main body are flexible flexible hoses, and the tips thereof are static nozzles that are also used as nozzles that are formed in a double cylindrical shape with a constant interval as appropriate. It is connected to a capacitive liquid level sensor 12 and is inserted into a power steering oil reserve tank 13 as shown in the figure when oil is changed. By the way, a long hole is bored over substantially the entire length in the axial direction of the outer surface of the liquid level sensor 12, so that even oil with viscosity can easily enter and exit the sensor.
[0015]
FIG. 2 is a cross-sectional view of the main part of the liquid level sensor 12, and the portion that also serves as the nozzle portion is a metallic inner cylinder 14, and the tip of the flexible hose is connected to the root of the inner cylinder 14. Oil extraction and injection can be performed by the inner cylinder 14.
[0016]
Also, metal outer cylinders 15 are fixed to insulating guides 16 and 17 with appropriate intervals on the outer periphery, and these inner cylinders 14 and outer cylinders 15 form so-called capacitors. Thus, oil can quickly enter the inner cylinder 14 through the long hole drilled in the outer cylinder 15, and the capacitance by the capacitor can also change rapidly following the change in the liquid level. It has become.
[0017]
Furthermore, the front ends of the inner cylinder 14 and the outer cylinder 15 are supported by an insulating cylindrical support 18 so that the inner cylinder 14 and the outer cylinder 15 do not short-circuit by touching the metal reserve tank. At the same time, the support 18 is provided with a plurality of holes on the bottom surface and the bottom peripheral surface, and these holes serve as oil passages.
[0018]
Inside the guide 17 is provided an oscillation circuit 19 for repeatedly charging and discharging the inner cylinder 14 and the outer cylinder 15 (electrostatic capacitances of the inner cylinder and the outer cylinder that change with the change of the liquid level). This is a circuit that captures a change in capacity as a change in charge / discharge time interval and outputs the change as a change in pulse signal.) Further, the control means 11 supplies the power supply line 20 to the oscillation circuit 19, and conversely from the oscillation circuit 19. Is provided with a signal line 21 for converting the charge / discharge repetition into the number of pulses and sending it to the control means 11.
[0019]
Next, usage and operation of the embodiment will be described.
[0020]
First, an operator inserts the nozzle level liquid level sensor 12 into the power steering oil reserve tank 13 and presses a start switch (not shown) while the vehicle engine is idling. A pulse signal corresponding to the level of the waste oil in the reserve tank 13 is sent from the oscillation circuit 19 in the level sensor 12 to the control means 11 through the signal line 21 (the device is turned on). When the voltage is always applied to the liquid level sensor 12 through the power line 20 and a pulse signal is sent from the oscillation circuit 19, the control means 11 ignores the signal until the start switch is pressed. The control means 11 stores the number of pulses as the initial liquid level, and the control means 11 7 by opening is driven to rotate in the direction sampling reversible pump 10.
[0021]
Then, the waste oil in the reserve tank 13 is extracted into the waste oil tank 2 through the inner cylinder 14 and the extraction pipe 4, and the extraction process is started.
[0022]
At this time, since the engine of the vehicle is in an idling state as described above, waste oil sent from the hydraulic system of the power steering enters the reserve tank 13, so the waste oil that has circulated through the hydraulic system Is also extracted in this sampling process.
[0023]
Eventually, when the waste oil in the reserve tank 13 decreases and the liquid level falls below the round hole formed in the peripheral surface of the support 18 at the tip of the liquid level sensor 12 (here, the hole opened in the support 18 is only the bottom surface). If this is the case, most of the oil in the hydraulic system will be sucked, and this will have some adverse effects on the hydraulic system. In other words, air is sucked from the inner cylinder 14, and the number of pulses sent from the oscillation circuit 19 to the control means 11 does not change.
[0024]
The control means 11 starts timing with a built-in timer from the time when the number of pulses no longer changes more than a predetermined value. When a predetermined time elapses, the control means 11 determines that sampling is complete, closes the solenoid valves 6 and 7, In addition, the electromagnetic valves 8 and 9 are opened, and the reversible pump 10 is driven to be reversed in the injection direction.
[0025]
Then, new oil in the new oil tank 3 passes through the injection pipe 5 and the inner cylinder 14 and is injected into the reserve tank 13 to start the injection process.
[0026]
When the injection process is started, the liquid level in the reserve tank 13 gradually rises. However, since the inner diameter of the reserve tank 13 is quite thin, the liquid level rise speed is considerably high, and the rotational speed of the reversible pump 10 is increased. If you don't drop it step by step, you risk overflowing.
[0027]
Therefore, in this embodiment, the number of pulses before the liquid level sensor 12 is inserted into the reserve tank 13 (preliminarily registered in the control means) and the number of pulses corresponding to the initial liquid level stored at the time of insertion. The difference is 100%, and when the difference becomes 60% during the injection, the first liquid level is set. The pump rotation speed is reduced to 50% of the initial injection rotation speed, and the difference is 80%. The liquid level is set to two, and thereafter, the pump rotation speed is set to 30% of the initial injection rotation speed until reaching 100%, and the liquid level is gradually increased while the liquid level rising speed is suppressed.
[0028]
Then, when the liquid level eventually reaches the initially stored initial liquid level, the control means 11 receiving the signal closes the electromagnetic valves 8 and 9 and stops the reversible pump 10 to complete the injection process. New oil can be injected up to the same level as the waste oil level that was in the beginning.
[0029]
In this embodiment, the automatic course in which the extraction and injection are automatically continued has been described. However, a single course of manual extraction and injection in which the number of pulses from the liquid level sensor is ignored can be provided. Needless to say.
[0030]
In addition, it is expensive to strictly prevent the mixing of waste oil and new oil during oil exchange, but it may be expensive, but it can also be structured as a separate pump and injection pipe, each with a dedicated pump. Good.
[0031]
【The invention's effect】
As described above, the present invention eliminates the need for visual confirmation when injecting new oil when replacing oil such as power steering oil that does not substantially change the amount of oil unless there is a pipe leak. The oil can be changed accurately in a short time with little trouble from the operator.
In addition, when new oil is injected, control is performed to gradually reduce the rotational speed of the pump, so there is no worry of overflow.
Further, since the nozzle and the liquid level sensor are used in combination, it can be manufactured at a lower cost compared to a conventional load cell or other weight meter.
In addition, since a long hole extending almost the entire length is drilled in the axial direction of the outer cylinder of the liquid level sensor, even a highly viscous material such as oil can easily enter between the inner cylinder and the outer cylinder of the liquid level sensor. Therefore, the followability of the change in the liquid level is very high, and the oil in a tank having a small inner diameter such as a reserve tank for power steering oil can be exchanged.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an oil changer according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a main part of a liquid level sensor of the same apparatus.
[Explanation of symbols]
2 Waste oil tank 3 New oil tank 4 Extraction pipeline 5 Injection pipeline 6, 7, 8, 9 Switching means 10 Reversible pump 11 Control means 12 Liquid level sensor 14 Inner cylinder 15 Outer cylinder

Claims (2)

Capacitance-type liquid level sensor also serving as a nozzle, which is formed into a double cylinder with a constant interval as appropriate,
A waste oil tank for extracting and storing waste oil in the oil exchanged body;
A new oil tank for storing new oil to be injected into the oil exchange body,
One is connected to the liquid level sensor, and the other is connected to the waste oil tank and the new oil tank through a reversible pump and a pipe switching means, and a sampling and injection pipe,
It comprises a control means for controlling the reversible pump and the pipe switching means based on a signal from the liquid level sensor,
Detecting and storing an initial liquid level of waste oil contained in the oil exchange body when the liquid level sensor is inserted into the oil exchange body;
Driving the reversible pump in the extraction direction and switching the pipeline switching means so that only the extraction pipeline is opened, and extracting the waste oil in the oil exchanged body into the waste oil tank;
When there is no change in the liquid level detected by the liquid level sensor during waste oil extraction, the reversible pump is switched in the injection direction and the pipeline switching means is switched so that only the injection pipeline is opened. And the step of injecting new oil in the new oil tank into the oil-exchanged body and the liquid level detected by the liquid level sensor so as not to overflow from the oil-exchanged body during new oil injection As the level approaches the initial liquid level, the rotational speed of the reversible pump is gradually reduced. When the initial liquid level is reached, the reversible pump is stopped and the line switching means is switched, and the injection is performed. An oil changer comprising: a step of closing the pipe.   The oil changer according to claim 1, wherein a long hole extending substantially along the entire length is formed in the axial direction of the outer cylinder surface of the liquid level sensor.

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