JPH0353687Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> This invention relates to oil filters for automobiles, etc.

<Conventional technology> Deterioration of engine oil is usually determined by observing the color of the engine oil attached to the oil gauge, but an alternative method is to measure the decrease in dielectric constant due to deterioration of engine oil by measuring capacitance. One possible method is to use a type sensor.

In that case, in order to secure the necessary capacitance, large electrode areas must be placed opposite each other at a narrow interval, so it is recommended to install the sensor inside the oil pan in order to provide enough space to install a large electrode plate. Conceivable.

<Problems to be Solved by the Invention> According to the above configuration in which the sensor is installed in the oil pan, oil sludge cannot be avoided from adhering to the electrodes. Since the spacing between the electrode plates is narrow, as the oil sludge builds up, the oil between the electrode plates will no longer flow, making accurate detection impossible.
Therefore, in order to function as a sensor until the end of the car's lifespan, there is a problem in that periodic cleaning or replacement of the electrode plate is required to remove oil sludge adhering to the electrode plate, and the oil pan Unlike other sensors and plugs, it is difficult to attach and detach if installed inside the sensor.

Furthermore, since it is difficult to maintain a short distance between a pair of electrode plates, it has been necessary to further increase the electrode area.

<Means for solving the problem> This invention is an oil filter in which a sheet-like filter medium is installed in the housing, and porous electrode sheets are attached along both sides of the filter medium, so that an oil deterioration sensor with a built-in oil filter is installed. This is a configuration of a filter.

<Operation of the invention> In this invention, since the electrode sheets are attached along both sides of the filter medium, an extremely wide electrode area can be obtained. Moreover, the filter medium functions as a spacer that keeps the distance between both electrodes at a small distance. Therefore,
Since the absolute value of the capacitance detected between the electrodes becomes large and the change in the dielectric constant of the oil is detected as an extremely large value, it becomes easy to determine whether the oil has deteriorated. Furthermore, since the sensor is built into the oil filter, the sensor must be replaced every time the oil filter is replaced, and there is no need to clean the electrodes.

Examples of this invention will be described below based on the drawings.

<Example> In FIG. 1, a filter medium 2 folded into a chrysanthemum shape is installed in a housing 1, and porous electrodes constituting a capacitance sensor are arranged on both the inside and outside surfaces of the filter medium 2. Sheets 3 and 4 are layered. The upper and lower ends of the filter medium 2 are closed with insulating plates 5 and 6.

The electrode sheets 3 and 4 are metal foils made of iron or the like, and are folded into a chrysanthemum shape like the filter medium 2. The porosity is determined by balancing the required electrode area and pressure loss, but if it is about 30%, pressure loss will not be a problem. One ends of lead wires 7 and 8 are attached to the electrode sheets 3 and 4, and the other ends are taken out of the housing 1. The change in capacitance between the two electrodes can be measured remotely using the lead wires 7 and 8, and oil deterioration can be detected.

In the figure, 9 is an oil inlet and 10 is an oil outlet.

In order to manufacture the oil filter with a built-in oil deterioration sensor of this embodiment, the electrode sheets 3 and 4 may be layered on both sides of the filter medium 2 in advance, and the filter medium and the electrode sheets may be simultaneously folded into a chrysanthemum shape.

According to the above embodiment, since the electrode sheets 3 and 4 are layered over the entire surface of the filter medium, an extremely wide electrode area can be obtained, similar to when the electrodes are installed inside the oil bun. Also, the electrode sheets 3 and 4 are connected to the filter medium 2.
Since it functions as a reinforcing material to prevent deformation of the filter material, there is no need for an inner tube that was conventionally attached to the inside of the filter material for reinforcement.

Note that it is not an essential condition that the electrode sheet be layered over the entire surface of the filter medium. Further, the filter medium and the electrode sheet do not need to be fixed to each other.

In the above embodiment, the sheet-like filter medium was folded into a chrysanthemum shape, but the sheet-like filter medium may have other shapes such as a layered chrysanthemum-like sheet or a spirally wound sheet. Even if the filter medium has the shape shown in FIG.

<Effects of the invention> According to this invention, since electrode sheets are layered on the inner and outer surfaces of the filter medium, an extremely wide electrode area can be obtained. Furthermore, since the filter medium functions as a spacer that maintains the distance between the electrode sheets, the distance between the two electrode sheets is maintained at a small distance equal to the thickness of the filter medium, and there is no fear that the two electrode sheets will come into contact with each other. Furthermore, since the filter medium always serves as a passage for oil,
A certain amount of oil always exists and flows between the two electrodes. Therefore, the absolute value of the capacitance between the electrode sheets becomes large, and the change in dielectric constant due to oil deterioration can be understood as a large numerical change, making it possible to easily and accurately judge the degree of oil deterioration. I can do it.

Furthermore, since the electrode sheet is integrated within the oil filter, the electrode sheet will also be replaced when the oil filter is replaced. Therefore,
There is no need to remove oil sludge adhering to the electrode sheet, and the electrode sheet is always maintained in good condition.

As described above, according to the oil filter with built-in sensor of this invention, deterioration of oil can be detected with high reliability.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of this invention, and FIG. 2 is a partially enlarged sectional view of the filter medium. 1... Housing, 2... Filter medium, 3, 4... Electrode sheet.

Claims (1)

[Claims for Utility Model Registration] 1. In an oil filter in which a sheet-like filter medium is mounted inside a housing, a porous electrode sheet is attached along both sides of the filter medium, and lead wires are provided from both electrodes to the outside of the housing so that oil can be filtered. An oil filter with a built-in oil deterioration sensor. 2. The oil filter with a built-in oil deterioration sensor according to claim 1, wherein the electrode sheet is attached to the entire surface of the filter medium. 3. The oil filter with a built-in oil deterioration sensor according to claim 1, wherein the sheet-like filter medium is folded in the shape of a chrysanthemum.