JP2642304B2 - Oil deterioration detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil deterioration detecting device for optically detecting a deterioration state of a lubricating oil of an internal combustion engine for an automobile, for example.

[0002]

2. Description of the Related Art For example, there has been a demand for an on-vehicle type oil deterioration detecting device capable of detecting a deterioration state of lubricating oil of an internal combustion engine for a vehicle in a normal engine use state. For example, JP-A-63-553
A light transmission type as described in JP-A No. 18 and the like is known. For example, a sampled oil is interposed between a light emitting unit that emits infrared light or visible light and a light receiving unit, and the degree of deterioration is detected based on the transmittance.

Here, the oil to be detected is held as follows:
Generally, it is made of a pair of translucent plate members. That is, as illustrated in FIG. 5, a pair of translucent plate members 21 and 22 made of glass or synthetic resin or the like that can transmit infrared light for measurement or the like are arranged in parallel to face each other, and between them. An oil passage 23 for measurement is formed at a predetermined interval, and communicates with an oil inlet pipe 25 and an oil outlet pipe 26 provided in a casing 24. The measurement oil passage 23 is formed in a planar shape along a plane orthogonal to the optical axis between a light emitting unit and a light receiving unit (not shown). Reference numeral 27 denotes a condenser lens that collects light from the light emitting unit. In addition, the plate-like member 21,
Since the hydraulic pressure acts on the annular member 22, the annular members 32, 33 are fixedly held by retainers 30, 31 via seal members 28, 29 as shown in FIG.
2 and 33 via the sealing members 34 and 35
4 and the oil inlet pipe 2
5. Connect the oil outlet pipe 26 to the sealing members 36 and 37, respectively.
It is made to seal with it. In order to increase the accuracy of the deterioration determination, the plate members 21 and
It is desirable to reduce the thickness of the plate 2 and to set the interval between the measurement oil passages 23 to be small.

[0004]

As described above, in the conventional oil deterioration detecting device, a pair of plate members 21 and
2, the measurement oil passage 23 is formed in a flat shape, so that it is difficult to connect the oil passage 23 to the lubrication system oil pipe, and a large number of seal members such as the seal members 28 and 29 are inevitably required. As a result, not only does the configuration become complicated and the cost rises, but also in an environment where it is difficult to ensure pressure resistance and sealability and the internal combustion engine is constantly subject to vibration, its reliability is reduced.

In an internal combustion engine for an automobile, for example,
Although a large oil pressure of about 6 kg / cm ² acts, it is structurally difficult to ensure sufficient pressure resistance against such oil pressure, and it is necessary to provide a decompression device on the upstream side to introduce the oil once depressurized. there were.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention relates to an oil deterioration detecting device for detecting the degree of oil deterioration based on the transmittance of oil between a light emitting unit and a light receiving unit. And an outer portion made of a soft synthetic resin that is disposed along a direction orthogonal to the optical axis, has ends connected to an oil inlet pipe and an oil outlet pipe, and passes light for measurement. A tube is formed in advance into a flat tube shape having parallel wall surfaces facing each other at a predetermined interval, and the parallel surface is inserted into a portion of the outer tube which intersects with the optical axis in a posture orthogonal to the optical axis. In addition, a rigid inner tube having a window hole formed at a position on the optical axis, and a portion intersecting the optical axis of the outer tube into which the inner tube is inserted are attached to both the optical axis direction. It is characterized by comprising a bracket for fixing to clamped from.

[0007]

[Function] Since the outer tube constituting the oil passage is soft, the inner tube is inserted into the inner tube, and the inner tube is clamped from the outside by the bracket.
The outer tube itself has a flat shape along the inner tube. Then, the outer tube is connected to the oil inlet pipe and the oil outlet pipe, and the oil to be measured flows through the inside thereof. Here, since the connection between the outer tube and the oil inlet tube and the oil outlet tube is a connection between the soft tube and the tube, a complicated seal is not required.

[0008] The light that has exited the light emitting section traverses the flat outer tube through the window hole of the inner tube and reaches the light receiving section. The thickness of the oil layer through which this light passes is accurately secured by the rigid inner tube.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 2 shows an embodiment of an oil deterioration detecting apparatus according to the present invention. An oil inlet pipe 2 is provided at one end of an elongated base block 1 and an oil outlet pipe 3 is provided at the other end. The light emitting unit 4 and the light receiving unit 5 are arranged so as to be fixed and sandwich the center of the base block 1. The light emitting section 4 emits infrared light or visible light suitable for deterioration measurement, has a condensing lens (not shown) on the front surface, and emits measurement light along an optical axis L in the figure. It has become.

An outer tube 6 made of a soft synthetic resin that transmits light for measurement, for example, transparent vinyl chloride, is connected between the oil inlet tube 2 and the oil outlet tube 3. That is, the ends of the oil inlet pipe 2 and the oil outlet pipe 3 are inserted into the inner peripheral sides of both ends of the outer tube 6, and sealed by the elasticity of the outer tube 6 itself. The outer tube 6 may be tightened with an appropriate hose clamp if necessary.

As shown in FIGS. 1 and 3, the central portion of the outer tube 6 sandwiched between the light emitting section 4 and the light receiving section 5 has a flat cross section as if crushed from the direction of the optical axis L. The flat portion 6a is formed by a pair of substantially L-shaped brackets 7.
It is sandwiched between. Specifically, the outer tube 6
A short inner tube 8 previously formed into a flat tube shape is inserted into the center of the inner tube 8.
The bracket 7 clamps the outer tube 6 from the outside while sandwiching the inner tube. The inner tube 8 is formed by flattening a metal pipe such as stainless steel or copper having rigidity necessary for maintaining a cross-sectional shape, and opposes each other with a predetermined distance d as shown in FIG. Circular window holes 9 are formed at the center of the parallel plane, corresponding to the optical axis L, having parallel wall portions 8a, 8a. The distance d is set, for example, to about 0.2 to 0.5 mm.

By inserting the inner tube 8,
The soft outer tube 6 is partially connected to the inner tube 8.
Becomes a flat shape along the outer shape of. The pair of brackets 7 are set at holding intervals in consideration of the outer shape of the flat inner tube 8 and the thickness of the outer tube 6, and are provided between flat holding surfaces 7a, 7a facing each other. The outer tube 6 is pushed in together with the inner tube 8. As a result, the outer tube 6 is brought into pressure contact with the parallel wall portions 8a, 8a of the inner tube 8 without any gap. Also, the holding surface 7 of the bracket 7
a and 7a are arranged so as to be orthogonal to the optical axis L,
Therefore, the parallel walls 8a, 8a of the inner tube 8 are held in a posture orthogonal to the optical axis L. Each bracket 7 has a slit-shaped notch 10 at a position on the optical axis L corresponding to the window hole 9.

In the above configuration, a part of the oil is guided to the oil inlet pipe 2 and flows out to the oil outlet pipe 3 through the outer tube 6, for example, in a form bypassed from a lubrication system of the internal combustion engine. Then, when flowing through the flat flow path in the inner tube 8, the transmittance of the light emitting unit 4 and the light receiving unit 5 due to infrared rays or the like is measured, and oil deterioration is determined.

Here, in the above configuration, since a very thin flow path is accurately formed by the inner tube 8, the detection accuracy is the same as that in the case where the oil passage for measurement is formed by a pair of plate members as in the prior art. Can be secured.

Since the thin outer flow path for measurement is formed by deforming the soft outer tube 6 flat, the connection structure and the seal between the oil inlet pipe 2 and the oil outlet pipe 3 are very small. It is simple and the overall configuration can be greatly simplified. Further, it is easy to ensure the pressure resistance against the internal oil pressure, and the oil pressure (for example, 3 to 6 kg / cm ² ) of the internal combustion engine can be directly introduced without passing through the pressure reducing device. In addition, since the entire oil passage is constituted by the soft outer tube 6, the vibration resistance is excellent.

[0017]

As is apparent from the above description, according to the oil deterioration detecting device of the present invention, the outer tube made of the soft synthetic resin is deformed flat to form the oil flow path for measurement. As a result, the structure is greatly simplified as compared with the conventional one using a pair of plate-shaped members. In particular, connection and sealing with the inlet and outlet pipes are facilitated, and the reliability and durability are excellent. It will be. Further, the pressure resistance against the internal oil pressure is increased, and the pressure reducing device can be omitted. In addition, it has excellent earthquake resistance.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along the line AA of FIG. 3 showing one embodiment of the present invention;

FIG. 2 is a front view showing a main part of the oil deterioration detection device according to the present invention.

FIG. 3 is a side view of the same.

FIG. 4 is a sectional view taken along the line BB of FIG. 2;

FIG. 5 is a sectional view showing a main part of a conventional oil deterioration detection device.

[Explanation of symbols]

 2 ... oil inlet pipe 3 ... oil outlet pipe 6 ... outer tube 7 ... bracket 8 ... inner tube 9 ... window hole

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuhiro Nogami 5--24-15 Minamidai, Nakano-ku, Tokyo Inside Calsonic Co., Ltd. (72) Inventor Koji Naito 3--17-3 Nishinaminami, Toda City, Saitama Prefecture Toshimitsu Suzuki, Examiner, Kishiishi Product Technology Research Institute, Shikisha Co., Ltd. (56) References JP-A-3-94141 (JP, A) JP-A 53-72566 (JP, U) JP-A 46-29680 (JP, Y1) Special table Sho 62-500738 (JP, A)

Claims (1)

(57) [Claims] 1. An oil deterioration detecting device for interposing oil between a light emitting section and a light receiving section and detecting a degree of oil deterioration from transmittance thereof, wherein an oil axis orthogonal to an optical axis is provided between the light emitting section and the light receiving section. And an outer tube made of a soft synthetic resin having ends connected to an oil inlet pipe and an oil outlet pipe, respectively, and passing light for measurement, facing a predetermined distance. The outer tube is formed in advance in a flat tube shape having parallel wall surfaces, and the parallel surface is inserted in a position intersecting the optical axis of the outer tube in a posture orthogonal to the optical axis, and a window hole is formed at a position on the optical axis. A rigid inner tube having an opening formed therein, and a bracket for clamping and fixing a portion intersecting the optical axis of the outer tube into which the inner tube is inserted from both sides in the optical axis direction. An oil deterioration detection device, comprising: