JPH055211Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a piston engine cylinder lubrication evaluation device for evaluating the lubrication state of cylinders of various internal combustion engines.

[Prior art] For example, in a diesel engine, the temperature is measured using a thermocouple embedded in the cylinder liner, and the lubrication state of the sliding surfaces is determined from changes in the liner temperature, and the operating conditions are controlled and the amount of lubricant supplied. This control prevents serious accidents and breakdowns.

However, the response of liner temperature is generally poor;
Because it changes due to changes in engine load, etc., it is not suitable for determining the quality of the lubrication between the inner surface of the cylinder liner and the piston ring, or the amount of wear. A cylinder lubrication evaluation device using

FIG. 3 is a diagram for explaining the system configuration of the cylinder lubrication evaluation device. In the figure, 11 is a piston body, 12 is a piston ring, 13 is a cylinder liner, 14 is a cylinder cover, 15 is an exhaust valve, and 16 is a cylinder liner.
is the fuel valve. That is, the cylinder liner 13
An ultrasonic wave transmitter 17 is attached to the outer peripheral surface of the cylinder liner, and a synchronizer 18 for pulse generation timing control controls the timing appropriately based on the crank angle signal to send ultrasonic waves from an ultrasonic pulse generation/transmission circuit 19 to the cylinder liner. Waves are transmitted from the ultrasonic wave transmitter 17 toward the inner surface (sliding surface) of the waveguide 13. On the other hand, 20 indicates an ultrasonic wave receiver, and a signal received by the ultrasonic wave receiver 20 is amplified by an ultrasonic receiver circuit 21, and an ultrasonic signal waveform is displayed on a display section 22. FIG. 4 schematically shows the reflection and transmission of this ultrasonic wave on the sliding surface, as well as the reflection on the back surface of the piston ring. Here, when the synchronizer 18 from the ultrasonic wave transmitter 17 synchronizes the timing with the passing of the piston ring and injects the ultrasonic wave in a pulse form, the ultrasonic wave passes through the cylinder liner 13 and hits the sliding piston ring that is just passing through. reaching the surface.

At this time, if there is an oil film 23 between the cylinder liner 13 and the piston ring 12, part of the ultrasonic wave will be reflected from the sliding surface of the cylinder liner 13, and another part will pass through the oil film 23 and pass through the piston ring sliding surface. It is reflected from the moving surface and the back surface, passes through the oil film 23 again, and returns to the ultrasonic wave receiver 20. On the other hand, if there is no oil film 23 between the cylinder liner 13 and the piston ring 12, the ultrasonic waves are only reflected from the sliding surface of the cylinder liner 13 and the piston ring 12
Therefore, the ultrasonic wave receiver 20 receives only the reflected wave from the cylinder liner sliding surface as a reflected wave.

Therefore, according to this method, it is possible to evaluate whether there is a lubricating oil film or not, and to reduce or optimize the amount of lubricating oil, based on the pattern of reflected ultrasonic waves and the height of the reflected waves. It is.

[Problems to be solved by the invention] As described above, it is possible to evaluate the lubrication state between the inner surface of the cylinder liner 13 and the piston ring 12 by transmitting and receiving ultrasonic waves. When the transmitting/receiving elements 17 and 20 are attached to the outer peripheral surface of the cylinder liner 13, the following problems occur.

In other words, cast iron is generally used as the cylinder liner material due to its wear resistance and lubricity, and in the case of large engines, the thickness of the cylinder liner is several tens of mm or more.
It can reach several hundred millimeters. The crystalline structure of cast iron contains many minute reflection sources, and has very poor ultrasonic transmission, which becomes more pronounced as the thickness of cast iron increases. For this reason, the detection accuracy of ultrasonic waves is significantly impaired. A comparison of this situation between normal defect-free steel materials (for example, SS materials and SC materials) and cast iron will be explained with reference to FIGS. 5 and 6.

That is, in FIG. 5, the cylinder liner 1
3 is made of steel material (for example, S45C), and in this case, in response to the transmitted wave S1 of the ultrasonic wave transmitter 17, reflected waves S2 from the sliding surface of the cylinder liner and reflected waves S3 from the back surface of the piston ring are generated. It returns to the ultrasonic wave receiver 20. On the other hand, in FIG. 6, the cylinder liner 13 is formed using cast iron (for example, F25), and in this case, the ultrasonic wave transmitter 17
With respect to the transmitted wave S1, no reflected waves or the like are returned to the ultrasonic wave receiver 20 from the cylinder liner sliding surface.

In this way, when the ultrasonic transducers 17 and 20 are attached to the outer peripheral surface of the thick cast iron cylinder liner 13, it becomes difficult to evaluate the lubrication state between the inner surface of the cylinder liner 13 and the piston ring 12. .

The present invention was developed in view of the above points, and the purpose is to provide a cylinder lubrication evaluation device for a piston engine that improves ultrasonic detection accuracy and enables highly reliable evaluation of the lubrication state. .

[Means for solving the problem] In other words, in the cylinder lubrication evaluation device for a piston engine according to the present invention, in order to improve ultrasonic detection accuracy, the sliding surface side of the cylinder liner is made of cast iron from the viewpoint of wear resistance and lubricity. However, a notch is formed in the ultrasonic transducer mounting part so that the wall thickness of the cast iron part is thin (for example, approximately 40 mm or less), and this notch, that is, the connection between the ultrasonic transducer mounting surface and the cast iron. In between, a metal material with good ultrasonic transparency (for example, SC material or
Steel materials such as SS materials) or fluids (e.g.
It is characterized by having a layer of glycerin, water glass, hydraulic oil, etc.).

[Function] In the above configuration, since the cast iron portion has a thin wall thickness, the ultrasonic transmittance is less deteriorated by minute reflection sources inherent in the crystal structure, and the propagation characteristics are significantly improved. Additionally, a layer with good ultrasonic transparency is provided between the cast iron and the ultrasonic transducer, so even if the distance between the cylinder liner sliding surface and the ultrasonic transducer increases, the propagation characteristics will not be impaired. Never.

As described above, since the detection accuracy of ultrasonic waves is improved, it becomes possible to evaluate the lubrication state of the sliding surface. Furthermore, since the sliding surface of the cylinder liner is made of cast iron, wear resistance and lubricity are ensured as in the past.

[Embodiment] A cylinder lubrication evaluation device for a piston engine according to an embodiment of the present invention will be described below with reference to the drawings. The basic configuration of the cylinder lubrication evaluation device in the example is the same as the conventional one, and its explanation will be omitted. I will only explain.

That is, FIG. 1 is a side view of the vicinity of the cylinder liner according to one embodiment, and in the figure, 12, 13,
17, 20, and 23 are a piston ring, a cylinder liner ultrasonic wave transmitter, an ultrasonic wave receiver, and an oil film as in the conventional case.

The cylinder liner 13 is made of cast iron in terms of wear resistance and lubricity. A notch 31 is formed on the side of the cylinder liner 13 where the ultrasonic transmitter/receiver is attached, that is, where the ultrasonic wave transmitter 17 and the ultrasonic receiver 20 are attached, so that the thickness of the cast iron is reduced. In this notch 31, an insertion member 32 made of a steel material such as S45C and having high ultrasonic transparency is fixed at its flange 32a to the outer peripheral surface of the cylinder liner 13 with bolts 33a and 33b. It is inserted as shown.

In this case, if there is a gap between the notch 31 and the insertion member 32, for example, glycerin,
A φ ring 35 is provided to seal a layer 34 of a fluid with good ultrasonic propagation properties, such as water glass or hydraulic oil.

In such a configuration, the cylinder liner 1
Since the thickness of the cast iron portion in the ultrasonic transmitter/receiver mounting portion of No. 3 is thin, there is little deterioration of ultrasonic transmittance due to minute reflection sources inherent in the crystal structure, and the propagation characteristics are significantly improved. Furthermore, since an insertion member 32 having high ultrasonic transparency is inserted between the cast iron and the ultrasonic transducer, that is, in the notch 31, the cylinder liner is inserted through this insertion member 32. Even if the distance between the ultrasonic transducers 17 and 20 attached to the outer peripheral surface of the cylinder liner 13 and the sliding surface of the cylinder liner becomes longer, the propagation characteristics will not be impaired. Therefore, the ultrasonic testing properties are improved,
It becomes possible to evaluate the lubrication state with high reliability.

In addition, in the embodiment shown in FIG.
1, an insertion member 3 having a property of high ultrasonic transparency;
For example, as shown in FIG. 2, a layer 34 of a fluid having high ultrasonic permeability, such as glycerin, water glass, hydraulic oil, etc., may be inserted into the notch 31. , the flange 32a and the φ ring 35 may be used for sealing, and even in this case, the same effects as in the above embodiment can be obtained.

[Effects of the invention] As described above, according to the invention, a notch is formed on the side where the ultrasonic transducer is attached to the cylinder liner, and the insertion member has a characteristic of high ultrasonic transparency in this notch. Alternatively, by inserting a fluid layer and attaching this insertion member or the above-mentioned ultrasonic transducer with the fluid layer interposed, the ultrasonic inspection accuracy is improved.
It becomes possible to evaluate the lubrication state with high reliability.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of the vicinity of a cylinder liner according to an embodiment of the present invention, FIG. 2 is a side sectional view of the vicinity of a cylinder liner according to another embodiment of the present invention, and FIG.
The figure is a diagram for explaining the system configuration of a conventional cylinder lubrication evaluation device, Figure 4 is a diagram schematically showing the reflection and passage of ultrasonic waves in the conventional system, and Figures 5 and 6 are diagrams showing the cylinder liner. FIG. 3 is a diagram for explaining the difference in ultrasonic transmittance between steel materials and cast iron materials. 12... Piston ring, 13... Cylinder liner, 17... Ultrasonic wave transmitter, 20... Ultrasonic wave receiver, 23... Oil film, 31... Notch, 32
...insertion member, 32a...flange, 33a, 3
3b...Bolt, 34...Fluid layer, 35...φ
ring.

Claims (1)

[Scope of utility model registration request] In a cylinder lubrication evaluation device for a piston engine that attaches an ultrasonic transducer to the outer peripheral surface of a cylinder liner and evaluates the lubrication state between a piston ring and the inner surface of the cylinder liner, an ultrasonic transducer is formed on the side of the cylinder liner on which the ultrasonic transducer is attached. and an insertion member or fluid layer inserted into the cutout having a characteristic of high ultrasonic transparency, and the ultrasonic transducer is attached via the insertion member or fluid layer. A piston engine cylinder lubrication evaluation device characterized by: