JPH035878Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The disclosed technology belongs to the structural technology field of a measurement engine for measuring piston friction force against a cylinder liner of an automobile engine.

Therefore, this invention is a test engine for measuring the frictional force of the piston against the cylinder liner during explosive combustion of an engine installed in a car. This invention relates to a piston friction force measurement engine in which a cylinder liner is installed with a plurality of friction sensors such as piezo type bags interposed between a cylinder mounting base and the cylinder liner via bolts or the like, In particular, the invention relates to a piston friction force measuring engine in which the cylinder liner mounting base outside the cylinder liner and the cylinder head mounting base provided on the upper part of the cylinder liner are separately installed and separated from each other and mounted on the crankcase. It is.

<Prior Art> As is well known, the internal combustion engine installed in a car generates a lot of vibration when the engine is running.Recently, technologies have been developed to suppress and absorb the vibrations of the car to ensure quiet driving.
Countermeasures are being taken all the time to improve riding comfort, and for this purpose, many basic experiments and theoretical analyzes of data based on these basic experiments are being studied.

Therefore, in an automobile internal combustion engine, the piston slides relative to the cylinder liner,
The frictional force of the piston against the cylinder liner plays a major role in contributing to vibration, and accounts for a large proportion of engine vibration.

Since the frictional force between the cylinder liner and the piston during engine explosion and combustion is large, from the viewpoint of sealing the piston against the cylinder liner, it is not possible to reduce the frictional force to zero, but it is possible to reduce the frictional force as much as possible. Many studies are being conducted to reduce this as much as possible.

Therefore, as mentioned above, in order to conduct experiments that will serve as basic data for this research, for example,
Piston friction force measurement engines such as those disclosed in Japanese Patent No. 22921 have been developed and used.

The piston friction force measurement engine 1 that has been used so far has a cylinder liner 3 and a cylinder head 4 that are integrally fixed to the crankcase 2, as illustrated in FIGS. 3 and 4, for example. A piston 7 is provided at the upper end of a cone rod 6 connected to a crankshaft (not shown) inside the bore 5 formed by the cylinder liner 3, so that the piston 7 slides up and down. Bolts 10, 10 are attached to the cylinder head mounting base 8 and the cylinder liner mounting base 9 on the outside thereof.
A predetermined number of friction sensors 11, 11, etc. capable of measuring strain using a well-known piezoelectric current of a three-way force sensor are interposed and fixed, and the detected current is input to a predetermined electrical measuring device (not shown). Thus, the frictional force of the piston 7 against the cylinder liner 3 is electrically measured.

The valve train for the intake valve 12 and the exhaust valve 13 is provided with push rods 14 and 15 extending upward from the bottom to the top.

<Problems to be solved by the invention> By the way, as mentioned above, the problem of research on eliminating vibration systems in automobiles is a new problem in recent years, and therefore basic experiment and test data for analysis research is necessary. is extremely important, and for this reason, the piston friction force measurement by the piston friction force measurement engine 1 described above is carried out quite frequently, and it is necessary.

As shown in Figures 3 and 4, since the piston friction force measuring engine 1 is used for experiments and tests, the structure is simple, there is no water jacket for cooling, and there is no cylinder. The head 4 is integrally connected to the crankcase 2 via a cylinder head mounting base 8 in the vertical direction.

Therefore, during the engine's explosion stroke, an explosion pressure of 2 to 3 tons is applied to the cylinder head 4 as an explosion reaction force, and as a result, the cylinder liner 3
is connected to the friction sensor 11 and the cylinder head mounting base 8 via bolts 10, 10, . Excitation caused by the above explosion impact is generated.

Therefore, the vibration caused by the excitation is superimposed on the friction force signal detected by the friction sensor 11 and becomes noise, and the time interval of the excitation becomes short, especially in the high engine rotation range, and approaches the natural frequency of the vibration system. This has the disadvantage that the amplitude of the vibration increases, making it difficult to obtain measurement data as intended.

Furthermore, as shown in the figure, since the valve operating system for the intake valve 12 and exhaust valve 13 is operated via push rods 14 and 15 that extend upward from the bottom, the cylinder head may interfere with the push rods 14 and 14. There is also the disadvantage that the size of the mounting base 8 and the cylinder liner mounting base 9 cannot be increased, which makes it difficult to securely support the cylinder liner 3, that is, to securely mount the friction sensor 11.
There was also a problem in that the cylinder head mounting base 8 could not securely fix the cylinder head 4 and suppress vibrations.

Further, due to such restrictions, the width of the cylinder liner mounting base 9 cannot be made large, so when the friction sensor 11 is mounted on the cylinder liner 3, the cylinder liner 3 is likely to be distorted due to the mounting, resulting in insufficient strength. Although very strict machining accuracy is required for the cylinder liner 3, there is the disadvantage that this cannot be satisfied.
Furthermore, as shown in Fig. 3, the cylinder liner 3
Because the sum of the lengths in the width direction of the friction sensor 11 and the length of the cylinder head mounting base 8 must match exactly, extremely strict machining accuracy is required.
The manufacturing cost was extremely high, and accuracy control before and after testing was extremely complicated.

As described above, the friction sensor 11
In order to make the measurement accuracy accurate, it is necessary to apply sufficient initial tightening force to the friction sensor 11. However, as mentioned above, when high size accuracy is required, each friction sensor 11 There was a negative point that there was a possibility that the tightening force for one of the parts would be insufficient.

The purpose of this invention is to provide extremely valuable data for analysis and investigation of the vibration system of automobile engines based on the above-mentioned conventional technology. As a technical issue to be solved, it is possible to realize the static installation conditions of the cylinder liner during engine explosion and combustion even during operation, so that only the vibrations during the explosion and combustion are input to the friction sensor, so that reliable data can be obtained. It is an object of the present invention to provide an excellent piston friction force measurement engine that is useful in the field of vibration technology application in the automobile industry.

<Means/effects for solving the problem> In accordance with the above-mentioned purpose, the structure of this invention, which is summarized in the scope of the above-mentioned utility model registration claim, is to solve the above-mentioned problem by improving the cylinder liner of the piston friction force measurement engine. The cylinder liner mounting base for the cylinder liner and the cylinder head mounting base for the cylinder head are divided in the circumferential direction and integrally fixed to a highly rigid crankcase with bolts, etc., and the cylinder is mounted during the explosion stroke applied to the engine during the test. The excitation effect on the engine's vibration system due to the impact reaction force on the head is reduced, noise is not mixed into the detected friction force signal for the friction sensor, and the friction sensor is mounted on the cylinder liner using the above-mentioned cylinder head mounting base. The static mounting of the friction sensor to the cylinder liner is ensured by using a highly rigid cylinder liner mounting base that is separately attached to the crankcase and with a sufficiently large initial tightening force for mounting. Therefore, it is possible to more accurately detect the frictional force of the piston against the cylinder liner in the test, and it is possible to ensure not only manufacturing but also maintenance, inspection and quality control, and therefore obtain the above data more accurately. It is a technical measure that has made it possible to do this.

<Embodiment - Configuration> Next, one embodiment of this invention will be described as follows based on FIGS. 1 and 2. Furthermore, 3rd and 4th
Components that are the same as those in the drawings will be described using the same reference numerals.

1' is a piston friction force measurement engine that forms the gist of this invention, and as in the conventional case, the cylinder liner 3 is connected to the crankcase 2 by an O-ring 16.
The cylinder head 4 is integrally mounted and fixed through an O-ring case 17 having an O-ring 16, and the bore 5 formed by the cylinder head 4 is connected to the crankshaft via a cone rod 6. The piston 7 is in sliding contact so as to slide up and down in the same manner as in the conventional configuration.

Accordingly, in this invention, as shown in FIG.
When fixing through the friction sensor 1, the friction sensor 11 is stably and firmly attached, and
In order to prevent the cylinder liner 3 from being deformed or distorted due to the strong mounting, which would cause inaccurate data on the piston friction force against the cylinder liner 3, as described above, the cylinder head 4 is In order to suppress the excitation of the vibration system due to the explosion shock reaction force during the engine explosion stroke, the cylinder liner mounting base 9' and the cylinder head mounting base 8' are alternately installed around the cylinder liner 3, as shown in Fig. 2. They are separated from each other so as to face each other with a phase change of 90 degrees, and are integrally fixed to the crankcase 2 via bolts 10, 10, . . . to increase rigidity.

As will be described later, in this invention, since an overhead cam system is used for the valve train, there is no interference with the cylinder liner mounting base 9'. The width of the cylinder liner mounting base 9' is made sufficiently large, and the rigidity is enhanced due to its large size.

As shown in FIG. 2, the friction sensor 11 is directly interposed between the cylinder liner 3 and the cylinder liner mounting base 9'.
Therefore, the initial tightening force against the cylinder liner 3 is sufficiently large.

In addition, since the cylinder head mounting base 8' for the cylinder head 4 is provided separately from the cylinder liner mounting base 9' and is designed to support only the cylinder head 4, the explosion impact reaction force due to the engine's explosion stroke is reduced. is absorbed by the extremely rigid crankcase 2, and therefore is not transmitted to the cylinder liner 3 via the cylinder liner mounting base 9', that is, the friction sensor 11, and as a result,
The friction sensor 11 is configured to be able to detect only the frictional force of the piston 7 against the cylinder liner 3 due to the explosive stroke.

Incidentally, the friction sensor 3 is a three-way force sensor similar to the conventional embodiment, and is connected to an electrical measuring device (not shown), and is connected to the cylinder liner mounting base 9' and the cylinder liner 3 via bolts 10, 10...
It is firmly and stably attached between the

In this invention, in order to make the cylinder liner mounting base 9' a large block, the first cylinder liner mounting base 9' is installed on the side of the cylinder liner 3 so as not to interfere with the cylinder liner mounting base 9'. As shown in the figure, an overhead cam system is adopted in which cams 18, 18 directly contact rocker arms 17 for intake valves 12 and exhaust valves 13.

In addition, as shown in Fig. 2, the pulley 1 for driving the cam
9 is fixed to the crank shift 20.

<Embodiment - Effect> In the above-described configuration, when the piston friction force measurement engine 1' is operated normally to detect the friction force of the piston 7 against the cylinder liner 3, as described above, there are two ~
An impact force is applied as a reaction force to the 3 tons of explosive force,
An attempt is made to excite a mass-spring vibration system in which the cylinder liner 3 is the mass and the friction sensor 11 is the spring, but as described above, in the configuration of this invention, the cylinder head 4 is attached to the crankcase 2. Since the connection is made only through the base 8', the vibration is absorbed by the highly rigid crankcase 2, and the excitation vibration is transmitted to the friction sensor 11 via the cylinder liner mounting base 9'. Therefore, only the frictional vibration of the piston 7 against the cylinder liner 3 is detected as an input to the friction sensor 11, and the vibration excited by the cylinder head 4 is not detected as an input. In this case, only the frictional force of the piston 7 against the cylinder liner 3 is accurately detected.

In this case, the detection accuracy is extremely accurate because the bolts 10 are firmly tightened and attached to the cylinder liner 3 by the initial tightening force without loosening via the cylinder liner mounting base 9'.

It goes without saying that the embodiment of this invention is not limited to the above-mentioned embodiments; for example, cushion rubber or the like may be interposed between the cylinder head mounting base and the cylinder liner mounting base, or various other embodiments may be adopted. .

<Effects of the invention> As described above, this invention basically provides a piston friction force measurement engine for obtaining important basic data for improving the fuel efficiency of automobile engines and developing technologies for quiet driving by absorbing vibrations. In this method, the cylinder head is connected to the crankcase through a cylinder head mounting base that is separate from the cylinder liner mounting base for the cylinder liner.
In the test operation, the impact force due to the explosion reaction force during the explosion process was large, and even if it acted on the cylinder head, the reaction force was absorbed by the rigid crankcase via the cylinder head mounting base, and as a result, the cylinder liner It is not transmitted to the cylinder liner via the mounting base, i.e., the friction sensor, and therefore the friction sensor produces an excitation in the mass-spring vibration system of the cylinder liner and friction sensor due to the impact reaction force. As a result, the friction sensor is able to detect only the frictional force of the piston against the cylinder liner, which has the advantage that accurate data on the piston frictional force can be obtained as expected. As a result, the analysis of basic experimental data has an excellent effect of greatly contributing to research and design of weight reduction and vibration absorption of in-vehicle engines.

Furthermore, since the cylinder head mounting base and cylinder liner mounting base are spaced apart from each other, there is no need to form the joint length of the cylinder liner and friction sensor to be exactly equal to the width of the cylinder head mounting base. Therefore, the individual manufacturing precision of the cylinder liner mount and the cylinder head mount is not required to be very precise, and therefore, it is easy to mold, which has the advantage that it can be done at a correspondingly low cost.

Moreover, this increases the degree of freedom in the size of the cylinder liner mounting base, and together with this, an excellent effect is achieved in that the detection accuracy of the friction sensor can be further increased.

Furthermore, since they can be freely assembled during maintenance and inspection, there is no need to strictly require assembly accuracy.

[Brief explanation of the drawing]

Figures 1 and 2 are explanatory diagrams of an embodiment of this invention. Figure 1 is a longitudinal sectional view of one embodiment, Figure 2 is a horizontal sectional view of the same, and Figure 3 is a longitudinal sectional view of the embodiment. ,
FIG. 4 is a longitudinal sectional view of a piston friction force measuring engine based on the prior art. 5...Bore, 7...Piston, 3...Cylinder liner, 9'...Cylinder liner mounting base, 10...
...Friction sensor, 1'... Piston friction force measurement engine, 4... Cylinder head, 8'...
Cylinder head mounting base, 2... crankcase.

Claims (1)

[Scope of utility model registration request] A cylinder head support stand installed above the cylinder liner in a piston friction force measurement engine in which a plurality of friction sensors are interposed between a cylinder liner containing a piston that slides in a bore and a cylinder liner mounting stand. A piston friction force measuring engine characterized in that a cylinder liner mounting base and a cylinder liner mounting base via the friction sensor of the cylinder liner are mounted on a crankcase at a distance from each other.