JPH08178802A - Valve system wear tester by the firing method - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to make it possible to reproducibly set the severity to a fixed target value in a valve operating system wear test apparatus by the firing method. [Structure] In a valve train wear test device by the firing method, a plurality of valve spring retainers of various weights are prepared in the engine, and the valve spring retainers are replaceable. System wear test equipment.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a valve train wear test apparatus in a firing method.

[0002]

2. Description of the Related Art Engine wear systems for engine valve systems include those that use the power of the engine itself to drive the valve system, and those that do not use the power of the engine but have a separate electric motor attached to operate the valve. There are types that drive the system. The former type is called a fired valve operating system. This fired valve system wear test has an advantage of being able to observe and evaluate the effects on wear caused by combustion that cannot be obtained by the motoring valve system wear test. Japan Society of Automotive Engineers JASO M 32
In 8-83, Nissan L18 was specified as a test engine for the wear valve wear test, but in industry, the same L16 is actually used for the same purpose.
Table 1 shows an example of test conditions in this firing test.
As shown in.

[Table 1] Remarks 1. The property of the fuel shall be JIS K 2202 (automobile gasoline) No. 2 equivalent. 2. The oil pan oil temperature is measured with the tip of the oil level gauge. However, it has been found that there are many cases where the target severity cannot be achieved only by these test conditions or there is a case where the severity is not within a certain range because the severity varies from engine valve to engine engine within a certain range.

[0003]

[Object] An object of the present invention is to make it possible to reproducibly set the severity to a constant target value in a valve train type wear test device by the firing method.

[0004]

According to a first aspect of the present invention, a plurality of valve spring retainers of various weights are prepared in an engine in a valve train wear test device by a firing method, and the valve spring retainers are replaceable. The present invention relates to a valve system wear test device by a firing method. A second aspect of the present invention is a valve train wear test apparatus by the firing method, further, a plurality of valve spring retainers in the engine having various cotter hole diameters are prepared, and these are also replaceable together. The present invention relates to a valve train wear test device by the firing method. In the present invention, since the severity is accurately adjusted to the target value and the reproducibility of data is further improved, an oil temperature control means capable of keeping the temperature of the engine oil constant can be provided. The oil temperature control method is preferably a method in which oil is taken out from an oil pan of an engine by a pipe and the oil is returned to the oil pan through a heat exchanger.

The valve spring retainer is, for example, a standard weight of a genuine product, plus 3.5 g, +7.0 g, +
10.0 g, +15.0 g, +20.0 g, -5.0
Various weights such as g, -8.5 g, and -12.0 g are prepared. Then, replace the valve spring retainer with an appropriate weight according to the degree of scuffing of the rocker arm pad. It is understandable that the same severity will occur unless the weight of the valve spring retainer is changed for different engines, but even with one engine, all cylinders have the same severity. Therefore, the severity can be adjusted by the weight of the valve spring retainer for each cylinder. Of course, it is a matter of course for each engine, but it is the greatest feature and merit of this first invention that the severity can be freely adjusted for each cylinder. Curiously, the greater the weight of the valve spring retainer, the higher the severity, and the smaller the weight, the lower the severity. The cotter hole diameter of the valve spring retainer in the valve train is prepared by changing the size of the hole in parallel to the wall surface of the hole of the genuine part. Usually, it is sufficient to prepare 5 to 10 kinds in which the hole diameter is changed by 0.1 mm. Then, replace the retainer with an appropriate cotter hole diameter according to the degree of scuffing of the rocker arm pad. It is unavoidable that the same severity will not occur if the cotter hole diameter of the retainer is changed for different engines, but even with one engine, the same severity will be obtained for each cylinder. However, the severity can be adjusted by changing the cotter hole diameter of the retainer for each cylinder. Of course, the greatest merit of the second invention is that the severity can be freely adjusted for each cylinder, not to mention for each engine. Curiously, the retainer becomes more severe as the cotter hole diameter becomes larger, and becomes smaller as the hole diameter becomes smaller. Generally, the natural frequency of the engine valve system is calculated by the following equation.

[Equation 1] However, fo: Natural frequency of valve system Hz Ko: Equivalent rigidity of valve system kgf / mm me: Equivalent mass of valve system kgf When evaluating the valve operating mechanism of an engine, the ability to respond to engine speed increase and scuffing resistance Performance is one of the important measures. One of the causes of impairing these performances is abnormal motion of the valve train. This is because, for example, as the engine speed increases, the higher harmonic components of the cam valve lift curve approach and overlap with the valve operating system natural frequency, causing natural vibrations, which in turn causes jumping and bouncing. It is a phenomenon that causes abnormal movement. The present inventors
As a result of various studies on the severity of the test apparatus, it was clarified that the relationship between the torsional frequency caused by the drive system and the natural frequency of the valve train is important, and the present invention was completed. When the weight of the valve spring retainer or the like is changed, the me of the above equation 1 changes and the natural frequency of the valve operating system changes. That is, it has been found that when the weight is added to increase the me, the natural frequency of the valve operating system is lowered, abnormal movement of the valve operating system is likely to occur, and the severity of scuffing wear is increased. Further, even if the diameter of the cotter hole of the valve spring retainer is changed, the Ko of the equation 1 is changed and the natural frequency of the valve train is changed.
That is, it was found that when the cotter hole diameter is increased and Ko is decreased, the natural frequency of the valve operating system decreases, abnormal movement of the valve operating system is likely to occur, and the severity of scuffing wear and the like increases.

The temperature control of the engine oil in the valve train wear test has existed for some time even in the conventional test equipment. As its method, (1) a pipe having a large number of holes arranged around the oil pan is used. There are methods of spraying more cooling water, and (2) a method of attaching an oil cooler between the oil filter and the oil filter mounting base, which can be used in the present invention for the time being. In the method, as shown in Table 2, the temperature distribution has irregularities, and the oil temperature control is still incomplete. Therefore,
In the present invention, the heat exchanger system as described above is preferable. For temperature control, an on-off pulse type PI
D (Proportional / Integral / D
It is preferable that it is differential control.
On / off control using a thermostat, which has been widely used in the past, is not recommended because the fluctuations above and below the temperature are too great until the temperature stabilizes.

[0007]

[Table 2]

It is necessary to prepare valve spring retainers of various weights. An example thereof will be described below, but the method of changing the weight is arbitrary and is not limited to the following description. Generally, if the sintered alloy, which is commonly used in gasoline engines, is used, the weight can be adjusted by increasing / decreasing other than the basic structure as shown in FIG. 2A is a perspective view of a conventional retainer used from the back side, and FIG. 2B is a perspective view of the retainer by enlarging a portion unrelated to the basic structure of FIG. It is a perspective view which shows the example which increased weight. Further, as a method that can be easily performed on site, a method of welding or silver brazing to a retainer currently using a steel ring (for example, a plain washer) as shown in FIG. 3 can be used. FIG. 3 (a) is a perspective view of a conventional retainer used from the front side, and FIG. 3 (b) shows that a plain washer is joined to a portion unrelated to the basic structure of (a). It is a perspective view which shows the example which increased the weight of the retainer by. To further reduce the weight, use a material that has a high mechanical strength and a low density, such as ceramics, and make one that has the same shape as the genuine retainer. It is possible to adopt a method such as silver brazing. The normal valve spring retainer is, for example, + 3.5g, + 7.0g, + 10.0g, +1 in addition to standard weight genuine parts.
5.0 g, +20.0 g, -5.0 g, -8.5 g,-
It is preferable to prepare various weights such as 12.0 g.

[0009]

【Example】

(1) Equipment used (see Figure 1; solid arrows in the figure indicate the flow of cooling water)

TABLE 3 Engine Type Nissan L18 or L16 total engine cm ³ 1770 or 1595 cycles Number 4 cylinder number 4 valves arranged OHC maximum torque kgfm / rpm 15.0 / 3600 or 13.5 / 4000

(2) Preparation parts for adjustment Valve spring retainer with changed weight Genuine product, + 3.5g, + 7.0g, + 10.0g, +1
Available in 5.0g, + 20.0g, and -5.0g Valve spring retainer with different cotter hole diameter Genuine product, 0.1mm enlarged, 0.2mm enlarged, 0.3mm
Prepared enlarged

(3) Engine oil Showa Shell Sekiyu KK standard oil NXP230 (hereinafter referred to as REO3
Displayed as) Properties of engine oil

[Table 4] Test item REO3 specific gravity 15/4 ℃ 0.8658 Flash point (COC) 232 Kinematic viscosity mm ² / S @ 40 ℃ 61.95 @ 100 ℃ 10.60 Viscosity index 162 Pour point ℃ -35 0.0 Total acid number mg KOH / g 3.20 Total base number (hydrochloric acid method) mg KOH / g 5.57 Sulfated ash content% wt 0.6 Phosphorus content% wt 0.058 Zinc content% wt 0.066 Calcium content% wt 0.024

(4) Severity adjustment target

[Table 5] Evaluation item Item REO3 rocker arm pad rating ( MR ) 8.3 ± 0.05

(5.1) Severity adjustment result (1.6 liter in-line 4-cylinder OHC engine, oil temperature control by heat exchanger system)

[Table 6] (1) (2) REO 3 REO 3 Retainer Weight Change No. 1 Genuine retainer + 7.0g 2 Genuine retainer Genuine retainer 3 Genuine retainer + 7.0g 4 Genuine retainer + 10.0g 5 Genuine retainer + 7.0g 6 Genuine retainer + 10.0g 7 Genuine retainer + 7. Change to 0g 8 Genuine retainer + Change to 7.0g Engine vibration Horizontal displacement mmp-p 0.11 0.12 Acceleration g 0.26 0.26 Vertical displacement mmp-p 0.18 0.20 Acceleration g 0 .28 0.30 (1) (2) REO 3 REO 3 Valve system wear damage Rocker arm pad MR average value 8.4 8.3 〃 Average wear amount mg 4.7 5.4 Cam nose M. R. Average value 8.4 8.3 〃 Average amount of wear μm 6.9 7.9 Rocker arm pad M.P. R. No. 1 8.4 8.3 2 8.3 8.3 3 8.4 8.3 4 8.5 8.3 5 8.4 8.3 6 8.5 8.3 7.3 7 8.4 8.3 8 8.4 8.3 Note Rocker arm pad or cam nose M. R.
Is a rocker arm pad or cam nose score and is a numerical value indicating what kind of scuffing has occurred and to what extent scuffing may occur in the entire area of the surface where scuffing may occur. R. Were averaged to obtain the average value. In addition, M. R. Details of the evaluation method are JASO
M 328-83.

(5.2) Severity adjustment result (1.6 liter in-line 4-cylinder OHC engine, oil temperature control by heat exchanger system)

[Table 7] (1) (2) REO 3 REO 3 Change of retainer cotter hole diameter No. 1 Genuine retainer Cotta hole diameter expanded by 0.2mm 2 Genuine retainer Genuine retainer 3 Genuine retainer Cotta hole diameter expanded by 0.2mm 4 Genuine retainer Cotta hole diameter expanded by 0.3mm 5 Genuine retainer Cotta hole diameter expanded by 0.2mm 6 Genuine retainer cotter hole diameter expanded 0.3mm 7 Genuine retainer cotter hole diameter expanded 0.2mm 8 Genuine retainer cotter hole diameter expanded 0.2mm Engine vibration lateral displacement mmp-p 0.11 0.11 acceleration g 0 .26 0.27 Longitudinal direction displacement mmp-p 0.18 0.19 Acceleration g 0.28 0.31 (1) (2) REO 3 REO 3 Valve system wear damage Rocker arm pad MR average value 8.4 8.3〃Average wear amount mg 4.7 5.7 Cam nose M. R. Average value 8.4 8.3 〃 Average amount of wear μm 6.9 7.9 Rocker arm pad M.P. R. No. 1 8.4 8.3 2 8.3 8.3 3 8.4 8.3 4 8.5 8.3 5 8.4 8.3 6 8.5 8.2 8.2 7 8.4 8.3 8 8.4 8.4

(5.3) Severity adjustment result (1.6 liter in-line 4-cylinder OHC engine, oil temperature control by heat exchanger system)

[Table 8] (1) (2) REO 3 REO 3 Retainer Cotta Change of hole diameter and weight No. 1 Genuine retainer Cotta hole diameter expanded by 0.2mm 2 Genuine retainer Genuine retainer 3 Genuine retainer Cotta hole diameter expanded by 0.2mm 4 Genuine retainer Cotta hole diameter expanded by 0.3mm 5 Genuine retainer Cotta hole diameter expanded by 0.2mm 6 Genuine retainer cotter hole diameter expanded by 0.2 mm, weight changed to +7.0 g from genuine product 7 Genuine retainer cotter hole diameter expanded by 0.2 mm 8 Genuine retainer cotter hole diameter expanded by 0.2 mm, further weight Changed from genuine product to +3.5 g (1) (2) REO 3 REO 3 engine vibration lateral displacement mmp-p 0.11 0.11 acceleration g 0.26 0.28 longitudinal displacement mmp-p 0.18 0.19 Acceleration g 0.28 0.33 Valve system wear damage Rocker arm pad MR average value 8.4 8.3 〃 Average wear amount mg 4. 7 5.6 Camnose M. R. Average value 8.4 8.3 〃 Average wear amount μm 6.9 8.2 Rocker arm pad M. R. No. 1 8.4 8.3 2 8.3 8.3 3 8.4 8.3 4 8.5 8.3 5 8.4 8.3 6 8.5 8.3 7.3 7 8.4 8.3 8 8.4 8.3

[0016]

[Effect] According to the present invention, the severity of the valve operating system wear test by the firing method can be set easily and accurately, so that the variation of the data in the test is greatly reduced. Further, according to the present invention, it is also a great merit that the severity can be adjusted for each valve in one engine.

[Brief description of drawings]

FIG. 1 is a model diagram showing a specific example of the present invention.

FIG. 2 (a) is a perspective view of an ordinary retainer used in the past as viewed from the back side, and FIG. 2 (b) is a perspective view showing the weight of the retainer, which is not related to the basic structure of FIG. It is the perspective view seen from the back side of the enlarged retainer.

FIG. 3 (a) is a perspective view of an ordinary retainer which has been conventionally used, viewed from the front side, and FIG. 3 (b) is a view showing a plain washer being joined to a portion unrelated to the basic structure of (a). It is the perspective view seen from the front side of the retainer which increased weight.

[Explanation of symbols]

 1 Engine (Valve system exists in the upper part) 2 Water temperature control heat exchanger 3 External cooling water system 4 Pressurization cap 5 Vent 6 Water pump 7 Vibrometer 8 Oil temperature control device 9 Oil pump 10 Oil temperature control heat exchanger 11 Accelerometer 12 Throttle Actuator 13 Exhaust Gas Analyzer 14 Control Recorder

Claims (4)

[Claims] 1. A valve system wear test apparatus by the firing method, wherein a plurality of valve spring retainers of various weights are prepared in the engine, and the valve spring retainers are replaceable. Valve system wear test equipment. 2. Further, a plurality of valve spring retainers in the engine having various cotter hole diameters are prepared,
The valve operating system wear test apparatus according to claim 1, which is also replaceable. 3. A valve operating system wear test apparatus according to claim 1 or 2, further comprising temperature control means for maintaining a constant oil temperature in the engine. 4. The temperature control means according to claim 3, wherein oil is taken out from the oil pan by a pipe and is circulated through a heat exchanger to be returned to the oil pan to correct the temperature to a predetermined temperature. A valve train wear tester using the firing method.