JP2797270B2 - Valve train wear test equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art In order to improve the engine in accordance with various demands such as increasing the speed and output of the engine, reducing exhaust gas, eliminating the need for gasoline, improving fuel efficiency, and extending the oil change distance, and changing the operating conditions, In recent years, interest in valve train wear has been increasing. In Japan, several major automobile companies first established their own testing methods for valve train wear for evaluating lubricating oil and materials. Unify test methods, JASO
Standards have been established. In recent years, research and development on the valve oil wear prevention performance of engine oil has been advanced mainly by petroleum companies, and the Petroleum Institute of Japan has conducted rating symposiums and workshops on valve gear wear to make efforts to match the evaluation standards of each testing organization. I've been. When a wear test is performed on a table, a method of actually performing a firing operation using fuel or a method of driving by a motor can be considered. Compared to the former, the latter is a much better method in terms of equipment simplification, cost, handling, and repeatability. The frequency of performing the valve train wear test by the motoring method tends to increase year by year.
However, as the number of times this test was performed and the number of test devices increased, it became clear that there were variations in the data due to unification of the evaluation standards and the test device itself beyond the mastery. For example, one of the representative motoring engine tests, JASO standard Toyota 3A and old standard Toyota 2
The results of testing each standard oil with a 0R engine were published by JASO, but reports show that even only a few testing laboratories have large variability in wear damage results. After that, the contents announced by the ISO National Committee for compliance with international standards were the same, and the reproducibility also varied greatly. It has also been found that when the repeatability test is further performed about 10 to 15 times, there is a considerable difference between the first and last results. Therefore, the present inventors have conducted various studies on the causes of data variation, and as a result, it was found that the reproducibility of the severity, which is a load factor applied to the test specimen, was poor and the same load could not be applied. I found out.

[0003]

An object of the present invention is to provide a valve train wear test apparatus which can easily and easily adjust the degree of severity, which is a load factor applied to a test piece, in a valve train wear test of an engine. On the point.

[0004]

[Constitution] When evaluating the wear resistance of a valve train, if the severity of the test apparatus is out of the appropriate range, it must be adjusted to fall within the appropriate range. The inventors of the present invention have conducted various studies on what caused the variation in the degree of severity to ensure that the degree of severity to be set in the test apparatus is reproducible within a certain range. Elucidating that the strength of low frequency torsional vibration has a great effect on the wear and damage of the valve train, and forcibly changing the appropriate conditions of the parts involved in the vibration and self-excitation / damping effects As a result, it was discovered that the severity could be freely adjusted within a predetermined range with good reproducibility, and the present invention was completed. That is, the present invention relates to a valve train wear test apparatus including an engine valve train, a motor for forcibly driving the engine valve train, and a transmission member for transmitting rotation of the motor to the valve train, The present invention relates to a valve train wear test apparatus provided with means for controlling the frequency of a member. According to the present invention, it is possible to accurately determine what kind of material is appropriate for the rocker arm pad and the cam nose, depending on the wear of the valve train, for example, the wear of the rocker arm pad and the cam nose. In addition, it is possible to know which engine oil or lubricating oil is better by changing the amount of wear caused by changing the engine oil or lubricating oil. The transmission member is a belt, a chain, or a rope, and transmits the rotation of the motor to a valve train of an engine via a pulley, a sprocket, and a sheave. Note that an elastic material is more preferable as the transmission member in controlling the frequency. As the belt, a V belt, a toothed belt, a ribbed belt, or the like can be used. Specifically, the frequency can be controlled by adjusting the tension of the belt (chain), the thickness of the belt (chain), the material of the belt (chain), the length of the belt (chain), and the like. it can. As a specific method of changing the frequency with the same transmission member, the span and tension of the belt can be changed by relatively shifting the position of the valve train and the position of the motor in FIG. More specifically,
By fine-tuning the height of the motor, the belt tension and span can be changed to adjust the severity.

It is known that the following relational expression is already established for belt vibration (Himeji Institute of Technology, Research Report No. 21, October 1968, Kazuo Sugawara, Kumi Sekiguchi:
V-belt vibration). According to it

(Equation 1)

(Equation 2) Therefore, the free frequency is increased by increasing the belt tension. Also, when the belt is driven,
The free frequency has the property of decreasing as the speed increases. FIG. 2 shows a model diagram of the relationship between the natural frequency of the engine valve system and the belt system and the free frequency of the belt based on their respective properties. FIG.
As shown in the figure, when the test device is driven at a certain speed,
When the frequency of the engine system and the belt system or an integral multiple thereof and the free frequency of the belt approach and overlap, the vibration becomes violent and finally causes resonance. Generally, the amplitude is then dangerously large, causing damage to the mechanical elements, excessive fatigue and unwanted noise. At this time, the severity given to the valve train is maximized, which is the condition under which scuffing wear, which is surface damage of the valve train, occurs most rapidly.

Therefore, in the present invention, the frequency of a transmission member such as a belt, a chain, or a rope is made to coincide with or approach the natural frequency of the valve train so that the two sometimes resonate or are in a state close to that. By making, the severity required for the test can be arbitrarily applied to the test specimen. In particular, one of the present invention
In an embodiment, the belt tension is adjusted by adjusting the distance between the pulleys over which the belt is stretched, and the free frequency f of the belt is controlled. The condition for causing the natural frequency of the resonance to sometimes resonate or the condition for causing the resonance to slightly resonate is freely created. If the frequency of the belt is displayed as the amount of deflection of the belt and the severity is displayed as rocker pad scuffing DR, the relationship between the amount of deflection and the severity is as shown in FIG. The numerical values in FIG. 3 are numerical values obtained when an experiment is performed under specific conditions, but FIG. 3 merely shows the relative relationship between the severity and the amount of deflection.

The present invention will be described with reference to the drawings. FIG.
Shows one specific example of the present invention. The three V-belts 4 are suspended between a pulley 3 connected to the crankshaft 2 of the engine 1 and a pulley 5 connected to the rotating shaft of the motor 6. For example, by changing the height position of the motor 6, The distance between V and 5 is changed to adjust the tension of the V-belt. The belt tension can be determined with a tension gauge. Vibrations at various tensions were measured by a vibrometer 7 set on the engine and the motor, respectively. In the test apparatus, the pulley 3 was attached to the crankshaft 2 protruding to the rear side of the engine and connected to the pulley 5 on the motor 6 side. A pulley can be attached and connected to the pulley on the motor side (see FIG. 5). In FIGS. 1 and 5, the pulley and the V-belt are positioned vertically, but the pulley and the V-belt may be used horizontally. The test device of FIG. 1 was provided with a device 8 capable of controlling the temperature of the engine oil to be constant. 9 is a pump and 10 is a heat exchanger. 11 and 12 are accelerometers. An inverter 13 finely adjusts the number of revolutions with high accuracy. Reference numeral 14 denotes a control recorder, which controls the room temperature, oil temperature, oil pressure,
Display and record the accumulated time and number of rotations. Since the engine 1 of FIG. 1 uses the entire engine, an oil pan or the like is attached to a lower portion of the engine 1. However, if the temperature of the engine oil is properly controlled, the cylinder block and the oil pan can be omitted. If the cylinder block and the oil pan are omitted and the whole is reduced in size, it can be a desk type.

[0008]

EXAMPLES Example 1 (1) Apparatus used (see FIG. 1)

(A) Engine (based on JASO standard M328-91) Model Toyota 3A Total displacement cm ³ 1452 Number of cycles 4 Number of cylinders 4 Valve arrangement OHC rocker arm type 1-3-4-2 Maximum torque kgfm / rpm 12 2.0 / 3600 Remarks Remove the piston, connecting rod and flywheel from the engine. (B) Drive (i) Motor Model Toshiba three-phase induction motor or equivalent Output / voltage kw / v 3.7 / 200 rpm rpm 1440 (ii ) Power transmission belt Model Narrow V-belt, Wrapped type, Samsung Maxter wedge belt No. (belt length mm) 3V-425 (1080) Number 3 (iii) Bushing pulley Model Flat type Name (Large) Q1-30 (Small) ) HF-3 (2) Engine oil Toyota Motor Corporation Pure Oil Brand name Castle Lean Super 10W / 30 (as REO1) and Showa Shell Sekiyu Co., Ltd. Sample Oil No. TY-P001 (as REO2)

(2) Properties of engine oil

TABLE 2 test item REO1 REO2 specific gravity 15/4 ℃ 0.8729 0.8729 Flash point (COC) ℃ 230 232 kinematic viscosity ^{mm 2 / S @ 40 ℃ 62.9} 71.87 @ 100 ℃ 9.90 10.59 Viscosity index 142 134 Pour point ℃ -30.0-40.0 Total acid value mgKOH / g 1.20 1.40 Total base number (hydrochloric acid method) mg KOH / g 1.58 5.00 Sulfated ash% wt 0.38 0.57 Phosphorus% wt 0.054 0.057 Zinc% wt 0.062 0.061 Calcium% wt 0.043 0.130 Barium% wt 0.079 −

(3) Severity adjustment target

[Table 3]Evaluation item REO1 REO2  Rocker arm pad rating (D.R.) ≤5 55 ± 5 Note that the adjustment range of the severity is not limited to this.
For example, in the case of REO2, the range of 40 to 70 is set according to the present invention.
Can be easily covered. The lock in this specification
Car arm pad rating (DR) is scuffing
What percentage of the total surface (pad) area that can occur
Numeric value indicating whether scuffing occurred in the
You. And this is one way of expressing severity.

(4) Results of Severity Adjustment * 1 to * 3 in the following Tables 4, 5 and 8 are as follows. * 1: The deflection amount is measured by pressing the center of the span with a tension gauge as shown in FIG. 4 and displaying the dent width of the belt in mm when the load is 10 kgf. The term "engine side" refers to the engine side because three V-belts are used in parallel. "Intermediate" refers to the middle of the three V-belts. “Motor side” refers to the motor side of the three V-belts. * 2: The horizontal and perpendicular directions to the camshaft axis of the engine are indicated as horizontal, the up-down direction is indicated as vertical, and the camshaft axis is indicated as front-back. For displacement, the distance from peak to peak was expressed in mm. * 3: Cam nose DR is the percentage of the cam nose friction contact part
Indicates whether or not scuffing has occurred, which is also one expression of the severity.

[Table 4] (1) (2) (3) (4)REO1 REO2 REO2 REO2  Belt deflection (＠ 10kgf) mm * 1 Engine side V-belt 20 20 17 18 Middle V-belt 20 20 17 18 Motor side V-belt 20 20 17 18 Engine vibration * 2 Lateral displacement mmp-p 0.07 0.06 0.06 0.06 acceleration g 0.23 0.28 0.18 0.19 longitudinal displacement mmp-p 0.12 0.11 0.21 0.16 acceleration g 0.40 0.46 0.24 0.27 longitudinal displacement mmp-p 0.07 0.07 0.05 0.12 acceleration g 0.35 0.40 0.13 0.14 valve system wear damage (JASO standard M328 Rocker arm pad DR 1.4 91.7 31.9 34.7 摩 耗 Wear mg 8.1 15.0 9.7 8.8 Cam nose DR * 3 0 59.7 25.0 26.4 〃 Wear μm 2.3 16.3 6.3 5.8

[Table 5] (5) (6) (7)REO2 REO2 REO2  Belt deflection (＠ 10kgf) mm * 1 Engine side V-belt 19 19.1 19.3 Middle V-belt 19.5 19.1 19.3 Motor side V-belt 19 19 19.3 Engine vibration * 2 Lateral displacement mmp-p 0.05 0.06 0.06 Acceleration g 0.32 0.28 0.30 Vertical displacement mmp-p 0.13 0.11 0.13 Acceleration g 0.45 0.37 0.43 Back and forth displacement mmp-p 0.06 0.04 0.05 Acceleration g 0.26 0.24 0.26 Valve system wear damage Rocker arm pad DR 61.1 41.7 58.3 摩 耗 Wear mg 12.9 10.4 12.3 Cam nose DR * 3 54.2 29.2 56.9 摩 耗 Wear μm 12.4 5.4 10.4 In Tables 4 and 5, (1) uses standard engine oil.
(2) to (7) show the prototype engine
This is a prototype engine oil
In order to adjust the severity of
After slightly changing the "belt deflection",
Rocker arm pad, one factor of severity
D. R. Varies widely between 91.7 and 31.9.
On the other hand, in Tables 5 (5) to (7),
When the amount was slightly changed, one of the severe
Rocker arm pad D. R. Is 4
It varies between 1.7 and 61.1, especially in (7).
Rocker arm pad of case D. R. Is 58.3
The adjustment target value of the severity shown in Table 3 is 55 ±
It can be seen that it is within the range of 5.

Embodiment 2 (1) Apparatus used (see FIG. 5) In the apparatus of Embodiment 1, the entire engine portion is used, but in the apparatus of this embodiment, the engine is originally attached. Except for the cylinder block and the oil pan 15, a small oil pan 24 dedicated to this device was replaced. The toothed belt 26 for transmitting the driving force from the motor 6 is connected to the pulley 1 directly connected to the flange of the cam shut 25 on the front side of the engine.
Multiplied by six. As a result, it was possible to reduce the size and obtain a desktop type.

(A) Engine (based on JASO standard M328-91) Model Toyota 3A Total displacement cm ³ 1452 Number of cycles 4 Number of cylinders 4 Valve arrangement OHC rocker arm type 1-3-4-2 Maximum torque kgfm / rpm 12 0.0 / 3600 Remarks Remove cylinder block, crankshaft, piston, connecting rod, oil pan, flywheel, etc. from the engine. (B) Drive (i) Motor Model Toshiba 3-phase induction motor or equivalent Output / voltage kw / v 0 .75 / 200 rpm 1440 (ii) Transmission belt Model Genuine timing belt (toothed belt) Number 1 (iii) Pulley type Toothed pulley (2) Engine oil Same as in Example 1.

(3) Severity Adjustment Target Normally, engine vibration is handled as a combination of valve train vibration and crank system vibration, and the same applies to the equipment used in the first embodiment. However, since the cylinder block, crankshaft, oil pan, and the like originally provided are removed from the engine and only the upper structure of the engine is mounted as in the second embodiment, the tool used in the second embodiment is a valve operated engine. System vibrations can be treated as relatively pure. In the second embodiment, a crank system or three V
As shown in FIG. 5, the driving force of the motor is directly transmitted to the valve train (camshaft 25) by a single timing belt (toothed belt) 26 to evaluate D / R without inserting a belt. . The adjustment of the severity was performed by changing the tension of the timing belt by applying the load shown in FIG. 4 by pressing the rotor. The amount of deflection of the belt in Table 8 was determined by adjusting the pressing force.

[Table 7] REO1 REO2 rocker arm pad rating (DR) ≤5 55 ± 5

(4) Severity adjustment result

[Table 8] (1) (2) (3 ) (4) REO 2 REO2 REO2 REO 1 the amount of deflection of the belt (@ 10kgf) mm * 1 13.2 14.9 14.0 14.0 engine vibration * 2 sideways direction displacement mmp-p 0.06 0.06 0.06 0.06 Acceleration g 0.21 0.23 0.27 0.27 Vertical displacement mmp-p 0.10 0.12 0.12 0.11 Acceleration g 0.24 0.27 0.41 0.40 Valve train wear damage (according to JASO standard M328-91; the same applies hereinafter) Rocker arm pad DR 12.5 37.5 58.3 0.0 〃 Abrasion mg 9.0 11.2 12.4 8.3 Cam nose DR * 3 12.5 30.6 51.4 0.0 〃 Abrasion μm 3.7 8.7 11.9 2.5 In Table 8, change the amount of belt deflection and consequently change the values shown in the section of engine vibration. Thus, the rocker arm pad D.S.
R. Can be changed from 0 to 58.3 and the rocker arm pad D. in the case of (3). R. Indicates that the value falls within the range of 55 ± 5 which is the adjustment target value of the severity shown in Table 3.

[0015]

According to the present invention, the severity can be easily set to an arbitrary value with good reproducibility by controlling the frequency of the transmission member. Therefore, the wear test result of the valve train by the apparatus of the present invention is highly reproducible, accurate, and can provide highly reliable data.

[Brief description of the drawings]

FIG. 1 is a model diagram showing a specific example of a valve train wear test apparatus according to the present invention.

FIG. 2 shows an analysis model of a resonance generation phenomenon caused by an overlap between the engine valve train and the frequency of the belt.

FIG. 3 shows the relationship between the amount of deflection of the belt (load: 10 kgf) (unit: mm) and the severity in one specific example of the apparatus of the present invention.

FIG. 4 is a schematic diagram for explaining a method for measuring the amount of deflection of a transmission member according to the present invention.

FIG. 5 is a model diagram showing another specific example of the valve train wear test apparatus of the present invention.

[Description of Signs] 1 Engine (valve operating system) 2 Crankshaft 3 Pulley 4 V belt 5 Pulley 6 Motor 7 Vibrometer 8 Engine oil temperature controller 9 Pump 10 Heat exchanger 11 Accelerometer 12 Accelerometer 13 Inverter 14 Control Recorder 15 Oil pan 16 Pulley 17 Valve 18 Valve 19 Valve 20 Valve 21 Hydraulic control switch 22 Oil pressure gauge 23 Filter 24 Heated oil pan 25 Camshaft 26 Timing belt (toothed belt)

Claims (2)

(57) [Claims] 1. A valve train wear test apparatus comprising: an engine valve train; a motor for forcibly driving the engine valve train; and a transmission member for transmitting rotation of the motor to the valve train. A valve system wear test apparatus characterized in that a means for controlling the frequency of the valve system is provided so that the severity of the valve system can be adjusted. 2. An engine, an engine oil temperature control means, a pulley connected to a crankshaft or a camshaft of the engine, a motor, a pulley connected to a motor rotation shaft, a belt stretched between the two pulleys, and the belt Means for changing the tension of
A valve train wear test apparatus wherein the severity of the valve train can be adjusted.