JPH0359436A - Wear testing device for engine - Google Patents

Abstract

PURPOSE:To measure the quantity of wear efficiently by setting a period wherein a magnetic field is impressed to magnetostrictive alloy pressing a piston ring against the inner peripheral surface of a cylinder and the intensity of the magnetic field to a period where in explosion pressure is applied to the piston ring and its pressing force. CONSTITUTION:When a cylinder 2 moves and an elastic contact piece 8 enters the recessed part 2b of the cylinder 2, a switch 9 is closed to turn on an electric circuit and a current flows through a coil 7; and a magnetostrictive metal rod 5 expands through the operation of a magnetic field produced with the current and the piston ring 3 is pressed against the inner peripheral surface of the cylinder 2 through a push rod 6. This period corresponds to the position of the actual ignition and combustion process of the engine, the pressing force of the rod 5 is made to correspond to the explosion pressure in the combustion chamber of the actual engine by adjusting the intensity of the magnetic field through a variable resistor 11, and the continuance of the pressing force by the rod 5 is set matching the actual engine according to the shape of the recessed part 2b. The wear of the cylinder 2 and rod 3 is measured after this operation is operated for a specific time to reproduce the wear state by simulation.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention simulates the wear of piston riffs and cylinders that occur in a commercial engine using a testing device that provides wear conditions similar to those of an actual engine. , relates to an engine 814 test device that measures this wear condition.

(Conventional Technique RPI) Engines such as those used in R1 vehicles have recently shown a remarkable trend toward higher output, and the combustion explosion pressure of the fuel during engine operation and the pressure during the compression process have become higher.

The pressure in the combustion chamber of the engine acts on the front surface of the piston link fitted in the link globe of the piston and presses the piston link against the inner peripheral surface of the cylinder. Ignition/combustion process, v
The P-air process changes in a complex manner, and the pressure of the explosion during the ignition and combustion process forces the piston ring against the inner surface of the cylinder, causing the piston to ignite and burn. When the piston is at a position of about I, the portion of the cylinder facing the first piston link experiences the most wear.

Conventionally, in order to evaluate the durability of an engine, the engine is operated for a short period of time, and the engine is disassembled every predetermined operating time to inspect the piston link and cylinder, and the friction L thereof is measured.

In addition, Japanese Utility Model Application Publication No. 63-99206 discloses that in a two-stroke engine, the thickness of the bisted cylinder is measured using a clearance gauge built into the inner pores of the cylinder inner circumferential surface.
It has been proposed to measure it quasi-magnetically.

(Problem to be solved by the invention) In the conventional inspection method, the engine must be actually operated, disassembled at predetermined operating hours, and the piston links and cylinders must be inspected, which requires a lot of labor and expense. Moreover, with the method described in the above-mentioned publication, it is not possible to measure the wear condition of the cylinder, even though it is possible to measure the fist condition of the piston ring.

The Suekan IJi solves the above problems and reproduces the wear of piston rings and cylinders using a simulation device with the same wear conditions as the 'is engine, and measures it with high efficiency. (The purpose is to provide a highly functional engine wear testing device.

[Means and effects for solving the problem] The present invention provides a pressing means made of a magnetostrictive alloy for pressing a piston ring fitted on a piston that reciprocates relative to the cylinder against the inner circumferential surface of the cylinder. There is an engine wear test device C in which the timing and strength of the magnetic field applied to the ma-gold alloy are set to be similar to the timing and pressing force applied to explosion pressure or piston rings in an actual engine.

When a magnetic field is applied to the magnetostrictive alloy of the pressing means installed on the piston while reciprocating the piston fitted with the piston ring relative to the cylinder, the magnetostrictive alloy deforms and presses the piston/cylinder against the inner peripheral surface of the cylinder. . The piston ring is pressed by this pressing means at the time when the magnetic field is applied to the magnetostrictive alloy, and the pressing J-E force is determined by the strength of the magnetic field applied to the magnetostrictive alloy. l! I! Therefore, the wear conditions of this engine wear test device can be set to match the explosion pressure of the combustion chamber in an actual engine. It matches with accuracy.

Therefore, even if you do not measure the L''C wear value when the engine is running, this wear testing device can simulate the wear condition with high accuracy and measure the wear rate efficiently.

(Example) Embodiments of the present invention will be described with reference to the drawings.

Figure 1 is a cross section of the wear test device, showing one #' of piston l.
-1; The first ring 3 of the piston ring is fitted into the ring clove near the end, the piston l is fixed to the support base 4, and the cylinder 2 into which the piston l is fitted is mounted eccentrically, although not shown. A spring is provided to press the cam 12, and the eccentric cam 12 reciprocates by rotating! #1 mechanism or the like drives the cylinder 2 up and down in the figure, so that it moves m with the piston ring 3 fitted on the piston l.

The position where the piston ring 3 faces the cylinder 2 in the figure is
In an actual engine, at the position during the ignition/combustion process, it enters the ringetal lobe, and due to the explosion pressure acting on the back of the piston link 3, it is pressed most strongly against the piston link 3 or the inner peripheral surface of the cylinder 2, and the opposite cylinder The part 2a is the position where the most wear occurs.

A rod 5 made of a magnetostrictive alloy that expands and contracts by air is installed on the piston l, and bush rods 6 and 6 are installed on both sides of the rod.
are installed by inserting them into the holes that connect to the bottom of the ring globe of the piston l, and the other ends of these bushing rods 6 are brought into contact with the inside of the piston ring 3, and when the strained alloy rod m is extended, the bushing rods 6 The inside of the piston ring 3 is pressed through the piston ring 3 to enlarge its diameter.

Further, a coil 7 is disposed around the magnetostrictive alloy rod 5, and in the circuit of the coil 7 having the power supply lO1 variable resistor 11, the tip of the elastic contact piece 8 is formed in a recess provided on the outer peripheral surface of the piston ring 3. A normally open switch 9 is provided which closes when inserted into i2b.

The position where the switch 9 closes is located in the recess 12 provided in the cylinder 2.
It can be set arbitrarily depending on the position of b. In the figure, it is set at 10 positions during the ignition and combustion process in an actual engine.

21J shows a plan view of the main part of the mechanism that expands/reduces the diameter of the piston link 3 to change the pressing force on the piston ring 3, and FIG. 3 shows the relationship between the strength of the magnetic field and the amount of deformation of the magnetostrictive alloy. It shows a relationship.

Next, the operation of the wear test device will be explained based on FIG.

The eccentric cam 12 is rotated to reciprocate the piston link 3 downward by 12 degrees, and the cylinder 2 is caused to slide on the west peripheral surface of the piston ring 3. When the elastic contact piece 8 is in contact with the outer peripheral surface of the piston ring 3, the switch 9 is open, so no magnetic field is applied to the magnetostrictive alloy port 5, and the piston ring 3 receives the pressing force of the bushing rod 6. There is no action, and the piston ring 3 maintains its normal shape. When the cylinder 2 moves and the elastic contact piece 8 enters the fourth part 2b of the cylinder 2, the switch 9 is closed and the electric circuit is turned on, and a current flows through the coil 7. The magnetic field generated by this current causes magnetostriction. The alloy rod 5 extends and presses the piston link 3 against the inner peripheral surface of the cylinder 2 via the push rod and rod 6. This period is the position in the ignition/combustion process of the engine, and the pressing force of the magnetostrictive alloy lot 5 is adjusted by the variable resistor 11 to adjust the strength of the magnetic field to correspond to the actual explosion pressure in the combustion chamber of the engine. Furthermore, the duration of the pressing force by the magnetostrictive alloy rods I to 5 is set depending on the shape of the four parts 2b and the actual engine.

When the piston link 3h)"i is moved and the switch 9 is opened, the magnetic field of the coil 7 disappears, the magnetostrictive alloy rod 5 contracts, the piston ring 3 returns to its normal shape by its own elasticity, and the inside of the cylinder 2 Release the pressing force on the circumferential surface.

After operating this wear test device for a predetermined time, cylinder 2
When the wear of the piston ring 3 is measured, the wear in the 2ail of the cylinder 2 is the largest, and it becomes possible to simulate the wear state of the cylinder 2 and piston ring 3 similar to that in an actual engine.

In the above embodiments, the magnetostrictive alloy is shown in a loft shape and its expansion and contraction are utilized, but other shapes that utilize the deformation of the magnetostrictive alloy are also possible. Further, in the above embodiment, the piston l is fixed and the cylinder 2 is reciprocated, but the cylinder 2 is fixed and the piston l is moved back and forth.
Of course, it is also possible to reciprocate through the connecting rod and piston pin.

If a piston incorporating the mechanism for pressing the piston ring 3 by the magnetostrictive alloy rod 5 shown in FIG. Since a sufficient pressing force on the cylinder can be obtained, a piston link with low tension and low rigidity in the circumferential direction can be used to create an engine with low friction*resistance.

(Effects of the Invention) The present invention allows the wear test device to be set to wear conditions similar to those during actual engine operation, so the wear test device can simulate wear with good accuracy and efficiently spread wear. Is there an effect that can be measured?

[Brief explanation of drawings]

11th. Il! l is an example of final perfect rjl L*Jff
i A cross-sectional view of the test device; Figure 2 is a plan view of the main parts of Figure 1;
FIG. 3 is a diagram showing the relationship between the strength of the magnetic field and the amount of deformation of the magnetostrictive alloy. 1. Piston 2. Silicator 2a: Wear part 3 Niviston link 5: Magnetostrictive alloy lot 7: Coil 9: Switch 11: Variable resistor 2b, 4 parts 4, Support stand 6: P-Socket: L lot 8: Elastic contact piece Kazutomo Umikawa, patent attorney and patent attorney

Claims (1)

[Claims] A pressing means made of a magnetostrictive alloy is installed on the piston to press a piston ring fitted on a piston that reciprocates relative to the cylinder against the inner circumferential surface of the cylinder, and the timing and strength of the magnetic field are controlled by applying a magnetic field to the magnetostrictive alloy. An engine wear test device characterized in that the timing and pressing force at which explosive pressure is applied to a piston ring are set to be the same as in an actual engine.