JPS63187134A - Apparatus for testing scuffing of piston ring - Google Patents

Abstract

PURPOSE:To evaluate the scuffing of a piston ring, by supporting the shaft vertically provided on the upper part of a piston by a bearing and fixing the housing receiving the bearing to a cylinder block through a spacer. CONSTITUTION:The shaft vertically provided on the upper part of a piston 2 is supported by a bearing 7 and the housing 6 receiving the bearing is fixed to a cylinder block 4 through a spacer 5 to constitute a scuffing testing appara tus. When the piston 2 moves up and down by the driving of a motor through a crank shaft and a cone rod, the oscillating of the piston is prevented by this constitution of the apparatus and the evaluation of the scuffing of a piston ring 1 can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a scuffing test device for piston rings in a reciprocating internal combustion engine.

[Prior Art] Occurrence of scuffing of piston rings when starting an internal combustion engine at a low temperature has become a problem. For this reason, it is good if the scuffing test can be performed using an actual machine using a low-temperature bench, but if such equipment is not available, the lubricating oil will solidify at low temperatures (approximately -30°C), resulting in no i1J] Based on the assumption that it will be close to a smooth state,
Evaluation tests are being conducted using the non-lubricant motoring method using actual pistons and cylinder blocks. (The motoring method is not based on fuel combustion or explosion, but instead uses a motor to rotate the crankshaft as in the first plan.
This is a method of reciprocating a piston. ) [Problems to be Solved by the Invention] However, in the conventional motoring method, the piston skirt contacts and slides against the cylinder wall due to the oscillating motion of the piston, resulting in scuffing before the piston ring. , ~ It was difficult to evaluate the important piston ring.

[Means for Solving the Problems] In view of the above, the present invention aims to prevent the piston from swinging, reproduce the behavior of only the piston ring and cylinder, and evaluate scuffing. According to the present invention, there is provided a scuffing test device for a bisto flange, in which a shaft provided vertically at the top of a piston is supported by a bearing, and a housing that accommodates the bearing is fixed to a cylinder block via a spacer. Ru.

[Operation] When the piston moves up and down through the crankshaft and connecting rod due to the drive of the motor, it tries to swing, but the piston also swings vertically due to the vertical movement of the shaft installed vertically at the top of the piston and supported by bearings. It moves up and down. Therefore, the piston is prevented from swinging in the U direction and does not collide with the cylinder wall, and only the piston ring moves inward with the cylinder wall.

[Example] Embodiments of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the top surface of the crown portion of an actual piston 2 with a piston ring 1 mounted thereon is cut flat, and a shaft 3 is vertically attached using bolts. The shaft 3 is hollow and lightweight, and its surface is hardened by carburizing and quenching.

On the other hand, a housing 6 is fitted and fixed to the actual machine cylinder block 4 via a spanner 5. In this case, the housing 6 consists of a cylindrical nose 61 that accommodates the linear ball bearing 7 and a disc-shaped flange 62 that is the joint part with the spacer 5.

A linear ball bearing 7 housed in the housing 6 supports the shaft 3 and serves as a guide so that the shaft moves up and down vertically.

A bearing presser 8 is blown into the upper edge of the housing 6 to prevent the linear ball bearing 7 from moving in the sliding direction.

Further, the cylinder block 4, the space length 5, and the housing 6 are joined together, and the housing 6, the bearing, and the presser foot 8 are joined together by bolting at the locations indicated by dashed lines.

Although the above configuration prevents the piston 2 from swinging and makes it possible to evaluate the scuffing of the piston ring 1,
Since the spacer 5, housing 6, bearing 7, etc. are machined and joined with a certain degree of fitting tolerance, the center line of the bearing may deviate from the center line of the cylinder bore, and in that case, some oscillation occurs. Therefore, in order to reliably prevent collision between the piston 2 and the cylinder wall 41, it is desirable to cut the piston skirt 21 to reduce the skirt diameter.

The scuffing test using the apparatus of the present invention is carried out by the motoring method as shown in FIG.

That is, the propeller shaft P1 and the crankshaft C are rotated using the motor M as a driving source, and the apparatus E and the piston ring of the present invention are attached to the cylinder block 4 and piston 2 for an actual machine and are driven.

[Effects of the Invention] As described above, according to the test device of the present invention, the sliding movement of the piston ring close to that in actual machine operation can be reproduced, so that the accuracy of evaluating the scuffing resistance of the piston ring is improved.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of the main part of the device of the present invention, and FIG. 2 is a schematic diagram illustrating the motoring method. Explanation of symbols 1... Piston ring, 2... Piston, 3...
Shaft, 4...Cylinder block, 5...Spaner, 6...Housing, 7...Bearing, 8...
・Bearing holder.

Claims (1)

[Claims] A piston ring scuffing test device in which a shaft provided vertically above the piston is supported by a bearing, and a housing containing the bearing is fixed to a cylinder block via a spacer.