Bearing gap measuring device and method

Patent metadata

Field	Value
Publication number	US-11221275-B2
Application number	US-202016750731-A
Country	US
Kind code	B2
Filing date	Jan 23, 2020
Priority date	Oct 21, 2019
Publication date	Jan 11, 2022
Grant date	Jan 11, 2022

Abstract

A bearing gap measuring device can measure a gap of a bearing to judge whether the bearing is damaged. The bearing gap measuring device includes: a pressure generating device configured to selectively supply a positive pressure and a negative pressure, which have a certain pressure, to an interior of a cylinder; and a displacement measuring device penetrating a cylinder head and applying a force to pull or push a piston by a sequential generation of a positive pressure and a negative pressure in the cylinder. In particular, the displacement measuring device includes a probe rod to contact with an upper face of the piston such that the probe rod is moved in a longitudinal direction to measure a height change amount of the piston.

First claim

What is claimed is:

1. A bearing gap measuring device, comprising;
a pressure generating device configured to selectively generate a positive pressure and a negative pressure, which have a certain pressure, to an interior of a cylinder; and
a displacement measuring device configured to penetrate a cylinder head and sequentially supply the positive pressure and the negative pressure to the cylinder so as to pull and push a piston in the cylinder,
wherein the displacement measuring device includes a probe rod configured to contact with an upper face of the piston such that the probe rod is moved in a longitudinal direction to measure a height change amount of the piston, and the measured height change amount of the piston is a measured bearing gap,
wherein the displacement measuring device comprises:
a body configured to penetrate the cylinder head and connected to the pressure generating device through a first end of the body, wherein a second end of the body is arranged in a combustion chamber of the cylinder so as to allow air flowing therethrough, and the probe rod is inserted into the body and configured to contact with the upper face of the piston through a lower end thereof so as to be moved in the longitudinal direction; and
a measuring gauge connected to the first end of the body and configured to measure a vertical displacement of the probe rod,

wherein:
the body has a stepped portion formed on an inner circumferential face thereof;
a stopper is formed on and protrudes from an outer circumferential surface of the probe rod and has a lower end supported on a stepped surface of the stepped portion;
the stepped portion has an inner diameter corresponding to an outer diameter of the probe rod;
the stepped portion has a body-penetrating hole formed in an inner circumferential surface thereof along a longitudinal direction of the body;
the stopper has an outer diameter corresponding to an inner diameter of the body; and
the stopper has a stopper-penetrating hole formed in an inner circumferential surface thereof.

2. The bearing gap measuring device of claim 1 , wherein the pressure generating device comprises;
a pneumatic pressure regulator configured to receive compressed air to output a preset positive pressure;
a negative pressure generator configured to suction air thereinto to generate a negative pressure;
a negative pressure regulator configured to output a negative pressure according to suction operation of the negative pressure generator; and
a three-way valve operated to selectively connect the pneumatic pressure regulator and the displacement measuring device or connect the negative pressure regulator and the displacement measuring device to generate the positive pressure or the negative pressure in the cylinder.

3. The bearing gap measuring device of claim 1 , wherein the body has a connecting hole formed in one side of an upper end and connected to the pressure generating device; and a predetermined gap is formed between an outer circumferential surface of the probe rod and an inner circumferential surface of the body when the probe rod is inserted into the body so as to form a passage configured to communicate with the connecting hole.

4. The bearing gap measuring device of claim 1 , wherein:
the body is coupled to the measuring gauge through an upper end thereof; and
a measuring jig provided on a lower end of the measuring gauge is in contact with an upper end of the probe rod and configured to allow the measuring gauge to measure the vertical displacement of the probe rod.

5. The bearing gap measuring device of claim 1 , wherein the body is provided to pass through a spark plug hole.

6. The bearing gap measuring device of claim 1 , wherein the displacement measuring device further comprises: a return spring configured to provide an elastic restoring force with respect to a vertical movement of the probe rod.

7. The bearing gap measuring device of claim 6 , wherein:
the return spring is fitted to the probe rod and supported between an inner face of the body and the stopper.

8. A method of measuring a gap using the bearing gap measuring device according to claim 1 , the method comprising;
generating a preset negative pressure in a cylinder by a pressure generating device in a state in which a piston in the cylinder is positioned at a specific point;
securing a position of the piston measured by a displacement measuring device in a state in which the preset negative pressure is generated;
releasing a supply of the preset negative pressure and generating a preset positive pressure in the cylinder by the pressure generating device; and
measuring a height change amount of the piston by the displacement measuring device in the state in which the preset positive pressure is generated,
wherein the measured height change amount of the piston is a measured bearing gap.

9. The method of claim 8 , wherein the piston is positioned at a point corresponding to a state in which both an intake valve and an exhaust valve are closed.

10. The method of claim 8 , wherein the piston is positioned at a top dead center where both of an intake valve and an exhaust valve are closed.

11. The method of claim 8 , wherein, in securing the position, the position of the piston is set to a top dead center where both of an intake valve and an exhaust valve are closed to secure the position.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Park Duk Jin
• Youn Sang Geun
• Kim Yong Sup

Classifications

• G01M15/06 Primary

  by monitoring positions of pistons or cranks · CPC title

• G01M15/04

  Testing internal-combustion engines · CPC title

• F16C2233/00

  Monitoring condition, e.g. temperature, load, vibration · CPC title

• G01M13/04 Primary

  Bearings · CPC title

• G01B5/146 Primary

  measuring play on bearings · CPC title