Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Mitsubishi Denki Kabushiki Kaisha

Mauri Ukonmaanaho

Kiyoshige Shimaoka

Tsutomu Tominaga

Masayasu Miyajima

Kazuhiro Geshi

Tomohide Maruyama

This invention relates to a leak tester for testing the tightness of a test object such as a fuel feed apparatus for an internal combustion engine, and specifically to a leak tester for testing the air tightness of a fuel feed apparatus provided with a first opening and a second opening and having a space portion between the first and second openings. The leak tester is provided with a master (reference chamber) having substantially the same internal volume as the fuel feed apparatus, a pneumatic pressure source for supplying air of a predetermined pressure to the test object through the first opening and also to the master, a differential pressure leak tester for measuring a pressure difference between a pressure of the fluid within the test object and that within the master, and a flow meter for measuring a flow rate of air flowing out of the fuel feed apparatus through the second opening; and the leak tester detects leakage of air from the test object other than that through the second opening on a basis of the pressure difference and the flow rate.

Leak tester and leak testing method

A high-pressure pump unit allowing an oiltight test for a high-pressure piping system after assembly without damaging parts which do not have a pressure resistance construction. The pump unit comprises a high-pressure pump (11) for sucking fuel and pressurizing it, a high-pressure regulator (14) coupled through a fuel consuming section (3, 4) to the outlet side of the high-pressure pump for regulating the pressure to the fuel discharged under a high pressure from the high-pressure pump, a fuel pressure switching valve (15) placed in a bypass extending from an upstream side of the high-pressure regulator to a downstream side thereof for opening and closing the bypass in accordance with an operational mode, a check valve (12) located between the high-pressure pump and the fuel consuming section, and a check valve (17) placed between an exit passage (18) of the high-pressure regulator and a passage (19) through which the fuel in the outside of the high-pressure section of the high-pressure pump is discharged to the outside of the high-pressure pump.

High-pressure pump unit and test method therefor

Growing community of inventors

Tokyo, Japan

Mauri Ukonmaanaho