Denso Corporation

Yasuo Katoh

Tomohiro Itoh

Ryoyuu Kishi

Keiichirou Ishihara

A leak hole determination device in an evaporated fuel processing system. The leak hole determination device includes: a first pressure detector for detecting a first pressure in a fuel tank; a second pressure detector for detecting a second pressure in a canister; and a leak hole determiner for determining whether a leak hole is present. The leak hole determiner determines, after a limit pressure timing subsequent to a depressurization operation for depressurizing an inside of the system, whether a leak hole is present by using a difference between a change speed of a first pressure detected by the first pressure detector and a change speed of a second pressure detected by the second pressure detector.

Leak hole determination device of evaporated fuel processing device

A pressure sensor for an evaporated fuel leak detector includes a sensor unit, a case, and a sealing resin. The sensor unit has a pressure receiving portion, a plurality of conduction terminals, and a mold resin portion. The case has a fluid flow path and a housing recess. Each remaining inner wall surface of the housing recess except for an inner wall surface on the conduction terminal side is provided with an inclined surface and a vertical surface, in a cross section along an axial direction perpendicular to a pressure receiving surface of the sensor unit. The inclined surface is inclined inward as toward a pressure receiving side. The vertical surface extends from the end of the inclined surface on the pressure receiving side to define a filling gap in which the sealing resin is filled between the side surface of the mold resin portion and the vertical surface.

Pressure sensor for evaporated fuel leak detector

A pressure sensor for an evaporated fuel leak detector is used for checking a leak in a fuel tank and a canister. The pressure sensor includes a sensor unit, a case, and a sealing resin. The sensor unit includes a pressure receiving portion for detecting a pressure of a fluid applied to a pressure receiving surface, and a mold resin portion covering a surface of the pressure receiving portion except for the pressure receiving surface. The case has a fluid flow path for introducing the fluid to the pressure receiving surface, and a housing recess in which the sensor unit is accommodated. The sealing resin is arranged in the housing recess, to at least cover a back surface of the mold resin portion located on an opposite side of the pressure receiving surface.

A pressure sensor for an evaporated fuel leak detector is used for checking airtightness in a fuel tank and a canister. The pressure sensor includes a sensor unit, a case, and a sealing resin. The sensor unit has a pressure receiving portion, a plurality of conduction terminals, and a mold resin portion. The case has a fluid flow path and a housing recess. A buffer recess having an outer shape larger than the outer shape of a pressure receiving surface is formed at a pressure receiving side Lof the bottom of the housing recess. Further, a protruding cylinder portion protruding into the buffer recess toward a back side Lis formed at an outer edge of an opening end portion of the fluid flow path on the back side L

A pressure sensor for an evaporated fuel leak detector is used for checking a leak in a fuel tank and a canister. The pressure sensor includes a sensor unit, a case, and a sealing resin. The sensor unit has a pressure receiving portion, a plurality of conduction terminals, and a mold resin portion. The case is provided with a fluid flow path and a housing recess. The case has an annular inner wall surface that defines the housing recess and surrounds a side surface of the mold resin portion. The inner wall surface of the case is provided with a stepped surface that is parallel to the pressure receiving surface or is inclined by an internal angle of less than 90&#xb0; with respect to the pressure receiving surface, in a cross section along a direction perpendicular to the pressure receiving surface.

A vane pump includes: a casing forming a pump chamber therein; a rotor arranged inside the casing to rotate eccentrically with respect to the casing; and a plurality of vanes configured to rotate with the rotor and slide on an inner side surface of the casing. At least one of Formula (1): l&#x2264;(b/a)&#xd7;k and Formula (2): l&#x2264;(c/a)&#xd7;j is satisfied, where 'a' represents a height of the pump chamber, 'b' represents a height of the rotor, &#x201c;c&#x201d; represents a height of the vane in a rotation axis direction of the rotor, and where &#x201c;l&#x201d; represents a linear expansion coefficient of the casing in the rotation axis direction, &#x201c;k&#x201d; represents a linear expansion coefficient of the rotor in the rotation axis direction, and &#x201c;j&#x201d; represents a linear expansion coefficient of the vane in the rotation axis direction.

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Kariya, Japan

Yasuo Katoh