Patent ID: 7523843

Claim:
A grease gun having a housing defining an interior chamber and including a handle portion, the housing having at least one air inlet aperture and at least one air outlet aperture for placing the interior chamber in communication with the atmosphere, the grease gun comprising: an electric motor adapted to be disposed in the handle portion of the housing, the motor comprising: a motor housing having a first end wall, a second end wall and a body interconnecting the end walls, the end walls and the body having openings into the motor housing, a drive shaft extending from the second end wall, and a fan fixed to the shaft within the motor housing for drawing air through the motor housing: a wall integral with the handle portion of the housing and extending inwardly into the interior chamber, the wall engaging the body of the motor housing between the first end wall and the openings in the body so that the interior chamber is divided into a first air intake portion wherein the openings in the first end wall are in fluid communication with the atmosphere through the at least one air inlet aperture and a second exhaust air portion wherein the openings in the body and the second end wall are in fluid communication with the atmosphere through the at least one air outlet aperture, the wall providing a barrier to minimize air flow between the intake air portion of the interior chamber and the exhaust air portion; and a mounting plate mounted within the housing and having a first major surface and a second major surface and an edge wall extending between and interconnecting the first and second surfaces, wherein the fan induces air flow from the intake air portion of the interior chamber into the motor housing through the openings in the first end wall and from the exhaust air portion of the interior chamber into the motor housing through the openings in the second end wall and discharges the air out of the openings in the body, and wherein the mounting plate is secured to the second end wall of the motor so that the first major surface of the mounting plate faces the second end wall in spaced relationship and the motor shaft extends through an opening in the mounting plate, the cross-sectional area of the mounting plate is greater than the cross-sectional area of the second end wall but less than the cross-sectional area of the interior chamber of the housing so that at least a portion of the edge wall of the mounting plate is spaced from an interior surface of the interior chamber for defining a passage for air flow between the edge wall of the mounting plate and the interior surface of the chamber, and wherein the mounting plate deflects a portion of the discharged air into the openings in the second end wall.