Abstract: An improved structure of a sand blast gun includes a body, a guide tube accommodated in the body in a longitudinal direction, and a stop valve disposed in a radial direction. The stop valve has two guide posts. A shaft having a sleeve fitted on the outside straddles over upper portions of the guide posts. The guide posts are respectively fitted with pressure springs and inserted into holes of the body. An urging top end is firstly fixed on a center of a securing plate that is screwably mounted at the bottom side of the guide posts such that the urging top end extends into a radial round hole of the body to urge against a catgut tube to close the passage. When a trigger of the sand blast gun is pulled, it pushes the shaft and the guide posts to cause the pressure spring to retract to thereby cause the securing plate on the bottom of the guide posts and the urging top end to displace outwardly.

Abstract: An improved detergent recycling apparatus for parts washing machines includes a detergent recycling apparatus additionally provided with a control box, a manifold, a first control valve, an extension tube, a spray gun, a second control valve, a third air duct and a secondary serpentine hose. The control box is mounted on one side of the detergent recycling apparatus, and the manifold, first control valve, silencer, extension tube and second control valve are assembled thereto. The manifold is internally provided with an air vent and has a high pressure air inlet at one end thereof. The manifold includes front, intermediate and rear threaded holes. The first control valve is screwably secured to the rear threaded hole and communicates with an extraction pump via a first air duct. The extension tube is screwably locked to the front threaded hole at one end and connected to the spray gun at the other.