Abstract: A nozzle of a spray gun includes an outer part connected to the spray gun. The outer part includes a neck portion formed therein. A neck hole is formed through the neck portion. Multiple paths are defined through the neck portion. The neck portion divides the inner space of the outer part into a first room and a second room. A tube extends through the neck hole and the tube. A swing member is located in the first room and connected to the rear end of the tube. An inner part is located in the second room and connected to the front end of the tube. High pressure fluid is introduced into the first room to swing the swing member. The tube and the inner part swing with the swing member. The high pressure fluid enters into the second room via the paths and spray out from the outer part.

Abstract: A device for adjusting air pressure of a spray gun, and a method for adjusting air pressure of a spray gun includes installing an air adjustment valve in a first chamber located at the rear end of a rear path of the spray gun. The spray gun is connected with a compressor and the users operates the air adjustment valve to reduce the pressure in the first chamber, and the second chamber is supplied with a pre-set pressure so as to stably provide constant pressure to the front path to proceed paint spraying task.

Abstract: A valve unit includes a valve body with a plate located in a tubular portion of the valve body. The tubular portion has multiple notches defined in the outside there. A knob has a space defined therein and is threadedly mounted to the tubular portion. The knob has a groove defined in the outside thereof. A first hole and a second hole are respectively defined through knob and communicate with the groove. A resilient member is engaged with the groove and two ends of the resilient member are respectively engaged with the first and second holes. A spring is biased between the plate and the knob. The contact portion is engaged with the notches to generate sounds when rotating the knob.

Abstract: A blow gun includes a body with a top path and a bottom path, and a volume adjustment device is installed between the top and bottom paths. The volume adjustment device is in contact with a press rod which has one end pivotably connected to the body. The opening of the press rod is controlled by operation of the volume adjustment device so as to change the volume of the pressurized air. The press rod can also be locked at a position so that it is not activated unintentionally.

Abstract: A male connector includes a connecting member which has a cone-shaped exit defined therein and the connecting member is connected to a pipe connector to define a space therebetween. A movable member has a cone-shaped end and multiple openings are defined through the wall of the movable member. The movable member is movably located in the space and the cone-shaped end seals the cone-shaped exit of the connecting member along the direction of the fluid. The cone-shaped end has multiple grooves or release holes to slowly release the residual pressurized fluid of the pneumatic tool or the hydraulic tool so as to safely separate the male and female connectors and mitigate the noise.