Abstract: A water cooling head with sparse and dense fins, including a main body, a first fin set and a second fin set. Wherein a chamber is formed inside the main body, the main body has a first plate and a second plate, the main body forms an inlet channel and an outlet channel, so that the cooling water passes through the chamber. The first fin set and the second fin set are arranged in the chamber, and the first fin set and the second fin set are connected to the first plate respectively. The first fin set comprises several first fins spaced apart, the first fins divide the chamber to form several first channels. The second fin set comprises several second fins spaced apart, the second fins divide the chamber to form several second channels. The water cooling head can increase the overall heat sinking efficiency.

Abstract: A plastic tube cutter comprises a housing, a blade holder and a blade, the blade is fixed to the connecting portion of the blade holder and is clamped between the clamping block and the locking piece. And then the blade, the clamping block and the locking piece are fastened together by screwing fasteners through the holes of the blade holder and the clamping block and into the threaded holes of the locking pieces. By pressing the lever, the blade holder will be moved to a predetermined position at which the fasteners are aligned to the through holes of the housing, so that the blade is reassembled easily by unscrewing the fasteners through the through holes, without dismantling the housing.

Abstract: A test assembly includes a valve and a piston received in a casing. The valve includes a main passage and a flexible seal film is mounted to an end of the valve. The seal film seals the main passage and has two apertures. A radial passage is defined through the valve and communicates with the main passage. A sub-passage is located in parallel with the main passage and communicates with the radial passage and one of the apertures of the seal film. A control member is rotatably and radially inserted in the valve and has a first path radially through the shank of the control member and communicates with the main passage. A second path is defined in half way of the shank and communicates with the first passage.

Abstract: A test assembly includes a valve and a piston received in a casing. The valve includes a main passage and a flexible seal film is mounted to an end of the valve. The seal film seals the main passage and has two apertures. A radial passage is defined through the valve and communicates with the main passage. A sub-passage is located in parallel with the main passage and communicates with the radial passage and one of the apertures of the seal film. A control member is rotatably and radially inserted in the valve and has a first path radially through the shank of the control member and communicates with the main passage. A second path is defined in half way of the shank and communicates with the first passage.

Abstract: A vacuum test assembly includes a body (20) having a piston (22) movably received therein and a valve (30) is received in the body with a gauge (31) connected thereto. The valve has a passage (32) which defines an opening at an end of the valve. An annular groove (33) is defined in an outer periphery thereof. A seal film has a skirt portion having a clamp flange (41) which is engaged with the annular groove. Two apertures (42) are defined through the seal film.

Abstract: A pipe cutter includes a slide slideably engaged in a housing and a cutting blade secured to the slide. A hand grip may move the cutting blade forward gradually for cutting a pipe. The housing includes one or more openings for engaging with one or more fasteners and for allowing the fasteners to be engaged into the housing and to secure the cutting blade to the slide without disassembling the whole housing. A retaining plate may be secured to the slide and engaged with the cutting blade for securing the cutting blade in place. A panel includes one or more screw holes for engaging with the fastener and for allowing the fastener to further secure the cutting blade and the slide together.

Abstract: A pipe cutter includes a jaw formed on one end of a handle and includes a cutter blade pivotally coupled to the handle and having a cutter edge adapted to be moved toward the jaw for cutting a pipe. The cutter blade includes a number of ratchet teeth formed in the bottom peripheral portion and includes a depression having two end portions. A handgrip includes an actuator for engaging with the ratchet teeth and for rotating the cutter blade. A pawl may prevente the cutter blade from rotating in the reverse direction. An adjusting member is pivotally coupled to the handle and includes a protrusion slidably engaging with the depression of the cutter blade and engageable with either of the end portions of the depression for adjusting the distance between the cutter edge and the jaw.

Abstract: A pipe cutter includes a hollow head portion having a first and second ends and a passage way is formed along a longitudinal axis thereof. A jaw element is formed on the first end of the head portion thereby defining a mouth for receiving a pipe to be cut. A blade means has a blade received therein, the blade slidably engaged in the passage way of the head portion. Two handles, each has two ends, one end thereof pivoted to the head portion. A transmission means has first and second ends, the first end pivoted to the blade means and the second ends pivoted to the handles, such that the transmission means converts pivotal movements of the handles into linear movement of the blade means.

Abstract: A cutting device for a plastic pipe or the like includes a gun-like body having a forward fixed jaw member and a rear movable member carrying a cutting element preferably of a triangular shape and having two converging cutting edges. The movable member can be moved forward by operating a handle. In operation, the cutting element penetrates the object and then cut the object efficiently.