Abstract: An oil return loop of a hydraulic cylinder which includes a plurality of equiangularly spaced V-shaped oil return grooves at the inside wall of an inner cylinder of the hydraulic cylinder for guiding saturated hydraulic oil to the outer cylinder of the hydraulic cylinder when the piston rod of the hydraulic cylinder is extended out. Each of V-shaped oil return grooves has two smoothly arched chamfered edges respectively disposed at connecting areas between the V-shaped oil return grooves and the inside wall of the inner cylinder to facilitate movement of the oil seal ring of the piston of the piston rod over the oil return loop.

Abstract: A hydraulic circuit system for one-touch jack and its structure has an inlet circuit, a return circuit and an overload protection circuit with a hydraulic cylinder, a piston rod, a sequence valve, a safety valve and a relief valve, in which the inlet circuit extends from an outer reservoir of a hydraulic cylinder via a check valve to connect to an oil chamber of a manual pump. The oil chamber of the pump is connected to an oil guide tube via another check valve, the oil guide tube is inserted into an inner oil chamber formed in a piston rod to form a closed circuit. The oil chamber of the pump is connected to an inner chamber of the hydraulic cylinder via a sequence valve and the inner chamber is connected to the outer reservoir via a check valve.

Abstract: A carrying box which includes a box body adapted for holding a portable computer and computer accessories, a support board hinged to one side panel of the box body and adapted to supporting the box body on a seat, a strap adapted to securing the box body to a back of a seat, an inner cover board hinged to one side of the box body and adapted to close the box body, the inner cover board having an expandable file pouch and pen loops on the inside, and a rigid outer cover board having a flexible linking portion hinged to one side of the box body opposite to the inner cover board and a paper clip on the inside.

Abstract: The invention targets at providing a foldable structure for a conventional exercise treadmill, especially for a exercise treadmill that has a motor mounted in the front and fixed type armrests. According to the invention the main frame of the exercise treadmill is provided at the front end with a U-shaped base to which armrests are attached. Further, a pressure rod and a telescopic support tube are disposed on two sides of the U-shaped base and the main frame. To fold the exercise treadmill, users lift the rear end of the main frame to a predetermined inclination and then by means of the release of the pressure energy of the pressure rod the main frame will automatically move to an upright folded position juxtaposed with the armrests. Hence the exercise treadmill structure of the invention can reduce the space it occupies when not in use for convenience in storage or delivery. Furthermore, the spread structure can be firmly fixed by a movable steel ball of the support tube.

Abstract: A hydraulic circuit system for one-touch jack and its structure has an inlet circuit, a return circuit and an overload protection circuit with a hydraulic cylinder, a piston rod, a sequence valve, a safety valve and a relief valve, in which the inlet circuit extends from an outer reservoir of a hydraulic cylinder via a check valve to connect to an oil chamber of a manual pump. The oil chamber of the pump is connected to an oil guide tube via another check valve, the oil guide tube is inserted into an inner oil chamber formed in a piston rod to form a closed circuit. The oil chamber of the pump is connected to an inner chamber of the hydraulic cylinder via a sequence valve and the inner chamber is connected to the outer reservoir via a check valve. When the maximum effect capacity of the oil chamber of the piston rod, a single touch of the pump can raise the hydraulic jack to the required loading position for raising at no load or light load conditions.

Abstract: A folding device for treadmill, particularly a easy and ready-to-fold folding device to fold handle frame on treadmill so that the handle frame can be folded to the surface of treadmill body to minimize packing volume and transportation cost as well as to save space requirement for storage.

Abstract: A control switch for an electric winch includes a handle, a set of forward and reverse push button switches and a switch box. The switch box includes a top cover and a bottom cover. The top cover is provided with a set of polarize conducting plates for DC voltage and another set of polarized conducting plates for motor wiring. The bottom cover is provided with two grooves for holding two sliding blocks, respectively. Each of the two sliding blocks is provided with conducting wipers and springs. The movement of the sliding blocks corresponds to the pushing of the forward button or the reverse button. Thus when one of the buttons is pushed, a circuit connection inside of the switch box is changed, providing control of the coiling, uncoiling and braking of a winch cable.

Abstract: Electrically powered or manually driven clutch and brake mechanism for an electric wince cooperate with a transmission mechanism. The clutch mechanism is provided with a thrust bearing on a clutch shaft and a large clutch gear is then inserted thereon. A lining plate is attached to a clutch plate of the large gear and a pinion gear is attached tightly to the lining plate. Another thrust bearing is placed behind the pinion gear and a compression spring is inserted on the clutch shaft. The large and the pinion gears can be pushed tightly together or loosened as a function of resiliency of the spring. A clutch hand wheel can be provided for manual operation. In addition, the brake mechanism is designed such that a rotating shaft of a motor is provided with a disc brake which has a unidirectional bearing. The disc brake can be squeezed tightly by disc pads.

Abstract: A hydraulic jack with a restorable lever and a retaining device includes a positioning blind hole provided on one side of a base. The blind hole holds a compression spring which acts between the base and a lever holder. A supporting post on one side of the base is provided with a pin hole for accepting a retaining pin to hold the lever holder in place. When the retaining pin is removed for operation, the stored energy of the compression spring is released so that the lever is lifted up automatically each time when it is pressed downwardly. A V-shaped spring clip connects the lever to the lever holder. A forward end of the lever is provided with a gripping hole and has two side notches, thus shaping the gripping hole to enable the lever to be used for opening and closing of a releasing valve. A foot pedal or a handle can be attached to an end of the lever for ease of operating the hydraulic jack.

Abstract: A hydraulic jack safety valve structure provided within the one-way valve body of the jack. The one-way valve has a cylindrical shape and is provided on the pump base of the jack. An annular slot is provided in the cylindrical body. The annular slot is provided with an oil inlet port and an L-shaped oil inlet passage which extends from the top surface of the one-way valve. An oil discharge port is provided so that the top of the one-way valve communicates with the bottom. The wall of the annular slot is provided with a safety oil discharge port which communicates with the oil discharge passage. Inside the safety oil discharge passage, a push pin and a safety spring are inserted in proper sequence. An adjustment screw is used to secure the pin and spring in place. The push pin, inside the safety oil discharge passage, provides flow guidance so that the flow of the hydraulic discharge fluid can be smooth.

Abstract: A storage case includes a case body and a top cover hinged together for holding parts of a detachable jack. The top cover has a beveled front side, three recesses and holes in the beveled front side, three longitudinal steel column chambers of different respective lengths extended from the holes for holding the steel columns of the jack, and three stop strips extending upwardly from respective bottom sides of the recesses for stopping and retaining the steel columns in the longitudinal steel column chambers.

Abstract: A twin-type buffering or dampening pad is made from very tough rubber material. The pad is highly deformable and flexible and particularly suitable for installation between the foot board and the side frame of a running machine to absorb or dampen shock. The pad includes a pair of symmetrical cylinders integrally connected by a reinforced rib and arranged inverted relative to each other. Each of the cylinders has a flat surface at one end, which has a screw hole at the center and a convex or semi-spherical surface at the opposite end. The semi-spherical surface on one of the cylinders is flush at its apex with the adjacent flat surface on the other cylinder to simultaneously contact a face to efficiently absorb the shock produced from all directions by random stepping force when a user runs on the running machine.

Abstract: An improved one-way valve structure for a hydraulic jack includes a stepped inlet end at a L-shaped intake passage for fixing of a filter. The diameter of the filter is slightly smaller than the inner diameter of the intake passage. The filter is designed so that it can be firmly positioned in the inlet end of the intake passage. Hydraulic fluid is filtered by the filter at the intake passage while it is passing through the one-way valve so that foreign particles in the hydraulic fluid from an oil reservoir are completely prevented from entering a pump seating and a pumping cylinder. Hence, the hydraulic fluid entering the pumping cylinder upon pushing of a handle on the pump seating does not contain impurities. In particular, as there are no foreign particles clogging the pressure release passage, normal pressure relief whenever the jack is overloaded can be assured to discharge the hydraulic fluid to the oil reservoir automatically. Consequently, damage to or explosion of the cylinder can be prevented.