Abstract: One jack stand includes a stand assembly having a base and a tubular receiving member extending upwardly therefrom. A latch extends from the tubular member. A support bar having upper and lower ends is telescopically housed in a cavity of the tubular member. First and second sides of the bar each have multiple embedded slots. A third side of the bar has multiple holes with angled surfaces such that positioning the latch in any of the holes restricts the bar from moving upwardly yet allows the bar to move downwardly. An automatic lifting device is at least partially inside the cavity and imparts an upward force upon the bar. A stopper selectively interacts with the stand assembly and the bar to restrict the bar from moving downwardly, yet allows the bar to move upwardly. The stopper passes at least partially inside two of the slots to interact with the bar.

Abstract: One jack stand includes a stand assembly having a base and a tubular receiving member extending upwardly therefrom. A latch extends from the tubular member. A support bar having upper and lower ends is telescopically housed in a cavity of the tubular member. First and second sides of the bar each have multiple embedded slots. A third side of the bar has multiple holes with angled surfaces such that positioning the latch in any of the holes restricts the bar from moving upwardly yet allows the bar to move downwardly. An automatic lifting device is at least partially inside the cavity and imparts an upward force upon the bar. A stopper selectively interacts with the stand assembly and the bar to restrict the bar from moving downwardly, yet allows the bar to move upwardly. The stopper passes at least partially inside two of the slots to interact with the bar.

Abstract: The disclosed subject matter provides a warning system for overloads in hydraulic jacking and lifting structures, that provides a warning to the user sufficiently prior to an actual overload condition. The overload or potential overload is detected from fluid pressures of the fluid displaced from the pump of the jacking or lifting structures.

Abstract: A ventilation valve of a hydraulic jack is dedicated to be mounted at an outer wall of an oil storage tank of a hydraulic jack. The hydraulic jack includes a valve seat, a valve ball, and a cap. When the jack is not operated, a valve hole is opened; the vent of the cap is communicated with the oil storage tank of the jack so as to maintain the equilibrium of the pressure of the oil storage tank; thereby the piston of the pump can suck oil successfully so that the oil is absorbed into the oil chamber of the pump to be saturated therein. At the moment that the valve ball ejects upwards rapidly, the oil buffer chamber can buffer high pressure draining oil until the oil return operation of the jack is accomplished.

Abstract: A jack having a detachable rear-end handle comprises a wheeled jack and a hand-held ring. Two sidewalls of the jack are each provided with a pair of blocking pieces respectively mounted on an upper location and a lower location about a screw nut of a rear shaft. The hand-held ring can be coupled to screw nuts of a rear shaft. The blocking pieces further restrict the rotation of the hand-held ring. The connection of the hand-held ring at the rear end of the jack not only facilitates carrying the jack but also controlling the movements of the jack to a proper lift point.

Abstract: A jack having a detachable rear-end handle comprises a wheeled jack and a hand-held ring. Two sidewalls of the jack are each provided with a pair of blocking pieces respectively mounted on an upper location and a lower location about a screw nut of a rear shaft. The hand-held ring can be coupled to screw nuts of a rear shaft. The blocking pieces further restrict the rotation of the hand-held ring. The connection of the hand-held ring at the rear end of the jack not only facilitates carrying the jack but also controlling the movements of the jack to a proper lift point.

Abstract: An air compressor with shock-absorption rubber strips at a bottom thereof, wherein the air compressor has an air compressor. At least one shock-absorption rubber strip is installed to the air compressor bottom plate; the shock-absorption rubber strip is firmly secured to the air compressor bottom plate. The shock-absorption rubber strip is installed with a plurality of elastic foot pad so that when the air compressor is actuated, the elastic foot pad will absorb the shock of a casing of the air compressor.

Abstract: A hydraulic lifting device capable of being rapidly raised in a mechanical movement by use of a linkage mechanism that comprises a lifting device, a rotating shaft and a linkage. The lifting device has a basic construction of two vertical side plates, a lifting arm, and a saddle support plate at the front end of the lifting arm. An outer end of the saddle support plate has an axial rod at a predetermined position. The rotating shaft extends through a clearance hole in the vertical side plate of the lifting device. The rotating shaft is integrally attached to the linkage, and the linkage has two extreme ends which are integrally attached to both the rotating shaft and the axial rod in the saddle support arm.

Abstract: A ventilation valve of a hydraulic jack is dedicated to be mounted at an outer wall of an oil storage tank of a hydraulic jack. The hydraulic jack includes a valve seat, a valve ball, and a cap. When the jack is not operated, a valve hole is opened; the vent of the cap is communicated with the oil storage tank of the jack so as to maintain the equilibrium of the pressure of the oil storage tank; thereby the piston of the pump can suck oil successfully so that the oil is absorbed into the oil chamber of the pump to be saturated therein. At the moment that the valve ball ejects upwards rapidly, the oil buffer chamber can buffer high pressure draining oil until the oil return operation of the jack is accomplished.

Abstract: A vibration and displacement-proof air compressor has an air compressor. A bottom plate of the air compressor is installed with at least one elastic leg pad. An upper portion of the elastic leg pad is firmly secured to the bottom plate of the air compressor so that when actuating the air compressor, the elastic leg pad absorbs the vibration of the air compressor so that no displacement occurs.

Abstract: An air compressor with shock-absorption rubber strips at a bottom thereof, wherein the air compressor has an air compressor. At least one shock-absorption rubber strip is installed to the air compressor bottom plate; the shock-absorption rubber strip is firmly secured to the air compressor bottom plate. The shock-absorption rubber strip is installed with a plurality of elastic foot pad so that when the air compressor is actuated, the elastic foot pad will absorb the shock of a casing of the air compressor.

Abstract: A car waxing machine with a driving handle comprises a car waxing machine and two pivotal handles. Each pivotal handle is a rod shape arm. The arm has a bent structure. Thereby, a rear section of the pivotal handle has a pivotal end and a front end thereof has an arm. By the arms of the two pivotal handles to be pivotally connected to two sides at the rear end of the car waxing machine, a structure with two arms at two sides which is rotatable for adjust the orientations of the arm is formed. Thereby, the arms are adjustable to horizontally extend to the two sides of the car waxing machine. Therefore, the user may adjust the arms to match the habits of using a car waxing machine and further forces can be uniformly applied to the machine.

Abstract: A support seat of a manual pump oil cylinder includes an oil cylinder, a handle and a transparent support seat. A distal end of the oil cylinder is locked by the transparent support seat. The oil cylinder is locked between the transparent support seat and the front seat by the fixing shaft. The handle is pivotally combined to the front seat. The transparent support seat is locked to a distal end of the supporting seat. Part or whole of the transparent support seat is made of transparent material. The transparent support seat is made with a middle hole and an annular trench. A cup-like nut and an annular oil seal are locked to a distal end of the oil cylinder. The transparent support seat is sealed and locked to a bottom of the oil cylinder. By the transparent support seat, the user can check the amount of oil directly.