(a) Field of the Invention
The present invention relates to a hydraulic garage jack and more particularly, to a swiveling handle mounting mechanism of a hydraulic garage jack, which has the swiveling handle sleeve and the release valve separately installed.
(b) Description of the Prior Art
A conventional hydraulic garage jack has a fixed handle sleeve to hold an operating handle. When the user pumps the operating handle up and down, the hydraulic fluid is pumped out of the fluid chamber to the working fluid cylinder to lift the lifting arm which fits the load accordingly. Because the handle sleeve is fixedly fastened to the frame structure of the hydraulic garage jack, the operating direction of the operating handle is not adjustable.
U.S. Pat. No. 6,086,047 discloses a hydraulic jack, which has a bearing provided under the hydraulic cylinder, such that the handle may be rotated to any direction as required. According to this design, the hydraulic cylinder and the pump are arranged in the member that supports the handle, therefore the lifting stroke is short. Further, the hydraulic jack may fall sideways to the ground easily due to a short wheel base of the rear wheels.
U.S. Pat. No. 6,505,816, issued to the present inventor, discloses a jack with a swiveling handle sleeve. The handle sleeve is locked to a swiveling supporting seat. The swiveling supporting seat passes through the pump and washers to be locked to the base of the jack. Thereby, the handle sleeve may swivel rightwards and leftwards. The release valve is connected to a flexible shaft for controlling the opening and closing of the release valve. A steel ball bearing or a thrust bearing can be installed between the swiveling supporting seat or the base of the jack so that the handle sleeve may swivel freely. The handle sleeve and the swiveling supporting seat have a design for confining the lower limit. However, this design of jack is still not satisfactory in function because the handle sleeve may interfere with the release valve during swiveling.
The present invention has been accomplished under the circumstances in view. According to one aspect of the present invention, the swiveling handle mounting mechanism is mounted on the pump of the hydraulic unit of a hydraulic garage jack, comprising a seat affixed with a pressure plate to the pump beyond the release valve of the hydraulic unit, a swiveling holder horizontally rotatably coupled to the seat beneath the pressure plate, and a handle sleeve vertically pivotally connected to the swiveling holder to hold a handle for driving the pump to pump out the hydraulic fluid for lifting the load. Thus, the handle sleeve can be swiveled horizontally through 360° to move the operating handle to the desired operating direction. Further, changing the direction of the operating handle does not move the release valve accidentally, and therefore the hydraulic garage jack is safe in use.
According to another aspect of the present invention, a locking mechanism is installed in the swiveling holder at one side for locking the handle sleeve to the swiveling holder. The locking mechanism comprises a ratchet fixedly arranged around the periphery of the pressure plate, a pinhole on one upright sidewall of the swiveling holder, a lock pin inserted through the pinhole on the associating sidewall of the swiveling holder and movable relative to the swiveling holder between a locking position where the lock pin engages the ratchet to lock the handle sleeve to the swiveling holder and an unlocking position where the lock pin is disengaged from the ratchet for allowing movement of the handle sleeve relative to the swiveling holder, a spring member mounted on the lock pin and stopped between a part of the swiveling holder and one end of the lock pin to hold the lock pin in the unlocking position, and an actuating member pivoted to the upright sidewall of the swiveling holder holding the lock pin for moving the lock pin between the locking position and the unlocking position. Further, the actuating member has a finger rod extended from one end thereof for operation by hand.
According to still another aspect of the present invention, the swiveling handle mounting mechanism further comprises a pedal assembly pivoted to the swiveling holder for operation by the user to open the release valve for allowing return of the hydraulic fluid.
According to still another aspect of the present invention, the pedal assembly comprises a U-lug affixed to the hydraulic unit with a screw bolt at one side of the valve chamber, a pedal pivotally connected to the U-lug with a pivot, and a tensile spring connected between the pedal and one upright sidewall of the swiveling holder.
According to still another aspect of the present invention, a safety block is fixedly provided at one upright sidewall of the swiveling holder for supporting the pedal and stopping the pedal from operation. Therefore, the release valve is normally kept in the closed state. When the pedal is released after each operation, the tensile spring returns the pedal to its former position where the pedal is stopped above the safety block.
According to still another aspect of the present invention, the release valve is mounted with a copper washer in the valve chamber, and comprised of a release valve connecting bar, an oil return guide chamber, a first steel ball, a second steel ball, a steel ball stopper, a barrel-like compression spring, a conical compression spring, and an adjustment screw. The return oil guide chamber has a small return oil hole. When the hydraulic garage jack is bearing a load, the return flow of the hydraulic fluid goes through the small return oil hole of the oil return guide chamber so that the lifting arm is lowered slowly, ensuring high safety. When the hydraulic garage jack bears no pressure, the return flow of the hydraulic fluid goes through a big return oil hole for allowing quick return of the lifting arm.
Referring to
The seat 1 is a short, stepped cylindrical member having a center hole 14 disposed in fluid communication with the fluid chamber 102 of the pump 101 and a plurality of mounting through holes 13 fastened to the top wall of the pump 101 of the hydraulic unit 10 with screw bolts 11 and spring washers 12.
The swiveling holder 2 is a hollow frame having two upright sidewalls 22, a connecting wall 23 transversely connected between the two upright sidewalls 22 at one side, a vertically extending circular bottom hole 21 coupled to the upper small diameter part 15 of the short, stepped cylindrical seat 1, and two screw holes 221 respectively transversely formed on the two opposite upright sidewalls 22.
The handle sleeve 3 has a top barrel 31, which receives an operating handle 7, and a downwardly extending bottom U-lug 3 inserted in between the two upright sidewalls 22 of the swiveling holder 2. The bottom U-lug 32 has two pivot holes 322 and two pinholes 321 arranged at two different elevations. Two screw bolts 222 mounted with a respective washer 223 and respectively inserted through the pivot holes 322 of the U-lug 32 and respectively threaded into the screw holes 221 of the swiveling holder 2 to pivotally secure the handle sleeve 3 to the swiveling holder 2 (see
The pressure plate 4 is a flat annular member fitting the upper small diameter part 15 of the short, stepped cylindrical seat 1, having a plurality of vertical screw holes 41 respectively fastened to the mounting through holes 13 of the seat 1 and the top wall of the pump 101 of the hydraulic unit 10 by the aforesaid screw bolts 11 and spring washers 12, and a center hole 42 aimed at the center hole 14 of the seat 1 for the insertion of the plunger 5 and a return spring 52.
The plunger 5 is inserted through the return spring 52 into the fluid chamber 102 of the pump 101 and peripherally sealed (see
Based on the aforesaid arrangement, the handle sleeve 3 is pivoted to the swiveling holder 2, which is mounted in between the seat 1 and the pressure plate 4 and rotatable relative to the seat 1. Therefore, the operating handle 7 is turnable with the handle sleeve 3 relative to the seat 1 through 360 degrees. Further, because the handle sleeve 3 and the release valve 6 are separately installed, the operation of the handle sleeve 3 does not interfere with the operation of the release valve 6, providing for enhanced safety during operation.
Further, the hydraulic garage jack may be provided with a locking mechanism to lock the handle sleeve 3 in the desired angular position. According to the present preferred embodiment, the locking mechanism comprises an actuating member 81 and a lock pin 82. The pressure plate 4 has a ratchet 43 extending around the periphery. The swiveling holder 2 has a screw hole 224 and a pinhole 225 on one upright sidewall 22. A screw bolt 83 is inserted through the actuating member 81 and threaded into the screw hole 224 to pivotally secure the actuating member 81 to the swiveling holder 2. The lock pin 82 is inserted through a spring member 84 and the pinhole 225 of the swiveling holder 2 for engaging the ratchet 43. The actuating member 81 has an oblique wall 811 disposed at one end and stopped against the lock pin 82 (see
Further, as stated above, the handle sleeve 3 and the release valve 6 are separately installed. A U-lug 91 is affixed to the hydraulic unit 10 with a screw bolt 93 at one side of the valve chamber 61, which receives the sleeve valve 6. A pedal 9 is pivotally connected to the U-lug 91 with a pivot 92. A tensile spring 94 is connected between the pedal 9 and one upright sidewall 20 of the swiveling holder 2 (see
The arrangement of the aforesaid safety block 202 is to prevent accidental action of the pedal 9 in lowering the lifting arm 30 when the hydraulic garage jack is bearing the load. In the operation status shown in
Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.