Patent Application
20050035337
(a) Field of the Invention
The present invention relates to wheeled hydraulic jacks with a suspensory lifting means, and more particularly to a wheeled hydraulic jack with a suspensory lifting means that utilizes a vertical hydraulic unit for lifting the loading terminal of a pair of cantilever arms.
(b) Description of the Prior Art
Referring to
Accordingly, the primary objective of the present invention is to provide a wheeled hydraulic jack with a suspensory lifting means in which the hydraulic unit stands upwardly. Two movable tension links, each pivotally mounted on each of pivotal cantilever arms, have the free ends thereof connected with each end of a cross-wise shaft that goes through the piston of the hydraulic unit. The piston of the hydraulic unit moves upwardly and bears against the cross-wise shaft so as to lift the loading terminal of the pivotal cantilever arms, which defines the suspensory means. Since the hydraulic unit stands upwardly, the side plates defining the length of the jack are greatly shortened, therefore attaining a compact configuration for the jack.
The secondary objective of the present invention as a wheeled hydraulic jack with a suspensory lifting means is to provide a vertical configuration for the hydraulic unit of a jack, and thereby the piston of the hydraulic unit is not confined within the jack, which allows the installation of hydraulic units of various capacities.
It is a further objective of the present invention as a wheeled hydraulic jack with a suspensory lifting means that the hydraulic unit can be an independent module by mounting the components such as hydraulic cylinder, pump unit, oil-ejecting valve, safety valve and the associated oil tubing on a base, which base is directly mounted between the rear sections of the side plates.
Referring to
The above-mentioned wheeled hydraulic jack further comprises a main body 4, which is composed of two side plates 41. Two pairs of roller wheels 42, 43 are respectively mounted underneath the front and rear ends of the main body 4. The pivotal cantilever arms 2, bridged by a shaft sleeve 21, are pivotally mounted on the main body 4 by a shaft 44 which is inserted through the shaft sleeve 21. One or more than one connecting plates 45 are mounted between the side plates 41 on selected locations to reinforce the structural toughness of the main body 4. Further, one or more than one barricades 441 are installed on the inner wall of each side plate 41 near the lower edge thereof, for locking the hydraulic unit 1. Two pivotal links 46 are each pivotally mounted between a lifting base 22 mounted onto the loading terminal of the pivotal cantilever arms 2 and a corresponding side plate 41.
In the above-mentioned wheeled hydraulic jack, a shaft sleeve 21 is integrally mounted on a selected location at the rear portion of the pivotal cantilever arms 2. The loading terminal of the pivotal cantilever arms 2 is provided with a lifting base 22 for supporting a load. One or more than one connecting plates are mounted between the middle sections of the pivotal cantilever arms 2. The above-mentioned movable tension links 3 respectively has one end pivotally connected to the pivotal cantilever arms 2 by a dowel 31 and the other end, utilizing a hole 32 thereon, pivotally connected to the cross-wise shaft 111 of the hydraulic unit 1. As shown by the preferred embodiment, two strengthening plates 33 are each applied to a movable tension link 3, with one end mounted on the outer face of the movable tension link 3 and another end connected to the corresponding end of the shaft sleeve 21. Each movable tension link 3 is thereby pivotally sandwiched by a corresponding pivotal cantilever arm 2 and a strengthening plate 33. This measure strengthens the combination of the movable tension links 3 and the dowels 31, which prevents the deformation of the dowels 31.
The suspensory lifting means of the present invention adopts a vertical configuration for the hydraulic unit 1, which allows the freedom of installing hydraulic unit of a variety of capacities, then avoiding the problem of insufficient installation space.
The above-mentioned hydraulic unit 1 can be an independent module. That is, the components of the hydraulic unit 1, such as hydraulic cylinder 13, pump unit 14, oil-ejecting valve 15, safety valve and the associated oil tubing, can all be mounted on a base 12 which is locked at the bottom of a wheeled hydraulic jack by screwing a plurality of screws 47, through the barricades 441 on the side plates 41, to corresponding locking holes 121 formed on the base 12. The base 12 is therefore directly mounted between the rear sections the side plates 41.
This present invention utilizes a hydraulic unit 1 in a vertical configuration to form a suspensory lifting means, which is different from the conventional wheeled hydraulic jacks in that the hydraulic unit extends horizontally. The pivotal cantilever arms 2 are lifted by a suspensory driving means that may house hydraulic unit 1 of a variety of capacities. It is a further advantage that the side plates 41 are significantly shorter than those of the conventional jacks, which greatly reduces the size of a jack and simplifies the structure at the same time.
In the above-mentioned wheeled hydraulic jack, a handle seat 48 is pivotally connected to the rear portion of the space between the side plates 41. The handle seat 48, coupled with the pump unit 14 of the hydraulic unit 1, provides the insertion mechanism of a handle bar 49, which in turn drives the pump unit 14 to actuate the lifting means. This mechanism is the same as that of a wheeled hydraulic jack of the prior art.
The cross-wise shaft 111 as disclosed by the above-mentioned preferred embodiment takes the shape of a cylinder. The shaft may also have a square cross-section, being a rectangular bar 111a, or other cross-sections; this is shown from
The present invention is described by the preferred embodiments, and it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. For example, the strengthening plates 33 attached on the outer faces of the movable tension links 3 are for structural strengthening, which can be omitted. Any equivalent variation to the strengthening plates 33 is therefore allowed.
