Patent Application
20160068017
This application claims the benefit of Swedish Patent Application No. 1451035-8, filed Sep. 4, 2014. The disclosure of the above application is incorporated herein by reference in its entirety.
The invention concerns a device for lifting and positioning a wheel during wheel shifting on a vehicle, such as a car, a pick-up or the like.
Shifting wheels of a vehicle, e.g. shifting from summer to winter wheels and vice versa, may be cumbersome and involves heavy lifting and manipulation of the wheels. Typically, each wheel to be mounted needs to be lifted between 30-100 mm above the ground and then manipulated and positioned such that the mounting holes of the rim are aligned with the wheel hub. Thereafter, the wheel needs to be maintained in position while fastening the mounting screws. Especially at larger vehicles such as pick-up trucks, SUVs, cross country trucks, general purpose vehicles, jeeps and the like, where the wheels often are comparatively large and heavy, such lifting and handling of the wheels involves awkward working positions, is tiresome and may even lead to injuries to the person involved.
For this reason there have been suggested several devices intended to facilitate the lifting and positioning the wheels when carrying out wheel shifting. U.S. Pat. No. 4,050,597 A, US 2005/0254923 A1 and U.S. Pat. No. 3,850,321 A all disclose a previously known type of wheel lifting device comprising a first frame which is supported on wheels for moving and positioning the lifting device. A second frame which exhibits support means for the wheel to be lifted is arranged vertically movable relative to the first frame. A jack screw or a hydraulic or pneumatic jack is arranged between the first and second frame such that the second frame and the wheel to be lifted may easily be raised relative to the first frame and the ground. All these known lifting devices are comparatively complicated and comprise a large number of components. The devices are also comparatively large and require a great storage space when not in use. Additionally, these devices are entirely specifically designed for the purpose of lifting wheels and none of their constituent parts are intended or suitable to be used for any other purpose than lifting and positioning a wheel during wheel shifting at a vehicle.
An object of the present invention is to provide an enhanced wheel lifting device to be used when shifting wheels of a vehicle.
Another object is to provide such a device which is simple in construction and which comprises a low number of constituent parts.
A further object is to provide such a device which may easily be mounted to already existing standardized hand carts, which hand carts may be used for other purposes when not used together with the wheel lifting device.
A still further object is to provide such a lifting device which is easy to use and reliable.
Yet another purpose is to provide such a lifting device which requires only a very limited storage space, when not in use.
A still further object is to provide such a device which may readily be produced in a cost efficient manner.
These and other purposes are achieved with a wheel lifting device specified in appended claim 1. The wheel lifting device comprises a frame, a wheel support which is fixed to the frame and a manually manoeuvrable jack. The frame comprises guiding means which are arranged to receive at least two vertical bars of a two-wheeled tiltable hand cart and to guide the frame rectilinearly along said bars during vertical displacement of the frame relative to the handcart. The jack comprises an eccentric which is rotationally fixed to the frame or arranged to be rotationally fixed to the hand cart and which exhibits a peripheral support surface which is arranged bear against the hand cart or the frame respectively.
The wheel lifting device may thus be attached to and used with a conventional standardized hand cart, of the type comprising two wheels, two manoeuvring handles and a load supporting surface. An example of such a conventional hand cart is shown in
The eccentric may be rotationally fixed to the frame and the peripheral support surface may then be arranged to take support on a horizontal bar of the hand cart.
The wheel lifting device may comprise a lever which is fixed to the eccentric for manual manoeuvring of the jack.
The eccentric may comprise a circular disc provided with said peripheral support surface, which disc is rotationally fixed to the frame by means of a spindle which is arranged off-centre the disc.
The eccentric may comprise a non-circular disc provided with a curved peripheral support surface.
The disc may be rotationally fixed to the frame by means of a spindle which is arranged on-centre the disc.
Alternatively, the disc may be rotationally fixed to the frame by means of a spindle which is arranged off-centre the disc.
The difference between the largest radial distance from the peripheral support surface to the rotational axis of the disc and the smallest distance from the peripheral support surface to the rotational axis of the disc may be between 70 and 120 mm.
The guiding means may comprise a first set of guiding plates which are fixed to a front surface of the frame and a second set of guiding plates which are fixed to a rear surface of the frame and at least one set of guiding plates may be removably fixed to the frame.
The wheel support may comprise at least two rods which extend forwardly from a lower portion of the frame.
The rods may be cylindrical and provided with a respective cylindrical hollow sleeve, which sleeves are rotational about the longitudinal axes of the rods.
The frame may be formed of two mutually parallel vertical bars which are connected to each other by means of two mutually parallel horizontal bars.
The eccentric may exhibit an essentially planar end surface which is arranged in frictional contact with the frame.
The wheel lifting device may comprise means for adjusting the frictional force between the eccentric and the frame.
The wheel lifting device may further comprise a two-wheeled tiltable hand cart comprising two vertical bars and a horizontal bar, wherein the frame is arranged rectilinearly displaceable relative to the hand cart along said vertical bars.
The eccentric may be fixed to the hand cart and the peripheral support surface may then be arranged to bear against a horizontal bar of the frame.
The eccentric may exhibit an essentially planar end surface which is arranged in frictional contact with the hand cart.
The hand cart may then comprise a ground support arranged to support the hand cart in an upright position at which position the vertical bars extends in an essentially vertical direction.
Additional objects and advantages of the invention will appear from the following detailed description and from the appended claims.
Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to “a/an/the element, apparatus, component, means, step, etc.” are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The terms vertical and horizontal used herein refer to directions of the device when it is in an upstanding position such that the lifting action may be carried out in the vertical direction. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.
The invention is now described, by way of example, with reference to the accompanying drawings, in which:
The invention will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout the description. Throughout this specification, the terms vertical and horizontal refers to directions of the lifting device and the hand cart when positioned in an upright standing position such as illustrated in the figures.
As shown in
Four first brackets 2 are fixed to a front surface the frame 1. In the exemplifying embodiment shown in the figures the first brackets 2 are welded to the frame. The first brackets 2 may however also be removably fixed thereto, e.g. by means of screws or the like. After the frame 1 has been positioned at the cart 20, four second brackets 3 are fixed to the frame such that the two vertical bars 23 of the cart are received between pairs of first 2 and second 3 brackets. The fixation of the frame 1 by means of the brackets 2, 3 allows the frame 1 to be rectilinearly displaced relative to the cart, along the vertical bars 23. The second brackets 3 are shown separately, before mounting in
Two wheel supporting rods 5 are fixed to a lower end of the frame 1. The rods 5 thus form a wheel support. In the illustrated example, the rods 5 are cylindrical and extend forwardly from the frame 1, in the horizontal direction, when the cart is in an upright position. The wheel supporting rods may however also have square or similar cross sections. A cylindrical sleeve 6 is threaded onto each rod 5, such that the sleeves 6 may rotate relative to the respective rod 5. When a wheel is positioned on the rods 5 with sleeves 6, the wheel may thereby be rotated about the wheel's normal axis of rotation (see
At its upper end, the frame 1 is provided with a vertically oriented support plate 7, which is fixed to the upper horizontal frame bar 14. A shaft or spindle 8 extends generally horizontally, backwards from the support plate 7. A cylindrical cam disc or an eccentric 9 is arranged eccentrically rotational on the spindle 8. In the example shown the eccentric 9 is constituted by a circular disc formed of POM (Delrin). The eccentric may however also be formed of other polymer materials or by metal or any other suitable materials. The eccentric 9 exhibits a peripheral support surface which bears against and is supported by the upper horizontal bar 24 of the hand cart 20. A manoeuvring lever 11 with a handle 12 is fixed to the eccentric 9.
The spindle 9 and eccentric 9 are further arranged such that a first planar end surface of the eccentric 9 is in contact with and pressed against the support plate 7. For this purpose the spindle 8, which extends through the eccentric, comprises a threaded end (not shown) which protrudes backwards, away from a second end surface of the eccentric 9, which second end surface faces away from the support plate 7. A nut (not shown) is threaded onto the threaded end and arranged to press the first planar end surface of the eccentric 9 against the support plate 7. By tightening or loosening the nut it is possible to readily adjust the friction between the eccentric and the support plate. This friction may be used for maintaining the frame 1 and a wheel positioned thereon in a raised position, without the need to manually hold the lever in a corresponding position. By this means the operator may use both hands e.g. when manipulating the wheel and when fastening or loosening the fixation bolts or nuts. Since the friction between the eccentric 9 and the support plate is adjustable, it is possible to vary this friction such that it may sustain the gravitational force of wheels having varying weights. In order to maintain the selected friction for longer periods of time and a repeated use of the wheel lifting device, the nut may preferably be of the type having an elastic insert or top which prevents loosening of the nut relative to the threaded end of the spindle 8.
In
In use, the vehicle and a wheel to be shifted may first be lifted by using the vehicle's regular car jack. Typically, the car jack is fitted to the vehicle such that one wheel at the time is raised approx. 30-50 mm above the ground. Thereafter the wheel to be shifted may be loosened and removed manually. The wheel which shall replace the removed wheel is then or before positioned at the wheel supporting rods 5 with sleeves 6 as illustrated in
Naturally, the wheel lifting device may also be used when removing a wheel already mounded to a vehicle. This may be especially useful when removing heavier wheels as it reduces the risk of back injuries and other disadvantages and risks frequently occurring at manual and muscular handling of heavy and bulky wheels.
The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims. For example, at the embodiment described above, the eccentric is formed of a circular cam disc which is eccentrically arranged at a spindle. It is however also possible to form the eccentric as a non circular disc. The non circular disc may be centrically or eccentrically arranged at a spindle or other pivot means. The non circular disc may preferably have a curved peripheral support surface. The peripheral support surface may however, at some applications be provided with facet surfaces such as to provide a stepped rotation of the eccentric.
According to another alternative embodiment, which is not illustrated in the figures, the eccentric is rotationally fixed to the hand cart and arranged to lift the frame by means of the peripheral support surface bearing against a portion of the frame. E.g. the eccentric may be rotationally fixed to the hand cart by means of a spindle and a support plate similar to support plate 7 illustrated in
Further, the bars forming the hand cart has above been illustrated as having a circular cross section. It is however also possible that these bars exhibit square or rectangular cross sections. The bars may e.g. be formed of square pipes. Such an arrangement may be advantageous since welding together of such square pipes is easier than welding of circular pipes. Additionally, weld joints between square pipes are normally stronger than weld joints between circular pipes. Even further, it has proven that bending of square pipes provides for a stronger bent section, than what is achieved when bending circular pipes.
This is of certain interest since the inventor of the wheel lifting device has realized that the hand cart may be manufactured in a very cost effective manner by utilizing simple bending of square, rectangular or circular metal pipes. Such manufacturing comprises providing a metal pipe of a length corresponding essentially to the twice the height plus the width of the cart to be manufactured. The pipe is then bent a number of times such that it forms a contour corresponding to the handle portions, the vertical bars 23 and the side and front edges of the support plate 25 as seen on the hand cart illustrated in
By such a method a sturdy and reliable hand cart may be manufactured in a very cost efficient and rapid manner. The components needed may all be standardized components frequently used in the industry and being available at comparatively low costs. The bending operations for forming the hand cart base may further be carried out in a highly automated and fast manner. The formation by bending also replaces several previously used welding or corresponding joining operations, which operations are considerably more time and cost consuming than bending.
The metal pipe provided for forming the cart base by bending may preferably be of steel, such as DIN 2414. A metal pipe having a hollow circular cross section may be used. However and as indicated above, it may be preferable to use a pipe having a square or rectangular hollow cross section. The thickness of material may preferably be 1.2-2.0 mm and the square outer cross sectional dimension between 20-25 mm.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1451035-8 | Sep 2014 | SE | national |
