EP0620181A1

EP0620181A1 - Compact jack

Info

Publication number: EP0620181A1
Application number: EP93106024A
Authority: EP
Inventors: Clemente Pavanello
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-04-14
Filing date: 1993-04-14
Publication date: 1994-10-19

Abstract

A jack, particularly to be used for lifting motor vehicles, which comprises a jack body made of sheet metal which includes a plurality of arms (2,3,4,5), made of sheet metal, which are mutually engaged in an articulated manner and can be actuated so as to open and close by virtue of a screw-like element (10) which is generally engaged with the jack body, one arm (5) being rigidly coupled to a first substantially plate-like supporting element (12) for resting on the ground, another arm (2) being rigidly coupled to a second block-like supporting element (15) which can engage the lower surface of the floor pan of the motor vehicle. Actuation means (11) are provided to produce the reversible rotation of the screw-like element (10). A reduction unit (16) is included between the actuation means (11) and one end of the screw-like element (10) and is suitable to reduce, according to a preset reduction ratio, the actuation transmission between the actuation means (11) and the screw-like element (10).

Description

The present invention relates to a compact jack, particularly to be used for lifting motor vehicles.
Many jacks to be used for lifting motor vehicles are already commercially available; however, they are not free from drawbacks.
One of these is the lack of compactness and solidity of the jack.
The aim of the invention is to substantially eliminate this drawback by providing a jack which is extremely compact and at the same time sturdy and reliable in operation.
Within the scope of this aim, an object of the present invention is to provide a compact jack in which actuation is facilitated, in that it can be opened and closed, while the weight of the vehicle bears on it, with a minimal effort and which, at the same time, ensures a condition of perfect stability and balance of the lifted motor vehicle, during both lifting and lowering.
Another object of the present invention is to provide a compact jack which can be easily adapted for automatic actuation.
Another object of the present invention is to provide a jack which is extremely competitive from a purely economical point of view.
Another object of the present invention is to provide a jack which can be easily manufactured starting from commonly commercially available elements and materials.
According to the present invention, the above aim and objects and others which will become apparent hereinafter are achieved by a jack, particularly to be used for lifting motor vehicles as defined in the appended claims.
Further advantages and particularities of the compact jack, particularly to be used for lifting motor vehicles, according to the present invention, will become apparent from the following detailed description of currently preferred embodiments thereof, illustrated only by way of non-limitative example in the accompanying drawings, wherein:

figure 1 is a partially cutout schematic front elevation view of a first embodiment of the jack according to the invention, in its active or erected position;
figure 2 is schematic front elevation view of the jack of figure 1 in its inactive or folded position;
figure 3 is a front elevation view of the jack of the preceding figures in its active position, with an electric actuation motor applied thereto;
figure 4 is a plan view of the jack of the preceding figures in its inactive position;
figure 5 is a schematic front view of a second embodiment of the jack according to the invention, in its active position;
figure 6 is a schematic side view of the jack of figure 5, in its active position;
figure 7 is a perspective detail view of arm elements of the jack of figures 5 and 6;
figure 8 is a front view of the jack of figure 5 in its inactive position;
figure 9 is a top plan view of the jack of figure 5, in its inactive position;
figure 10 is a schematic front view of a third possible embodiment of the jack according to the invention, in its active position;
figure 11 is a schematic side view of the jack of figure 10 in its active position;
figure 12 is a perspective detail view of a locking assembly associated with the jack of figure 11; and
figures 13 and 14 are respectively a front view and a top plan view of the jack of figure 10, in its folded or inactive position.

With reference to the accompanying drawings and more specifically to figures 1 to 4, said figures illustrate a first currently preferred embodiment of the jack according to the invention.
More specifically, with reference to figure 1, in this figure the jack of this embodiment of the invention has been generally designated by the reference numeral 1.
Said jack, as can be seen, is substantially of the pantograph type and comprises four mutually articulated arms designated by the reference numerals 2, 3, 4 and 5. The arms 3 and 4 are articulated at one of their ends by pivot means 6, and the arms 2 and 5 are articulated at one of their ends by an articulation pivot 7.
The arm 3 is articulated to the arm 2 by means of the pivot 8, and the arm 4 is articulated to the arm 5 by means of the pivot 9; the described arms are conventionally obtained for example by pressing metallic material in sheet form.
The two pairs of arms 3-4 and 2-5 are mutually joined, at a respective end, by means of a screw-like actuation element 10 which is rotatably actuated, in a conventional manner, in both directions by means of a substantially L-shaped actuation crank 11.
The arm 5 is rigidly coupled, in a downward region, with a plate-like element 12 for resting on the ground, which has grip studs 14, whereas the arm 2 is rigidly coupled to a block 15 which is positionable for abutment against the underside of the floor pan or support member of a motor vehicle (not shown) to lift it and/or lower it.
So far, the described jack is substantially conventional.
According to the present invention, a reduction unit, generally designated by the reference numeral 16, is interposed between the actuation handle 11 and the screw-like actuation element 10; in particular, said unit 16 may be of any known type, for example of the type with gears or with a toothed belt and toothed sprockets for actuation, as schematically shown in figure 1 by dashed lines.
In this manner, a preset reduction ratio is produced between the actuation handle 11 and the screw-like element, so that the actuation handle 11 can be made extremely compact and easily adaptable to the body of the jack in its closure position.
Practical tests have allowed to determine that an advantageous reduction ratio for the unit 16 is 50%.
According to a further aspect of the invention, the arm 5 is pivoted at 17 to the plate-like element 12 for resting on the ground; this pivoting facilitates the jack in assuming a position of substantially stable equilibrium when the motor vehicle is lifted and lowered. In figure 2, the jack according to this embodiment is shown in its closed position, with the handle still extracted, whereas in figure 4 the handle 11 has been folded against the jack body by rotating said handle about its articulation point 20. It can be seen, especially from figures 2 and 4, that the jack is extremely compact.
It can also be seen that the reduction unit 16 is also structurally extremely simple and that it can be easily adapted to the jack body by virtue of any convenient coupling means. In figure 3, the use of a direct-current motor 21 has been provided for instead of the actuation handle 11; said motor is powered by the motor vehicle battery (not shown) by means of a power supply cable 22 which is shown in a cutout view; the coupling between the motor 21 and the reduction unit 16 may be of the removable plug-in type and can in any case be obtained by virtue of any coupling means known to the expert in the field.
With reference now to figures 5 to 9, said figures show a second embodiment of the jack according to the invention, which is also of the pantograph type with articulated arms; said jack is again generally designated by the reference numeral 1. This embodiment differs substantially from the preceding embodiment in that although the respective ends of the arms 2', 3', 4' and 5' are articulated so that they can oscillate by means of pivots 6' and 7', the other respective ends of said arms are mutually engaged, so that they can oscillate, by means of a substantially "toothed" profile.
In particular, the upper toothed profiles 3'' and 2'' of the arms 3' and 2' respectively, and the lower toothed profiles 4'' and 5'' of the arms 4' and 5' respectively, have been provided, according to yet another aspect of the invention, with particular strength characteristics by virtue of an outward fold of the metallic material in sheet form which constitutes said engaged portions of said arms.
Figure 5 also shows that the two arms 4' and 5' are substantially rotatably articulated, at 17' and 17'', to the usual plate-like element 12' for resting on the ground.
In this case, too, the two arms are operatively joined by means of the screw-like actuation element 10'.
According to the invention, the reduction unit, generally designated by the reference numeral 16', has been applied to this jack configuration as well; as in the case of the previous embodiment, it can be of the type with gears or with a toothed belt and toothed sprockets, which can also be actuated manually, by means of the handle 11', or by means of a motor which is not specifically shown herein.
Figure 7 is a detail view of the two lower arms 4' and 5', which are substantially C-shaped and the lower profiles of which have reinforced teeth.
In figure 6, the jack according to this embodiment, which is shown in its active or open position, clearly shows the oscillated but substantially balanced position assumed by the jack, which is loaded in the direction indicated by the arrow by the motor vehicle, which is not shown; this position can be easily assumed by virtue of the articulated or jointed top and base connection of the jack body.
Thus, in addition to being easy to actuate, the jack according to this embodiment of the invention is also capable of ensuring a position of absolutely stable equilibrium during all steps of the lifting and lowering of the motor vehicle.
Finally, with reference to figures 10 to 14, said figures show a further possible embodiment of the jack which is the subject of the improvements according to the invention.
In this case, the jack, generally designated by the reference numeral 100, substantially comprises a jack body constituted by two arms which are made of sheet metal, are also for example generally C-shaped, and are respectively designated by the reference numerals 200 and 500.
As can be seen, the two arms 200 and 500 are mutually rotatably articulated at 900; they are also mutually connected by means of a screw-like actuation element 1000, an end of which is coupled to the reduction unit 1600 which again constitutes a peculiar aspect of the invention.
The free end of the arm 200 is rotatably coupled to the block 150 which is provided for engagement with the lower surface of the floor pan of the motor vehicle, whereas the lower end of the arm 500 is oscillatably coupled at 170, to the plate-like element 120 for resting on the ground. In this case, the actuation crank 110 is provided for the actuation of the reduction unit 1600.
According to a further aspect of this embodiment of the invention, said jack has been further improved by providing improved means for coupling between the actuation screw 1000 and the arm 200 of the jack.
More specifically, with reference to figure 12, the arm 200, which is substantially C-shaped, comprises a slot 220 which is provided so that it can be crossed by the screw 1000 during the extension of the jack.
The left end of the actuation screw 1000 (as shown in figures 10 and 12), i.e. the end which is not coupled to the actuation assembly-reduction unit 1600, is rotatably engaged in a nut-like block 190 which is provided with an internal thread 191 and can be engaged in a removable manner in two holes 192 and 193 which are respectively formed in the walls of the substantially C-shaped arm 200.
Said holes 192 and 193 are advantageously provided with portions folded so as to form flaps 194 and 195 respectively for the removable locking of the block 190 to the arm 200; said locking is completed by applying two external plug-like closure elements, respectively 198 and 199, to the block, as more clearly shown in figure 12.
In this manner, by virtue of the described locking system or assembly, the actuation screw 1000 can be locked in an extremely reliable manner to the arm 200, and the actuation movement of the screw 1000 can be easily obtained by virtue of the crank 110, or of the electric motor, if desired, ensuring in any condition the virtually complete elimination of flexural stresses on said screw, by virtue of the locking assembly in which it is engaged, thus substantially improving the operating reliability and the sturdiness of this embodiment of the jack.
In figure 11, the jack is shown in its active position, with its lower and upper ends swung into a position of extremely stable equilibrium, whereas in figures 13 and 14 the jack is shown in its folded position, and figure 14 in particular, in which the lever 110 has been folded against the jack body, shows that the jack has an extremely compact configuration in this case as well.
From the above it can be seen that the compact jack according to the invention fully achieves the intended aim and objects.
Although the jack according to the invention has been described with specific reference to currently preferred embodiments thereof, one should bear in mind that the described embodiments are susceptible to numerous modifications and variations, all of which are within the scope of the inventive concept.
For example, the elements for mutually coupling the various elements that constitute the invention, as well as the contingent shapes and dimensions, may be any according to the requirements.
Therefore, the scope of the invention must be understood as being defined, rather than by the preceding illustrations, by the spirit and the protective scope of the following claims.
Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the scope of each element identified by way of example by such reference signs.

Claims

Jack particularly to be used for lifting motor vehicles, which comprises a jack body made of sheet metal which includes a plurality of arms, made of sheet metal, which are mutually engaged in an articulated manner and can be actuated so as to open and close by virtue of a screw-like element which is generally engaged with said jack body, one of said arms being rigidly coupled to a first substantially plate-like supporting element for resting on the ground, another one of said arms being rigidly coupled to a second block-like supporting element which can engage the lower surface of the floor pan of the motor vehicle, actuation means being provided to produce the reversible rotation of said screw-like element; characterized in that a reduction unit is provided between said actuation means and the actuation end of said screw-like element and is suitable to reduce, according to a preset reduction ratio, the actuation transmission between said actuation means and said screw-like element.
Jack according to claim 1, characterized in that said reduction unit is a reduction unit of the type with gears.
Jack according to claim 1, characterized in that said reduction unit is a reduction unit of the type with a toothed belt and toothed sprockets.
Jack according to any one of the preceding claims, characterized in that said preset reduction ratio is substantially 50%.
Jack according to any one of the preceding claims, characterized in that said arm is rigidly rotationally coupled to said first substantially plate-like supporting element for resting on the ground.
Jack according to any one of the preceding claims, characterized in that said further arm is rigidly rotationally coupled to said block-like supporting element which can engage the lower surface of the floor pan of the motor vehicle.
Jack according to any one of the preceding claims, characterized in that some of said arms are oscillatably engaged at their respective ends by virtue of means with a reinforced toothed profile which is obtained by folding the metallic sheet material of some of said arms at their engagement end portions.
Jack according to any one of the preceding claims, characterized in that the end of said screw-like element which is opposite to its end engaged by said actuation means is associated with a block and rotatably supported thereby; said block being internally threaded and rigidly coupled to one of said arms.
Jack according to claim 1, characterized in that said actuation means comprise a manual actuation lever which is substantially L-shaped.
Jack according to claim 1, characterized in that said actuation means comprise means with a direct-current electric motor which is suitable to be powered by the battery of said motor vehicle and can be coupled to said reduction unit in a removable manner.