The invention relates to a trolley jack of the type that aids in lifting vehicles or other heavy objects and is widely used in vehicle workshops.
More specifically, the trolley jack of the present invention is of the type having an operating lever that can be lowered such that it can be folded when it is not operative, minimizing the space it occupies.
Trolley jacks are apparatus widely used in vehicle workshops or in other places where mechanical works for lifting heavy objects are performed.
Such jacks generally comprise a main body with respect to which there is arranged in a movable manner some type of lifting element which, when duly operated by means of a hydraulic system or the like, is capable of moving up, exerting enough force under the vehicle or heavy object for lifting same, as well as means allowing the controlled downward movement of said lifting element in order to prevent imbalance that may cause accidents when the lifting element is moved downward under load.
On the other hand, these jacks usually have an operating lever allowing the user to actuate the hydraulic system or the like and to subsequently move the lifting element up.
Said lever usually consists of a telescopic or non-telescopic arm of a considerable length which projects upwards in an operative position to provide the user with a comfortable grip zone that the user can pull on if he/she only wants to move the jack on its wheels or operate it to actuate the lifting mechanism when lifting a vehicle.
This, however, means that such jacks occupy a large amount of space when not in use, so they may be uncomfortable or even become a nuisance if the workshop space or the place in which the jacks are located is small.
To prevent this drawback, there were some jacks in which said lever pivots at its lower end so that it can folded on the main body of the jack, making jack storage easier as it occupies far less space.
However, the mechanism that enables said lever to pivot so that it can be lowered has the drawback of being completely manual, requiring an operator with certain skill. Therefore, some systems are known in which in order to produce said lowering, said lever must first be pulled up a certain length in order to bring it out of an interlocking point, at which time it can already be lowered.
This discomfort is combined with the fact that the same interlocking point which allows lowering the lever is sometimes also the point on which said lever must rotate or turn in order to operate the means allowing the controlled downward movement of the lifting element, so lowering the lever may cause the unwanted downward movement of said lifting element or vice versa, i.e., accidentally lowering said lever when trying to cause the downward movement of the lifting element.
Therefore, more experiment and practice in handling is still necessary in these last cases if involuntary movements that can delay the operations or, in the worst case, cause an accident, are to be prevented.
The trolley jack object of the present invention solves the drawbacks of the state of the art mentioned above insofar as it allows lowering the operating lever easily without risk for the load or for the operator.
Specifically, the jack of the invention comprises interlocking means which allow fixing the operating lever in the operative position thereof so that the user can move the lifting element up.
On the other hand, the jack of the invention comprises automatic release means which, when operated, release the operating lever, which can then be easily and readily lowered without the user having to make any effort and making said lowering independent from the movement causing the controlled downward movement of the lifting element, preventing errors and allowing handling by an operator without said operator having a lot of previous experience.
More specifically, the trolley jack of the invention comprises a main body with a lifting element that is capable of moving up or down with respect to said main body through the action of the operating lever. To that end, said main body comprises in its rear part, opposite said lifting element, a lever holder to which the lower end of said operating lever is fixed and which activates the hydraulic mechanism responsible for causing the lifting element to move up.
Said lever holder comprises the interlocking means and automatic release means which allow retaining or releasing the operating lever, respectively, in order to provide two possible modes of operation, i.e.:
To complement the description that is being made and for the purpose of aiding to better understand the features of the invention according to a preferred practical embodiment thereof, a set of drawings is attached as an integral part of said description in which the following is depicted with an illustrative and non-limiting character:
In view of the described drawings, it can be seen how the trolley jack of the invention comprises a main body (1) with a lifting element (2) that is capable of moving up or down with respect to said main body, which lifting element (2) is operated by the user through an operating lever (3) which, as can be seen in
More precisely,
As explained above, the jack comprises both interlocking means which allow fixing the operating lever (3) in the operative position thereof so that the user can actuate the lifting element (2), and automatic release means for automatically releasing said operating lever (3) which allow lowering same if it will not be used.
To that end and as can be seen in the drawings, particularly in
More specifically and as shown in
On the other hand, at the upper end of said lever holder (7) there is housed a latch (9) which is capable of moving longitudinally along the inside thereof from a lower position in which it abuts with the upper end of the elongated body (15) to an upper position in which it protrudes partially through the upper edge of the lever holder (7), upper position in which, when the operating lever (3) is raised, i.e., in the not lowered operative phase and therefore interlocked with the lever holder, the latch (9) is partially introduced in a cavity (10) which the operating lever (3) has at its lower end (8), causing the interlocking between operating lever (3) and lever holder (7) such that the user can, by operating the operating lever (3), move said lever holder (7) and, integrally and simultaneously, move the elongated body (15) responsible for operating the hydraulic mechanism causing the lifting element (2) to move up.
On the other hand, the latch (9) can also be in the same position, i.e., in the upper position in which it protrudes partially through the upper edge of the lever holder (7) when the operating lever (3) is lowered, as can be seen in
That position in which the latch (9) protrudes through the upper edge of the lever holder (7) is the stand-by position as a result of the action of a spring-type elastic element (14) or the like keeping said latch (9) separated from the elongated body (15) as it is located between both as seen in
Therefore, starting from the position in which the latch (9) is in the stand-by position, i.e., protruding partially through the upper edge of the lever holder (7) when the operating lever (3) is raised and in a not lowered operative phase and therefore interlocked with the lever holder, if the user wants to fold the jack by lowering the operating lever (3), he/she must overcome the resistance of the elastic element (14) to allow said latch (9) to retract or move down the lever holder (7) and out of the cavity (10) which the operating lever (3) has at its lower end (8).
To that end, the jack of the present invention comprises a push element (12) integrally attached to the latch (9) by means of a screw (13) or the like which, when being operated, overcomes the resistance of the elastic element (14) and pushes the latch (9) in a direction such that it moves down to the lower part of the lever holder (7).
According to the embodiment shown in the drawings, said push element (12) is located in the rear lower part of the main body (1) of the jack, such that it can be comfortably operated by the user with hands or with feet while working, however, the possibility of operating the push element from the handle (4) of the operating lever through an intermediate operating system is not dismissed.
In contrast, starting from the position in which the operating lever (3) is lowered on the main body (1), if the user wants to place it in a vertical position to interlock it with the lever holder (7) and to thus change to the operative position, he/she will raise said operating lever (3) to the point at which the upper corner (11) of the latch (9) contacts the edge (11′) of the lower end (8) of the operating lever (3), at which time he/she must exert a certain force in order to overcome the friction between both, as well as the resistance of the elastic element (14) such that he/she causes said latch (9) to move down along the lever holder (7) until, the operating lever (3) being put in place such that its longitudinal axis coincides with the longitudinal axis of said lever holder (7), the latch (9) is introduced in the cavity (10) driven by the elastic element (14) and changing to the interlocking position described above.
According to a possible embodiment of the invention shown in the drawings, both the upper corner (11) of the latch (9) and the edge (11′) of the lower end (8) of the operating lever (3) are rounded in order to reduce the friction between both and therefore to also overcome the resistance of the elastic element (14) more easily. Nevertheless, when the operating lever (3) is to be interlocked with the lever holder (7) as described, the user can always operate the push element to overcome the resistance of the elastic element (14) and push the latch (9) in a direction such that it moves down to the lower part of the lever holder (7) instead of interlocking, overcoming the friction between the upper corner (11) of the latch (9) and the edge (11′) of the lower end (8) of the lever as explained.
According to also a possible embodiment shown in the drawings, the trolley jack comprises at least one securing element (6) for fixing the operating lever (3) when it is lowered with respect to the main body (1). According to a possible embodiment, said securing element (6) is connected in an articulated manner to said operating lever (3) at one of the ends thereof whereas the other end in the shape of a hook or the like, is secured to the axle of the wheels or rolling elements (5), as shown in
The presence of this securing element (6) prevents unwanted decoupling of the operating lever (3), which makes handling the jack easier and increases user safety. Furthermore, if the jack is lightweight enough, it allows the user to hold it by the operating lever (3) itself and transport it with his/her bare hands, which in some occasions may be preferable than transporting same by moving it with the help of the wheels or rolling elements (5).
Finally, according to another possible embodiment, the operating lever (3) is telescopic so that its length is variable and can be adapted or adjusted both to the height of the user and to the length of the main body (1) when it is lowered thereon, preventing it from protruding and making the assembly more compact and reducing storage space.
Number | Date | Country | Kind |
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14382363.1 | Sep 2014 | EP | regional |