Patent Application
20060151259
The present invention relates to a locking/release device particularly suitable for pushchairs and prams for young children.
During normal use of pushchairs and prams it is necessary to allow the user (by using locking/release devices constituted for example by actuation lever systems) to simply and effectively lock devices supported by the wheels, such as for example braking devices or castering devices (i.e., capable of ensuring or preventing castering motion of the wheel or set of wheels in the case of twin wheels).
Currently, devices used to lock rotation of the wheels about their own axis (braking devices) or used to prevent castering motion are generally constituted by an actuation lever that is normally pivoted to a supporting structure of the wheel or set of wheels, which supports an engagement pin that is designed to engage, if the user acts on such lever, within a seat formed on a ring that is rigidly coupled to the wheel rotation axis in the case of braking devices, or in a castering locking seat in the case of castering devices.
Although currently commercially available locking/release devices are presently widely used, they are not devoid of drawbacks.
The user, by acting on the lever to lock the device, in fact often fails to make the pin engage directly in the respective seat but makes it abut against the peripheral profile of the ring (in the case of a braking device) or of the upper edge of the support, in the case of a device for locking the castering motion.
At this point the user is in a condition in which he has to take the pressure off the lever in order to turn the wheel about its own axis or about the castering axis and try, by pressing the lever again, to insert the engagement pin within the respective seat.
It is evident that actuation of the devices described above is very awkward and laborious.
The aim of the present invention is to provide a locking/release device that is capable of eliminating or at least reducing significantly the drawback suffered by known devices.
Within this aim, an object of the invention is to provide a locking/release device that has a low production cost so as to be advantageous also from the economical standpoint.
This aim and this and other objects that will become better apparent hereinafter are achieved by a locking/release device according to the invention, particularly for pushchairs, prams or the like, comprising an actuation lever system that supports engagement means and is articulated to a supporting structure that can move with respect to at least one locking element, which has at least one abutment region and at least one engagement seat for the engagement means, the actuation lever system being mounted rotatable about a pivoting axis in order to pass from a release position, in which the engagement means are disengaged from the abutment portion, to a locking position of the locking element, in which the engagement means engage said at least one engagement seat, at least one abutment position being further provided in which the engagement means abut against at least one portion of said at least one abutment region, characterized in that it comprises elastic loading means that act between a first coupling portion that is supported by said supporting structure and the actuation lever system and are adapted to generate a thrust that acts along an axis of action that can rotate about said coupling portion, said action axis intersecting said pivoting axis in an intermediate position between the abutment position and the release position.
Advantageously, a locking/release device according to the invention has, in the abutment position, between the action axis and the pivoting axis, an arm that is adapted to generate a torque for pushing the engagement means against said at least one portion of said at least one abutment region.
Conveniently, in a locking/release device according to the invention the elastic loading means comprise a torsion spring that is coupled to the actuation lever system at a second coupling portion.
Further features and advantages of the present invention will become better apparent from the following detailed description of some currently preferred examples of embodiments, given merely by way of non-limiting example with reference to the accompanying drawings, wherein:
In the examples of embodiments that follow, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other examples of embodiments.
With reference to FIGS. 1 to 3, a locking/release device, generally designated by the reference numeral 1, according to the invention, can be associated with a braking device or brake 2.
Such locking/release device is constituted by an actuation lever system 3 that supports engagement means such as for example a pin 4.
The actuation lever system 3 is articulated to a supporting structure 5, which in turn supports the wheel or wheels, provided with at least one locking element rotationally rigidly coupled thereon; said locking element is accordingly movable with respect to the supporting structure 5.
In the example shown in
The braking ring 6 (and more generally the locking element) has at least one abutment region 7 (constituted in the illustrated example by the teeth of the braking ring 6) and at least one engagement seat 8 (constituted in this case by the gaps formed between two successive teeth).
The actuation lever system 3 is mounted rotatable about a pivoting axis 100 and is adapted to pass, under actuation by the user, from a release position (shown in
In particular, the lever system 3 may also assume an abutment position (shown in
According to the invention, elastic loading means 9, such as for example a trap spring 10, as shown in the figures, act between the supporting structure 5 and the actuation lever system 3.
In particular, the trap spring 10 is coupled, at a first substantially end portion thereof, to a first coupling portion 11 that is supported by the supporting structure 5 and, at the other opposite substantially end portion, to a second coupling or, equivalently, abutment portion 12 that is supported by the actuation lever system 3.
It is evident that the trap spring 10 (and equivalently other elastic loading means), if loaded (for example by moving the substantially end portions mutually closer) applies a force, designated by the letter F, to the actuation lever system 3, which acts along a thrust axis 101 formed by the straight line that passes through the first coupling portion 11 and through the second coupling or abutment portion 12.
As shown by the figures, the thrust axis 101 rotates about the first coupling portion 11 as a consequence of the rotation of the actuation lever system 3 about a pivoting axis 100.
The force F therefore generates a torque for the rotation of the actuation lever system 3 with respect to the pivoting axis 100 depending on an arm (b) that is generated between the thrust axis 101 and the pivoting axis 100.
It is evident, with particular reference to
According to the invention, the arrangement is such that in the abutment position (see
This allows, by turning the wheel with which the braking ring 6 is associated, the immediate transition of the actuation lever system 3 from the abutment position to the locking position without requiring the user to act on the actuation lever system 3 again.
Obviously, in order to allow the torque generated when the lever system 3 is in the abutment condition to make the pin 4 press against the abutment region 7, the balance position determined by the position of the actuation lever system 3 in which the thrust axis 101 intersects the pivoting axis 100 must be intermediate between the abutment position and the release position; in a fully equivalent manner, one can say that the abutment position must be intermediate between the balance position and the locking position.
Reverting now to FIGS. 4 to 6, a locking/release device 1 according to the invention can, in a manner that is fully equivalent to what has been described above, be associated with a castering device 20, which comprises a supporting structure 5 and is rotationally coupled to a supporting bush 21 (which in this application forms the locking element at its edge that is arranged upward during use).
Therefore, at the edge of the supporting bush 21 that is arranged upward during use there is an abutment region 22 and there is a seat 23, in this case for locking the castering motion, in which, in the locking position (shown in
In this different case also, the pivoting axis 100 and the thrust axis 101 must be arranged so that the balance position (in which the thrust axis 101 and the pivoting axis 100 intersect) is intermediate between the abutment position (in this variation shown in
As clearly shown in
Furthermore a second arm protrudes from each of the two spiral coils 10a: an abutment element 10c is provided between the end portions of the second arms, and in addition to connecting the two second arms it is adapted to abut, during use, against the second engagement or abutment portion 12 supported by the actuation lever system 3.
It has been shown that a locking/release device for pushchairs, prams or the like, according to the invention, fully achieves the intended aim and object.
All the details may further be replaced with other technically equivalent elements.
In particular, the elastic loading means can be constituted also by an axial spring that is optionally pre-compressed: in this case, it is convenient to review the arrangement of the pivoting axis 101 and of the first and second coupling portions 11 and 12.
The materials and the dimensions may be any according to requirements.
The disclosures in Italian Utility Model Application No. VR2003U000004 from which this application claims priority are incorporated herein by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| VR2003U000004 | Feb 2003 | IT | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP03/14711 | 12/22/2003 | WO | 8/3/2005 |
