The present invention will now be described in detail, purely by way of a non-limiting example, with reference to the accompanying drawings, in which:
In the following description and accompanying drawings, only the part of the buckle containing the innovative lock mechanism is described and illustrated. For any other details, the reader is referred to the known art referred to in the introduction.
With reference to
Two known tongues 20 and 21 are insertable inside body 12 through an opening 14 in front wall 12d and in a direction substantially perpendicular to front wall 12d (hereinafter referred to as the longitudinal direction).
Tongues 20 and 21 are attached respectively to a second and third strap portion (not shown) by means of respective slots 22 and 23, and each comprise, in known manner, a stem portion 24, 25 having a downward-facing recess 26, 27 which acts as a retaining seat. As will be clear from the following description, a buckle in accordance with the invention may obviously also be used in retaining systems employing a different number of tongues (typically one or three).
Hollow body 12 houses the buckle click-on lock mechanism, which substantially comprises a rodlike retaining member 28 and a release button 29, both shown in detail in
With particular reference to
Retaining member 28 also comprises two guide members 31 and 32 fixed to the ends of rod 30, and which slide, in a direction perpendicular to the plane of bottom wall 12a (hereinafter referred to as the vertical direction), inside an appropriately shaped guide seat 34 formed in body 12. Alternatively, one guide member—in this case, annular in shape—may be provided.
The two guide members 31, 32 (or one guide member) are preferably made of plastic material. Rod 30 may be made of plastic material—in which case, it is formed in one piece with guide members 31 and 32—or of metal material—in which case, the two guide members are advantageously molded onto it.
Retaining member 28 is movable, in the vertical direction defined above, between a lowered position, in which tongues 20 and 21 can be inserted and released inside body 12, and a raised position (shown in
Retaining member 28 is maintained in the raised lock position by a spring 35—in the example shown, a leaf spring, the ends of which press on guide members 31 and 32, on one side, and the central portion of which presses on bottom wall 12a of body 12, on the other side.
Spring 35 may obviously be a different type, e.g. a helical compression spring; in which case, two springs are preferably used, and press on the two guide members 31 and 32 at the ends of rod 30.
Button 29 comprises, in known manner, a top portion 36, e.g. disk-shaped, which is pressed by the user to release the strap; and two guide members 38 and 39 joined to (e.g. formed in one piece with) top portion 36 and mounted to slide inside guide seat 34.
The two guide members 38, 39 of button 29 advantageously comprise respective stop teeth 40, 41, which slide in respective vertical grooves 42, 43 (
Button 29 is maintained in the lock position by a spring 46—in the example shown, in the form of a cylindrical helical spring—interposed between disk-shaped portion 36 and a supporting surface 48 (shown schematically in
Operation of the lock mechanism of the buckle according to the invention will now be described briefly.
When inserted inside buckle body 12 at the lock stage, tongues 20, 21 interact in known manner with rod 30 of retaining member 28, so that rod 30 engages retaining seats 26, 27 on the tongues to retain the tongues inside the buckle. Retaining member 28 being a separate component part from button 29, the button remains stationary in the lock position during the above operation, thus generating no noise. When button 29 is pressed at the release stage, on the other hand, guide members 38, 39 of the button push retaining member 28 into the lowered position, in which rod 30 disengages the retaining seats on the tongues, which are expelled in known manner from buckle body 12 by an ejector spring 50 (shown in
The second embodiment substantially differs from the first by the rodlike retaining member only comprising rod 30, with no guide members. The ends of rod 30 slide inside respective guide seats 52 formed in hollow body 20 beneath guide seat 34 of button 29. Rod 30 is moved downwards, to release the lock mechanism, by two bottom appendixes 54 (only one shown in
The third embodiment substantially differs from the second by retaining rod 30 sliding inside two guide seats 56, 57 defined by slots in respective guide members 38, 39 of release button 29.
In the second and third embodiment too, spring 35 acting on retaining rod 30 may be a leaf spring or any other suitable type. For example, two cylindrical helical springs pressing on the two ends of the rod may be used.
The fourth embodiment differs from the
Body 12 is also formed by molding plastic material onto a metal reinforcing insert 65 (shown partly).
Metal insert 65 is embedded completely in the plastic material, and comprises : an annular end portion 66 embedded in portion 16 about slot 18; a load-transfer portion 67 defined by two arms (only one shown) and extending, from portion 66, along lateral walls 12c and beneath guide seats 52 (not shown in
Clearly, changes may be made to the embodiments and details described and illustrated herein purely by way of non-limiting examples, without, however, departing from the scope of the invention as defined in the accompanying Claims.