FR2801535A1 - Wheels blocking mechanism for shopping trolley has vertical pivoting axis rotating around the wheel axis and the locking zone of the platform cooperating with a slot of the frame when the weight reaches a threshold - Google Patents

Abstract

Wheel (1) has axis (2) in bracket (3) forming a platform (5) which has a pivoting zone (12) and a locking zone (13). When the trolley reaches a certain weight, the vertical pivoting axis (7) rotates around the wheel axis and the locking zone of the platform cooperates with a slot (14) of the frame (8) .

Description

 The invention relates to a device for securing the tidirectional rollers by blocking the orientation of the swivel caster about a vertical axis under the effect of the load that it supports.

When shopping in shopping centers, it is useful to have a truck with four wheels that are multi-recalibrated so that it can be moved with a manual maneuver all the directi these wheels are placed symmetrically two to two to the plane of longitudinal symmetry of the chassis of the trolley, and two of them constitute the nose gear and the two others, located on the side of the bar of manual maneuver constitute the train back.

The shopping malls ground is generally horizontal in all areas sheltered from the rain, but outside the covered areas, it is necessary to provide a slope to promote the flow of rainwater; number of car parks follow, either the natural slope of the land or have horizontal parking areas forming terraces connected by steep tracks. When the truck is equipped with four multidirectional wheels, it is naturally driven in the line of greatest slope; if the direction in which one wants to go is different, the slope of the biggest slope, it is difficult to hold it, and this is all the more difficult as the truck is heavily loaded.

Figure 1 shows in elevation of a conventional multi-directional wheel equipped with a rotation locking device according to the invention in the unlocked position and shown in section. Figure 2 shows a section of the blocking device of Figure 1, seen from above, A A '.

Figure 3 shows in elevation of the multidirectional wheel equipped with a rotational locking device Figure 1 in the locked position and shown in section.

FIG. 4 shows in elevation a partial section of a conventional multi-directional wheel equipped with a locking device in rotation identical to that of FIG. 1 as well as a braking device according to a variant of the invention.

The figure shows a section along B B 'device. blocking of FIGS. 1, 2 and 4 supplemented by a view from above of the braking device according to FIG. 4.

Figure 6 shows in elevation a partial section of the multidirectional wheel equipped with a rotational locking device and a braking device of Figure 4 in the locked and braked position.

A tidirectional wheel consists of a wheel 1 (Figure 1) rotating about a horizontal wheel axis 2; the wheel 1 has a plane of wheel symmetry perpendicular to the horizontal axis of wheel 2 and is therefore vertical; the ends of the horizontal wheel axis are integral with a stirrup 3 in the shape of "U" reversed by the zones 4 corresponding to the end of the branches of "; the part of the stirrup 3 corresponding to the horizontal part of the "U" is a platform 5 secured, at a pivot zone 12, to a first element of a ball stopper 6, consisting of two pivoting elements; one with respect to the other; the axis of rotation of the ball stopper 6 is ver cal and located in the plane of wheel symmetry; i constitutes the vertical pivot axis 7 of the wheel 1 which is secant with the horizontal wheel axis 2 and which is integral with the second element of the ball stopper 6; the vertical pivot axis 7 of the wheel 1 is fixed on the frame 8 of the carriage so as to have a position perpendicular to the base of the wheels 1 of the carriage on the ground; and when the carriage is moved in a determined direction, each wheel 1 is rotated about the vertical pivot axis 7 of the wheel 1 so that the plane of wheel symmetry is parallel to the direction of travel of the carriage and that the projection 9 of the vertical voting axis 7 of the wheel 1 on the support base of the carriage is in front of the point of contact 11 of the wheel 1, 's in the direction of displacement; in these conditions wheel 1 is towed; as the load is transmitted to the wheel 1 via the vertical pivot axis and 1 horizontal wheel axis 2, the stirrup 3 is permanently subjected to a load transfer torque.

The invention is to provide a device for securing the handling of the. trolley as soon as it reaches a certain load, especially to secure the handling of the truck when the soi is in cant.

The invention consists in interposing, between the multidirectional wheel and the frame 8, a rotational locking device according to the vertical pivot axis 7 of the mutidirectional wheels of one of the front or rear wheel trains in at least one predetermined direction, that the loading of the carriage reaches a predetermined weight, by means of weighing means associated with means of FIG. 2 represents a cross-section of the device of FIG. 1 seen from above, along A A '.

Figure 3 shows a multidirectional wheel elevation equipped with a rotational locking device of Figure 1 in the locked position and shown in section.

The figure shows in elevation a partial section of a conventional multidirectional wheel equipped with a locking device in rotation identical to that of Figure 1 and a braking device according to a variant of the invention.

FIG. 5 represents a section along B B 'of the locking device of FIGS. 1, 2 and 4 completed by a view from above of the braking device according to FIG. 4.

Figure 6 shows in elevation a partial section of the multidirectional wheel equipped with a rotational locking device and a braking device of Figure 4 in the locked and braked position.

A tidirectional wheel consists of a wheel 1 (Figure 1) rotating about a horizontal wheel axis 2; the wheel 1 has a plane of wheel symmetry perpendicular to the horizontal axis of the wheel 2 and which is therefore vertical; the ends of the horizontal wheel axis are integral with a stirrup 3 shaped "U" reversed by the zones 4 corresponding to the end of the branches of the "U"; the part of the stirrup 3 corresponding to the horizontal part <B> lu ,, </ B> is a platform 5 integral, at a pivot zone 12, with a first element of a ball stopper 6, consisting of two elements pivoting relative to each other; the axis of rotation of the ball stopper 6 is tilted in a plane parallel to the plane of longitudinal symmetry about the horizontal wheel axis 2, so that the platform 5 of the stirrup 3 which was init they were horizontal inclined; the inclination is done so that the pivot area 12 of the platform 5 located around the point of application of the pivot axis ver 'cal 7 on the platform 5 is lowered by lowering frame 8 which is secured a blocking device 5 which comprises a notch 14 of appropriate shape which vi abrade on a locking zone 13 of the platform 5, opposite the pivot zone 12, situated in the vicinity of 1 'ntersection, with the platform 5, a plane passing through horizontal axis of wheel 2 and perpendicular to platform 5 of the stirrup 3, constituting a fixed locking means relative to the carriage.

In practical terms, the blocking device 15 (FIG. 1 and wheel 1 is fixed with respect to the frame 8 of the tank 'is composed in particular of a guiding device 6' of the vertical pivot axis 7 according to a first guide plane 21 parallel to the longitudinal plane of symmetry of the carriage, and according to a second vertical guide plane 22 and perpendicular to the first guide plane 21, the vertical guide device is composed of annular wedge 17 of the upper part of the vertical pivot axis 7 which is integral, at its base, adjacent the ball stopper 6 of a sliding device 18 (FIG. 1 and 2) cooperating with pairs of guide gliders 19 and 20, parallel between the two a two, and respectively parallel to the guide planes 21 and 22, the annular guide 17 maintains the vertical pivot axis 7 so that it can at least have possibility of pivoting parallel to the first guide plane 21; preferably two first guide rails 19, located on either side of the vertical pivot axis 7, according to the first guide plane 21 on the one hand and two second guide yokes 20, located on either side the vertical pivot axis 7 along the second guide plane 22 of share; the sliding device 18 rests and slides on these first and second guide rails 19 and 20, at least the slides 19 of which are flat surfaces, balancing said load transfer torque. whatever the orientation of the wheel 1. A first spring 23 or an equivalent device, constituting a weighing means, is placed between the sliding device 18 and the annular guide 17 and ensures the transfer of the charges' mposées by the chassis 8 , on the ball stopper 6, when it is empty; when loading the frame 8 with goods the first spring 23 compresses gradually; under these conditions the annular guide 17 approaches the ball stop 6 and the first and second guide rails 19 and 20 descend while the sliding device 18 remains in place. When the frame 8 reaches the predetermined load the position of the sliding device 18 is such that it is opposite an opening 24 constituting an interruption of at least one of the two second guide rails 20; under these conditions as the wheel 1 is oriented on the side of the first guide rails 19 and possibly to one of the second guide rails 20 which is not interrupted, the load transfer torque is balanced and the axis of vertical pivoting 7 remains in a vertical position; as soon as the wheel 1 (FIG. 3) is oriented towards one of the second guide rails 20 interrupted, the sliding device 18 is maintained only by the first gliders 19 and the load transfer torque is no longer balanced by the support of the sliding device 18 on the second interrupted guide rail 20, and the vertical pivot axis 7 tilts around the horizontal wheel axis 2, and the locking device 15 is lowered and the frame the cart; the locking zone 13 of the platform 5 of the stirrup 3 tilts to come to lock in the notch 14 fixed relative to the frame 8 and lock the wheel 1 parallel to the first guide plane 21.

One way of making the vertical guiding device consists, for example, in the use of a shell 16 of stamped sheet metal, the main opening 25, which is directed downwards, to cap ball stopper 6 ; it comprises four lateral walls which are flat and parallel in pairs to the part of their respective surface which is used as first or second guide rails 19 or 20; the two second guide rails 20 are spaced from the ball stopper 6 by a distance sufficient to tilt the latter in the shell 16 at the same time as that of the vertical pivot axis 7; bottom of the shell 16 is pierced with a hole serving as an annular guide 17 to the vertical pivot axis 7; this hole is, for example, a diameter greater than that of the vertical pivot axis 7 to allow a lateral movement of the latter 1 of the tilting; it is possible, for example, to perform a sleeving of this annular guide 17 vertically by a rubber ring which deforms during the lateral displacement of the vertical pivot axis 7. The sliding device 18 is constituted, for example, by a ane plate 26 substantially cruciform, the ends of the legs 28 and 27 slide on the first and second guide iss 19 and 20; it comprises in a central zone a hole, through which the tical pivoting axis 7 passes, and which is preferably associated with tubular 29 sliding around the tical pivot axis 7 to maintain the sliding device 18 perpendicularly to the tical pivot axis 7; at least one of the second slides 20 has an opening 24, constituting a gap of issière, of appropriate shape to that of the sliding device 18, placed above the contact points of the sliding device 18 on the first and second slides 19 and 20 when the carriage is empty and which at the height of the sliding device 18 .when the carriage reaches a predetermined load so that the sliding spositive 18 can enter through a branch end 27 and cause the tilting of the vertical pivot axis 7. The first coil spring 23 working in compression is placed around the vertical pivot axis 7 and the tubular guide 29; it is supported on the sliding device 18 by means of a first centering washer 30 threaded onto the tubular guide 29 and the bottom of the shell 16 by a second centering washer 30; it is sufficiently understood to balance the pressure exerted by the weight of the empty frame 8 with a predetermined dimension so that the opening 24 is above the sliding device 18. In an improvement of the invention, a second coil spring 31 also working in compression is placed around the vertical pivot axis 7 above the guide ring 17 and is compressed between two centering washers 32 threaded on the vertical pivot axis 7, by a nut 33 screwed to the end of the vertical pivot axis 7. The second spring 31 is intended to damp the oscillations created by. the load suppor by the frame 8; in one version of the invention the spring 31 is covered by a stamped sheet metal cap threaded onto the vertical pivot axis 7 by a central hole and secured to the pivot axis by pinching it between a shoulder of the axis 7 and the nut 33, the tubular guide 29 may be of a predetermined length to serve as a limiter of the depression of the shell 16 under an excessive load of the frame 8.

The edge of the shell 16 has below each opening 24 the notch 14 in which is housed the locking zone 13 of the platform 5 of the caliper 3 when from a predetermined load the sliding device 18 s' engages in the opening 24 constituting the interruption of slide.

When emptying the carriage there comes a time when the load becomes insufficient and the first spring 23 relaxes progressively lifting the frame 8 and causing the upright of the vertical pivot axis 7 and bringing the sliding device back to its resting position. the first and second slides and 20 and releasing the pivoting of the wheel 1 about the vertical pivot axis 7.

Such a blocking device 15 requires a higher load than is necessary for it to be able to hold in place because the operation of the springs is unbalanced when the vertical pivot axis has tilted; under conditions when the truck is insufficiently loaded so that the wheels can lock automatically, it can initiate blocking by pressing the hand or foot the frame in the vicinity of the wheels may be oqué, pulling the carriage forward to that the wheels are correctly inserted; the wheels lock and stay on top even though the load on the truck is slightly less than the minimum load required for locking the wheels.

In the variant of the invention, one way of producing the automatic braking device 36 is to extend the skirt 39 of the shell 40 all around its circumference and to conform it so that it can come to bear directly on the strip of bearing 41 of wheel 37 as soon as a predetermined load is reached; it is obvious that the part of the skirt which bears on the tread 41 of the wheel 37 may comprise a braking pad (not shown in the drawing); the extension of the skirt is, for example, constituted by a semicircular flat surface 42 (Figure 5) centered on the pivot axis 34 which is substantially perpendicular to it when the wheel 37 is not loaded; the semicircular flat surface 42 is described as semicircular because it is interrupted at the right of the notch 43 Bure 4) to come around it by a spoiler surface 44 (Figure 6) shaped to come to ensure the braking wheel 37 when locked in direction; the semicircular edge 45 (FIG. 4) of the semicircular flat surface 42 consists of a cylinder sector of revolution facing downwards; at the notch 43 (Bure 6) the spoiler surface 44 extends downwards so that its end, when the yoke 46 of the wheel 37 is in the notch 43, comes to bear on the strip 41 of the wheel 37. On the upper part of the shell 40 is a levi 47 may support directly or indirectly on the end of the pivot axis 34 of the wheel; the lever is for example articulated around a horizontal axis 48 fixed relative to the shell 40 to which it, for example, attached by a fixed support 49 and a first end 50 ent press the cabochon 51, whose shape is optionally adapted , while the second end 52 is rel "by a linkage (not shown in the drawings) to a control lever placed in the vicinity of the actuator bar of the carriage.

When filling the carriage, the frame 53 (Figure 4) drives the shell 40 which bears on the first spring 54 and lowers with respect to the wheel 37; if the latter is not in the vicinity of the notch 43, there comes a time when the end 55 of the semi-circular edge 45 of the shell 40 is pressed on the tread 41 of the wheel 37 and the born; the braking force becomes even more important the load of the truck is important; when the end 55 of the semi-circular edge 45 is in contact with the tread 41 of the wheel 37, the branch end 56 of the delivery device 57 is at the right of the opening 58 formed in the second slip, but does not engage in it; when it is desired to move the chari, the second end 52 (FIG. 4) of the lever is raised so that the first end 50 bears on the cap 51 and slides the shell 40 1 off the vertical pivot axis 34, disengaging the wheel 37 which can then roll again; the branch end 56 is no longer at the opening 58 and is again guided by the second slide 59; the wheel 37 can then again rotate freely without engaging in the notch 43, although the load in the carriage is greater than the load necessary to lock the wheel 37 in the direction since the overload is compensated by the action of the levi 47. On the other hand, if, when the sink 47 is released (FIG. 37), the wheel 37 is placed in line with the notch 43, the shell 40 descends along the vertical pivot axis 34 until that the branch end 56 of the sliding device 57 can engage in the opening 58 to cause the tilting of the vertical pivot axis 34 as previously described, while the stirrup 46 engages in the notch 43 until the tread 41 of the wheel 37 comes into contact with the end 60 of the swivel surface 44 which exerts braking, in which case the stirrup 46 is not supported as previously described on the bottom of the notch 43 to allow 'the eff. According to the invention, the braking force of the tilting axis 34 is limited, for example, by limiting the penetration of the end of the branch into the opening 57 by laterally positioned shoulders. pressing the edges 61 (Figure 5) of the opening 58 or by any suitable form to obtain the same result; when tilting, the branch end 56 moves away from the base 62 (FIG. 6) of the opening 58 which must be sufficiently high to allow positioning; under these conditions, when raising the second end 52 of the lever 47, the first end of the lever 47 presses on the cap 51 sliding the vertical pivot axis 34 in the guide ring 63 and the branch end 56 of the sliding device 57, which is supported by its shoulders on the edges 61 of the opening 58, moves along the opening 58; under these conditions the vertical pivot axis 34 begins to straighten and releases the wheel 37 which can roll while remaining locked in the direction. It is preferable, for safety reasons, to ensure that the lever can allow only a displacement of small amplitude n that the wheel 37 remains locked in direction when the load has reached its predetermined level; but nothing prevents increasing the amplitude of action of the lever 47 to return to the initial situation is a pivoting entirely 1i about vertical pivot axis 34; this implies that it can be done to the lever 47 only a partial stroke when it is desired that the wheel 37 remains locked direction when moving. In an improvement the invention it would be desirable for the guide ring to consist of a movable ball joint in a semi-toroidal housing placed laterally and traversed by vertical pivoting 34.

The braking device 36 may be used independently of the locking device 40 while remaining within the scope of the invention; under these conditions the shell 40 no longer has an opening 58 or notch for tilting the vertical pivot axis 34; the extension of the skirt 39 is then formed a circular circular surface centered on the vertical pivot axis 34 which is substantially perpendicular thereto; Circular flat surface rim consists of a cylinder of revolution turned down. As soon as the carriage has a predetermined load, the first spring 54 collapses sufficiently so that the extension of the skirt 39 skirt abuts on the tread 41 of the wheel 37 and this with a force proportional to the load of the cart.

Claims (1)

Claims 1 'securing device, a multidirectional wheel capable of being fixed to the chassis (8) (53) of a carriage, having a longitudinal plane of symmetry, which may comprise two sets of front and two multidirectional wheels of rear multidirectional wheels, consisting of a wheel (1) (37), having a tread (41, rotating about a horizontal axis of wheel (2) whose ends are integral with a stirrup (comprising a platform ( 5) comprising a pivoting zone (12) and locking zone (13), the pivot zone (12) being integral with a first element of a ball stop (6) having a second element integral with a vertical pivot axis (7), which is non-intersecting with the horizontal wheel axis (2) creating a load transfer torque, which is fixed on the chassis (8) so as to have a position perpendicular to the base of support wheels (1) of the truck on the ground, character if a locking device (15) (64), in the vertical pivot axis (7) (34), in at least one predetermined direction, is interposed between the directional wheel mul 'and the frame (8) (53) so that, as soon as the loading of the carriage reaches a predetermined weight, and the orientation of the wheels (1) (37) is parallel to the predetermined direction, the vertical pivot axis (7) switches, under the action of said load transfer torque, by means of guiding means (i7) (18) (19) (20) associated with weighing means (23) (31) and tilting means (24) , allowing tilting of the stirrup (3) so that the pivot zone (12) is lowered while the locking zone (13) blocks in the direction by means of locking means (14). 2-Device, according to claim 1, characterized in that the locking device (15) is fixed relative to the frame and is composed of a vertical darting device, the vertical pivot axis (7), following a first guide plane (21) parallel to said longitudinal plane of symmetry of the carriage and following a second vertical guide plane (22) perpendicular to the first guide plane 1), composed of an annular guide (7) of the upper part of the vertical pivot axis (7) which is integral, at its base, in the vicinity of the limit stop (6) of a sliding device (18) cooperating with pairs of guide rails (19) and (20), parallel to each other in pairs, and respectively to the guide planes (21) and (22). 3-Device according to claim 2, characterized in that the annular guide (17) holds the vertical pivot axis (7) so that it can at least have a possibility of pivoting parallel to the first guide plane (21), the first two guide rails (19) being located on either side of the vertical pivot axis (7), on the one hand and two second guide rails ( being located on either side of the "vertical" pivot axis (7) on the other hand, the sliding device (18) abutting and sliding on these first and second guiding slides (19) and 20) by balancing said load transfer torque regardless of the orientation of the wheel 1 until the predetermined weight is reached. 4-Device according to claims 1 to 3, characterized in that a weighing means is constituted by a first spring (23) to coil, working in compression, placed around the vertical pivot axis (7) between the sliding spoiler (18) and the annular guide (17) ensuring the transfer of the loads imposed by the frame on the ball stop (6), so that when the frame (8) is loaded, the first spring (23) gradually compresses, the annular guide (17) moves closer to the ball stop (6) and the first and second guide rails (19) and (20) descend while the sliding device (18) remains in place until the chassis (8) having reached the predetermined load, the position of the sliding device (18) is opposite an opening (24) constituting a tilting means which is an interruption of at least one two second guide rails (20), so that when the wheel (1) is oriented towards one of the second guide rails (20) interrupted, the vertically votable axis (7) tilts, around the horizontal axis wheel (2), and the locking zone (13). ) tilts to come to lock in a notch (14), constituting a fixed locking means relative to the frame (8), blocking the wheel (1) parallel to the first guide plane (21). 5-Device according to claims 2 to 4, characterized in that a means for producing said vertical guide device consists, in the use of a shell (16) (40), comprising a skirt (39), whose downwardly directed main opening (25) caps the ball stop (6) consisting of four sidewalls having the first guide rails (19) and the second guide rails (20) ( 59) and at least one aperture (24) (58), and a bottom pierced with a hole serving as an annular guide (17) (63), the slide device (18) (consisting of a flat plate (26), substantially cruciform, having branches whose ends branches (28) and (27) (58) slide on the first second guide rails (19) and (20) (59), the flat plate (26) being associated with a tubular guide (, sliding about the vertical pivot axis (7) (34), so that the sliding device (18) (57) is introduced through a branch end (27) (56) into the opening (24) (58) and causes the tilting of one vertical pivot axis (7) (34). 6 Device according to claim 4, characterized in that a second coil spring (31), worked in compression, is placed around the vertical pivot axis (7) above the guide ring (17). ) is compressed by a nut (33) screwed to the end of the vertical pivot (7). 7 'spositif, according to claim 5, characterized that the tubular guide (29) is of a predetermined length to serve as a limiter of the depression of the shell 6) under an excessive load of the frame (8). 8-Device according to claims 4 and 5, characterized in that the edge of the shell (16) has below each opening (24) one of the notches (14) in which housed the locking zone (13). 9-Device according to claim 5, characterized in that an automatic braking device (36) is associated with the locking device (64) and constituted by an extension of the skirt (39) of the shell (40) all around its circumference and conformation so that it can come to rest right on the tread (41) wheel (37) as soon as the predetermined load is reached, the neutralization of the automatic braking device being obtained by a first (47) ), articulated about a horizontal axis (48) fixed to the frame (53), having a first end (50) and a second end (52), the first end (50) being able to directly support or ' ndirectly on the end of the pivot axis (34) wheel (37) to slide it through the ring. (63), the second end (52) being connected by linkage to a control lever placed in the vicinity of the truck operating bar. 10-Device according to claim 9, characterized in that an automatic braking device uses a locking device (40) which has been removed from the opening (58) and the notch (43) so as to obtain a braking from a predetermined load of the carriage without blocking towards the wheel (37).