Transport trolley with suspended wheels and with a real estate cushion

Description

[0001] The present invention relates to a transport trolley with suspended wheels equipped with a locking pad.

[0002] To avoid any ambiguity in understanding the invention, the terms "cart" and "transport cart" are equivalent.

[0003] A transport trolley according to the invention includes both a simple trolley that can be pushed by hand, and a rolling base that can be pushed by hand and towed.

[0004] Such a transport cart ,Such as those described in US documents 2006 / 082088 A1, CN 106 931 280 A, CN 102 923 375 A, US 2 712 366 A, or US 4 655 466 A, comprises a horizontal rolling structure mounted on a plurality of casters, each with associated suspension. Various objects are placed on the rolling structure, and the cart is then moved manually or by means of a motor to transport these objects to a specific destination within a facility. Such movement can be a few tens of meters, but can also extend to several kilometers. This cart may or may not include a guiding element in the form of a control bar, capable of orienting the cart during its movement to reach the desired destination.During certain phases of use of this trolley, for example when loading or unloading it, it is imperative that the trolley be stabilized on the ground, otherwise loading or unloading will become very difficult. Indeed, during such operations, if the trolley were free to move, it would be difficult to keep it stationary, and it would then move abruptly and unpredictably in any direction with each loading or unloading of objects. There are two other situations related to the possible movement of the trolley: when a forklift operator attempts to place or pick up a load on the rolling stock, when the ground is sloping. To address this problem of unexpected and therefore uncontrolled movement, trolleys are generally equipped with a locking pad, the activation of which The manual mechanism allows the pad, which was initially positioned above the ground, to be moved vertically downwards, so that it rests closely against the ground and acts as a locking stop. Once this pad is in contact with the ground, it very slightly lifts the trolley, preventing the trolley from moving on the ground.

[0005] Current locking skids are designed to work only with trolleys equipped with non-suspension casters. However, the main difference between a trolley with suspension casters and one without is that the rolling structure of a trolley with suspension casters can lower significantly under the weight of the objects placed on it. This significant lowering can be several centimeters, for example. For these trolleys with suspension casters, manually activating a locking skid can be difficult or even impossible when the weight of the objects placed on the rolling structure is very high. Indeed, in these circumstances, a very high, even immense, effort would be required to lift the rolling structure.

[0006] A transport trolley according to the invention has suspension casters and has a locking pad designed to be easily operated, regardless of the mass of the objects placed on the rolling structure of said transport trolley.

[0007] The invention relates to a transport trolley comprising a rolling structure, suspended casters on which said rolling structure is mounted, a locking pad and an activation mechanism for this locking pad to prevent the trolley from moving on a floor by means of said suspended casters, characterized in that the activation mechanism of the locking pad comprises: a hollow main body attached to a lower surface of the rolling base and extending vertically, a hollow slide terminating in a widened end, said slide being inserted into the main body so that its widened end constitutes its lowest part, a rod around which extends a first spring, said rod and said first spring being inserted into the slide, a cylindrical compensator to which the locking pad is attached, said compensator being inserted between the first spring and an internal surface of the slide, abutting against said first spring, so that the locking pad emerges from the widened end of the slide, a locking pedal mounted to rotate about a first axis of rotation of the hollow main body,said locking pedal being capable of passing by rotation from a deactivation position, in which it extends horizontally, to an activation position, in which it extends vertically, an elongated connecting rod, the upper end of which is mounted for rotation about a second axis of rotation of the locking pedal, and the lower end of which is mounted for rotation about a third axis of rotation of the enlarged end of the slide, and during the passage of the locking pedal from the deactivation position to the activation position, the connecting rod pivots about the second axis of rotation of said locking pedal to become aligned along the locking pedal in a substantially vertical direction, the slide simultaneously passing from an raised position to a lowered position.

[0008] All the components in the deployment mechanism of the immobilizing pad of a transport trolley according to the invention are sized and arranged to allow the immobilizing pad to be deployed with minimal effort, regardless of the weight of the objects placed on the rolling structure. Schematically, rotating the locking pedal to the activation position causes the connecting rod to rotate, which initially lowers the slide, accompanied by a stretching of the first spring until the immobilizing pad, initially above the ground, makes contact with it. This lowering requires some effort, as the stretching of the first spring counteracts its natural tendency to compress.The locking pedal continues to rotate once the locking pad reaches the ground, until the connecting rod and the locking pedal are aligned in a nearly vertical direction. During this second phase, the first spring naturally compresses within the slide to return to its relaxed position, creating pressure between the ground and the underside of the rolling cart. It is primarily this natural compression of the first spring that allows the rolling base to be easily raised using the locking pedal. Depending on the weight of the objects placed on the rolling base, the compensator, to the end of which the locking pad is attached, will retract more or less deeply into the slide.It is primarily thanks to the natural compression of the first spring that the rolling structure can be easily raised using the locking pedal, without an operator having to exert significant effort to counteract the weight of objects placed on it. Preferably, the slide and the tube are cylindrical. Advantageously, the locking pedal is a straight rod. To avoid any ambiguity, when the locking pedal is in the deactivated position, the locking pad is above the ground and has no specific function, and when the locking pedal is in the activated position, the locking pad is in close contact with the ground to prevent any movement of the trolley on the ground.

[0009] According to one possible feature of the invention, the connecting rod comprises two widely spaced and parallel arms, and the main body comprises two widely spaced and parallel flat walls, with the two arms of the connecting rod enclosing the two parallel walls of the hollow main body. A connecting rod with two parallel arms is more robust than one with only one arm. Furthermore, thanks to the presence of its two arms framing the main body, the connecting rod acts in a homogeneous and balanced manner within the deployment mechanism of the immobilizing skid.

[0010] According to one possible feature of the invention, the locking pedal comprises two separate, parallel sections, the locking pedal being mounted on the main body by clamping the two arms of the connecting rod. A locking pedal with two parallel sections is more robust than a locking pedal with only one section. Furthermore, thanks to the presence of its two sections framing the two arms of the connecting rod, the locking pedal acts in a homogeneous and balanced manner within the deployment mechanism of the immobilizing pad.

[0011] According to one possible feature of the invention, the locking pedal terminates in a segment folded at a right angle, said folded segment serving as a support surface for the foot of an operator wishing to rotate the locking pedal around the first axis of rotation towards the activation position. This segment folded at a right angle facilitates placing the operator's foot against the locking pedal in order to rotate said locking pedal.

[0012] According to one possible feature of the invention, the first axis of rotation, the second axis of rotation and the third axis of rotation extend horizontally.

[0013] According to one possible feature of the invention, the locking pad is cylindrical and is attached to one end of the cylindrical compensator by means of a screw. Advantageously, the locking pad ideally extends beyond the compensator without protruding laterally from it. Preferably, the thickness of the locking pad is greater than or equal to 0.5 mm so as to constitute a robust part that is unlikely to wear quickly.

[0014] According to one possible feature of the invention, the activation mechanism comprises a release pedal pivotally mounted about a fourth axis of rotation of the main body and having a push pin. This mechanism includes a second pre-tensioned spring, one end of which is fixed to the main body and the other end of which is fixed to the enlarged end of the slide. Rotating the release pedal about the fourth axis of rotation deactivates the locking pad, causing the push pin to bear against the connecting rod, which then becomes misaligned with the locking pedal. The connecting rod's movement is furthered by compression of the second spring, which tends to return to its rest position and causes the slide to rise. The locking pad could have been deactivated by means of the locking pedal.Indeed, it would have been sufficient to rotate the locking pedal in the opposite direction from its activation position to reach the deactivation position. However, in its activation position, the locking pedal remains very difficult to operate, as it would require an operator to slide their foot under the pedal, which is very close to the ground, and then exert force to rotate it in the opposite direction. The unlocking pedal is easily operated by simply pressing the foot to deactivate the locking pad. The push pin and the second spring are inserted into the mechanism to facilitate the reverse movement of all the components that were displaced when the locking pedal was placed in the activation position.The term "reverse direction" should be interpreted in relation to the direction of manipulation of the locking pedal to move from the deactivation position to the activation position.

[0015] According to one possible feature of the invention, the unlocking pedal is connected to the main body by means of a third pre-stressed spring requiring the application of a certain force on the unlocking pedal to overcome said third spring, when the unlocking pedal is rotated around the fourth axis of rotation to deactivate the immobilizing pad.

[0016] The invention also relates to a method for activating the immobilizing pad of a transport trolley according to the invention, the locking pedal being assumed to be in a deactivation position.

[0017] According to the invention, the activation process comprises the following steps: a step of rotating the locking pedal around the first axis of rotation from the deactivation position in which said pedal and the connecting rod are separated from each other to form an open compass, this rotation being effected by means of a push exerted by the foot of an operator on said locking pedal and causing the connecting rod to pivot around its two ends towards a vertical position, a step of lowering the slide under the effect of the pivoting of the connecting rod until the locking pad touches the ground, the first spring being pre-loaded until said locking pad touches the ground, a step of continuing the rotation of the locking pedal while the locking pad has already touched the ground, until the connecting rod reaches the end of its stroke in a vertical position aligned with the locking pedal to form a closed compass,The first spring, having initiated a compression phase just after the immobilizing pad touched the ground, the slider continuing its descent, a stage of pressure creation between the ground and the underside of the transport trolley corresponding to a maximum compression of the first spring, which is not a 100% compression, since it is the wheel suspensions that are compressed to the maximum and which provide a mechanical stop for the rolling structure, this stage being accompanied by a more or less significant penetration of the compensator equipped with the immobilizing pad inside the slider.

[0018] The invention also relates to a method for deactivating the immobilizing pad of a transport trolley according to the invention, the locking pedal being assumed to be in an activation position.

[0019] According to the invention, the deactivation process comprises the following steps: a step of rotating the unlocking pedal around the fourth axis of rotation, this rotation being carried out by means of a push exerted by the foot of an operator on said unlocking pedal, the connecting rod being aligned along the locking pedal, a step of pressing the push pin against the connecting rod causing a displacement of said connecting rod which begins to misalign with the locking pedal, a step of compressing the second pre-stressed spring which tends to naturally return to its rest position, this compression step being accompanied by a rise of the slider to which one end of said second spring is attached, a step of pivoting the locking pedal towards its deactivation position, initiated by the push pin and relayed by the compression of the second spring, a step of raising the immobilizing pad which is no longer in contact with the ground.

[0020] A detailed description of a preferred embodiment of a trolley according to the invention is given below, with reference to the following figures: [ Fig. 1 ] is a side view of a stabilizing skid mechanism for a transport trolley according to the invention, [ Fig. 2 ] is an exploded perspective view of the mechanism of the figure 1 , [ Fig. 3 ] is a perspective view of the mechanism of figures 1 And 2 , with the locking pedal deactivated, Fig. 4 ] is a perspective view of the mechanism of the figure 3 , with the locking pedal activated, , Fig. 5 ] is a side and transparent view of a lower area of ​​the mechanism of the figure 4 , [ Fig. 6 ] is a perspective view of a transport trolley activation pad mechanism according to the invention, showing a release pedal, [ Fig. 7 ] is a perspective view from another angle of the mechanism of the figure 6 , [ Fig. 8 ] is a side view of a stabilizing skid mechanism for a transport trolley according to the invention, with the locking pedal not activated, [ Fig. 9 ] is a cross-sectional view of the mechanism of the figure 8 , [ Fig. 10 ] is a side view of a stabilizing skid mechanism for a transport trolley according to the invention, with the locking pedal activated and said trolley empty, [ Fig. 11 ] is a cross-sectional view of the mechanism of the figure 10 , [ Fig. 12 ] is a side view of a stabilizing skid mechanism for a transport trolley according to the invention, with the locking pedal activated and said trolley loaded, [ Fig. 13 ] is a cross-sectional view of the mechanism of the figure 8 , [ Fig. 14 [ ] is a perspective view of a transport trolley according to the invention ,

[0021] By referring to figures 1 , 2 And 14A transport trolley 50 according to the invention comprises a rolling structure 1 mounted on a plurality of casters 51, each associated with a suspension 52. The rolling structure 1 is flat and horizontal and is intended to be loaded with objects, which will be conveyed to a specific destination within a facility by means of the movement of the transport trolley 50. This rolling structure 1 may, for example, be tubular in order to lighten the transport trolley 50. This transport trolley 50 may or may not be equipped with a guiding element, such as a control bar 53, also called a handrail, to orient the trolley 50 during its movement. The trolley 50 is made to roll on the ground by means of its suspended casters 51, 52.A distinctive feature of this type of trolley 50 is that the rolling structure 1, due to the presence of the suspended casters 51 and 52, can be lowered significantly, by several centimeters, if the objects being transported and placed on the rolling structure 1 are heavy, typically exceeding several hundred kilograms. It is therefore important to be able to immobilize this transport trolley 50 during, for example, loading or unloading operations. Indeed, during these phases, if the trolley 50 were not immobilized, it could move suddenly in any direction if accidentally pushed. This is also true if the trolley 50 had to be stopped while on a slope. Without the deployment of a locking skid, it would not be able to remain in place.Deploying a locking skid on such a trolley 50 is complicated by the presence of suspended casters 51, 52, which significantly lower the rolling structure 1, typically by a few centimeters, when it is loaded with heavy objects. Indeed, raising the trolley 50 to make the locking skid effective can be difficult or even impossible due to the trolley's considerable mass caused by the presence of these heavy objects.

[0022] By referring to figures 1 , 2 , 3 And 4 , to solve this problem of implementing a locking pad 10 on a trolley 50 having suspended casters 51, 52, a trolley 50 according to the invention comprises a rolling structure 1 mounted on suspended casters 51, 52, and a deployment mechanism for said locking pad 10 comprising: a main body 3 hollow of substantially parallelepiped shape, a connecting rod 4, a locking pedal 5, an unlocking pedal 6, a slide 7, a first spring 22, a compensator 9, a locking pad 10.

[0023] The connecting rod 4 comprises two parallel, widely spaced arms 11 and 12, said two arms being connected to each other by means of a flange 13. Preferably, the connecting rod 4, comprising the two widely spaced arms 11 and 12 and the flange 13, is made in a single piece of the same material. The two arms 11 and 12 are flat and thin, and the flange 13 has three thin walls, two of whose lateral walls are parallel and each extends from an arm 11 or 12, and a connecting wall connects said two lateral walls by extending perpendicularly to them. The locking pedal 5 comprises two separate, parallel sections 14 and 15, each terminating in a segment 16 folded at approximately 90°, said two folded segments 16 being connected to each other by means of a connecting segment 17.The two folded segments 16 and the connecting segment 17 define an end frame against which an operator's foot will exert pressure to move the locking pedal 5 in order to deploy the immobilizing pad 10. The locking pedal 5 is mounted for rotation about a first axis of rotation 18 of the main body 3. More specifically, the main body 3 is delimited by two parallel side walls, and the first axis of rotation 18 emerges from an upper area of ​​the external surfaces of said two side walls. The connecting rod 4 is mounted for rotation about a second axis of rotation 19 carried by the locking pedal 5, said second axis 19 emerging from the external surfaces of the two sections 14, 15 of said locking pedal 5. The first axis of rotation 18 and the second axis of rotation 19 are parallel and extend horizontally.The locking pedal 5, the connecting rod 4 and the hollow main body 3 are arranged in such a way that: . the two arms 11, 12 of the connecting rod 4 enclose the two parallel lateral walls of the main body 3, and the two sections 14, 15 of the locking pedal 5 enclose the two arms 11, 12 of the connecting rod 4.

[0024] To summarize, the locking pedal 5 is rotationally mounted on the main body 3 around the first axis of rotation 18, and the connecting rod 4 is rotationally mounted on the locking pedal 5 around the second axis of rotation 19 so that it is located between the main body 3 and the locking pedal 5.

[0025] By referring to figures 1 , 2 , 3 , 4, 5, 6 And 7The slide 7 is a hollow cylindrical piece, one end of which, viewed along its axis of revolution, terminates in a widened flange 20. A rod 21, around which the first spring 22 extends, is inserted into the slide 7. The first spring 22 is free to be compressed or stretched along the rod 21. A cylindrical stop 23 is fixed to the first spring 22, being positioned around said first spring 22. When the rod 21 and the first spring 22 are inserted into the slide 7, said first spring 22 is in contact with an internal wall of the slide 7. The slide 7 is inserted into the main body 3 so that it extends in a substantially vertical direction and its end, terminating in the widened flange 20, constitutes its lowest point. The slide 7 is free to slide vertically within the main body 3.

[0026] The main body 3 originates on a lower surface of the rolling structure 1 and extends downwards beneath said rolling structure 1 in a vertical direction. Each arm 11, 12 of the connecting rod 4 has an upper end that is rotatably mounted about the second axis of rotation 19 of the locking pedal 5, and a lower end that is rotatably mounted about a third axis of rotation 24 passing through the enlarged flange 20 of the end of the slide 7. The upper and lower ends of each arm 11, 12 of the connecting rod 4 are to be considered along a longitudinal axis of the connecting rod, said upper end being positioned above the lower end. The compensator 9 is a hollow cylindrical part, and the locking pad 10 is a solid cylindrical part whose diameter is substantially equal to the diameter of the compensator 9.Advantageously, the locking pad 10 is screwed to one end of the compensator 9. The compensator 9 is inserted into the slide 7, so that the locking pad 10 emerges from the enlarged collar 20 of said slide 7, said compensator 9 being at least partly included in said slide 7 by surrounding the first spring 22.

[0027] By referring to figures 3 , 8 And 9The locking pedal 5 can be in a deactivation position in which the immobilizing pad 10 is not activated. In this deactivation position, the locking pedal 5 extends horizontally and the immobilizing pad 10 is positioned above the ground without being in contact with it. The connecting rod 4 and the locking pedal 5 form an open compass, the axis of rotation of which is defined by the second axis of rotation 19 around which the connecting rod 4 pivots. In this open compass, the connecting rod 4 and the locking pedal form an angle greater than 90°. An operator wishing to deploy the immobilizing pad 10 to prevent any movement of the transport trolley 50 on the ground will apply pressure with their foot to the end frame 16, 17 of the locking pedal 5. The following steps will then occur: A pivoting step of the locking pedal around the first axis of rotation 18 causes the connecting rod 4 to rotate around the second axis of rotation 19, with the angular gap between the locking pedal 5 and the connecting rod 4 gradually decreasing. In other words, the angular opening of the compass formed by the connecting rod 4 and the locking pedal 5 gradually decreases as the locking pedal approaches the activation position. A lowering step of the slider 7 results in vertical sliding within the main body 3, due to the rotation of the connecting rod 4, until the locking pad 10 initially makes contact with the ground.During this phase, the first spring 22 was stretched and thus placed under tension, a step of continuing the pivoting of the locking pedal 5, once the immobilizing pad 10 touched the ground, until said connecting rod 4 and said locking pedal 5 aligned with each other along a substantially vertical direction. For this configuration, the angular opening of the compass formed by the connecting rod 4 and the locking pedal 5 becomes zero. The locking pedal 5 then reached an activation position. Referring to the... figures 10 et 11 When the transport trolley 50 is lightly loaded, the locking pad 10 emerges quite clearly from the enlarged end 20 of the slide 7 when the locking pedal 5 is in the activation position. Referring to figures 12 et 13 When the transport trolley 50 is heavily loaded, the locking pad 10 barely emerges from the enlarged end 20 of the slide 7 when the locking pedal 5 is in the activated position. During this phase of continued pivoting of the locking pedal 5, the first spring 22, which was previously under tension, naturally compresses to try to return to its relaxed position, causing the compensator 9, equipped with the locking pad 10, to retract into the slide 7. The compression of the first spring 22 facilitates the deployment of the locking pad 10 by applying pressure to said pad 10 against the ground. The compression of the first spring 22 is not 100% compression, since it is the suspensions 52 of the casters 51 of the transport trolley 50 that are compressed to the maximum and provide a mechanical stop for the rolling base 1.

[0028] By referring to figures 1 , 2 , 4, 6 , And 7 The deployment mechanism for the immobilizing pad 10 includes a release pedal 6 to deactivate the immobilizing pad 10. Indeed, the immobilizing pad 10 could have been deactivated by rotating the locking pedal 5 in the opposite direction. However, once the locking pedal 5 reaches the activation position, it becomes very difficult to operate because the operator's foot would have to pass under the locking pedal 5 to exert pressure on it in order to trigger this reverse rotation. In the activation position, the locking pedal 5 is so low that inserting the foot between it and the ground would require considerable effort, potentially leading to foot injury.

[0029] By referring to figures 2 , 6 And 7The unlocking pedal 6 consists of an elongated rod 25, of which: a first end is mounted in rotation around a fourth axis of rotation 26 fixed to the main body 6 in a lower area thereof, said fourth axis of rotation 26 being placed under the first axis of rotation 18 around which the locking pedal 5 is mounted in rotation, and a second end terminates in a segment 27 folded at 90°, said folded segment being intended to serve as a support surface for the foot of an operator wishing to activate this unlocking pedal 6.

[0030] These two ends must be considered along a longitudinal axis of the rod 25. The first end of the rod 25, constituting the release pedal 6, carries a lever arm 28 that extends perpendicularly to a longitudinal axis of the rod 25 and perpendicularly to the folded segment 27 of the second end of said rod 25. This lever arm 28 carries a push pin 29 that is parallel to the fourth axis 26 of rotation, this push pin 29 being cylindrical and elongated. A second spring 30 connects an upper area of ​​the main body 3 to the enlarged collar 20 of the slide 7, said second spring 30 being pre-stressed when stretched and thus tending to naturally compress to return to a relaxed position. The release pedal 6 has a secondary rod 31 extending parallel to the lever arm 28 and having a length equal to that of said lever arm 28.The release pedal 6 is mounted in the deployment mechanism of the immobilizing pad 10 by means of a third spring 32 connecting an upper area of ​​the main body 3 to a free end of the secondary rod 31.

[0031] The release pedal 6 can only be used when the locking pedal 5 is in the activated position, in which case the immobilizing pad 10 is deployed to prevent any movement of the transport trolley 50 on the ground. A method for deactivating the immobilizing pad 10 using the release pedal 6 comprises the following steps: a step of rotating the unlocking pedal 6 around the fourth axis of rotation 26 by means of a push exerted by the foot of an operator on the folded segment 27 of said unlocking pedal 6, the connecting rod 4 being aligned along the locking pedal 5, a step of pressing the push pin 29 against the connecting rod 4 due to the rotation of the unlocking pedal 6, causing a displacement of said connecting rod 4 which begins to misalign with the locking pedal 5, a step of compressing the second pre-stressed spring 30 which tends to naturally return to its rest position, this compression step being accompanied by a rise of the slide 7 to which one end of said second spring 30 is attached, a step of pivoting the locking pedal 5 towards its deactivation position, initiated by the push pin 29 and relayed by the compression of the second spring 30,a step involving the raising of the immobilizing pad 10, which is no longer in contact with the ground.

Claims

1. Transport trolley (50) comprising a rolling structure (1), suspended castors (51, 52) on which said rolling structure (1) is mounted, an immobilizing pad (10) and a mechanism for activating said immobilizing pad to prevent the trolley (50) from moving on a ground on said suspended castors (51, 52), characterized in that the activation mechanism of the immobilizing pad (10) comprises: - a hollow main body (3) secured to a lower surface of the rolling structure and extending vertically, - a hollow slide (7) terminating in a widened end (20), said slide (7) being inserted into the main body (3) so that its widened end (20) constitutes its lowest part, - a rod (21) about which a first spring (22) extends, said rod (21) and said first spring (22) being inserted into the slide (7), - a cylindrical compensator (9) to which the immobilizing pad (10) is fastened, said compensator (9) being inserted between the first spring (22) and an inner surface of the slide (7) coming into abutment against said first spring (22), so that the immobilizing pad (10) emerges from the widened end (20) of the slide (7), - a locking pedal (5) mounted in rotation about a first rotation axis (18) of the hollow main body (3), said locking pedal (5) being rotatable from a deactivation position in which it extends horizontally to an activation position in which it extends vertically, - an elongate connecting member (4), an upper end of which is mounted in rotation about a second rotation axis (19) of the locking pedal (5), and a lower end of which is mounted in rotation about a third rotation axis (24) of the widened end (20) of the slide (7), and in that when the locking pedal (5) is moved from the deactivation position to the activation position, the connecting member (4) pivots about the second rotation axis (19) of said locking pedal (5) so as to be realigned along the locking pedal (5) in a substantially vertical direction, the slide (7) simultaneously moving from a raised position to a lowered position.

2. Transport trolley according to Claim 1, characterized in that the connecting member (4) comprises two spaced apart, parallel arms (11, 12), and in that the main body (3) comprises two spaced apart, parallel planar walls, and in that the two arms (11, 12) of the connecting member (4) enclose the two parallel walls of the hollow main body (3).

3. Transport trolley according to Claim 2, characterized in that the locking pedal (5) comprises two separate, parallel sections (14, 15), and in that the locking pedal (5) is mounted on the main body (3) enclosing the two arms (11, 12) of the connecting member (4).

4. Transport trolley according to any one of Claims 1 to 3, characterized in that the locking pedal (4) terminates in a segment (16) folded at right angles, and in that said folded segment (16) acts as a bearing surface for the foot of an operator wishing to pivot the locking pedal (5) about the first rotation axis (18) towards the activation position.

5. Transport trolley according to any one of Claims 1 to 4, characterized in that the first rotation axis (18), the second rotation axis (19) and the third rotation axis (24) extend horizontally.

6. Transport trolley according to any one of Claims 1 to 5, characterized in that the immobilizing pad (10) is cylindrical and is fastened to one end of the cylindrical compensator (9) by means of a screw.

7. Transport trolley according to any one of Claims 1 to 6, characterized in that the activation mechanism comprises an unlocking pedal (6) pivotingly mounted about a fourth rotation axis (26) of the main body (3) and having a push pin (29), and in that said mechanism includes a second preloaded spring (30) of which one end is fastened to the main body (3) and another end is fastened to the widened end (20) of the slide (7), a rotation of the unlocking pedal (6) about the fourth rotation axis (26) to deactivate the immobilizing pad (10) causing the push pin (29) to bear against the connecting member (4), which is then offset from the locking pedal (5), the movement of the connecting member (4) being facilitated by a compression of the second spring (30), which tends to return to its rest position and causes the slide (7) to rise.

8. Transport trolley according to Claim 7, characterized in that the unlocking pedal (6) is connected to the main body (3) by means of a third preloaded spring (32) requiring the application of a given force on the unlocking pedal (6) to overcome said third spring (32), when the unlocking pedal (6) is rotated about the fourth rotation axis (26) to deactivate the immobilizing pad (10).

9. Method of activating the immobilizing pad (10) of a transport trolley (50) according to any one of Claims 1 to 8, the locking pedal (5) being assumed to be in a deactivation position, characterized in that it comprises the following steps: - a step of rotating the locking pedal (5) about the first rotation axis (18) from the deactivation position, in which said pedal (5) and the connecting member (4) are separated from each other to form an open angle, this rotation being effected by the foot of an operator pushing said locking pedal (5) and causing the connecting member (4) to pivot about its two ends towards a vertical position, - a step of lowering the slide (7) under the effect of the pivoting of the connecting member (4) until the immobilizing pad (10) touches the ground, the first spring (22) being preloaded until said immobilizing pad (10) touches the ground, - a step of continuing the rotation of the locking pedal (5) once the immobilizing pad (10) has touched the ground, until the connecting member (4) reaches the end of travel in a vertical position, aligned with the locking pedal (5) to form a closed angle, the first spring (22) initiating a compression phase just after the immobilizing pad (10) touches the ground, the slide (7) continuing to move downwards, - a step of creating a pressure between the ground and the underside of the transport trolley (50) corresponding to a maximum compression of the first spring (22) which is not a 100% compression, since it is the suspensions (52) of the castors (51) which are fully compressed and which provide a mechanical stop for the rolling structure (1), this step being accompanied by a greater or lesser penetration of the compensator (9) fitted with the immobilizing pad inside the slide (7).

10. Method of deactivating the immobilizing pad (10) of a transport trolley (50) according to either one of Claims 7 and 8, the locking pedal (5) being assumed to be in an activation position, characterized in that it comprises the following steps: - a step of rotating the unlocking pedal (6) about the fourth rotation axis (26), this rotation being effected by the foot of an operator pushing said unlocking pedal (6), the connecting member (4) being aligned along the locking pedal (5), - a step of the push pin (29) bearing against the connecting member (4) to move said connecting member (4) which begins to be offset from the locking pedal (5), - a step of compressing the preloaded second spring (30) which tends to naturally return to its rest position, this compression step being accompanied by a rise of the slide (7) to which one end of said second spring (30) is fastened, - a step of pivoting the locking pedal (5) towards its deactivation position, initiated by the push pin (29) and relayed by the compression of the second spring (30), - a step of raising the immobilizing pad (10) which is no longer in contact with the ground.