WO2023052435A1

WO2023052435A1 - System for blocking a vehicle in front of a loading dock

Info

Publication number: WO2023052435A1
Application number: PCT/EP2022/076998
Authority: WO
Inventors: Ignacio BELLOTA
Original assignee: Asa Fermetures
Priority date: 2021-09-28
Filing date: 2022-09-28
Publication date: 2023-04-06
Also published as: FR3127487B1; FR3127487A1

Abstract

The invention relates to a system (1) for blocking a vehicle (C) in front of a loading dock, the system comprising a guide rail (2), a carriage (3, 30) mounted so as to be movable on the rail, a first device (4) for driving the carriage on the rail, a wedge (5) mounted so as to be movable on the carriage, and a second device (6) for driving the wedge between a blocking position and a withdrawn position, characterised in that the guide rail comprises a plurality of locking members (22a) arranged along the rail and a movable immobilisation device (8, 80) carried by the carriage and capable of assuming a locked configuration, in which it engages with at least one of the locking members, and an unlocked configuration, the immobilisation device being arranged to be driven by the wedge in order to adopt said locked configuration.

Description

Title of the invention: SYSTEM FOR BLOCKING A VEHICLE IN FRONT OF A LOADING DOCK

The invention relates to the field of transit of goods between a truck and a building. More specifically, the invention relates to the field of the safety of loading or transhipment docks.

[0002] Upstream of a transshipment operation from a truck to a loading/unloading dock, it is essential to be able to immobilize the vehicles in front of the loading docks in order to avoid any accident linked to a possible untimely start. of the vehicle, for example when a pedestrian passes or when the driver is still loading. [0003] For these purposes, immobilization systems are known comprising a carriage mounted to slide on a rail extending along the parking area so as to be able to be moved manually by an operator at the level of a train of wheels of a vehicle to be immobilized. The carriage is provided with a wedge that can assume two positions, a blocking position and a retracted position. When the carriage is positioned at the wheel set, the operator deploys the wedge to its locking position so that it is positioned against the wheel set. A mechanism for locking the carriage on the rail then makes it possible to immobilize it in translation and therefore to immobilize the vehicle, via the wedge.

[0004] More sophisticated immobilization systems are also known, in which a first drive device makes it possible to automatically move the carriage at the level of the wheel set, without manual intervention by an operator, and a second drive device automatically moves the wedge to the locking position. The drive devices are hydraulic systems, which thus make it possible to lock the chock and the carriage in position in order to immobilize the vehicle and resist an untimely start of the vehicle without risk of degrading the system.

[0005] While this type of automatic system is indeed effective, it nevertheless has various drawbacks. On the one hand, the use of hydraulic cylinders requires the use of lubricating oil which should be drained regularly, which leads to problems of cost, pollution, reliability and noise. In addition, hydraulic systems are particularly bulky.

[0006] Furthermore, it is not conceivable to replace these hydraulic cylinders with another type of drive device, such as an electric motor, insofar as the power developed by an electric motor is substantially less than that of a hydraulic cylinder and cannot resist starting a vehicle, in particular when it is a heavy vehicle. Although an electric motor could overcome the various drawbacks of a hydraulic cylinder, it is therefore incompatible with such an automatic system.

The invention is thus placed in this context, and thus aims to solve the various problems identified by proposing a system for automatically blocking a vehicle in front of a loading dock, which can use drive devices of a cart and a chocks other than a hydraulic system while guaranteeing immobilization of the vehicle, including in the event of accidental starting of this vehicle.

[0008] For these purposes, the subject of the invention is a system for locking a vehicle in front of a loading dock, the system comprising a guide rail, a carriage mounted movable in translation on the guide rail, a first device for driving the carriage in translation on the rail, a wedge mounted movable in translation on the carriage in a direction transverse to the guide rail, a second device for driving the wedge in translation capable of causing movement of the wedge on the carriage between a blocking position and a retracted position, characterized in that the guide rail comprises a plurality of locking members arranged along the guide rail and a mobile immobilizing device carried by the carriage and capable of borrowing a locked configuration in which it cooperates with at least one of the locking members to immobilize the carriage on the rail and an unlocked configuration and in that the guide rail comprises a transmission member, the first drive device being arranged to cooperate with said transmission member to cause a translational movement of the carriage on the rail and in which the locking members are formed by the transmission member. .

In other words, in the present invention, when the immobilizer is in its unlocked configuration, it is free with regard to the locking members of the guide rail and the carriage can therefore move freely on the rail. , by means of the first drive device, to be positioned at a wheel of a vehicle to be immobilized. When the carriage is positioned, the second drive device then moves the wedge so that it assumes its locking position by coming substantially against this wheel. In this position, the immobilizer then locks itself by cooperating with one or more locking members of the rail to prevent movement of the carriage along the rail. The trolley is therefore immobilized, as is the vehicle. It is therefore not necessary for the first driving device and/or the second driving device to be able to develop a significant power, since neither of them plays a role in the immobilization of the trolley but only in the movement of the trolley and the wedge. It is therefore conceivable, in a system according to the invention, to employ lower power drive devices, such as electric motors.

In the invention, the guide rail can be supported by a frame forming a support plane on the ground, on which can circulate a vehicle to be immobilized, which thus moves along the rail. The guide rail may be a substantially horizontal rectilinear part, for example of circular or rectangular or H-shaped section, and extending at a distance from the frame by being fixed thereto by means of feet, it being understood that other shapes of the guidance can be considered without departing from the scope of the present invention.

[0011] In the invention, the wedge may be a rigid part, for example substantially cylindrical and slidably mounted in a sheath of the carriage, the part being provided with a part active intended to come into contact with the tread of a wheel of the vehicle to be immobilized. For example, the sheath of the wedge can extend in a direction substantially perpendicular to a direction of longitudinal extension of the guide rail.

[0012] Advantageously, the immobilizer is arranged to cooperate with several locking members, in particular at least two, in particular at least five, or even at least ten adjacent locking members, when it adopts its locked configuration. This improves the resistance of the system against an untimely departure of an immobilized vehicle.

In one embodiment of the invention, the immobilizer is arranged to be driven by the wedge during its movement towards the blocking position to adopt said locked configuration. In this embodiment, the movement of the wedge, under the effect of the second drive device, mechanically causes a movement of the immobilizing device towards its blocking position.

[0014] For example, the immobilizer comprises a movable rod vis-à-vis the carriage and provided at one of its ends with a shoe equipped with at least one complementary member capable of cooperating with a member of lock and at the other of its ends an abutment member adapted to come into contact with the wedge to define the unlocked configuration of the immobilizer, the rod being mounted on the carriage via an elastic return element arranged to return the abutment member towards a rest position defining the locked configuration of the immobilizer. In other words, when the abutment member of the rod is no longer in abutment against the wedge, due to the movement of the wedge towards its blocking position, the elastic return element can then relax to return the abutment member towards its rest position and therefore to cause the shoe to move towards the locking members.

[0015] For example, the elastic return element may comprise a spring compressed between a fixed part of the carriage and between a shoulder of the rod.

[0016] Preferably, the abutment member may include a wheel mounted to rotate on the rod about an axis substantially transverse to the direction of movement of the wedge. The stop member can thus follow, without friction, the movement of the wedge towards its blocking position as far as the end of this wedge or until a change in the surface of the wedge occurs.

Advantageously, the wedge is provided, at its end located on the side of its recessed position, with a sloping flat. This flat allows on the one hand to obtain a quick locking of the carriage on the rail and on the other hand to be able to easily unlock the carriage. This last point can in fact be crucial in the case where the wheel of the vehicle is in pressure against the chock. In this case, it is difficult for the chock to return to its retracted position, due to the stresses that the wheel exerts on it, which thus leads to a breakdown of the system. Thanks to the flat, a slight movement of the cleat towards its retracted position can then cause the shoe to move enough to disengage it from the locking devices and thus allowing the carriage to move on the rail to release the chock from the pressure of the wheel.

In another embodiment of the invention, the system comprising a third drive device capable of causing movement of the immobilizer between its locked configuration and its unlocked configuration. It will be noted that this third drive device makes it possible to unlock the carriage without having to move the stopper. Indeed, in the case where a truck exerts significant pressure on the wedge, this pressure can be taken up on the various elements of the truck and lead to jamming of the immobilizer on the guide rail. It is then impossible to move the chock and the carriage. The fact of dissociating the devices allowing the movement of the wedge, the movement of the carriage and the locking of the carriage thus makes it possible, in the situation mentioned above, to first unlock the carriage in order to then unlock the wedge and thus resolve the problem mentioned.

[0019] For example, the immobilization device may comprise a rod that is movable vis-à-vis the carriage and provided at one of its ends with a shoe equipped with at least one complementary member capable of cooperating with a member lock, the other of its ends being connected to the third drive device. For example, the third drive device may comprise a jack, in particular electric, whose piston is connected to said other end of the rod.

[0020] Preferably, the immobilizer comprises a detector capable of detecting cooperation between the immobilizer and at least one locking member. For example, said detector may be a detector capable of estimating the position, in particular the height, of said shoe with respect to the guide rail, and in particular the locking members. It is indeed possible, when the third drive device moves the immobilizer to its locked configuration, that the position of this immobilizer with respect to the locking members does not allow their cooperation. This is particularly the case when the or each additional member of the sabot is off-axis or offset with respect to the locking member with which it must cooperate, due to an inaccuracy in the movement of the carriage, this additional member coming for example in abutment against the locking member rather than in cooperation with this locking member. The detector thus makes it possible to identify this offset or misalignment in order to correct this inaccuracy of positioning of the carriage. For example, a control unit can be arranged to control the first drive device to cause the carriage to move on the rail, in particular according to a back and forth movement, as a function of the detection operated by this detector.

[0021] Advantageously, the rod comprises a cylinder on which the sabot is fixedly mounted, and in which is slidably mounted a disc connected, directly or indirectly, to the third drive device. If necessary, the rod may include a spring arranged between the cylinder, being compressed between the disc and a cylinder stop, for example formed by a shoulder or a bottom of the cylinder. Following a movement of the carriage coming to realign or realign the or each complementary member of the sabot with a locking member, the spring can then relax in the cylinder, causing a movement of the cylinder so that this complementary member cooperates with the locking device.

Advantageously, the guide rail comprises a rack arranged along the guide rail, each locking member being formed by a notch of said rack. If necessary, the or each complementary member of the sabot may comprise a tooth intended to be engaged in one of the notches of the rack. Advantageously, the first drive device is arranged to drive a pinion meshed with said rack. In this way, the rack contributes on the one hand to the movement of the carriage on the rail and on the other hand to the immobilization of the carriage.

Alternatively, the guide rail may include a transmission chain, for example rigid, extending along the guide rail and connected to the first drive device, each locking member being formed by a link of said transmission channel.

In another embodiment, the locking members are decoupled from the transmission member.

For example, each locking member can be formed by a hole, blind or through, vertical or horizontal, drilled in the guide rail, the holes being regularly spaced along the rail. If necessary, the or each complementary member of the sabot may comprise a pin or a finger intended to be inserted into one of the orifices of the guide rail. [0026] Advantageously, the locking system may comprise an electromechanical device for locking the wedge in its locking position. For example, the electromechanical device may comprise an electromagnet carried by the carriage, the wedge comprising at least one metal portion intended to come face to face with the electromagnet when it adopts its blocking position. Where appropriate, the blocking system may comprise an electromagnet control unit arranged to activate the electromagnet when the chock adopts its locking position, in particular when a detector of the locking system detects that the chock adopts its locking position. blockage. This electromechanical device thus makes it possible to prevent an operator or the driver of an immobilized vehicle from moving the chock towards its retracted position while the vehicle must remain immobilized, which could present a risk for other operators.

In one embodiment of the invention, the first drive device and/or the second drive device comprises an electric motor. For example, the first drive device and/or the second drive device may comprise an electric geared motor, in particular reversible and capable of driving a movement of the carriage, respectively of the wedge, in two opposite directions. As a variant, the first drive device and/or the second drive device may comprise an irreversible electric gear motor. [0028] Preferably, the first drive device and/or the first drive device may comprise a variable speed drive or an electronic regulator of the speed of said electric motor.

[0029] Advantageously, the wedge can be provided, at its end located on the side of its blocking position, with a strut.

[0030] Preferably, the carriage may comprise a first detector capable of detecting the presence of an object in line with a front portion of the carriage and a second detector capable of detecting the presence of an object in line with a portion back of the carriage. If necessary, the blocking system may comprise a control unit arranged to control the first drive device to cause the carriage to move on the rail forwards or backwards depending on the detections made by the front and rear sensors. back. For example, the second detector can be a detector positioned at one end of the carriage and the first detector can be a detector positioned near the wedge or its sheath. If desired, the first detector and/or the second detector may comprise a photoelectric sensor, for example provided with a source of red light or with a laser source.

Optionally, the carriage may comprise two limit sensors each provided at one end of the carriage, the guide rail being provided with two switching elements each provided at one end of the guide rail, each element of switching being capable of causing a switching of one of the end-of-travel sensors when this end-of-travel sensor is positioned in line with this switching element. If necessary, the control unit is arranged to interrupt the movement of the carriage on the rail in response to the switching of a limit switch caused by the passage of this limit switch to the right of an element of commutation. For example, each limit switch may include a magnetic field sensor and each switching element may include a magnet. As a variant, each end-of-travel sensor can include an inductive sensor and each switching element can include a metal spacer.

[0032] Preferably still, the carriage may comprise two end-of-travel sensors each provided at the blocking position and the retracted position of the wedge, the wedge being provided with a switching element, this element of switching being capable of causing a switching of one of the end-of-travel sensors when this end-of-travel sensor is positioned in line with this switching element. If necessary, the control unit is arranged to interrupt the movement of the wedge in response to the switching of a limit switch caused by the passage of the switching element of the wedge to the right of this sensor of limit switch.

[0033] In one embodiment of the invention, the control unit is capable of receiving an instruction for positioning the carriage at the level of a wheel of a vehicle to be blocked. Where appropriate, upon receipt of said instruction, the control unit is arranged to: To. Controlling the first drive device to cause the carriage to move on the rail in a first given direction; b. Following detection, by the second detector, of the presence of an object for a time greater than a first given threshold, controlling the first drive device to cause the carriage to move on the rail in a second direction given, opposite to the first direction; vs. Following the absence of detection, by the first detector, of the presence of an object for a time greater than a second given threshold, controlling the first drive device to interrupt the movement of the carriage on the rail.

For example, the first given threshold can be determined so as to correspond to an uninterrupted detection, by the second detector, of an object during an 8 cm displacement of the carriage in the first given direction, for example towards front of the vehicle. Still for example, the second given threshold can be determined so as to correspond to an absence of uninterrupted detection, by the first detector, of an object during a movement of 4 cm of the carriage in the second given direction, for example towards rear of the vehicle. This ensures that the chock is positioned at the wheel of the vehicle.

If necessary, the control unit can then control the second drive system to cause the wedge to move towards its locking position, then, if necessary, activate the electromechanical device.

The present invention is now described using only illustrative examples and in no way limiting the scope of the invention, and from the accompanying drawings, drawings in which the different figures represent:

[0037] [Fig. 1] represents, schematically and partially, a perspective view of a system for locking a vehicle in front of a loading dock according to one embodiment of the invention;

[0038] [Fig. 2] represents, schematically and partially, a front view of part of the locking system of [Fig. 1];

[0039] [Fig. 3] represents, schematically and partially, a rear view of part of the blocking system of [Fig. 1];

[0040] [Fig. 4] represents, schematically and partially, another rear view of part of the locking system of [Fig. 1];

[0041] [Fig. 5] represents, schematically and partially, another rear view of part of the locking system of [Fig. 1];

[0042] [Fig. 6] represents, schematically and partially, a top view of the blocking system of [Fig. 1] during a stage of its operation;

[0043] [Fig. 7] represents, schematically and partially, a top view of the blocking system of [Fig. 1] during another stage of its operation;

[0044] [Fig. 8] represents, schematically and partially, a top view of the system of blocking of [Fig. 1] during another stage of its operation;

[0045] [Fig. 9] represents, schematically and partially, a top view of the blocking system of [Fig. 1] during another stage of its operation;

[0046] [Fig. 10] represents, schematically and partially, a rear view of part of a locking system according to another embodiment of the invention; And

[0047] [Fig. 11] represents, schematically and partially, a view of the immobilizer of the locking system of [Fig. 10],

In the following description, the identical elements, by structure or by function, appearing in different figures retain, unless otherwise specified, the same references. In addition, the terms "front", "rear" must be interpreted in the context of the orientation of the loading dock as it has been represented, corresponding to the orientation of the movements of a truck with respect to the dock, the truck moving forward to leave the dock, and backing up to approach the dock.

[0049] It has been described in [Fig. 1] a perspective view of a locking system 1 of a vehicle, such as a truck, in front of a loading dock (not shown) according to one embodiment of the invention. In [Fig. 1], the vehicle intended to be immobilized must travel on the left of system 1, reversing towards the farthest end of system 1, so as to position its trailer at the level of the loading dock.

The locking system 1 comprises a guide rail 2, supported by a frame B on which the truck travels, as well as a carriage 3 provided with a cover 31 and mounted movable in translation on the rail 2.

The description of the locking system 1 which will follow refers to [Fig. 1] as well as in [Fig. 2] which represents a front view of the carriage 3, the cover 31 being represented in transparency, and in [Fig. 3] to [Fig. 5] which represent different rear views of the interior of trolley 3.

In the example described, the guide rail 2 extends at a distance from the frame B by being fixed there by means of several feet 21. The guide rail 2 comprises a horizontal rectilinear part extending along an axis X and having an H-section along its entire length. Inside this H-section is provided a rack 22 extending over a major part of the rail 2.

The guide rail 2 also comprises two metal stops 23, each mounted on the straight part and on either side of the rack 22.

The carriage 3 is slidably mounted on the guide rail 2. For this purpose, as shown in [Fig. 2], the carriage 3 comprises a guide part 32, of U-section, mounted on the rail 2 and provided with rollers 32a in contact with the upper surface of the horizontal rectilinear part of the rail 2.

In order to be able to automatically move the carriage 3 at the level of a wheel of a vehicle intended to be immobilized, the carriage 3 is equipped with a first device 4 for driving the carriage 3 in translation on the rail 2 according to the X axis. In the example described, this first drive device 4 comprises a reversible electric gear motor 41 and provided with an electronic speed variator, of which only the gear has been shown in the figures. As shown in [Fig. 3], this geared motor 41 drives a pinion 42 meshed with the rack 22. The geared motor 41 being mounted on the carriage 3, it can therefore cause the carriage 3 to move on the rail 2 forwards or backwards.

The carriage 3 also supports a wedge 5 which can move transversely to the X axis, along a Y axis, between a recessed position (as shown in [Fig. 1] to [Fig. 5]) and a blocking position.

For these purposes, the carriage 3 comprises a sheath 33 in which is slidably mounted a rigid cylindrical part 51 of the wedge 5. This part 51 defines an active part of the wedge 5 provided to come into contact with the tread of a vehicle intended to be immobilized. The wedge 5 also comprises a strut 52, provided at the end of the part 51 on the side of the blocking position. This strut 52 comes to rest on the frame B and in particular makes it possible to prevent a rotation of the wedge 5 and of the whole of the carriage 3 under the force exerted by the wheel of an immobilized vehicle, which could cause a system deterioration 1.

In order to be able to automatically move the wedge 5 from its retracted position to its locking position, or vice versa, the carriage 3 is equipped with a second device 6 for driving the wedge 5 in translation along the Y axis .

In the example described, this first drive device 6 comprises a reversible electric gear motor 61, of which only the gear has been shown in the figures. As shown in [Fig. 4], this geared motor 61 drives a pinion 62 meshed on a rack 53 secured to part 51 of the wedge 5. The geared motor 61 can therefore cause the wedge 5 to move forwards or backwards along the axis Y.

In addition, the carriage 3 comprises a first detector 71, made in the form of a photoelectric sensor 71 provided with a source of red light, and positioned in the vicinity of the sheath 33 of the wedge 5, the cover 31 comprising a hole facing this first detector 71. The carriage 3 also comprises a second detector 72, made in the form of a photoelectric sensor 72 provided with a source of red light, and positioned on the guide piece 32, at a rear end of the carriage 3, the guide piece 32 having a hole facing this second detector 72, below the cover 31.

The carriage 3 comprises a first end-of-travel sensor 73, made in the form of an inductive sensor 73, and positioned on the guide piece 32, at the level of a front end of the carriage 3 and above of the upper surface of the guide rail 2, as well as a second end-of-travel sensor 74, made in the form of an inductive sensor 74, and positioned on the guide piece 32, at the level of a rear end of the carriage 3, next to the second detector 72, and above the upper surface of the guide rail 2. These sensors 73 and 74 are arranged to switch when the carriage 3 passes over one metal bumpers 23.

Finally, the carriage includes a third end-of-travel sensor 75 and a fourth end-of-travel sensor 76, each made in the form of an inductive sensor positioned above the rack 53 of the wedge 5. The rack 53 is equipped with a metal stopper 54 capable of causing a switching of one or the other of these sensors 75 and 76 when the stopper 54 passes under this sensor, due to the movement of the wedge 5.

The operation of the blocking system 1 in response to the detections made by the detectors 71 and 72 and to the switching of the sensors 73 to 76 under the influence of the stops 23 and 54 will be described later.

In order to be able to lock the carriage 3 on the rail 2 in a given position, the carriage 3 comprises an immobilizing device 8, visible in [Fig. 4] and [Fig. 5],

The immobilizer 8 comprises a rod 81 mounted to move in translation with respect to the carriage 3 along an axis Z. This rod 81 is equipped, at its lower end, with a shoe 82 extending under the rack 22 of the guide rail 2. This shoe 82 is provided with a plurality of teeth 82a whose shape is substantially complementary to that of the notches 22a of the rack 22. These notches 22a, in addition to their transmission function allowing the movement of the carriage 3 on the rail 2, form locking members and these teeth 82a form complementary locking members.

[0067] At its upper end, the rod 81 is equipped with a stop member 83, formed by a wheel or a roller coming into contact with a lower surface of the part 51 of the wedge 5.

The immobilizer 8 also comprises a spring 84 compressed between a lower shoulder of a fixed cylinder 34 of the carriage 3 in which the rod 81 slides and an upper shoulder secured to the rod 81.

In other words, when the abutment member 83 is in contact with the lower surface of the part 51, as shown in [Fig. 4] and [Fig. 5], the spring 84 is compressed and the shoe 82 is therefore distant from the rack 22, thus defining an unlocked configuration of the immobilizer 8. In this configuration, nothing opposes the movement of the carriage 3 on the rail 2 .

The part 51 of the wedge 5 is provided, at its end located on the side of the recessed position, with a sloping flat 55 formed on its lower surface.

Thus, when the wedge 5 is driven towards its locking position, the abutment member 83 rolls on the lower surface of the part 51 until it reaches the flat 55, the wedge 5 having then almost reached its position of blockage.

[0072] The abutment member 83 can then move vertically towards a rest position, due to the flat 55 and the relaxation of the spring 84, which then causes a movement of the shoe 82 towards the rack 22, the teeth 82a then meshing with the notches 22a. The immobilizer 8 is then in a locked configuration, the cooperation of the teeth 82a with the notches 22a prohibiting any movement of the carriage 3 on the rail 2, the carriage 3 therefore being immobilized. [0073] When the wedge 5 is driven towards its retracted position, the displacement of the abutment member 83 causes the compression of the spring 84 and the displacement of the shoe 82 out of the rack 22, the immobilizer 8 then returning in its unlocked configuration.

[0074] It is noted on the one hand that the displacement of the wedge 5 towards its blocking position mechanically causes the locking of the immobilizer 8 and therefore the immobilization of the carriage 3, and that conversely, the displacement of the wedge 5 towards its retracted position mechanically causes the unlocking of the immobilizer 8. The geared motors 41 and 61 therefore do not participate in any way in the immobilization of the carriage 3 on the rail.

[0075] On the other hand, due to the sloping flat 55, a slight rearward movement of the wedge 5 from its locking position can make it possible to disengage the shoe 82 from the rack 22, so that it is then possible to move the carriage 3 for example to release the wedge 5 from the pressure exerted by a wheel.

The carriage 3 further comprises an electromagnet 9, mounted above the part 51 of the wedge 5 and allowing, when activated, to lock the wedge 5 in its locking position.

Finally, the carriage 3 comprises a control unit 10 able to receive an instruction to block a vehicle parked on the frame 10 and arranged to control, upon receipt of this instruction and according to the detections made by the detectors 71 and 72 and switches of the sensors 73 to 76, the first and second drive devices 4 and the electromagnet 9.

A mode of operation of the blocking system 1, implemented by the control unit 10, will now be described, in conjunction with [Fig. 6] to [Fig. 9],

[0079] The [Fig. 6] represents a loading dock and a parking area at this loading dock towards which a truck C is reversing in order to be able to carry out transhipment operations between its trailer and the loading dock. The blocking system 1 described in [Fig. 1] to [Fig. 5] is fixed to the frame B of the parking area, the truck backing up along the rail 2 of this system. The carriage 3 is at rest, at a rear end of the rail 2, awaiting the parking of the truck C, and the wedge 5 is in its recessed position.

[0080] As shown in [Fig. 7], once the truck C is parked, the control unit 10 of the truck 3 receives an instruction to block the truck C, and then controls the first drive device 4 to cause the truck 3 to move forward.

[0081] When the rear end of the carriage 3 passes at the level of a rear end of the rear wheel R of the truck C, the second detector 72 detects the presence of this wheel, this detection continuing in an interrupted manner during the movement of the carriage 3. It should be noted that the first detector 71 has passed the front end R of the rear wheel R.

When the time during which the second detector 72 detects the presence of this wheel exceeds a given threshold, corresponding to a movement of the carriage by 8 cm, the control unit 10 then controls the first drive device 4 to drive A displacement of the carriage 3 backwards.

The first detector 71 is then located in front of the front end of the rear wheel R and therefore detects nothing.

When the time during which the first detector 71 detects nothing exceeds a given threshold, corresponding to a movement of the carriage of 4 cm, the control unit 10 then interrupts the movement of the carriage 3, the wedge 5 then being at the front end of the rear wheel R, as shown in [Fig. 8],

[0085] As shown in [Fig. 9], the control unit 10 can then control the second drive device 6 to cause a movement of the wedge 5 towards its locking position, this movement being interrupted when the limit switch sensor 76 switches due to the passage of the bumper 54 under him.

As described above, the movement of the wedge 5 causes the movement of the immobilizer 8 towards its locking position, the carriage 3 thus being locked on the rail 2 and the truck C thus being immobilized.

The control unit 10 can then activate the electromagnet 9 to lock the wedge 5 in its locking position, in order to prevent it from being able to be moved manually.

It should be noted that when the transhipment operations are completed, the control unit 10 then receives an instruction to unlock the truck C and successively controls the electromagnet 9 to unlock it, then the second drive device 6 to bring the wedge 5 back to its retracted position, which causes the unlocking of the immobilizer 8. The movement of the wedge 5 is interrupted when the limit switch 75 switches due to the passage of the stopper 54 under it. The control unit 10 finally controls the first drive device 4 to cause the carriage 3 to move backwards. When the limit switch 74 switches due to the stopper 23 provided at the rear end of the rail 2, the control unit interrupts the movement of the carriage 3 backwards.

[0089] There is shown in [Fig. 10] a carriage 30 of a locking system according to another embodiment of the invention.

[0090] All the elements of this locking system, namely the guide rail 2, its rack 22, the carriage 3, the first drive device 4, the wedge 5, the second drive device 6 and the various sensors are identical to those of the blocking system 1 described in connection with [Fig. 1] to [Fig. 5], with the exception of the immobilizer 80. This immobilizer 80 is also shown alone and in section in [Fig. He],

Similar to the locking system 1, the immobilizer 80 comprises a rod 81 mounted to move in translation relative to the carriage 3 along an axis Z. This rod 81 is equipped, at its end bottom of a shoe 82 extending under the rack 22 of the guide rail 2. This shoe 82 is provided with a plurality of teeth 82a whose shape is substantially complementary to that of the notches 22a of the rack 22. These notches 22a , in addition to their transmission function allowing the movement of the carriage 3 on rail 2, form locking members and these teeth 82a form complementary locking members.

The carriage 3 is equipped with a third drive device 100 connected to the upper end of the rod 81, to cause movement of the immobilizer between an unlocked configuration, in which the shoe 82 is distant from the rack 22 and an unlocked configuration, in which the shoe 82 is moved towards the rack 22, the teeth 82a then meshing with the notches 22a. In the example described, the third drive device 100 is an electric actuator, comprising a cylinder 100a, a piston 100b and an electric motor 100c.

[0093] As shown in [Fig. 11], the rod 81 comprises a cylinder 101 on which is fixedly mounted the shoe 82. This cylinder 101 is slidably mounted in a cylinder 102 of the carriage, fixed vis-à-vis the immobilizer 80. The immobilizer 80 comprises a disc 103, slidably mounted in the cylinder 102, and connected to the piston 100a of the third drive device 100. In the example described, the disc 103 is held by the head of a screw housed in a socket connected to the plunger 100a.

A spring 104 is arranged in the cylinder 102, between the disc 103 and the bottom of the cylinder 102.

The immobilizer 80 comprises a detector (not shown) capable of evaluating the position of the shoe 82 with respect to the rack 22, and thus of detecting whether the immobilizer is in its locked configuration or in its unlocked configuration.

It will be noted that when the third drive device 100 moves the immobilizer 80 towards its locked configuration, it is possible that the teeth 82a of the shoe 82 are offset with respect to the notches 22a of the rack 22 , due to an inaccuracy during the movement of the carriage 3. Consequently, the teeth 82a come into abutment against the teeth of the rack 22, instead of meshing in the notches 22a, which makes it impossible to lock the carriage 3 on the rail 2. In this case, the piston 100a still continues its movement, causing a displacement of the disc 103 in the cylinder 102, the latter remaining fixed due to the abutment of the teeth 82a against the rack 22. The spring 104 is then compressed between disc 103 and the bottom of cylinder 102.

The immobilizer detector 80 then detects that the immobilizer 80 remains in its unlocked configuration, despite the actuation of the third drive device 100.

The control unit 10 can then control the first drive device 4 to cause a brief movement of the carriage 3, in order to cause a slight round trip of the carriage 3 around its position. This movement then causes a realignment of the teeth 82a with the notches 22a. Cylinder 102 is then free to move and spring 104 can then relax, automatically causing teeth 82a to engage in notches 22a.

The foregoing description makes it possible to understand that, thanks to the invention and in particular thanks to a device for immobilizing a carriage which locks and unlocks on the transmission elements of the carriage on the guide rail, it is conceivable to use, to produce the drive devices for the carriage and the wedge , electric motors or any other type of motor developing less power than that developed by a hydraulic system.

In any event, the invention cannot be limited to the embodiments specifically described in this document, and extends in particular to all equivalent means and to any technically effective combination of these means. One could in particular consider other types of means for locking the immobilizer on the rail, and in particular holes drilled in the rail intended to receive locking fingers of the immobilizer. It is also possible to envisage other modes of transmission allowing movement of the carriage on the rail and in particular the use of a transmission chain, a belt or an endless screw, the locking members being able to be formed on this transmission element or on the contrary be decoupled from this transmission element.

Claims

[Claim 1] Locking system (1) of a vehicle (C) in front of a loading dock, the system comprising a guide rail (2), a carriage (3, 30) mounted in translation on the guide rail , a first drive device (4) in translation of the carriage on the rail, a wedge (5) mounted in translation on the carriage in a direction transverse to the guide rail, a second drive device (6) in translation of the chock capable of causing movement of the chock on the carriage between a blocking position and a retracted position, characterized in that the guide rail comprises a plurality of locking members (22a) arranged along the guide and a mobile immobilizing device (8, 80) carried by the carriage and capable of taking a locked configuration in which it cooperates with at least one of the locking members to immobilize the carriage on the rail and an unlocked configuration, and that the guide rail (2) comprises a transmission member (22), the first drive device (4) being arranged to cooperate with said transmission member to cause a translational movement of the carriage (3) on the rail (2) and in which the locking members (22a) are formed by the transmission member.

[Claim 2] Locking system (1) according to the preceding claim, in which the immobilizing device (8, 80) is arranged to cooperate with several locking members (22a) when it assumes its locked configuration.

[Claim 3] Locking system (1) according to one of the preceding claims, characterized in that the immobilizing device (8) is arranged to be driven by the wedge (5) during its movement towards the blocking position for adopt said locked configuration.

[Claim 4] Locking system (1) according to one of the preceding claims, in which the immobilizing device (8) comprises a rod (81) movable with respect to the carriage and provided at one of its ends of a sabot (82) equipped with at least one complementary member (82a) capable of cooperating with a locking member (22a) and at the other of its ends with an abutment member (83) capable of coming in contact with the wedge (5) to define the unlocked configuration of the immobilizer, the rod being mounted on the carriage (3) via an elastic return element (84) arranged to return the abutment member to a position of rest defining the locked configuration of the immobilizer.

[Claim 5] Locking system (1) according to claim 3, wherein the wedge (5) is provided, at its end located on the side of its recessed position, with a sloping flat (55).

[Claim 6] Locking system (1) according to one of the preceding claims, the system comprising a third drive device (100) capable of driving a moving the immobilizer (80) between its locked configuration and its unlocked configuration.

[Claim 7] Locking system (1) according to one of the preceding claims, in which the guide rail (2) comprises a rack (22) arranged along the guide rail and in which each locking member (22a) is formed by a notch of said rack.

[Claim 8] Locking system (1) according to one of the preceding claims, characterized in that it comprises an electromechanical device (9) for locking the wedge (5) in its locking position.

[Claim 9] Locking system (1) according to one of the preceding claims, in which the first drive device (4) and/or the second drive device (6) comprises an electric motor.

[Claim 10] Locking system (1) according to the preceding claim, in which the first drive device (4) and/or the first drive device (6) comprises an electronic variable speed drive of said electric motor.

[Claim 11] Locking system (1) according to one of the preceding claims, in which the carriage (3) comprises a first detector (71) capable of detecting the presence of an object (R) in line with a portion front of the carriage and a second detector (72) capable of detecting the presence of an object in line with a rear portion of the carriage, the system comprises a control unit (10) arranged to control the first drive device (4 ) to cause the carriage to move on the rail (2) forwards or backwards depending on the detections made by the first and second detectors.

[Claim 12] Locking system (1) according to the preceding claim, in which the control unit (10) is adapted to receive an instruction for positioning the carriage (3) at the level of a wheel (R) of a vehicle (C) to be blocked, and in which, upon receipt of said instruction, the control unit is arranged to: a. Controlling the first drive device (4) to cause the carriage to move on the rail (2) in a first given direction; b. Following detection, by the second detector (72), of the presence of an object for a time greater than a first given threshold, controlling the first drive device to cause the carriage to move on the rail in a given second direction, opposite to the first direction; vs. Following the absence of detection, by the first detector (71), of the presence of an object for a time greater than a second given threshold, controlling the first drive device to interrupt the movement of the carriage on the rail.