FR3045588A1 - ANTI-PACKING DEVICE AND LIFTING APPARATUS EQUIPPED WITH SUCH A DEVICE. - Google Patents

Abstract

The invention relates to an anti-runaway device comprising: - a rotation shaft (20), - a brake with a rotating brake member (22) rotationally integral with the rotation shaft, and at least one pivoting brake member ( 32a, 32b), the pivoting brake member having a pivoting freedom between a resting position of the rotating brake member and a braking position, in which it is engaged with the rotating brake member, - a spring of return (44) of the pivoting brake member in the braking position, - a retaining trigger (36) of the pivoting brake member in the rest position, - a brake release mechanism (60), integral in rotation of the rotation shaft. The invention has applications in the manufacture and securing of rotating machinery and in particular lifting equipment.

Description

Anti-embalming device and lifting device equipped with such a device

Technical area

The present invention relates to an anti-embalement device and in particular an anti-runaway device for a rotating machine. The term "rotary machine" means a machine or equipment comprising one or more rotary members. The anti-embalement device aims to prohibit an excessive speed of rotation of a rotating machine or an organ of such a machine. By extension, the anti-runaway device also makes it possible to prohibit excessive linear speed when the movement of the rotating machine is transformed into linear movement, for example by means of a flexible link. The invention finds applications in particular in the fields of manufacturing and securing winches, lifting devices, lifts, elevators, pulleys, return drums and winding drums.

State of the art

An anti-runaway device adapted to a hoisting apparatus, or drum, is known, for example, from WO2011 / 104650, DE20 2007 002 787 and FR3013341. These documents provide a lock provided with a locking member engaging with a stopper wheel to block the rotation of the lockwheel. Locking of the locking wheel immobilizes a drum integral in rotation with this wheel. The latch, controlled by a cam and roller mechanism, is configured to cause the drum to become stationary when its rotational speed becomes excessive.

Such a device, particularly adapted to prevent the fall of a load suspended from a hoist, however, has a certain complexity. In addition, it is found that some parts are constantly subject to movement during normal operation of the hoist. This is the case, in particular, of the cam and roller mechanism. It is subjected to an oscillating movement accompanying the rotation of the drum.

The presence of moving parts due to the normal operation of the lifting device causes wear of these parts and a certain sensitivity to soiling. Periodic maintenance and cleaning operations are thus necessary to guarantee reliable operation of the anti-runaway device and also to prevent its inadvertent activation. In addition, the moving parts of the control mechanism have a durability, and an ability to age, generally lower than other organs of the hoist, and must be verified and replaced in a timely manner.

Presentation of the invention

For the purposes of the invention, anti-runaway device means a device that makes it possible to oppose the operation of a machine in an excessive regime. The excessive speed generally corresponds to a rotational speed or an excessive linear speed of one or more members of the machine, or members driven in motion by the machine. The anti-runaway device can act on the movement of the machine either by blocking the movement or by slowing the movement, or by stabilizing the movement.

The particularity of the anti-runaway device of the invention is its threshold triggering. In other words, the anti-runaway device is active only if the speed of the machine is excessive, that is to say if it is greater than a predefined setpoint. The object of the invention is to propose an anti-runaway device, simple and reliable, which is not very sensitive to aging and which requires only a summary maintenance and of long periodicity.

One aim is in particular to propose such a device with a control mechanism that is not oscillating.

Another aim is to propose an anti-runaway device and in particular a fall arrest device, for a lifting device with an improved load capacity.

Another object of the invention is to propose an anti-packaging device that is silent when it is not triggered.

To achieve these aims, the invention proposes an anti-packaging device comprising: - a rotating shaft and a fixed support, - a brake with a rotating brake member integral in rotation with the rotation shaft, and at least one brake member pivoting, secured to the fixed support, the pivoting brake member having a pivotal freedom relative to the fixed support between a rest position remote from the rotating brake member and a braking position, wherein the pivoting brake member is engaged with the rotating brake member, - a return spring of the brake member pivoting in the braking position, - a trigger for retaining the pivoting brake member in the rest position, - a mechanism triggering the brake, centrifugal effect, the trigger mechanism being integral in rotation with the rotation shaft and comprising at least one driver with a freedom of movement between a retracted position distant from the a restraining trigger, and an extended position of release of the retaining trigger.

In the deployed position, the trainer is sufficiently close to the restraining trigger to engage the retaining trigger under the effect of rotation. He can then release the retaining trigger by training. This operation is described in more detail in the following description.

The anti-runaway device can be associated with a machine simply by making the rotation shaft integral with the movement of the machine. In the particular case of a rotating machine, the rotating machine and the anti-runaway device can share the same rotation shaft, or have separate rotation shafts but coupled in rotation. The rotation shaft of the anti-runaway device causes rotation of the brake release mechanism. This mechanism, centrifugal effect, can be mounted directly on the rotation shaft of the device or be coupled to this shaft. When the release mechanism is coupled to the rotation shaft, for example by a set of gears, it is possible to give it a rotation speed different from that of the rotation shaft, and in particular a rotational speed. higher to increase sensitivity.

The rotation of the brake release mechanism has the effect of subjecting the driver of this mechanism to a centrifugal force proportional to the speed of rotation, and more precisely, proportional to the square of the speed of rotation.

When the rotation speed is low, and in particular below a set speed, the centrifugal force is insufficient to move the driver, and at least insufficient to reach the retaining trigger. The pivoting brake member retained by the retaining trigger then remains in its rest position. In this position, the anti-packaging device does not hinder the movement of the machine with which it is associated.

On the other hand, when the rotation speed becomes equal to or greater than a set speed, the centrifugal force is sufficient to move the trainer and make it reach the retaining trigger. The trainer then actuates the trigger, moving it, and in particular by turning it.

The displacement of the retaining trigger has the effect of releasing it, it also has the effect of releasing the pivoting brake member of the retaining force exerted by the trigger on this body. The pivoting brake member then moves immediately from the rest position to the braking position under the effect of the return spring. In the braking position the pivoting brake member contributes to slowing down or stopping the rotation of the rotation shaft as described below.

After the release of the brake, it is possible to reset it, after having discarded the cause of the runaway. The reset is essentially to move the pivoting brake member in the rest position and return the trigger in a holding position of the dormant brake member. The reset is preferably a manual operation.

According to a preferred embodiment of the brake release mechanism, this mechanism may include a return spring of the driver in the retracted position. In this case, the return spring has sufficient stiffness to keep the driver away from the release position of the retaining trigger when a rotation speed of the rotating shaft is lower than the target speed. The return spring exerts on the driver a force which opposes the centrifugal force. The use of such a spring makes it possible to easily adjust the trigger threshold of the device, and therefore the set speed, by acting on its stiffness. The stiffness of the restoring spring of the trainer then conditions the centrifugal force necessary to overcome the restoring force that it exerts, and thus the set rotational speed for triggering the release mechanism.

One embodiment of the release mechanism without return spring can be envisaged, for example, by keeping the driver in its retracted position by gravity or friction. Such an embodiment is however less reliable than that implementing a return spring of the trainer. The return spring may be a coil spring, or a leaf spring, for example.

According to one particular embodiment, the release mechanism of the trigger may comprise a wheel integral in rotation with the rotating machine shaft, and the return spring may comprise one or more flexible blades connecting one or more drivers to the wheel. to the coach. The spring blades are preferably steel blades screwed onto the wheel.

The flexible blades can be bent to conform to the perimeter of the release mechanism wheel when the wheel is at rest. Other forms of spring or spring materials may be retained as their configuration generates a biasing force opposing the centrifugal force.

The anti-runaway device brake of the invention can be a static brake. For the purposes of the invention, the term "static brake" is understood to mean a brake which abruptly blocks the rotational movement of the axis of rotation when the pivoting brake member and the rotating brake member come into engagement.

The brake can also be a dynamic brake. For the purposes of the invention, the term "dynamic brake" is understood to mean a brake which slows down the rotational movement of the axis of rotation when the pivoting brake member and the rotating brake member come into engagement.

In a "static brake" configuration, the pivoting brake member may comprise at least one stop and the rotating brake member may comprise at least one stop forming abutment. The abutment bears in complementarity of form against the stop in the braking position. This causes an almost immediate and sudden stop of the rotation. Several stops cooperating with several stoppers can be provided for a distribution of the blocking stress. The rotating brake member may be formed, for example, by a notched plate, a gear wheel, or a simple rotating bar. The ends of the bar, the teeth of the wheel or the notches of the plate are respectively the stoppers.

According to a preferred embodiment, the pivoting brake member may comprise an end with a retaining appendage configured to bear against the retaining trigger in the rest position. The pivoting brake member may also include a biocage finger, pivotally integral with the retaining appendage, and whose end forms a stop. In this case it is possible to separately optimize the two ends for their retaining function and their stop function.

In a dynamic brake device configuration, the brake may be, for example, one of a shoe brake, a belt brake, a drum brake, and a magnetic brake.

The function of the brake is then to gradually dissipate the rotational energy, by friction or induction, and to slow down the movement of the machine provided with the anti-runaway device. Depending on the intensity of the dynamic braking, the release of the brake causes a simple slowing down or a complete stop of the movement. The stop is not, however, a stop as abrupt as that caused by a static brake and the braking constraints are also lower than those of the static brake.

Thus, an anti-runaway device with a dynamic brake, when used for a hoist, allows, for equal space, to secure heavier loads. It also allows, for a given load to consider higher trigger speeds, and therefore faster displacement of loads in normal use.

In the "dynamic brake" embodiment, the rotating brake member may comprise, for example, one of a wheel and a brake drum, and the pivoting brake member may comprise one of a shoe , a clamping band, a magnet and a pad, coming into contact with the brake drum, respectively against the brake wheel, in the braking position.

In particular a clamping band, a shoe or a pad can come rub against the brake drum. The friction force, and the braking efficiency can be adjusted by the choice of materials forming the friction pads in contact, by the choice of the contact surface, and by the stiffness of the return spring which engages the pivoting brake member with the rotating brake member. Another object of the invention is to propose a lifting apparatus using an anti-runaway device as described above.

In particular one goal is to provide such a lifting device usable regardless of the lifting height. The invention proposes for this purpose a lifting device comprising: - at least one lifting drum and - an anti-runaway device as described above.

The lifting drum is integral in rotation with the rotation shaft of the anti-runaway device.

The lifting drum is likely to intervene in lifting, lowering, but also more generally the movement of loads, such as, for example, sets of a theater. It may be in particular a winding drum or a return drum. The hoist may in fact further comprise one or more flexible links such as a cable, a rope, a rope, a strap or a chain, which are wound on the drum or are simply returned by the drum .

When the drum is used as a return drum, the flexible link wraps around it only for a fraction of a turn or a very limited number of turns. The lifting drum may in particular be a return drum of a multi-strand apparatus comprising a plurality of flexible links. In a more basic embodiment, the lifting drum can be summed up as a simple grooved wheel.

In the case of a winding drum, the hoist is akin to a winch.

The lifting drum can be mounted on the rotation shaft of the anti-runaway device. It can also be mounted on a separate shaft but cut in rotation with the anti-runaway shaft. The rotating brake member, for example the brake drum or the slotted plate can be mounted directly against a flange of a winding drum of the lifting mechanism.

In a particular embodiment of the lifting device, the lifting drum, or at least a portion of the lifting drum, may form the rotating brake member of the anti-runaway device. In this case the pivoting brake member can engage the lifting drum in the braking position.

The lifting drum may have, for example, a flange with suitable retainers. According to another possibility, corresponding to the "dynamic" brake all or part of the lifting drum can form the brake drum described above. In this case, the pivoting brake member comprises a shoe, a shoe, a magnet or a band, which can be pressed against the lifting drum. The pivoting brake member may for example be pressed against an enlarged flange of the lifting drum forming the brake drum.

Finally, the anti-runaway device may comprise a pivoting brake member which comes into direct contact with a flexible link, for example a cable of the hoisting apparatus. For example, the pivoting brake member may comprise a pad capable of gripping the flexible link against the lifting drum. This last implementation is particularly suitable when the flexible link, for example a cable, passes over the hoist drum used as a return drum. Squeezing the flexible link against the drum avoids inadvertent sliding of the flexible link relative to the drum when the drum is braked by the anti-packaging device.

When the anti-runaway device is at rest, the absence of oscillating parts makes it particularly silent. This feature is useful in hoist applications in a context such as a theater. Moreover, unlike traditional fall arrest devices, the anti-runaway device can be implemented for any lifting height without increasing its size.

The anti-runaway device by prohibiting rotation of the drum or throat wheel at an excessive speed also makes it possible to avoid excessive linear speed of a load retained by the flexible link or suspended from the flexible link. The anti-runaway device can thus be used as a fall arrest device for the load. Depending on the applications, the device may also be shaped to prevent lifting of a load with excessive speed. Other features and advantages of the invention emerge from the description which follows, with reference to the figures of the drawings. This description is given for purely illustrative and non-limiting purposes.

Brief description of the figures

Figure 1 is a perspective of an anti-runaway device according to the invention with pivoting brake members in a rest position.

FIG. 2 is a front view of the device of FIG.

Figure 3 is a rear view of the device of Figure 1.

FIG. 4 is a detailed view of the device of FIG. 1.

Figure 5 is a perspective of the device of Figure 1 with pivoting brake members in a braking position, engaged with a rotating brake member.

FIG. 6 is a perspective of an anti-runaway device constituting a variant of the device of FIG. 1.

Figure 7 is a schematic representation of a hoist using an anti-runaway device according to the invention.

Detailed description of modes of implementation of the invention.

In the following description, identical, similar or equivalent parts of the different figures are indicated with the same references so that they can easily be referenced from one figure to another.

The figures are represented in free scale.

Figure 1 shows an anti-runaway device 10 usable for a rotating machine. The anti-runaway device 10 comprises a rotation shaft 20 integral in rotation with at least one rotating member of the rotating machine. By way of example, in the case of a hoisting apparatus, a winding drum can be mounted on the rotation shaft 20. The rotating shaft 20 receives a rotating brake member in the form of a notched plate 22. The notched plate is mounted on the rotational shaft 20 so as to align an axis of symmetry of the plate with the axis of the shaft. It is integral in rotation with the rotation shaft 20.

The anti-runaway device also comprises a fixed support 30. In the illustrated example, it is a metal plate having a slot 31 for passing through the rotation shaft 20. The fixed support 30 is preferably mounted on a frame of the rotating machine or on a supporting structure of the rotating machine. It is dimensioned so as to withstand the braking constraints of the rotating machine without moving and without deforming.

In the example illustrated in Figures 1, 2, 5 and 6, the fixed support receives two pivoting brake members 32a, 32b. Each pivoting brake member is mounted on a pivot pin 34a, 34b which allows it to pivot from a rest position, shown in FIGS. 1, 2 and 6, and a braking position shown in FIG.

It can be seen in Figures 1 and 2 that in the rest position the pivoting brake members 32a, 32b are spaced from the notched plate 22. The holding of the pivoting brake members in the rest position is ensured by a trigger of retainer 36 which cooperates with a retaining appendage 38 of the first pivoting brake member 32a. More specifically, the trigger has a shoulder 40 which cooperates with a complementary shoulder 42 of the retaining appendage 38 of the first pivoting brake member 32a to retain it against a restoring force exerted by a spring. recall 44. The return spring 44, better visible in Figure 3, is located at the rear of the fixed support 30.

The shoulders 40, 42 of the trigger and the first pivoting brake member 32a are visible in Figure 4 which shows, on a larger scale, part of the anti-runaway device.

As shown in Figure 3, which is a rear view of the device, the two pivoting brake members 32a and 32b are interconnected by a cam system 46a, 46b and rod 48, which makes them integral pivotally. It is also observed that the return spring 44, common to the two pivoting brake members 34a, 34b, is a helical spring operating in tension and arranged between the link 48 and a fastener 50 of the fixed support 30.

The return spring exerts on the pivoting brake members 32a, 32b a force tending to approach a locking pin 52a, 52b of these members of the notched plate. The locking fingers each have an end forming a stop 54a, 54b as shown in FIGS. 1 and 2. The stops are shaped to bear against stoppers 56 formed by abutments at right angles to the notches of the notched plate 22. The pivoting of the pivoting brake members 32a, 32b, which makes contact with the stops and the abutments, is triggered by a trigger mechanism 60 with a threshold.

As shown again in FIGS. 1 and 2, the threshold triggering mechanism 60 comprises a wheel 62 provided with two trainers 64. The trainers are in the form of small cleats. They are connected to the wheel 62 by steel blades 66 forming a spring. More specifically, the drivers 64 are each integral with a free end of a blade whose shape follows the periphery of the wheel 62. A proximal end of the blades, opposite the free end, is fixed to the wheel, for example by screwing. The spring blades 66 exert a restoring force on the drivers which tends to bring them closer to the periphery of the wheel 62.

When the rotation shaft 20 is rotated, the wheel 62, secured to the rotation shaft also begins to rotate. The drivers 64 are subjected to a centrifugal force, depending on the speed of rotation, the radius of the wheel 62 and their mass. The centrifugal force is contained by the return force of the blades 66. However, a growing rotational speed causes the drivers to disengage from the peripheral surface of the wheel 62.

It should be noted that in Figure 1, the drivers 64 and the leaf springs 66 are shown peeled off the wheel 62 so as to make them more visible. This corresponds to a position occupied by the drivers 64 when the rotational speed of the wheel 62 is not zero but still insufficient for the trainers to reach the retaining trigger 36. When the rotational speed of the wheel 62 is zero, the Spring blades can bring the coaches 64 back against the wheel 62.

When the rotational speed of the rotation shaft 20 and the wheel 62 reaches or exceeds a set point, the drivers 64 are sufficiently spaced from the wheel to reach the retaining trigger 36. As shown in FIG. Trainer 64 sufficiently raised from the wheel 62 by centrifugal force engages with the retaining trigger 36.

When the driver is engaged with the retaining trigger 36, the movement of the wheel 62 causes the retaining trigger to pivot or move and release the retaining appendage 38 from the first pivoting brake member 32a. Figure 4 shows the retaining trigger 36 and the retaining appendage 38 of the first pivoting brake member 32a just as they are released. Continuing its rotation with the wheel 62, the driver 64 separates from the retaining trigger that has rotated. This avoids a mechanical stress on the retaining trigger or the trainer that is greater than that required for the release of the retaining trigger. As soon as the retaining appendage 38 of the first pivoting brake member 32a is released from the retaining trigger 38, the two pivoting brake members 32a, 32b pivot together. The stops 54a, 54b of the locking fingers 52a, 52b are wedged in the notches and against the stops 56 of the notched plate 22. The braking position, where the brake is engaged, is shown in FIG. this position, the notch plate is immobilized. However, as the notched plate is integral in rotation with the rotation shaft 20, the rotation of said shaft and that of all the other members integral in rotation with the shaft is stopped. In particular, the movement of a rotating machine, not shown, integral in rotation with the rotation shaft 20 is stopped. This stop, abrupt, thus puts an end to runaway of the machine which led to a rotation of the shaft at a speed equal to or greater than a set speed for the triggering of the anti-runaway device. The set speed can be fixed in particular by the length or the stiffness of the leaf springs 66.

FIG. 6 shows another possible embodiment of an anti-runaway device according to the invention using a "dynamic" brake. The device of FIG. 6 shares a large number of members with the devices of FIGS. 1 to 5 and their description is not repeated here.

The notched wheel of the device of FIGS. 1 to 5 is replaced by a braking drum 24 on the device of FIG. 6. The braking drum 24 is integral in rotation with the rotation shaft 20. rotating brake. The pivoting brake members 32a, 32b are no longer provided with an abutment but have an end equipped respectively with a brake shoe 56a, 56b.

In the rest position of the pivoting brake members 32a, 32b, the braking shoes 56a, 56b are spaced from the braking drum. Conversely, in the braking position, resulting from the triggering of the triggering mechanism 60, the braking shoes 56a, 56b are pressed against the brake drum 24 under the effect of the return spring 44. When the braking shoes are applied against the drum, they rub on the drum and dissipate all or part of the rotational energy. This results in a slowdown or a progressive stop of the rotation which puts an end to the runaway.

Any stopping of the rotation caused by the "dynamic" brake of the device of FIG. 6 is less abrupt than the blocking stop caused by the "static" brake of the preceding figures.

It can be seen in FIG. 6 that the device comprises two retained tumblers 36a, 36b, instead of just one. A trigger is associated respectively with each pivoting brake member 32a, 32b. Furthermore, each pivoting brake member is configured at right angle or elbow with a retaining appendix 38a, 38b capable of cooperating with the corresponding retaining trigger 36a, 36b and with an arm respectively carrying the braking shoe 56a, 56b.

In Figure 6, the drivers of the trigger mechanism 60 are shown in a fully retracted position, occupied, for example, at the device stop.

Figure 7 shows a lifting device equipped with an anti-wrapping device 10 according to the invention used as a fall arrest device. The hoist comprises a motor assembly 2, and a winding drum 4 having a rotation shaft 20 common with the anti-runaway device 10. The drum receives a cable 6. Bearings 8 of the shaft support rotation 20 are mounted on a supporting structure 9 on which are also anchored the motor assembly 2 and anti-packaging device 10. The carrier structure 9 is, for example, a beam of a gantry.

In Figure 7 the anti-runaway device is symbolically represented without indicating details. This is, for example, a device comparable to that illustrated by the previous figures. According to another embodiment, the fixed frame of the anti-runaway device can serve to compensate for the drum. The drum, or another member of a rotating machine, can be mounted directly on the wheel of the centrifugal mechanism, or on the rotating brake member, that is to say on the brake drum or the slotted plate .

In particular the drum can be fixed to tenons 70 of the wheel 62, visible in FIGS. 1, 2, 4, 5 and 6.

The anti-runaway device prevents an excessive rotation speed of the drum and thus a fall of a load that would be raised by the drum cable.

Claims (12)

1) anti-runaway device comprising: - a rotation shaft (20) and a fixed support (30), - a brake with a rotating brake member (22, 24) integral in rotation with the rotation shaft, and at least one pivoting brake member (32a, 32b) integral with the fixed support, the pivoting brake member having a pivoting freedom relative to the fixed support between a rest position remote from the rotating brake member and a position of braking, in which the pivoting brake member is engaged with the rotating brake member; - a return spring (44) of the brake member pivoting in the braking position; - a trigger (36, 36a, 36b) for retaining the pivoting brake member in the rest position, - a trigger mechanism (60) for the brake, with centrifugal effect, the triggering mechanism (60) being integral in rotation with the rotation shaft, and comprising at least one driver (64) with freedom of movement e a retracted position remote from the retaining trigger, and an extended release position of the retaining trigger. 2) Device according to claim 1, wherein the trigger mechanism (60) comprises at least one return spring (66) of the driver (64) in your retracted position, the spring having sufficient stiffness to maintain the coach (64) away from the trigger release position when a rotational speed of the rotating shaft is less than a set speed. 3) Device according to claim 2, wherein the triggering mechanism (60) comprises a wheel (62) integral in rotation with the rotation shaft (20), and wherein the return spring of the trainer comprises a blade flexible (66) connecting the wheel (62) to the driver (64). 4) Device according to one of claims 1 to 3, wherein the pivoting brake member comprises at least one stop (54a, 54b) and wherein the rotating brake member (22) comprises at least stop (56), the abutment bearing in complementarity of form against the stop in the braking position. 5) Device according to claim 4, wherein the rotating brake member comprises one of a slotted plate, a toothed wheel and a rotating bar. 6) Device according to one of claims 4 or 5, wherein the pivoting brake member comprises a retaining appendix (58, 58a, 58b) configured to abut on the retaining trigger (36, 36a, 36b). in the rest position, and a locking finger (52a, 52b) having the stop (54a, 54b). 7) Device according to claim 1, wherein the brake is one of a shoe brake, a belt brake, a drum brake, and a magnetic brake. 8) Device according to claim 7, wherein the rotating brake member comprises one of a brake wheel and a brake drum (24), and wherein the pivoting brake member comprises one of a shoe ( 58a, 58b), a strip, a magnet and a braking pad, coming into contact with the braking drum (24), respectively against the braking wheel, in the braking position. 9) Lifting apparatus comprising: a lifting drum (4) and an anti-runaway device (10) according to any one of the preceding claims, wherein the lifting drum (4) is integral in rotation with the shaft of rotation (20) of the anti-runaway device. Lifting apparatus according to claim 9, further comprising at least one flexible link (6), and wherein the lifting drum (4) is one of a return drum and a winding drum of the flexible link. (6). 11) Lifting apparatus according to one of claims 9 or 10, wherein the lifting drum forms the rotating brake member of the anti-runaway device. 12) Lifting apparatus according to claim 10, wherein the anti-runaway device comprises a pivoting brake member engaging the flexible link (6) in the braking position.