EP0542340B1 - Winder with pull-back spring and controllable locking device - Google Patents

Description

The subject of the present invention is a reel comprising a winding drum mounted to rotate in a support structure, a return spring of the winding drum, and a controllable blocking device for the winding drum comprising a crown with internal toothing. , connected to the winding drum.

The reels are widely used to contain electric cables, flexible hoses or other flexible members, which are wound inside the reel, can be pulled out and, in cases where the reel is provided with 'a return spring, can be rewound in the reel by the action of the spring which is included therein, which is charged by effect of the extraction of the flexible member and then controls the rewinding. In their simplest forms, these reels hold the flexible member which has been extracted therefrom under permanent tension, and then they recall it as the traction exerted on this flexible member is released. However, this behavior is appropriate for certain applications, while for other applications it is required that the extracted flexible member is not recalled, even if the traction exerted on it ends, and this until one does not gives a special command to cause the winding.

By the document "Western Electric - Technical Digest - No. 56, October 1979 pages 5-6 - RS Brown et al: Cord Reel Latch Mechanism" we know a reel according to the preamble of claim 1, in which the winding is prevented by a blocking device and it is started by a short successive action of extraction of the flexible member, having the effect of releasing the blocking device. The user is warned of the release of the blocking by a trigger.

In some cases winders of this kind can be dangerous, because the short successive action of extraction can be accidental and cause unwanted and untimely winding, all the more so since, under certain conditions, an extremely reduced traction is sufficient to release the blockage. The trigger that warns of the establishment of the winding condition can easily go unnoticed in a noisy environment.

In addition, in any case, the reels of known types have a pre-established behavior which can in no way be modified when the application requirements of the reel are modified.

The main object of the present invention is to propose a blocking device for a reel with return spring, which must exhibit the behavior described above while requiring, for the release, the extraction of a relatively large length of the flexible member. , which is sufficient to exclude, for almost all accidental actions, the possibility of causing an untimely release, while means must be provided to surely avoid the impossibility of a successive extraction sufficient to cause the voluntary release of the blockage .

In addition, according to a preferred development, another object of the invention is to provide the reel with a control selector making it possible to modify at will the behavior of the reel, by replacing the behavior described, which consists of a blocking and an alternating activation of the winding, a behavior which consists in the continuous rewinding of the flexible member, or even a behavior which consists in the absence of any rewinding until an action to this effect does not is successively performed on the command selector; so that the reel can be adjusted to take account of different application conditions.

The main object of the invention is achieved by a reel according to the characterizing part of claim 1.

As will be described in detail below, due to all of these characteristics, the take-up drum, connected to said crown with internal teeth, allows the extraction of a flexible member wound on the drum, but, when the extraction ends, it cannot rewind under the action of the return spring, because it is stopped by the blocking member. But if a successive extraction is made of a length which corresponds to at least half of the perimeter of the blocking member, the latter reverses its position, after which it no longer opposes rewinding, which is therefore carried out by the return spring, and this until the complete winding or until, by a subsequent extraction of the flexible member, the position of the locking member is again reversed. However, the action of the blocking member cannot be exerted when it is in correspondence with the arc of inactivity of the crown with internal teeth, along which the teeth extend only over part of its thickness. Therefore, by adequately establishing the length of this arc of inactivity of the ring gear, as well as its position relative to the point at which the flexible member is anchored to the winding drum, it can be ensured that the blocking can never take place when the length of the flexible member still received in the reel is less than half the perimeter of the blocking member, so that the possibility that a successive extraction, necessary to voluntarily release the blockage, be prevented.

According to a further development of the invention, the device further comprises a stop member capable of being moved by a control selector between a position in which it does not interfere with the movement of the blocking member, and a position in which it stops the blocking member during its movement, preventing the reversal of its position.

When the control selector is moved so that said stop member does not interfere with the movement of the locking member, the alternating operation described above is observed. When, on the contrary, the control selector is moved so that said stop member prevents the reversal of the position of the blocking member, two different situations can be checked which are prolonged until the control selector will only be moved in the opposite direction. If the locking member was in the locking position when the control selector was moved, the reel will then allow the flexible member it contains to be extracted, but it will never be able to rewind. If, on the contrary, during the movement of the control selector the blocking member was in the released position, the reel will then authorize the extraction of the flexible member which it contains, but it will be able to rewind it as and as the traction exerted on the flexible member is released. In this way the reel has the possibility of explaining, according to the desire of the user, three different behaviors, and it can be adapted each time to the requirements of any particular application.

• Fig. 1 montre un enrouleur suivant l'invention vu en élévation latérale, à une échelle réduite et avec une partie de l'enveloppe enlevée;
• Fig. 2 montre, vu du côté opposé à celui de la figure 1, le dispositif de blocage relié au tambour d'enroulement, en une condition fondamentale de fonctionnement;
• Fig. 3 montre d'une façon semblable a la figure 2 le dispositif de blocage en une autre condition fundamentale de fonctionnement;
• Figs. 4 et 5 sont des vues partielles qui montrent des positions intermédiaires pendant le passage du dispositif de blocage de la condition de la figure 2 à la condition de la figure 3;
• Fig. 6 montre une condition d'arrêt du dispositif de blocage;
• Fig. 7 montre à une échelle plus grande l'organe de blocage avec la came qui y est creusée; et
• Figs. 8 et 9 montrent à une échelle plus grande des sections partielles de la couronne à denture interne et de l'organe de blocage qui l'engage.

The characteristics and advantages of the subject of the invention will emerge more clearly from the following description of an embodiment indicated by way of nonlimiting example with reference to the appended drawings, in which:

• Fig. 1 shows a reel according to the invention seen in side elevation, on a reduced scale and with part of the envelope removed;
• Fig. 2 shows, seen from the side opposite to that of FIG. 1, the locking device connected to the winding drum, in a basic operating condition;
• Fig. 3 shows in a manner similar to FIG. 2 the device for blocking in another fundamental operating condition;
• Figs. 4 and 5 are partial views which show intermediate positions during the passage of the blocking device from the condition of FIG. 2 to the condition of FIG. 3;
• Fig. 6 shows a condition for stopping the locking device;
• Fig. 7 shows on a larger scale the blocking member with the cam which is hollowed out there; and
• Figs. 8 and 9 show on a larger scale partial sections of the crown with internal toothing and of the locking member which engages it.

The reel shown in Figure 1 comprises a support bracket 1, generally intended to be fixed to a wall or other support, which carries by means of orientation pivots 2 a casing 3 provided with a flow mouth 4. In the inside of the envelope 3 is mounted, rotatably, a winding drum 6 which is under the action of a return spring 5. In the drum 6 is wound a flexible member, such as a cable, a pipe or the like, the free end 7 of which emerges from the envelope through the flow mouth 4. The flexible member 7 can be extracted by pulling it along arrow E, thus the unwinding of the drum 6, which rotates d 'a corresponding way and loads the return spring 5. This seeks to rotate the winding drum 6 in the opposite direction, and therefore to recall the flexible member 7 in the opposite direction to arrow E. On the casing 3 is mounted a control selector 8 which can be turned relative to a fixed mark 9 to achieve, as will be described below, the different behaviors which are made possible by the reel according to the invention. These latter parts are represented by broken lines because in reality they are located on the side of the reel which is opposite to that shown in FIG. 1.

In the casing 3, to the winding drum 6 is connected a crown 10 with internal toothing, which, seen from the side of the reel opposite to that seen in FIG. 1, is shown in FIG. 2. In in particular, the crown 10 with internal toothing can be produced in one piece with one side of the take-up drum 6. The crown 10 has along its entire periphery an internal toothing 11, but along an arc of inactivity, indicates in FIG. 2 by AB, the toothing 11 does not extend, as in the other parts of the crown 10, over the entire thickness which is intended for it, but only over part of this thickness, while the remaining part of this thickness is occupied by a region 12 not toothed (see also Figure 9).

At the casing 3 is pivoted at 13 one end of an oscillating lever 14 which, at the opposite end, carries a pivot 15. The lever 14 is indicated by dotted and dashed lines assuming that it has been removed for allow observation of the underlying parts. The lever 14 is under the action of a spring, represented in the drawing only by the arrow M which shows the direction of action, and which tends to push the pivot 15 carried by the lever 14 towards the teeth 11 of the crown 10.

Inside the teeth 11 of the crown 10 is disposed an oval-shaped blocking member, shown isolated in FIG. 7. The parts of smaller curvature of the blocking member 16 have a radius substantially corresponding to the internal radius. of the toothing 11 of the crown 10. The oval locking member 16 has, on one of its end portions of greater curvature, an external toothing 17 capable of engaging with the internal toothing 11 of the crown 10, and this toothing 17 extends over the entire thickness of the blocking member 16 (see FIG. 8) and is extended by a part 18 along a short section of the part of smaller curvature of the oval blocking member . On its part of greater curvature opposite to that which we have now considered, the locking member 16 has an external toothing 19 which extends only over part of its thickness, and more precisely over the part which corresponds to the thickness part of the crown 10 on which the internal toothing 11 is continuous (see FIG. 9). In addition, the locking member 16 has, hollowed out in one of its faces, a cam in which engages the pivot 15 of the lever 14. This cam has, on each side of the center 0 of the locking member 16, a substantially radial 20 or 20 ', which extends as far as close to the periphery of the blocking member, an arcuate part 21 or 21' which follows the periphery of the blocking member, and a connecting part 22 or 22 'forming an angle, which connects the end of the arcuate part 21 or 21 'with a region of the radial part 20 or 20', close to the center 0. In FIGS. 2 to 6, the locking member 16 is shown in its all, but only its parts which are active in the condition each time considered are provided with reference figures.

Because the pivot 15 of the lever 14, loaded by the spring M, is engaged in the cam 20-22, 20'-22 'hollowed out in the blocking member 16, the latter is permanently retained in contact with the teeth internal 11 of the crown 10.

We must now consider the condition shown in Figure 2. The locking member 16 engages the toothing 11 by means of its teeth 18, and the pivot 15 is located at the end of the arcuate part 21 'of the cam, opposite to the 'end of the radial part 20'; it therefore prevents either the locking member 16 than the crown 10 (and therefore the winding drum 6) from rotating in the opposite direction to the arrow E. A rewinding is therefore not possible: the condition shown is a blocking condition.

The extraction of the flexible member 7, on the contrary, is possible, because the pivot 15 is not opposed to a movement of the locking member 16 along the arrow E; during such extraction, the pivot 15 slides along the arcuate part 21 'of the cam, until it reaches its opposite end, which is also the end of the part 20' of the cam. When this position (FIG. 4) has been reached, the toothing 19 of the locking member 16 becomes engaged with the toothing 11 and it forces the locking member to rotate around its end carrying the toothing 19, after which the pivot 15 slides along the parts 20 ′ and 20 of the cam (FIG. 5) and, pushed by the spring M, it falls into the angular part 22 of the cam (FIG. 5) thus preventing any further displacement of the locking member 16. But the latter, by effect of its displacement, has reversed its position, so that its teeth 18 no longer engage with the toothing 11, and the crown 10 can continue its rotation along the arrow E. The extraction of the flexible member 7 can be continued without obstacles.

When the traction exerted on the flexible member 7 is released, the spring 5 controls a short rewinding and the crown 10 travels a short arc in the direction opposite to the arrow E, dragging the locking member 16 with itself. Consequently, the pivot 15 leaves the angular part 22 of the cam and it falls into the end of the arcuate part 21 (FIG. 3), thus preventing the subsequent displacement of the locking member 16. The displacement of the crown 10, on the contrary, is not prevented, because the blocking member 16, having reversed its position, does not engage the teeth 11; rewinding can therefore now continue continuously. This corresponds to the position in Figure 3, which is a condition for releasing the blockage. The rewinding continues until the flexible member 7 is completely recalled, if no traction action is exerted on it from the outside, or until the rewinding is interrupted by carrying out a new extraction of the flexible member 7.

During the successive extraction of the flexible member 7, either that this extraction has interrupted the rewinding or that it is verified after a total recall of the flexible member, the phenomena indicated are repeated in an identical manner, considering the parts 20, 21, 22 of the cam exchanged between them with respect to the parts 20 ', 21', 22 ', and the teeth 17,18 with respect to the teeth 19, and therefore the blocking member 16 reverses its position again and it returns to the blocking condition of FIG. 2. Therefore, each time an extraction of the member flexible 7 is carried out, and provided that this extraction continues at least over a length which corresponds approximately to half of the perimeter of the locking member 16, this locking member reverses its position and the reel passes, d 'in an alternating manner, on the condition of blocking or on the condition of releasing the blocking.

The reversal of the position of the locking member 16 does not take place, and on the contrary it returns to the previous position by the effect of a partial rewinding carried out by the spring 5, if the extraction applied to the flexible member 7 is not sufficient to cause the pivot 15 to fall into one of the angular parts 22 or 22 ′ of the cam. That is to say that it is necessary for the extraction to be mounted at least approximately at the half of the perimeter of the blocking member 16. If at this perimeter we give a sufficiently large length we can safely avoid that the rewinding is involuntarily caused by actions exercised by accident, which generally have a reduced extension.

However, in order for the blocking condition to be reached, it is necessary for the teeth 18 to engage the teeth 11 of the crown 10. This engagement cannot take place in correspondence with the arc of inactivity AB of the teeth 11, because in this region the part 12 of the thickness of the crown 10, which is not toothed, cannot receive the engagement of the teeth 17 or 18 of the blocking member. If the arc of inactivity AB gives an appropriate length (corresponding roughly to half of the perimeter of the locking member 16), and it is placed in an adequate position relative to the point where the flexible member 7 is anchored to the winding drum 6, it is possible to prevent the blocking being activated when the length of flexible member still contained in the reel is so small that it would not allow sufficient extraction to cause the blocking member to overturn 16. In this way there is no danger that the rewinding can no longer be activated after an extraction total of the flexible member 7.

In the particularly improved embodiment which is shown, a stop 23 is also provided, supported by a lever 24 connected to the control selector 8. The stop 23 can be moved, by actuating the selector 8, between an inactive position, shown in solid lines in Figures 2 to 5, and an activity condition, shown in dotted and dashed lines in Figures 2 to 5 and solid lines in Figure 6.

Until the stop 23 is in its inactive position, it does not interfere with the movements of the locking member 16, and the latter behaves as described. When, on the contrary, the stop 23 is moved to its activity position according to FIG. 6, it stops the blocking member 16 at the start of its movement and it does not allow it to reach the positions according to FIGS. 4 and 5, and therefore to reverse its own position.

FIG. 6 shows only the case in which the stop 23 prevents the passage of the blocking member 16 from the blocking condition to the condition of releasing the blocking, but it is quite clear that the behavior of the stop 23 is identical to prevent the passage of the blocking member 16 from the release condition of the blockage to the blocking condition.

If, when the stop 23 is activated, the blocking member was in the blocking condition according to FIG. 2, it follows that the flexible member 7 can be freely extracted, on one or more occasions , but that no rewinding can take place except over a short portion. The reel behaves like a free wheel which allows the extraction but not the rewinding of the flexible member 7. This condition continues until, by operating in the opposite direction the control selector 8, the stop 23 is again moved to its inactive position, after which the reversal of the position of the blocking member 16, and therefore the release of the blocking, is authorized again.

If, on the contrary, during the activation of the stop 23 the blocking member 16 was in the condition of release of the blocking according to FIG. 3, it follows that the flexible member can be freely extracted, in one or more times, but the rewinding takes place each time the traction exerted on the flexible member 7 is released. The reel behaves like a reel provided with a return spring but not with a locking member. This condition continues until, by actuating the control selector 8 in the opposite direction, the stop 23 is again moved to its inactive position, after which the reversal of the position of the locking member 16 , and therefore the new activation of the blocking, is authorized again.

In this way the reel provided with the blocking device according to the invention can be instantly adapted either to different application requirements, or also to specific conditions of use which may arise temporarily in each application.

It is obvious, however, that in the embodiments for which this possibility of modifying the behavior of the reel is not of interest, the selection device 8, 9, 23, 24 can be omitted.

Of course, the dimensions and the proportions of the reel and, consequently, of its blocking device, can be considerably modified according to the nature, the dimensions and the length of the flexible member 7 wound. Also the conformation of the envelope 3 and, in general, of the structure of the reel, can be modified without introducing substantial modifications in the blocking device. The cam hollowed out in the blocking member 16 has been shown to be symmetrical with respect to the center 0, but for practical reasons it could receive an asymmetrical shape. Also other modifications are possible within the scope of the claims.

Claims (4)

1. A reel comprising a winding drum (6) rotatably mounted in a supporting structure (3), a return spring (5) for the winding drum (6) and a controllable device for locking the winding drum (6), the lock device including a crown (10) with internal toothing (11), connected to the winding drum (6), characterized in that said toothing (11) extends on the whole thickness of the crown (10) along the most part of this latter, but it is limited to a part of this thickness along a pre-established inactivity arc (A-B); and that said controllable lock device further comprises a lock member (16) of oval shape, provided with external toothings (17-18,19) on its end portions having a larger curvature, the first (17-18) of these toothings extending on one side on a part (18) of the portion of the lock member (16) having a smaller curvature, and the second toothing (19) being limited to a part of the thickness of the lock member (16), corresponding to the part of thickness on which extends the toothing (11) of said crown (10) with internal toothing along said inactivity arc; said lock member (16) being mounted inside the toothing (11) of the crown (10) and having, hollowed in one of its faces, a profiled cam (20-22,20'-22') comprising, on each side of the lock member (16) with respect to the centre (0) thereof, a first portion (20,20') radially extending up to a position near the outline of the lock member (16), a second portion (21,21') extending along a part of the outline of the lock member (16), and a third intermediate, angular portion (22, 22') connecting said first and second portions of the cam (20-22,20'-22'); a pivot (15) engaged in said cam (20-22, 20'-22'), mounted on the supporting structure in such a way as to be radially displaceable with respect to the crown (10); and a spring (M) arranged for pushing said pivot (15) towards the periphery of the crown (10).
2. A reel as set forth in Claim 1, characterized in that said pivot (15) is mounted at the end of a first lever (14) whose opposite end is pivoted on the fixed reel structure (3), and that said spring (M) is arranged for pushing said first lever (14) and said pivot (15) towards the internal toothing (11) of said crown (10).
3. A reel as set forth in Claim 1, characterized in that the lock device also includes a stop member (23) which may be displaced, by action of a control selector (8), between a position in which it does not interfere with the displacement of the lock member (16) and a position in which it stops the lock member (16) during its displacement, thus preventing the overturning of its position.
4. A reel as set forth in Claim 3, characterized in that said stop member (23) is mounted on one end of a second lever (24) which may be displaced by means of the control selector (8) mounted on the supporting structure (3) of the reel.

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