Abstract:
The device comprises a male assembly, in the form of a cylindrical part, engaged such that it is free to slide inside a female assembly, in the form of a sleeve with a central bore for receiving the male assembly, that defines an opening for engaging and an opening for disengaging of said male assembly, the said male and female assemblies include supplementary arrangements, which, in connected position, are able to abut against each other to stop the sliding of the male assembly in the direction of disengagement, where, in disconnected position, the said arrangements can release themselves from each other under the effect of axial tensile force greater than the predetermined threshold value, relatively applied on the male assembly in the direction of disengagement in order to separate one from the other of the said male and female assemblies.

Description:
BACKGROUND 
       [0001]    Technical Field 
         [0002]    This invention relates to a safety connection device that opens automatically when a tensile force greater than a threshold value is applied to it. 
         [0003]    Description of the Related Art 
         [0004]    As an advantage, the threshold tensile force that can trigger the opening of the device is adjustable. Moreover, according to the invention, the device is reusable and can be reconnected. 
         [0005]    This device can, for example, be used while practicing horseback riding or when taking care of horses or other animals, which must be attached to a fixed point. 
         [0006]    In fact, when a horse is attached to a fixed point, especially by using a lanyard or a rope attached to a ring fixed in the wall, it sometimes “pulls backwards.” This situation usually occurs when the horse is frightened for some reason and begins to panic. It then brutally throws itself back and pulls on the clip with all its strength to cut loose. 
         [0007]    In this state of panic, the horse can get seriously injured and up to the point where it can rupture its cervical if we do not release it at once. Now, while pulling backwards, the horse tightens the knots that hold it to the ring, making any attempt at release impossible. The only solution then is to cut the rope as quickly as possible. 
         [0008]    However, if such a situation occurs when there is no one around or it happens in front of people who do not have knives or who cannot cut the rope fast enough since it is generally very strong and difficult to cut, the consequences can be serious. 
         [0009]    To solve this problem, different solutions have been proposed in the prior art. 
         [0010]    For example there are elastic devices, called elastic lanyards, that are interposed between the halter of the horse and the ring attached to the wall, and which increases in length as the horse pulls back. 
         [0011]    However, using such elastic ropes can be very dangerous to the animal. In fact, in some cases it happens that the horse, after being abruptly pulled back, finds itself propelled forward through elastic reaction and hits the wall violently with its head. Such shock can cause irreversible damage to the animal, sometimes even kill it. 
         [0012]    Connecting devices have also been proposed in the prior art, which break automatically when the pull of the horse is greater than the breaking strength value. This can, for example, be a simple weaker cord, interposed between the lanyard of the horse and the ring fixed in the wall, as also more sophisticated anti-panic devices. 
         [0013]    While such devices solve the technical problem by automatically releasing the horse to prevent it from hurting itself, they nevertheless have a number of disadvantages. 
         [0014]    These devices typically operate by the breaking of an element having the weakest resistance. They are therefore destroyed on use and cannot be put back in place and reused thereafter. 
         [0015]    Furthermore, the strength required for safety opening of the device is only approximately known and cannot be changed. It cannot be adjusted to suit the situation, especially the strength, age or weight of the horse. 
         [0016]    Finally, these devices are mostly made of metal and can hurt the animal, because after the device breaks, the piece connected to the lanyard of the animal may strike it violently due to panicked, abrupt and disorderly movements of the animal. 
         [0017]    For all these reasons it would be desirable to have a safety connector that is efficient, reusable, adjustable and safe for the animal. 
         [0018]    This is the objective that the invention proposes to achieve. 
       BRIEF SUMMARY 
       [0019]    In order to solve this technical problem, the invention offers a safety connection device with automatic release under the effect of an axial tensile force exerted on it, which is greater than a predetermined threshold value. 
         [0020]    According to the invention, the safety connection device is notable in that it comprises a male assembly that is freely engaged by being slid inside a female assembly. The male and female assemblies include supplementary arrangements, which, in connected position, are able to abut against each other to stop the sliding of the male assembly in the direction of disengagement, where, in disconnected position, the said arrangements can release themselves from each other under the effect of axial tensile force greater than the predetermined threshold value, relatively applied on the male assembly in the direction of disengagement in order to separate one from the other of the said male and female assemblies. 
         [0021]    While, according to the invention, the device is particularly suitable for being used in the field of horseback riding and horse breeding, its use is in no way limited to such an application. 
         [0022]    The device, according to the invention, can be used for all applications requiring an axial tension limiter and for which a safety disconnection is desired when a threshold tensile value is reached. 
         [0023]    As an advantage, each one of the male and female assemblies include means for hooking an element; at least one of the elements is capable of exerting the axial tensile force in the direction opposite to the other element. 
         [0024]    In this way, the device according to the invention may equally be connected on the one hand to a fixed point and on the other to a movable element (object, animal or person) capable of exerting a tensile force; or to two mobile elements each exerting, or being able to exert, a tensile force in a generally opposite direction. 
         [0025]    Some possible examples of possible uses of the device according to the invention are being mentioned (list not exhaustive): 
         [0026]    When a load has to be lifted or pulled by a man, an animal or by using a handling equipment (crane, hoist, trolley, etc.), and for safety or other reasons it is necessary to prevent the lifting or pulling of too much weight, in order, for example, to avoid injuries to humans or animals or to prevent damaging the handling equipment; when an animal is attached to a fixed point and is likely to injure itself by pulling hard on its tie; 
         [0027]    when a person, an animal or a device is connected to a mobile load or part, and it is required to detach him/it from this mobile load or parts if the sustained stress exceeds the safety threshold;
       when two machines or animals pull in opposite directions on the same device that needs to be preserved.       
 
         [0029]    In general, the device according to the invention may advantageously be used in any situation where it is desirable to automatically disconnect two previously connected assembles, when the tensile force being exerted on them reaches a threshold limit. 
         [0030]    This will thus ensure human or animal safety and/or preserve the integrity of goods, when they may be subject to excessive tensile force. 
         [0031]    Preferably, the safety connection device comprises means for adjusting the engagement of one of the supplementary arrangement on the other during the abutment, so as to adjust the predetermined threshold value of the axial tensile force required for separating the male and female assemblies. 
         [0032]    According to a specific embodiment of the invention, one of the supplementary arrangements is formed by a shoulder extending perpendicularly to the direction of disengagement, and capable of abutting against the other supplementary arrangement in the position of engagement. 
         [0033]    According to a specific embodiment, one of the supplementary arrangements is retractable in relation to the other under the effect of axial tensile force greater than the predetermined threshold value. 
         [0034]    Furthermore, the shoulder intended to abut against a supplementary arrangement, advantageously has an inclined surface to facilitate release of the abutment under the effect of axial tensile force greater than the predetermined threshold value. 
         [0035]    According to a specific embodiment of the invention, one of the supplementary arrangements is retractable in relation to the other under the effect of axial tensile force greater than the predetermined threshold value. 
         [0036]    In fact, one of the supplementary arrangement may, for example be in the form of at least one retractable ball screw, arranged in a transverse threaded bore. The retractable ball is capable of abutting against the other supplementary arrangement in the position of connection. 
         [0037]    As an advantage, the device comprises a plurality of retractable ball screws, arranged in multiple transverse threaded bores, and habitually distributed around a longitudinal axis corresponding to said direction of disengagement. 
         [0038]    According to specific embodiments, the female assembly is, e.g., in the form of a sleeve having a central bore for receiving the male assembly, and defining one opening of engagement and one opening of disengagement of said male assembly. The male assembly is in the form of a cylindrical part adapted to slide within the female assembly. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0039]    Other characteristics and advantages of the invention will appear on reading the detailed description which follows, such description made with reference to the accompanying drawings wherein: 
           [0040]      FIG. 1  is a perspective view of an example of connection device according to the invention; 
           [0041]      FIG. 2  is a top view of the  FIG. 1  connection device; 
           [0042]      FIG. 3  is a longitudinal section view, along the section plane of  FIG. 2  of the  FIG. 1  connection device; 
           [0043]      FIGS. 4 to 12  are schematic perspective views explaining the functioning of the connection device, with:
       a first sequence, shown in  FIGS. 4 and 5 , which illustrates the safety disconnection of the connection device, and   a second sequence, shown in  FIGS. 6 to 12 , which illustrates the successive steps for reconnecting the connection device for its reuse;       
 
           [0046]      FIG. 13  is a cutaway perspective view of the  FIG. 1  connection device illustrating the adjustment of threshold value of the allowed tensile force; 
           [0047]      FIG. 14  is an enlargement of a detail of  FIG. 13 . 
       
    
    
     DETAILED DESCRIPTION 
       [0048]    The safety connection device according to the present invention will now be described in detail with reference to  FIGS. 1 to 14 . Equivalent elements shown in different Figures will bear the same numeric references. 
         [0049]    The remainder of this description will define the terms top and bottom, upper and lower, etc., depending on the orientation adopted by the connection device shown in  FIG. 1 . It is obvious that this orientation will not necessarily be maintained while in use. 
         [0050]    In the various figures, a preferred example is shown of a connection device  1  according to the invention. 
         [0051]    This connection device  1  comprises two main assemblies: a male assembly  2  and a female assembly  3 , with one engaged inside the other in position of connection and capable of separating from one another in position of disconnection. More specifically, the male assembly  2  is engaged such that it is free to slide inside the female assembly  3 . 
         [0052]    The female assembly  3  comprises a sleeve  4 , preferably cylindrical, having a central bore  5 , opening out on the upper part of the sleeve  4  and extending in its axial direction. This central bore  5  is intended to receive inside it the male assembly  2 , which is coaxially engaged in the position of connection of the device  1 . The central bore  5  therefore has a diameter adapted to the dimensions of the male assembly  2 . 
         [0053]    Preferably, the central bore  5  extends, after a shoulder  6 , through a coaxial bore  7  of larger diameter opening out on the lower part of the sleeve  4  and thereby forming, downwards, an opening of engagement  8  of said male assembly  2 . In contrast to the opening of engagement  8 , the bore  5  opens out toward an opening of disengagement. 
         [0054]    This opening of engagement  8  is intended to house the upper end  9  of an anchor  10 , such as for example a clasp  11  in the shown embodiment, or a ring, a hook or any other similar device for attaching the female assembly  3  of the connection device  1  and thus connecting it to a fixed point or to an element capable of exerting or undergoing a tensile force. 
         [0055]    The upper end  9  of the anchor  10  is held in a removable manner in the opening of engagement by means of a temporary holding mechanism, preferably a dowel  12  traversing through it, or by any other temporary attachment mechanism that can be devised by the expert. 
         [0056]    The sleeve  4 , for this purpose, comprises a cross bore  13  located at the level of the opening of engagement  8 , which extends radially and opens out on both sides of the sleeve after passing through this opening of engagement  8 . 
         [0057]    This cross bore  13  allows engagement of the dowel  12  through the sleeve  4 , via the opening of engagement  8  and thus through the upper end  9  of the anchor  10  which ensures that it is held in place. 
         [0058]    The dowel  12  is removable and is held temporarily in the cross bore  13 . The dowel  12  can be held in position, for example, by using a peripheral ring  14  having diameter greater than that of the cross bore  13 , serving as an abutment for one end of the dowel  12  and by means of a pin  15  which is engaged in a removable manner to the other end of the dowel  12 . 
         [0059]    The sleeve  4  further comprises at least one, and preferably multiple threaded bores  16 , arranged radially in a plane transverse to the sleeve  4  and traversing the outside of the sleeve  4  into its central bore  5 . These threaded bores  16 , substantially horizontal, are preferably uniformly distributed over the periphery of the sleeve  4 . The preferred embodiment shown in the Figures comprises eight of them. 
         [0060]    In each of these threaded bores  16  one screw  17  is engaged by tightening at the retractable end, for example round-headed screw but preferably ball screw  18 . The other end of these screws is adapted to be operated from the outside by a common screwing tool. For example it can be slotted or Phillips type so that it can be used with a flat  19   FIGS. 13 and 14 ) or cross screwdriver respectively, or even the hexagon slotted type that can be worked with an Allen key. 
         [0061]    The male assembly  2  of the connection device  1  according to the invention is made of one shaft  20  in two successive sections: a first section or lower section  21 , substantially cylindrical and with a diameter substantially corresponding to that of the central bore  5  of the sleeve  4 , while being slightly less than it so that it can be engaged with it, extended axially by a second section or upper section  22  of smaller diameter. 
         [0062]    The lower section  21  of the shaft  20  and the upper section  22  having a smaller diameter are gradually connected, at a level of a chamfered area forming a shoulder  23  with inclined surface and can be used as a ramp. This shoulder  23  can, for example, be made as represented by using a washer  24 . 
         [0063]    In order to compensate for manufacturing tolerances and ensure suitable support of the lower section  21  of the male assembly  2  in the central bore  5  of the sleeve  4  in connection position of the device, the lower section  21  of the male assembly  2  may further comprise a circular groove  25  in which an O-ring  26  is preferably inserted. 
         [0064]    The male assembly  2  lastly comprises, in the upper section  22  of the shaft  20 , a receiving area  27  for a second anchor  28  for anchoring the male assembly  2  of the connection device  1  according to the invention and thus connecting it to a fixed point or to another element capable of exerting or undergoing a tensile force. 
         [0065]    Although many other variants can be devised by those skilled in the art, the receiving area  27  on the embodiment shown consists of a single transverse through bore  29  wherein it is possible to insert, for example, a ring  30 , a hook, a clasp, or directly a rope, strap, lash, tether, chain, lanyard, or the end of a harness or other appropriate anchor. 
         [0066]    This receiving area  27  is made at the free end of the second section  22  of the shaft  20  which always stays accessible regardless of the position of the connection device  1  according to the invention, even when the male assembly  2  is engaged in the female assembly  3  of the device in position of connection. 
         [0067]    According to another conceivable alternative, the receiving area  27  can directly act as an anchor  28  and be, for example, in the form of a loop projecting from the upper section of the shaft  20 . 
         [0068]    In connection position of the device  1  according to the invention shown in  FIGS. 1 to 4 , the male assembly  2  of the device is engaged in the female assembly  3 . For this purpose, the shaft  20  of the male assembly  2  is inserted in the central bore  5  of the sleeve  4  so that the upper section  22  having smaller diameter of the shaft  20  comes opposite the threaded bores  16  of the sleeve  4  and the free end of this upper section  22  protrudes out of the sleeve  4  above it. 
         [0069]    Ball screws  17  are engaged in threaded bores  16  of the sleeve  4  and are sufficiently recessed so that their retractable end, preferably their ball  18 , protrudes into the central bore  5  of the sleeve  4  and they narrow its diameter at this level, thus making it lesser than that of the lower section  21  of the shaft  20 , however being greater than or equal to that of the upper section  22  of the shaft  20 . 
         [0070]    Ball screws  17  thus hold the device according to the invention in position of connection when no force is exerted on it or when it is subjected to a tensile force intended to separate the two assemblies  2 ,  3  of the connection device  1  which is moderate, i.e., less than a threshold value. In fact, in this case, the retractable ends  18  of the ball screws  17  abut against the inclined shoulder  23  of the shaft  20  and obstruct the shaft  20  from coming out of the sleeve  4 . 
         [0071]    The operation of the connection device  1  according to the invention ensues evidently from the means described above. For a clearer understanding of the reader, it has been schematically shown in an example of use in  FIGS. 4 and 12  and will be briefly described below. 
         [0072]    The connection device  1  according to the invention was shown in  FIG. 4  in position of connection. It is connected on one side by the clasp  11  of its female assembly  3  to a ring  31  fixed to a wall  32  thereby forming a fixed point. On the other side, it is connected by means of a ring  30  inserted in the through bore  29  of its male assembly  2  to a rope  33  connected to the harness  34  of a horse  35  capable of exerting a tensile force backwards to release itself. 
         [0073]    As explained above, so long as the horse  35  does not pull on the rope  33  or does not exert a high tensile force, the ball screws  17  hold the device  1  in the connection position ( FIG. 4 ). 
         [0074]    When the horse  35  begins to pull very hard on the rope  33 , for example if it starts “pulling backwards,” it pulls on the male assembly  2  which moves in the central bore  5  toward the disengagement opening of the sleeve  4 . Balls  18  of the ball screws  17  come against the inclined shoulder  23 . 
         [0075]    If the tensile force is greater than a threshold value, which corresponds to the force required to counter the elastic strength of the springs contained within the ball screw  17  and thus push the retractable balls  18  inside the body of these ball screws  17 , the balls  18  retract gradually and free up the path in the central bore  5 . The lower section  21  with largest diameter of the shaft  20  can then slide into the central bore  5  to come out of the sleeve  4  through the opening of disengagement. The device  1  according to the invention is now in disconnected position, its male assembly  2  and its the female assembly  3  are separated from one another as illustrated in  FIG. 5 . The horse  35  is thus released and runs no risk of getting injured. 
         [0076]    The retraction of the balls  18  from the ball screws  17  is facilitated by the inclined nature of the shoulder  23  which forms a gradual support ramp on them. The resistance to disconnection resisted by the device  1  according to the invention may thus be more or less pronounced depending on the angle of inclination selected for the shoulder  23 . 
         [0077]    As an advantage, the connection device  1  according to the invention is reusable and can be very simply put back in position of connection. 
         [0078]    To do this, simply remove the pin  15  ( FIG. 6 ), then the dowel  12  ( FIG. 7 ) of the female assembly  3 . 
         [0079]    The clasp  11  can then be removed out of the opening of engagement  8  of the sleeve  4  ( FIG. 8 ). The male assembly  2  can then be placed in the female assembly  3  through the opening of engagement  8  that has a diameter greater than that of the central bore  5 . 
         [0080]    Once the male assembly  2  is correctly positioned in the female assembly  3 , i.e., when the inclined shoulder  23  of the shaft  20  abuts against the balls  18  of the ball screws  17  which are automatically returned to the projecting position under spring action, simply put back the top end  9  of the clasp  11  in the engagement opening  8  of the sleeve  4  ( FIG. 9 ), then block this clasp  11  using the dowel  12  ( FIG. 10 ) and the pin  15  ( FIG. 11 ). 
         [0081]    The connection device  1  according to the invention is once again in connected position, ready to be reused ( FIG. 12 ). 
         [0082]    According to a particularly advantageous aspect of the invention, the connection device  1  can be adjusted as illustrated in  FIGS. 13 and 14 . 
         [0083]    In fact, by pressing the ball screws  17  more or less in the threaded bores  16  of the sleeve  4 , it is possible to adjust the pressure exerted by the balls  18  (or rods) of the ball screws  17  on the inclined shoulder  23  of the shaft  20  and thereby the threshold value of the traction force necessary to disconnect the device  1 . 
         [0084]    If it is desired, for example, that the device  1  disconnects less easily, i.e., the threshold value of the tensile force be increased, it is sufficient to press the ball screws  17  deeper in the threaded bores  16  and vice versa if the situation is reversed. 
         [0085]    This adjustment can be made very easily, with a simple screwdriver or Allen wrench). 
         [0086]    The connection device  1  according to the invention is remarkable for its simplicity of implementation. It is made exclusively of mechanical components, whose functioning is completely reliable and is independent of any external operating member. Many applications can be envisaged, which include, for example but not limited to, safety of humans and animals, protection of goods, etc. 
         [0087]    Where the connection device is desired to be used for a human or an animal, it is preferable to use a lightweight material such as, for example, a resistant plastic material, specifically polyoxymethylene, to make the device. This will ensure safety of the person or the animal in question in case of impact with a section of the device during its disconnection. Using such plastic material also allows outdoor use of the connection device  1  according to the invention. 
         [0088]    The invention is naturally not limited to the preferred embodiments described above and shown in various figures; the expert can make numerous changes to it and imagine other variants without departing either from the scope or from the framework of the invention defined by the claims. 
         [0089]    The various embodiments described above can be combined to provide further embodiments. Aspects of the embodiments can be modified, if necessary to employ concepts of the various patents, applications and publications to provide yet further embodiments. 
         [0090]    These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.