Patent Application
20240207684
The invention relates to a camming clamping device, to a method for manufacturing a camming clamping device and to a method for replacing a wire element of a camming clamping device.
During the climbing phases, a climber is required to place protection points in a rockface. The climber successively installs several protection points that are designed to support him in case of a fall. Certain rockfaces are equipped with pre-installed protection points, for example in the form of spits that are sealed in the rock. Other rockfaces are not equipped with such points so that the climber has to find the crevice that is most suitable for installing his protection point.
When the climber has to place his/her protection points, it is conventional practice to install passive chocks and active chocks. The chocks are designed to be inserted in crevices that are generally holes, cracks, channels or any other recess that is deep enough for a chock to be inserted. Each particular shape of crevice is suitable for a particular chock configuration. In conventional manner, for chocks, the head is arranged at a first end and is designed to wedge. The opposite end defines a through hole designed to receive a carabiner. The through hole is generally delineated by a steel cable. The steel cable is sunk at one or more places in the head and/or it is crimped to define the ring designed to receive the carabiner.
Passive chocks are often formed by metal parts having a specific shape. In passive chocks, the volume is constant or substantially constant throughout its use. In a first spatial position, the chock can be inserted in a fault of a rockface and, in a second spatial position, the chock is wedged between two opposite faces of the fault. It is then possible to install and remove the chock easily or to wedge the chock, provided that the latter is placed in the right spatial configuration inside the hole. For certain types of passive chocks, the steel cable is replaced by a strap made from textile material. The strap forms a ring that is closed by a seam after the strap has passed through the head several times.
The different configurations currently marketed do not provide for replacement of the material or materials forming the ring with respect to the head. Consequently, if the ring is damaged or worn, the whole of the chock has to be replaced.
Historically, it is known to form a ring that is constituted by a strap or a rope that passes through the head sub-assembly and is closed by means of a knot. Closing of the ring by one or more knots gives rise to problems of repeatability and resistance over time, in particular when materials with a low friction coefficient are used, which does not enable the knots to be sustained over time.
In active chocks, one or more cams are stressed to modify the size of the head of the chock. For active chocks, it is also known to wedge one end of a steel cable in a part of the head in irremovable manner. The other end of the cable is shaped to form a loop that is closed by crimping.
Active chocks are also known that use a mechanical connection between the head and the annular end by means of a textile wire element defining a loop by joining the two ends of the wire element by a splicing step. The parts of the rod are passed through by the wire element before the wire element loop is formed. The loop is then fixed to the head of the chock. Such a configuration makes it difficult to secure the textile wire element with the head as the available space is limited and the axes of rotation of the cams are substantially at the same height as the insert so that the insert is located between the cams in the extended position. Furthermore, the rod being formed and the wire element being subjected to a tensile stress, the fixing between the head and the wire element makes the operation complicated.
Such a configuration makes it very difficult or even impossible to replace the wire element if the latter is damaged or at end of life. As the wire element is made from textile material, it ages much more quickly than the head assembly. The lifetime of the chock is then defined by the lifetime of the wire element.
One object of the invention consists in providing a camming clamping device with a mechanical connection between the head and the annular end that is more easily replaceable than the configurations of the prior art.
According to one feature of the invention, the camming clamping device comprises:
The camming clamping device is remarkable in that the at least one loop is passed through by a tube and in that the tube and the at least one loop are passed through by an anchorage fixed to the head to constitute the mechanical continuity between the head and the attachment point.
In advantageous manner, the anchorage is removable with respect to the head or destructible independently from the head to allow the head sub-assembly and rod sub-assembly to be separated.
In a particular configuration, the wire element is subjected to a tensile stress in a longitudinal direction of the rod and of the wire element, the rod forming a stop opposing movement of the tube towards the through hole.
In an advantageous development, the wire element has several loops, the loops being passed through by the tube and the anchorage.
Preferentially, the tube is divisible and installed fixedly in the head. Extraction of the tube from the head causes destruction of the tube.
According to one embodiment, the anchorage is a screw. At least one of the head and the tube has a thread receiving a thread of the screw to secure the anchorage with the head.
In an advantageous development, the anchorage is an insert crimped with the head.
Preferentially, the anchorage is a rod fixed to the head by means of an irremovable clip.
In another advantageous development, the wire element is a ring made from textile material.
Preferentially, the wire element is a ring folded to define at least two legs each comprising a top end, a bottom end and two strands,
In advantageous manner, the at least one cam is installed movable swivelling with respect to a body of the head between an extended position and a retracted position, the anchorage being fixed to the body, and a spring is fixed on the one hand to the body and on the other hand to the cam to be able to bias the cam away from the extended position
It is a further object of the invention to provide a method for manufacturing a camming clamping device that is easier to perform than the methods of the prior art.
This result tends to be achieved by means of a method for manufacturing comprising the following steps:
It is a further object of the invention to provide a method for replacing a wire element of a camming clamping device that is easier to perform than in the configurations of the prior art.
This result tends to be achieved by means of a method for replacing comprising the following steps:
Other advantages and features will become more clearly apparent from the following description of particular embodiments and implementation modes of the invention given for non-restrictive example purposes only and represented in the appended drawings, in which:
The camming clamping device comprises a head sub-assembly 1 and a rod sub-assembly 2. The head sub-assembly 1 is located at a first end and comprises a head 3 and at least one cam 4. The head sub-assembly 1 is designed to wedge in a crevice.
The rod sub-assembly 2 has a rod 5, a wire element 6 and a tube 7. The rod 5 is hollow and is passed through by the wire element 6. The rod sub-assembly 2 defines an annular end 2a that has a through hole 8. The wire element 6 delineates the through hole 8. In other words, the wire element 6 surrounds the through hole 8 either alone or in combination with its attachment point or points with the head 3. Once the wire element 6 has been attached to the head 3, the wire element 6 constitutes the mechanical continuity between the head 3 and the opposite end of the chock represented by the through hole 8 designed to form an attachment point, i.e. designed to receive a connector. The rod 5 extends mainly in a first direction XX that corresponds to the longitudinal direction of the rod 5, i.e. its largest dimension. The rod 5 has a top end designed to be fixed to the head 3 and a bottom end designed to define an annular end 2a defining the through hole 8. The bottom end and the top end are opposite one another in the XX direction.
The attachment between the wire element 6 and the head 3 facilitates separation of the head sub-assembly 1 and the rod sub-assembly 2 to make replacement of the wire element 6, and in more general manner of at least one of the components of the rod sub-assembly 2, easier to perform.
The wire element 6 defines at least one loop 6a and the tube 7 passes through the at least one loop 6a. The tube 7 and the at least one loop 6a are passed through by an anchorage 9 that is fixed to the head 3. The anchorage 9 constitutes the mechanical connection between the wire element 6 and the head 3. To facilitate total or partial replacement of the rod sub-assembly 2, it is important to facilitate installation of the wire element 6 in the head 3.
The tube 7 prevents the loop 6a from closing thereby facilitating installation of the anchorage 9 in the loop 6a to constitute the mechanical continuity between the head 3 and the rod sub-assembly 2. The tube 7 forces the loop 6a to define a minimum cross-section that is substantially equal to or larger than the cross-section of the anchorage 9. When the loop 6a is installed in the head 3, the loop 6a rubs against the head 3 and can deform, but it keeps an opening that is equal to or larger than the cross-section of the anchorage 9 to allow the anchorage 9 to be attached to the head 3 and to the wire element 6 through the tube 7.
In a preferential embodiment illustrated in
Advantageously, the head 3 has a body 3a defining a cavity receiving a top end of the rod 5. The tube 7 is completely hidden by the body 3a in a direction perpendicular to the direction of insertion of the top end in the cavity.
In preferential manner, the position of the tube 7 with respect to the top end of the rod 5 is stationary in the XX direction.
The head 3 defines a cavity, for example a blind cavity, that is designed to receive the rod 5, the tube 7 and the loop 6a. In order to preserve an acceptable compactness, the cavity has a reduced cross-section and preferably a cross-section that is complementary to the cross-section of the rod 5 perpendicularly to the first direction XX.
In preferential manner, the tube 7 has a width that is equal to or larger than the width of the rod 5, as illustrated in
In particularly advantageous manner, the wire element 6 is completely hidden inside the rod 5 with the exception of the loop 6a or the loops 6a that are salient on one side of the head of the rod 5. The part of the head of the rod 5 is designed to be inserted in the head 3.
In a particular embodiment, the anchorage 9 is installed removable with respect to the head 3. For example, the anchorage 9 is a screw, a bolt or any other element that can be installed on the head 3 and removed several times. Such a configuration enables the rod sub-assembly 2 and the head sub-assembly 1 to be separated easily.
In an alternative embodiment, the anchorage 9 is installed destructible independently with respect to the head 3. The anchorage 9 can be destroyed with respect to the head 3 without destroying the head 3. Such a configuration enables several rod sub-assemblies 2 to be successively installed on the same head sub-assembly 1 replacing the anchorage 9 by a new anchorage 9. Destruction of the anchorage 9 enables the rod sub-assembly 2 to be replaced and incites the user to install a kit comprising a new anchorage 9 and a new wire element 6. The anchorage 9 can be an insert that is crimped, stuck, welded, brazed or fixed by any other irremovable fixing means.
In the previous embodiments, the tube 7 is preferentially divisible and is installed fixedly in the head 3. Extraction of the tube 7 from the head 3 and/or removal of the anchorage 9 results in destruction of the tube 7.
In preferential manner, when the anchorage 9 is fixed to the head 3, the tube 7 is fixed in irremovable manner with respect to the anchorage 9. Disassembly or destruction of the anchorage 9 destroys the tube 7. This has the effect of preventing reuse of the tube 7 or of making reuse thereof more difficult. It is then possible to detect a wire element 6 that has already been used as it has already been installed. For example, the anchorage 9 has a cross-section that is slightly larger than the cross-section of the through hole 8 of the tube 7. As the anchorage 9 is progressively inserted in the tube 7, the tube 7 breaks preventing the tube 7 from being reused. As an alternative, once the anchorage 9 has been fixed to the head 3, a portion of the anchorage 9 is fixed to the tube 7. The fixing between the anchorage 9 and the tube 7 is one-way. When the anchorage 9 is sought to be removed, the tube 7 is destroyed. It is further possible to have an anchorage 9 that grinds a part of the thickness of the tube 7. Insertion of the anchorage 9 reduces the thickness of the tube 7, weakening the tube 7 that is no longer able to prevent deformation of the strap and makes a subsequent insertion of the anchorage 9 complicated.
In a particular embodiment, the wire element 6 is subjected to a tensile stress in the longitudinal direction XX of the wire element 6 between the head 3 and the through hole 8. The rod 5 acts as end-of-travel stop on the tube 7. The rod 5 prevents the tube 7 from moving towards the through hole 8 beyond a threshold position. The wire element 6 is under tension which enables the position of the strap to be fixed with respect to the tube 7. Installation of the wire element 6 under tension ensures a good resistance of the rod sub-assembly 2 over time before the latter is attached with the head sub-assembly 1. A rod 5 of adjustable length can be used to apply a tensile stress.
In a preferential embodiment, the wire element 6 has several loops 6a. Each of the loops 6a is attached to the head 3. In advantageous manner, the loops 6a are installed facing one another and are passed through by a tube 7 and one and the same anchorage 9.
In a particular embodiment, the anchorage 9 is a screw. In the configuration illustrated in
In the configuration illustrated in
In the embodiment illustrated in
In a preferred embodiment, the camming clamping device is an active clamping device as illustrated in
The head sub-assembly 1 forms a first end that is a head 3. The rod sub-assembly 2 forms the opposite end to the head end and defines an annular end 2a. The head 3 has at least one cam 4 and preferably several cams 4 that are installed movable swivelling between an extended position and a retracted position. The cam or cams 4 are installed movable around at least one pivot shaft 13 of the head 3. The cam or cams 4 are mechanically coupled to a body 3a of the head 3. The pivot shaft 13 is fixed to the body 3a of the head 3. The body 3a can be formed by one or more parts. The at least one cam 4 is installed swivelling with respect to the body 3a. The pivot shaft 13 extends mainly in a second direction YY that is perpendicular or substantially perpendicular to the first direction XX.
In conventional manner, the annular end 2a is in the form of a ring that defines a through hole 8 configured to receive a carabiner. The annular end 2a is able to support the weight of a user.
The camming clamping device has a wire element 6 that connects the head 3 mechanically with the annular end 2a. The wire element 6 extends continuously from the head 3 up to the annular end 2a in a first direction XX. The wire element 6 is attached to the head 3 at each of its ends and extends along the annular end 2a between its attachment points with the head 3. The wire element 6 constitutes the mechanical continuity between the head 3 and the annular end 2a. The wire element 6 couples the cams 4 mechanically to the annular end 2a so that a user attached to the annular end 2a is securedly held by means of the cams 4 wedged for example in a crack.
The clamping device comprises an actuating system coupled to the at least one cam 4. The actuating system is configured to selectively engage the retracted position of the at least one cam 4. The actuating system has a trigger 14 installed able to slide along the first direction XX connecting the head 3 and the annular end 2a.
In other words, the trigger 14 is installed movable with respect to the head 3 and is coupled to the at least one cam 4. When the trigger 14 is outside the first position, the at least one cam 4 is outside the extended position.
Preferentially, the trigger 14 is coupled to the at least one cam 4 so that movement of the trigger 14 away from the head 3 results in a movement of the at least one cam 4 away from the extended position, i.e. to the retracted position. In preferential manner, the trigger 14 is coupled to all the cams 4 so that movement of the trigger 14 away from the head 3 results in movement of cams 4 to the retracted position.
It is advantageous for movement of the trigger 14 in the direction of the head 3 not to impose any movement of the cam 4 and in particular not to impose movement of the cam 4 to the extended position.
In a preferential embodiment, the trigger 14 is installed able to slide along the wire element 6 between the head 3 and the annular end 2a. The trigger 14 can be coupled to the cam 4 or to each cam 4 by an additional wire element 15. The additional wire element 15 can be a metal cable, a textile element or a wire element made from synthetic material, for example from plastic. The additional wire element 15 couples the cam 4 to the trigger 14 and enables a movement of the trigger 14 towards the annular end 2a to be translated into a movement of the cam 4 to the retracted position.
The camming clamping device has a spring 16 that is configured to bias the at least one cam 4 to the extended position. The spring 16 can be manufactured in any technology: it can be a coil spring operating in traction, in compression, in torsion or in flexion. It can also be a blade or a metal wire that is elastically deformed. In the absence of stress and obstacles, the spring 16 places the cam or cams 4 in the extended position. The force applied on the trigger 14 to move away from the head 3 corresponds to a force applied on the spring 16 to move the cam or cams 4 to the retracted position. In one embodiment, the spring 16 is fixed on the one hand to the cam 4 and on the other hand to the head 3. In another embodiment, the spring 16 is fixed on the one hand to a first cam 4 and on the other hand to a second cam 4 installed on another pivot shaft 13 than that of first cam 4. The clamping device can comprise as many springs 16 as cams 4 or as many springs 16 as pairs of cams 4.
In preferential manner, the camming clamping device comprises at least one rod 5 that extends from the head 3 in the direction of the annular end 2a, i.e. in the first direction XX. In the embodiments illustrated in
The rod 5 is hollow and is passed through by the wire element 6 to connect the annular end 2a with the head 3. In preferential manner, the rod 5 is more rigid than the wire element 6 perpendicularly to the XX direction thereby enabling the camming clamping device to be held by means of the rod 5 and the clamping device to be placed precisely in a crack in comparison with an equivalent device without the rod 5. In preferential manner, the rod 5 extends continuously from the head 3 up to the annular end 2a so as to provide a good mechanical strength when the clamping device is secured by the annular end 2a and the trigger 14. It is advantageous for the trigger 14 to be installed able to slide along the rod 5 and for the rod 5 to separate the wire element 6 and the trigger 14. The rod 5 enables the wire element 6 to be protected outside the head 3 up to the annular end 2a.
As illustrated in
The ring made from textile material can be a ring made of polyethylene of very high molar mass, for example made from a material marketed under the tradenames Dyneema® or Spectra®.
The strands of each leg 6b are extended on one side or the other to form a loop 6a or a connecting portion 6c. A loop 6a extends a strand by another strand of the same leg 6b. The connecting portion 6c extends a strand by a strand of another leg 6b. In other words, each strand connects one end of a loop 6a with the connecting portion 6c. The connecting portion 6c comprises at least four strands of the wire element 6. The connecting portion 6c comprises twice as many strands as the loops 6a. Preferentially, each strand of the connecting portion 6c is installed able to slide with respect to the others.
As illustrated in
The loops 6a are fixed to the head 3 and the connecting portion 6c delineates the through hole 8 of the annular end 2a. The strands of the wire element 6 constitute the mechanical continuity between the head 3 and the annular end 2a. This embodiment is particularly advantageous as attachment of the head 3 with the wire element 6 is performed using the loops 6a. There is no need to fix the wire element 6 to the head 3 with a knot, a splicing, stitching, crimping or any other technological step modifying the mechanical integrity of the wire element 6.
The wire element 6 at least partially delineates the through hole 8 of the annular end 2a by means of the connecting portion 6c thereby obviating the need to form a specific loop 6a by means of a knot, a splicing, stitching, crimping or any other technological step modifying the mechanical integrity of the wire element 6.
The wire element 6 has at least two loops 6a attached to the head 3, i.e. attached directly to the head 3, and that are connected by at least two strands that extend continuously along the rod 5 and delineate the through hole 8 of the annular end 2a. The wire element 6 that is annular constitutes the mechanical continuity of the clamping device. This technical solution is more advantageous than the one presented in the document U.S. Pat. No. 10,143,892 that uses a splicing step to form two loops 6a respectively designed for attaching the head 3 and for defining the through hole 8 of the annular end 2a.
To provide a good strength, the ring is preferentially devoid of knots in the legs 6b and/or in the head 3. The loops 6a are extended at their ends by strands that come from or extend up to the annular end 2a and not by a knot formed at the end of the wire element 6.
The rod 5 is passed through by at least four strands of the wire element 6 between the head 3 and the annular end 2a. The four strands are in mechanical continuity by means of the connecting portion 6c and the loops 6a. The connecting portion 6c constitutes the mechanical continuity between the legs 6b.
Preferentially, the seam is located in the connecting portion 6c to limit the space occupation in the head 3 or close to the head 3.
Each loop 6a present in the head 3 is fixed to the head 3. Preferably, each attachment point between a loop 6a and the head 3 allows the wire element 6 to slide with respect to the head 3. When the wire element 6 is placed under tension, the tensile stress balance out between the strands due to sliding of the loops 6a. Preferably, the connecting portion 6c allows the different strands to slide with respect to one another to facilitate balancing of the forces.
Application of a tensile stress between the head 3 and the annular end 2a has the effect of stressing the wire element 6 and in particular the at least four strands of the wire element 6 that connect the head 3 to the annular end 2a. Increasing the number of strands enables a better trade-off to be achieved between the tensile strength in the XX direction, the space occupation inside the rod 5 and the flexibility perpendicularly to the XX direction.
The document US 2004/0035992 uses a loop 6a made of a strap that is installed flexible in a hollow rod. The maximum length of the loop 6a corresponds substantially to half the length of the strap. When the loop 6a is manufactured, a discrepancy exists on the cut length of the strap and on the length/position of the seam with respect to the required value. When several loops 6a are made, this results in a dispersion of the length of the loop 6a around of a target value. Pending use, the camming clamping device is hung by the strap. This results in the deviations regarding the length of the loop 6a leading to the camming clamping device not being as identical and interchangeable as expected, which can complicate extraction of the camming clamping device. The use of a wire element folded to form a U-shape has the effect of dividing at least by two the final result of the manufacturing uncertainty on the final length between attachment point 9 with the head 3 and the annular end.
Document U.S. Pat. No. 10,143,892 uses a single ring made from textile material formed by splicing. There again, in comparison with the prior art, the use of a wire element folded to form a U-shape has the effect of dividing by two the final result of the manufacturing uncertainty on the final length between attachment point 9 with the head 3 and the annular end 2a. It is also important to recall that the splicing step is long and costly in comparison with securing by a single seam where the two strands are arranged on one another and not in one another, i.e. without splicing.
In
Different embodiments are possible to attach the loops 6a of the wire element 6 with the head 3.
In a particular embodiment, the head 3 has at least one anchorage 9, for example an anchorage shaft. The loops 6a are attached to the at least one anchorage 9 to constitute the mechanical continuity between the head 3 and the wire element 6. Preferentially, the wire element 6 passes round the anchorage 9 to constitute the mechanical continuity with the annular end 2a. More preferentially, the loop 6a throttles the anchorage 9 to constitute the mechanical continuity.
In the embodiments illustrated in
It is particularly advantageous to have an anchorage 9 installed removable with respect to the head 3 so as to have a wire element 6 that is easily replaceable. Removal of the anchorage 9 eliminates the attachment between the wire element 6 and the head 3 thereby enabling the wire element 6 to be replaced.
It is advantageous for the anchorage 9 to be an anchorage shaft, i.e. a rod 5 that is inserted in the body 1a to secure the loops 6a. The anchorage shaft advantageously has a circular cross-section and advantageously a smooth surface.
For example, the anchorage shaft is fixed to the body 1a of the head 3 by screw-fastening, crimping, or riveting. The anchorage shaft extends mainly in a direction perpendicular to the first direction XX.
To replace the wire element 6, the anchorage 9 is disassembled, and a pull is exerted on the wire element 6 in the first direction XX. According to the particular case, the rod 5 is kept or the rod 5 is replaced. A new wire element 6 is installed with the loops 6a that are inserted in the head 3. The anchorage 9 or a new anchorage 9 passes through the loops 6a and is fixed to the head 3 to attach the wire element 6 with the head 3. Replacement of the wire element 6 is easy and does not require any operation on cams 4, the pivot shaft or shafts 13 or on the trigger 14.
In a particular embodiment, the rod 5 has an adjustable length in the XX direction. Adjustment of the length enables an increased length of the wire element 6 with respect to the rod 5 to be provided in the assembly phase. Once the loops 6a have been attached to the head 3, the length of the rod 5 is increased to absorb the excess wire element 6. This provides a better ergonomy between the head 3 and the annular end 2a without modifying the tensile strength between the head 3 and the annular end 2a.
The rod 5 with adjustable length can be a telescopic rod. Other embodiments are however possible.
In preferential manner, the annular end 2a is provided with a stiffener 17 that at least partly defines the shape of the annular end 2a. The stiffener 17 defines a shape that is or is close to that of a ring. The stiffener 17 is hollow. The stiffener 17 is passed through by the wire element 6 which defines the connecting portion 6c of the ‘U’. It is advantageous for the stiffener 17 to form the stop that comes into contact with the rod 5 and prevents the rod 5 from moving away from the head 3 beyond a threshold value. The material forming the stiffener 17 and the shape of the stiffener 17 define the relationship between the deformation of the stiffener 17 and the value of the compressive stress applied on the rod 5.
The embodiment illustrated in the figures makes disassembly easy in order to change at least one of the following components: the wire element 6, the rod 5 or the stiffener 17. In an advantageous embodiment, the rod 5 is diassemblable with respect to the head 3 which enables the rod 5 to be replaced when the latter is damaged. It is also possible to replace the stiffener 17 easily when the latter is damaged.
It is further possible to replace the rod 5 and the wire element 6 in order to adjust the length of the clamping device to a specific need. An extender of the trigger 14 can then be envisaged if the length of the rod 5 and of the wire element 6 is increased considerably.
The rod 5 is coupled mechanically to the head 3. The stiffener 17 is coupled to the rod 5. It is advantageous for the rod 5 to allow a part of the stiffener 17 to be inserted. It is advantageous for the stiffener 17 to surround the wire element 6 continuously from a first end that comes up against the stop formed by the rod 5 up to a second end that comes up against the stop formed by the rod 5. The wire element 6 is completely protected in the salient portion of the rod 5 that defines the annular end 2a.
In a particular embodiment, the rod 5 has a tapered end facilitating formation of a ring of considerable size in the annular end 2a.
The rod 5 is preferentially made from polymer material so as to be able to be flexible in one or more directions perpendicular to the first direction XX.
In the illustrated embodiments, the camming clamping device presents four cams 4. It is possible to use more or less cams 4. The configurations illustrated for installation of the wire element 6 are applicable on clamping devices that comprise one, two, three, four or more cams 4. The number of cams 4 can be even or odd. The cams 4 are preferentially made from metallic material, for example from aluminium alloy or from steel.
The embodiments illustrated in
The document US 2004/0035992 discloses a camming chock that is provided with a single strap ring. The ring is passed through by the pivot shaft of the cams and extends through the hollow rod to open onto the other side of the rod. The strap ring is installed without tension so that the strap end can exit at the level of the head 3 and be damaged. To place the chock in a crack, the rod has to be held placing the index finger and middle finger on the two ends of the trigger and installing the thumb against the end of the rod opposite the head 3. As the strap is installed free, it is to be expected that the thumb will press the two thicknesses of strap against the end of the rod. This configuration is not practical and leads to premature wear of the strap that is systematically pressed against the rod.
It is also apparent from the teaching of the document US 2004/0035992 that replacement of the strap ring necessarily requires the pivot shaft to be disassembled, which implies a good mastery of the reassembly process. As an alternative, the strap is cut and a new strap is then inserted before a stitching step is performed that will define the ring constituting the mechanical continuity.
There again, the stitching process has to be mastered perfectly, which makes a maintenance operation difficult for the final user to perform. No configuration exists in the prior art enabling the final user to fully master maintenance of a camming chock. It should also be emphasized that the variation of length of the textile loop 6a implies the use of springs to separate the annular end and the rod in order to stretch the wire element. It is apparent from the configuration illustrated in the document US 2004/0035992 that replacement of the textile loop 6a requires a splicing step to be performed after the two springs have been installed, which makes a strap replacement operation almost impossible for an average user.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2214297 | Dec 2022 | FR | national |
