US20050217748A1

US20050217748A1 - Shock absorbing rope

Info

Publication number: US20050217748A1
Application number: US11/086,821
Authority: US
Inventors: Isao Ikegami
Original assignee: YKK Corp
Current assignee: YKK Corp
Priority date: 2004-03-30
Filing date: 2005-03-22
Publication date: 2005-10-06
Also published as: JP2005281923A

Abstract

The invention provides a shock absorbing rope, in which a rope body shaped in a long tube formed to be elongated in a longitudinal direction thereof and a core member arranged inside of the tube of the rope body in a eased state are formed independently and separately from each other; the both ends of the rope body and the both ends of the core member in the longitudinal direction thereof are fixed with each other; and a length of the rope body in a contraction state is shorter than a length of the core member that is not in the eased state and the core member is arranged in the tube of the rope body in the eased state, and the rope body can be elongated longer than the length of the core member that is not in the eased sate.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to a shock absorbing rope whereby an ideal shock absorbing property for alleviating a shock given to a human body can be acquired. Particularly, the present invention relates to the shock absorbing rope whereby oscillation due to a reaction force after the shock can be attenuated so as to be made smaller.
2. Description of the Related Art
Conventionally, for example, at a high working site such as a highrise building and a high scaffolding or the like where a worker is damaged when he or she falls down, the worker generally wears a shock absorbing rope while doing the work standing on the scaffolding.
As an example of such a shock absorbing rope worn by the worker, for example, a woven webbing having a shock absorbing property is suggested (for example, refer to U.S. Pat. No. 6,085,802). A shock absorbing woven webbing 100 described in U.S. Pat. No. 6,085,802 has two separate regions as shown in FIG. 6, one is woven in succession to a first woven strap 101 and other is woven in succession to a tubular webbing 102. A material of this shock absorbing webbing 100 is composed of Kevlar (registered trademark), nylon, and polyester and a combination thereof.
The first woven strap 101 forms a flat tubular web by weaving a coupling thread 103 simultaneously on an upper side layer and a lower side layer of a tubular member to be formed in succession from a warp thread and a weft thread. One tubular webbing 102 forms a tubular web by weaving the tubular member in succession from the same warp thread and the same weft thread composing the warp thread and the weft thread of the first woven strap 101. In this tubular webbing 102, a filling thread 104 continued to the coupling thread 103 is not woven into each other on the upper side layer and the lower side layer of the tubular webbing 102 but the filling thread 104 is arranged inside of the tubular webbing 102 as a filling member.
Further, the woven webbing 100 forms a double layer part 106 by inserting an end portion 105 arranged in the vicinity of a part where the first woven strap 101 ends inside of the tubular webbing 102 and turning back a portion of the tubular webbing 102 to be doubly folded. Thereby, a length of the tubular webbing 102 including a double layer part 106 is set to be longer than that of the filling thread 104 arranged inside of the tubular webbing 102. Elasticity of this filling thread 104 is set to be larger than that of the tubular webbing 102.
The filling thread 104 is arranged so as to be freely elongated inside of the tubular webbing 102 as a tension is applied to the woven webbing 100. A material of the coupling thread 103 and the filling thread 104 has an elongation ratio of 61% having the minimum load for starting the elongation of 3.56 KN and the material is made of a nylon resin material, a part of which is directed.
A terminal end 107 of the filling thread 104 is attached to a terminal end 108 of the tubular webbing 102 by using a proper method. These terminal ends 107 and 108 are attached while folded so as to form a loop to which a connecting fitting is attached. The tubular webbing 102 at one side of the first woven strap 101 and an end 109 at the opposite side thereof are attached while folded so as to form a loop to which the connecting fitting is attached as same as in the terminal end 108 of the tubular webbing 102.
Elasticity of the filling thread 104 arranged inside of the tubular webbing 102 is larger than that of the tubular webbing 102 woven by the warp thread and the weft thread as described above and the length of the filling thread 104 is short. Therefore, it is possible to elongate the filling thread 104 to the length that is limited by the length of the tubular webbing 102 woven by the warp thread and the weft thread.
Accordingly, as soon as a tension is applied in a direction shown by a reference symbol F in FIG. 6, the filling thread 104 is elongated. When the filling thread 104 is elongated to the length limited by the length of the tubular webbing 102, the folded double layer part 106 of the tubular webbing 102 is released so as to form the tubular member of a single layer. Thereby, absorbing the energy of falling, the woven webbing 100 supports the entire load.
In the meantime, the woven webbing 100 described in U.S. Pat. No. 6,085,802 absorbs the shock when the worker falls due to the elongation of the filling thread 104 and the tubular webbing102. Therefore, when the woven webbing 100 is elongated to a scheduled length, the shock due to falling can be controlled. However, after being elongated with a force applied, the woven webbing 100 is contracting in a direction opposite to the elongation direction from the last elongated position. The entire woven webbing 100 jumps and eases up due to this reaction of contraction, and then, repeating elongation again, the oscillation due to elongation and easing up is generated. Therefore, when the woven webbing 100 eases up after elongation, this results in applying of an intense reaction force to the worker.
Thus, the conventional woven webbing 100 has a defect such that a jumping phenomenon occurs. However, the conventional woven webbing 100 has a structure such that the falling energy is absorbed when the length of the webbing 100 is elongated. Therefore, this structure has a problem such that the oscillation due to the reaction force after the shock of the webbing 100 cannot be made smaller by immediately attenuating it.
In addition, the conventional woven webbing 100 is formed by an integral woven structure that the first woven strap 101 and the tubular webbing 102 are continuously formed as described above. Further, the webbing 100 forms the double layer part 106 by inserting the end portion 105 arranged in the vicinity of the part where the first woven strap 101 ends inside of the tubular webbing 102 and turning back the portion of the tubular webbing 102 to be doubly folded. Therefore, this involves a problem such that manufacturing of the woven webbing 100 takes a lot of trouble and this leads to increase of its manufacturing cost or the like.

SUMMARY OF THE INVENTION

The present invention has been made taking the foregoing problems into consideration and an object of which is to provide a shock absorbing rope of a simple structure whereby an ideal shock absorbing property for alleviating a shock given to a human body can be acquired and an attenuation efficiency that oscillation due to a jumping phenomenon after the shock can be attenuated so as to be made smaller is enhanced.
The invention of a main aspect may include a shock absorbing rope comprising: a rope body shaped in a long tube that is formed to be elongatable in a longitudinal direction thereof and a long core member that is arranged inside of the tube of the rope body, wherein both ends of the rope body in the longitudinal direction thereof and both ends of the core member are fixed with each other, a length of the rope body in a contraction state is shorter than a length of the core member that is not in an eased state and the core member is arranged in the tube of the rope body in the eased state, and the rope body can be elongated longer than the length of the core member that is not in the eased state.
Accordingly, it is possible to separately form a rope body shaped in a long tube that is formed to be elongated in a longitudinal direction thereof and a core member that is inserted inside of the tube of the rope body independently from each other. Further, in the shock absorbing rope according to the present invention, the core member that is in an eased state can be arranged inside of the tubular part of the rope body that is contracted. In addition, in the shock absorbing rope according to the present invention, a length of the rope body that is contracted can be made shorter than a length of the core member that is not in an eased state and the ends at the both sides of the main body of the rope in a longitudinal direction thereof and the ends at the both sides of the core member can be secured with each other. Further, in the shock absorbing rope according to the present invention, the rope body can be elongated longer than the length of the core member that is not in an eased state.
Preferably, the rope body can be elongated and contracted in the longitudinal direction thereof combined with change of a configuration due to displacement of a composition thread constituting the rope body, and the length of the core member that is not in the eased state and the length of the rope body that is elongated in the longitudinal direction thereof in accordance with the change of the configuration are set to be substantially the same.
Thereby, the rope body and the core member can be elongated in the same lengths against a shock load or the like, and this makes it possible to support the shock load or the like by both of the rope body and the core member.
Preferably, a bearable load of the rope body that is elongated to a maximum is set to be heavier than that of the core member that is elongated to the maximum, and a total sum of the bearable load of the rope body in the maximum elongation and the bearable load of the core member in the maximum elongation is set to be heavier than the maximum load when a shock is given to the rope body and the core member.
If a tension is affected on the rope body and the core member, the rope body is elongated to the length when the core member is not in an eased state due to change of the configuration of its composition thread. When the rope body is elongated to the length when the core member is not in an eased state, the tension is affected on the composition thread constituting the core member and the composition thread of the core member starts to elongate. As soon as the composition thread of the core member starts to elongate, the rope body is continuously elongating due to change of the configuration of the composition thread thereof. After that, the rope body is elongated continuing to change in the configuration in accordance with elongation due to the composition thread of the rope body together with elongation of the composition thread of the core member.
Thus, according to the shock absorbing rope of the present invention, in a series of a shock absorbing process, a step of elongation due to change of the configuration of the composition thread of the rope body, a step of elongation due to change of the configuration of the composition thread of the rope body and elongation due to elongation of the composition thread of the core member, and a step of elongation due to elongation of the composition threads of the core member and the rope body are carried out sequentially and continuously. In other words, it is possible to absorb the shock energy sequentially by three steps. Therefore, it is possible to absorb the shock energy to be added to the rope body and the core member step by step, so that the entire shock load can be supported by the rope body and the core member. In the meantime, in a series of the shock absorbing process, before the step that the composition thread of the core member is elongated, the step that the composition thread of the rope body starts to elongate may start.
According to the shock absorbing rope of the present invention, the shock force can be alleviated step by step by the rope body and the core member, so that it is possible to enhance a control operation to absorb the shock energy and attenuation efficiency capable of immediately attenuating the oscillation after the shock and making it smaller.
When the worker falls down who wears the shock absorbing rope, for example, upon working at the high working site, generally a contracting force is generated on each composition threads of the rope body and the core member after the rope body and the core member are elongated to the last elongation position. Due to the reaction force of contraction, a pulling-up force to pull up the worker is affected on the worker who falls down. However, according to the shock absorbing rope of the present invention, the pulling-up force is partially expensed for change of the configuration of the entire rope body, so that it is possible to make the shock force to the worker smaller.
In addition, even if falling of the worker due to the load starts again after pulling up of the worker due to contraction of the rope body and the core member, it is possible to enhance the absorbing efficiency of the falling energy and to largely attenuate the oscillation due to jumping by elongation of respective composition threads of the rope body and the core member in addition to change of the configuration of the rope body. Thereby, with a simple structure, it is possible to acquire an ideal shock absorbing property for alleviating a shock given to a human body.
In the meantime, it is preferable that the core member is made of a member that elongates in its longitudinal direction, but is not contracted in its length direction. For example, a member that can change irreversibly is preferable. Thereby, without generation of the pulling-up force due to contraction of the core member, the pulling-up force can be made smaller.
As described above, in the shock absorbing rope according to the present invention, the rope body and the core member are formed independently and separately. On a portion to affect the shock absorbing energy, removing a shock absorbing part such as a part that is sewn by plural threads and a part that is doubly folded, the shock absorbing rope can be formed without having a particular shock absorbing structure to absorb the shock by damage at the shock absorbing part. Thereby, it is possible to easily make a shock absorbing rope and stably acquire a shock absorbing rope of a high quality and a good class.
Preferably, the rope body has a hollow woven structure.
According to a typical example of the rope body, for example, the rope body can be composed of a hollow woven lot that plural composition threads are inclined in right and left screws in a longitudinal direction thereof with crossing each other. As a lot, for example, a solid forging lot can be used. As a fabric of the lot, for example, a lot of one thread, a lot of two threads, and a lot of three and more threads or a fabric of mixture thereof can be used. For example, one of the core members can be formed as a string and a band by weaving and knitting.
Other structural example of the rope body can be formed by, for example, a general hollow woven structure that is woven elongatable in a longitudinal direction of the rope body by using the warp thread and the weft thread. According to the hollow weaving method, for example, by separating a warp thread row into front and back sides and weaving by shuttling the weft thread in a spiral, a tubular fabric can be formed. The configuration of the rope body is not particularly limited, however, for example, the tubular part of the rope body can be formed in a spiral and in a gather or the like.
Generally, if the core member is elongated, at the maximum stop position, the rope jumping phenomenon occurs. However, since each of the plural composition threads can be made from a weaving structure such as a lot fabric and a hollow woven fabric that can be elongated in the longitudinal direction of the rope body according to the present invention as described above, bondage of respective composition threads is reduced and the rope body can be freely elongated and contracted in its longitudinal direction. As a result, the reaction force of the rope can be absorbed due to change of configuration of the rope body, and the reaction of the rope can be alleviated by a damper effect due to this change of configuration, so that the oscillation after absorption of the shock can be immediately attenuated so as to be made smaller. In addition, the rope body can be freely elongated and contracted in its longitudinal direction, so that damage of the rope body upon absorption of the shock can be reduced.
Preferably, the rope body is woven in a sate that a tension is applied to the composition thread constituting the rope body; when weaving the rope body, the configuration of the rope body is formed while being elongated to the maximum; and after weaving of the rope body, the configuration of the rope body is kept to be contracted in the longitudinal direction thereof.
When weaving the rope body, the configuration of the entire rope body can be formed with being elongated to the maximum. Then, the fabric is uniform in quality across its entire periphery and without damage of the configuration of the entire rope, it is possible to acquire the rope body with excellent measurement stability. After weaving of the rope body, the rope body can be preferably contracted. Further, the core member can be stored in the contracted rope body and the operator can easily do the work because the shock absorbing rope of the present invention does not tangle with the operator wearing the shock absorbing rope of the present invention and the rope is not an obstacle to the operation.
As the composition thread of the rope body, a synthetic fiber having a high intensity as the typical resin material can be used. As the typical resin material, a fiber made of polypropylene, polyester, and nylon or the like is available. When the tension is affected on the rope body, it is possible to secure breaking strength capable of supporting the entire load due to the structure of the rope body and it is possible to support the entire load by the rope body.
Preferably, the composition thread constituting the rope body partially includes an extensible rubber, and the extensible rubber is woven as a part of a warp thread.
Accordingly, it is possible to use the extensible rubber as a part of the composition thread constituting the rope body and the extensible rubber can be woven at the same time as weaving of the rope body as a part of the warp thread. In the extensible rubber, the width, the thickness, the sectional configuration, the arrangement location, and the number of arrangement or the like can be appropriately set with respect to the rope body. The weaving fabric of the extensible rubber is made arbitrarily. For example, it is not necessary that the extensible rubber straddles or crawl under a plurality of composition threads and it may straddle or crawl under one composition thread.
In addition, it is possible to make the rope body into the minimum contraction state by an extensible elasticity of the extensible rubber. Due to the extensible elasticity of the extensible rubber, preferable configuration stability can be given to the rope body. Therefore, the shock absorbing rope can be made into a preferable length for the working operator wearing the shock absorbing rope of the present invention. The extensible elasticity of the extensible rubber also can absorb the falling energy at a falling accident, for example, caused upon working at the high working site. In addition, a damper effect to attenuate the rope jumping phenomenon can be effected. In addition, when absorbing the shock, by breaking the extensible rubber, the shock energy can be absorbed.
Preferably, the composition thread constituting the rope body is composed of a synthetic fiber of a high intension.
Preferably, the composition thread of the core member is composed of a synthetic fiber of a high ductility.
Preferably, the core member has a structure of herringbone woven fabric or plain woven fabric to be formed in a narrow width tape.
As the composition thread of the core member, a synthetic fiber having a higher intension and a higher ductility (a higher toughness) than the material of the rope body can be used. As the typical resin material of the core member, a polyester fiber can be used. As the composition thread of the core member, a polyester fiber can be used as the typical resin material. The core member may be a fabric of weaving or knitting, however, it is preferable that the polyester fiber is woven in a narrow width tape. As the weaving fabric of the core member, a herringbone woven fabric or plain woven fabric are available. By applying a substantially constant load to the core member, the core member can be elongated and by securing a function to absorb the shock energy due to the elongation, it is possible to make the shock given to the human body comparatively small.
Preferably, the shock absorbing rope comprises safety member for high altitude work having connecting fittings that are fixed to the both ends of the rope body and the core member in the longitudinal direction thereof, respectively.
The shock absorbing rope of the present invention can be effectively used as a safety member for a high working site having connecting fittings that are fixed to the both ends of the rope body and the core member in the longitudinal direction thereof respectively. The shock absorbing rope of the present invention can be used for all manufactures that are required to control the shock given to the human body. According to a usage example, for example, the shock absorbing rope according to the present invention can be widely applied to a climbing rope, a wire rope, a rope for bungee jump, a seat belt, a rope for a jump sack, and a fastening belt of a luggage or the like. The effects which the present invention exerts are considerably great.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pattern diagram of a perspective view showing a safety rope for working at a high site using a typical shock absorbing rope according to the present invention with partial cut (a first embodiment);
FIG. 2 is a pattern diagram of a partial plan view showing the rope (the first embodiment);
FIG. 3 is a pattern diagram of a partial perspective view showing a state in the middle of elongation of the rope with partial cut (the first embodiment);
FIG. 4 is a pattern diagram of a partial plan view showing a state of elongation of the rope (the first embodiment);
FIG. 5 is a pattern diagram of a sectional view showing other structural example of the rope (a second embodiment); and
FIG. 6 is a sectional view showing a conventional shock absorbing woven webbing.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the drawings, the preferred embodiments of the present invention will be described below.
(First Embodiment)
In FIG. 1, a reference numeral 10 is a pattern diagram showing a shock absorbing rope that is used as a safety member for working at the high working site having connecting fittings 40 that are fixed to the both ends of the shock absorbing rope in the longitudinal direction thereof, respectively. According to the illustrated example, a shock absorbing rope 10 forms a rope body 20 shaped in a flat and long tube and a core member 30 shaped in a narrow tape arranged inside of the rope body 20 in an eased state independently and separately from each other.
The rope body 20 is formed in a tubular hollow weaving having the core member 30 inserted through it. The both ends of the rope body 20 and the core member 30 in the longitudinal direction thereof are wrapped by the adhesive tape and the like to be formed in a taper while being elongated narrowly. The both ends of the rope body 20 and the core member 30 in the longitudinal direction thereof are folded so as to form a loop to attach the connecting fitting 40 thereto, are inserted in a gap 22 encircled by respective composition threads that are inclined in right and left with respect to a longitudinal direction of the rope body 20 with crossing each other, and are fixed by an appropriate fixing device.
As shown in FIGS. 2 to 4, the rope body 20 straddles two warp threads 21 as the composition thread, and then, the rope body 20 crosses the warp threads 21. 21 every other two so as to crawl under the next two warp threads 21, 21. Repeating this, respective warp threads 21 are alternately woven in a substantial S shape and in a substantial Z shape across the front and back sides of the rope body 20 in the longitudinal direction thereof. As this warp thread 21, being not limited particularly, however, a monofilament or a multifilament made of a polypropylene fiber having a high intension and a high durability can be used. Alternatively, as the warp thread 21, a monofilament or a multifilament made of a polyester fiber or a nylon fiber having a high intension and a high durability also can be used.
According to this first embodiment, the rope body 20 is composed of a solid forging lot in which the threads are inclined in right and left screws with respect to a longitudinal direction of the rope body 20 while crossing each other. As a fabric of the lot, for example, a lot of one thread, a lot of two threads, a lot of three threads, and a lot of four and more threads or a fabric of mixture thereof can be used.
When weaving the rope body 20, it is preferable that the warp thread 21 constituting the rope body 20 is woven while applying the tension thereto. When weaving the rope body 20, it is preferable that the shape of the rope body 20 is formed while being elongated to the maximum elongated length. Thereby, it is possible to prevent damage of the configuration of the rope body 20. Then, the fabric is uniform in quality across its entire periphery and it is possible to acquire the rope body with excellent measurement stability. After weaving of the rope body 20, the rope body 20 can be preferably contracted. Further, the core member 30 can be stored in the contracted rope body 20 and the operator can easily do the work because the shock absorbing rope 10 does not tangle with the operator wearing the shock absorbing rope 10.
In the shock absorbing rope 10 shown in the drawing, the warp threads 21 are inclined in a direction substantially orthogonal to a longitudinal direction of the rope body 20 when the adjacent warp threads 21 directed to the same direction contact each other as shown in FIG. 2 to be contracted in a first contacting state. On the other hand, in the shock absorbing rope 10 shown in the drawing, the warp threads 21 are inclined in a longitudinal direction of the rope body 20 when the adjacent warp threads 21 directed to the same direction are elongated along the longitudinal direction of the rope body 20 as shown in FIG. 4 to contact each other in a second contacting state.
According to such a weaving structure of this rope body 20, if the tension is affected on the rope body 20, a lot angle θ₂made by respective warp threads 21 crossing each other inclined in right and left to the longitudinal direction of the rope body 20 is changed so as to be smaller than a lot angle θ₁as shown in FIG. 2 and FIG. 4. Thereby, combined with the lot structure of the rope body 20, it is possible to sufficiently secure the breaking strength capable of supporting the maximum load upon the shock.
As a part of each warp thread 21 of the rope body 20, as shown in FIG. 3, a plurality of narrow extensible rubbers 23 are arranged in parallel at predetermined intervals. The both ends of this extensible rubber 23 in the longitudinal direction thereof are attached to the ends of the rope body 20 respectively. The extensible rubbers 23 are arranged in a vertical direction along the rope body 20 so as to crawl under respective warp threads 21 crossing at an angle to the longitudinal direction of the rope body 20 while being pressed down by the warp threads 21. The extensible rubber 23 is woven substantially linearly across the longitudinal direction of the rope body 20 at the same time of weaving of the rope body 20.
Due to the extensible elasticity of the extensible rubber 23, the rope body 20 can be freely elongated in the longitudinal direction thereof, and the rope body 20 can be made in the minimum contraction state as shown in FIG. 2 due to the extensible elasticity of the extensible rubber 23. Further, preferable configuration stability can be given to the rope body. In addition, the extensible rubber 23 can be also formed so as to absorb the shock energy by breaking it when absorbing the shock. In addition, it is also possible to have a damper effect for attenuating the rope jumping phenomenon. In the meantime, a plurality of extensible rubbers 23 are arranged in parallel inside of the rope body 20 to be woven in the warp thread every other two or three while being hidden by the warp thread. In the extensible rubber 23, the width, the thickness, the sectional configuration, the arrangement location, and the number of arrangement or the like can be appropriately set with respect to the rope body 20.
In the shock absorbing rope 10 of the present invention, it is preferable that the length of the rope body 20 in the contraction state as shown in FIG. 2 is set to be shorter than the length of the core member 30 when the core member 30 does not ease up, and it is preferable that the rope body 20 can be elongated longer than the length of the core member 30 when the core member 30 does not ease up. Combined with change of the configuration of the rope body 20 caused by relative change of the position of each warp thread 21 of the rope body 20, it is possible to form the rope body 20 to be elongatable in the longitudinal direction thereof. According to the illustrated example, it is possible to form the rope body 20 so that each warp thread 21 of the rope body 20 is changed from the configuration in the first contact state shown in FIG. 2 into the configuration in the second contact state shown in FIG. 4.
Further, it is preferable that the length of the core member 30 when it does not ease up is set to be substantially equal to the length of the rope body 20 when the rope body 20 is elongated in its longitudinal direction combined with change of configuration thereof due to displacement of the warp thread 21. According to the illustrated example, it is possible to set the length of the core member 30 to be substantially equal to the length of the rope body 20 in the second contact state that the adjacent warp threads 21 directed to the same direction contacting each other as shown in FIG. 4 from the length when the core member 30 eases up as shown in FIG. 1. As a result, the rope body 20 and the core member 30 can be elongated in the same length against the shock force due to falling to be applied to the rope body 20 and the core member 30 and the shock load can be supported by both of the rope body 20 and the core member 30.
For example, it is preferable that the core member 30 is woven in a narrow width tape. According to the present embodiment, the core member 30 can be composed of herringbone woven fabric as a woven fabric. Alternatively, the woven fabric of the core member 30 may be composed of the plain woven fabric. As the composition thread of the core member 30, being not limited, however, a monofilament or a multifilament made of a polypropylene fiber having a higher intension and a higher durability than the material of the rope body 20 can be used. Thereby, the core member 30 starts to be elongated when a certain load is applied thereto. This elongation makes it possible to secure a function to absorb the shock energy so as to make the shock applied to the human body comparatively small.
According to the shock absorbing rope 10 that has been formed as described above, it is preferable that a bearable load F1 in the maximum elongation state of the rope body 20 and a bearable load F2 in the maximum elongation state of the core member 30 satisfy a relation of F1>F2, (F1+F2)>F. However, the reference symbol F is the maximum load when the shock is applied to the rope body 20 and the core member 30. As the structure of the shock absorbing rope 10, being not limited, however, the shock absorbing load may be about 8.82 KN or less and the breaking strength may be about 22.246 KN or more. Thereby, it is possible to sufficiently secure both of the ideal shock absorbing function and fall preventing function.
When the tension due to falling is affected on the rope body 20 and the core member 30, the rope body 20 is elongated from the length in the first contact state shown in FIG. 2 to the length in the second contact state shown in FIG. 4 by change of the configuration due to displacement of each warp thread 21. If the length of the core member 30 arranged in an eased state inside the rope body 20 is elongated to the length when the core member 30 does not ease up by change of the configuration of the composition thread of the rope body 20, by applying the tension on the composition thread constituting the core member 30, the composition thread of the core member 30 starts to elongate. Subsequently, the composition thread of the core member 30 starts to elongate. Combined with start of elongation of the composition thread of the core member 30, the rope body 20 keeps elongating by change of the configuration of each warp thread 21. After that, combined with elongation of each warp thread 21 of the rope body 20 together with elongation of the composition thread of the core member 30, the rope body 20 keeps changing of the configuration and elongating.
Thus, the shock energy due to falling can be absorbed by three steps, namely, a step of elongation due to change of the configuration of each warp thread 21 of the rope body 20, a step of elongation due to change of the configuration of each warp thread 21 of the rope body 20 and elongation due to elongation of the composition thread of the core member 30, and a step of elongation due to elongation of each warp thread 21 of the rope body 20 and elongation of each composition thread of the core member 30. Therefore, it is possible to absorb the shock energy due to falling to be added to the rope body 20 and the core member 30 step by step, so that the entire falling load due to falling can be supported by the rope body 20 and the core member 30. In the meantime, it is obvious that, in a series of the shock absorbing process, before the step that the composition thread of the core member 30 is elongated, the step that each warp thread 21 of the rope body 20 starts to elongate may start.
Thus, according to the shock absorbing rope 10 of the present invention, the shock force due to falling to be added to the rope body 20 and the core member 30 can be alleviated step by step, so that it is possible to enhance a control operation to absorb the shock energy due to falling and attenuation efficiency capable of immediately attenuating the oscillation after the shock and making it smaller. Thereby, it is possible to secure an ideal shock absorbing performance to alleviate the shock that is given to the human body.
In the meantime, when the worker falls down who wears the shock absorbing rope 10 while working at the high working site, generally a contracting force is generated on each warp thread 21 of the rope body 20 and each composition thread of the core member 30 after the rope body 20 and the core member 30 are elongated to the last elongation position. Due to the reaction force of contraction, a pulling-up force to pull up the worker is affected on the worker who falls down.
According to the shock absorbing rope 10 of the present invention, by providing above described structures, the pulling-up force is partially expensed for change of the configuration of the rope body 20, so that it is possible to make the shock force to the worker smaller. In addition, even if falling of the worker due to his or her weight starts after pulling up of the worker due to contraction of the rope body 20 and the core member 30, it is possible to absorb the falling energy by elongation of each warp thread 21 of the rope body 20 and elongation of each composition thread of the core member 30 in addition to change of the configuration of the rope body 20. Thereby, it is possible to immediately attenuate the oscillation due to jumping.
In addition, if the rope body 20 and the core member 30 are elongated from the length of the first contact state shown in FIG. 2 to the length of the second contact state shown in FIG. 4 due to falling of the worker occurred at the high working site, a rope jumping phenomenon is generated at the maximum stop position. However, since each warp thread 21 of the rope body 20 is formed crossing at an angle to the longitudinal direction of the rope body 20, the rope body 20 can be freely contracted in the longitudinal direction thereof due to change of the configuration. As a result, the reaction force of the shock absorbing rope 10 can be absorbed due to change of configuration of the rope body 20, and the reaction of the shock absorbing rope 10 can be alleviated by a damper effect due to this change of configuration of the rope body 20, so that the oscillation after absorption of the shock due to falling can be immediately attenuated so as to be made smaller.
In the meantime, it is possible that the core member 30 is made of a member that elongates in its longitudinal direction, but is not contracted in its length direction. For example, a member that can change irreversibly is preferable. Thereby, without generation of the pulling-up force due to contraction of the core member 30, the pulling-up force can be made smaller.
In addition, by weaving each warp thread 21 of the rope body 20 crossing at an angle to the longitudinal direction of the rope body 20, the bondage between respective warp threads 21 is reduced and the rope body 20 can be freely elongated and contracted in the longitudinal direction thereof. Therefore, upon absorption of the shock, damage of the rope body 20 can be reduced. After absorbing the shock due to falling, the core member 30 can be exchanged by separating the rope body 20 and the core member 30 from each other. Thereby, the rope body 20 can be reused as a part of the shock absorbing rope 10.
According to the shock absorbing rope 10 of the present invention, as described above, the rope body 20 and the core member 30 are formed independently and separately. Thereby, on a portion to affect the shock absorbing energy due to falling, removing a shock absorbing part such as a part that is sewn by plural threads and a part that is doubly folded, the shock absorbing rope 10 can be formed without a particular shock absorbing structure to absorb the shock by damage at the shock absorbing part. Therefore, the rope body 20 and the core member 30 can be easily manufactured and this makes it possible to stably acquire the shock absorbing rope 10 of a high quality and a simple structure.
(Second Embodiment)
FIG. 5 a pattern diagram showing other example of the shock absorbing rope 10 according to the present invention. In the meantime, the same member names and the same reference numerals are given to the substantially same members as those in the first embodiment. Accordingly, the detailed description of these members will not be repeated here.
In this drawing, a basic configuration of the shock absorbing rope 10 is made of a general hollow woven fabric having two elastic rubbers 23 inserted on the front and rear surfaces of a long tubular rope body 20. The rope body 20 can be formed as a long tubular body by horizontally putting a weft thread row 24 into a warp thread row 21 of a synthetic fiber made of a resin material such as a polypropylene fiber, a polyester fiber, and a nylon fiber having a high intension and a high durability.
The elastic rubber 23 can be woven as a partial warp thread of the hollow woven part when weaving the rope body 20. The extensible rubber 23 is arranged so that it straddles one weft thread 24 and then, crawls under the next weft thread 24 crossing the weft thread 24 while being pressed down by the weft thread 24. The extensible rubber 23 is woven on the front and rear surfaces in the longitudinal direction of the rope body 20 while repeating this at the same time as weaving of the rope body 20. The elastic rubber 23 is set to be thicker than other weft threads 24.
In the meantime, the elastic rubber 23 is formed in a solid core, however, being not limited to this, the elastic rubber 23 may be formed in a hollow tube. In addition, as the warp thread 21 and the weft thread 24, the monofilament or the multifilament made of the synthetic fiber can be used. The rope body 20 is not limited to the illustrated example. For example, by using the warp thread and the weft thread, the rope body 20 can be formed from other hollow woven fabric forming a tubular fabric that is elongatable in the longitudinal direction. As a hollow weaving method, for example, a general weaving method to form a tubular fabric that is fastened at the both edges, for example, by separating the warp thread row into the front and rear sides and weaving the weft thread while repeating the weft thread in a spiral is available. The configuration of the rope body 20 is not particularly limited, however, for example, the tubular part of the rope body 20 can be formed in a coil or in a bellows or the like.
According to the shock absorbing rope 10 of this second embodiment, as in the first embodiment, in a series of a shock absorbing process, the shock applied to the rope body 20 and the core member 30 can be absorbed step by step by three steps, namely, a step of elongation due to change of the configuration of the composition thread of the rope body 20, a step of elongation due to change of the configuration of the composition thread of the rope body 20 and elongation due to elongation of the composition thread of the core member 30, and a step of elongation due to elongation of the composition threads of the rope body 20 of the core member 30, respectively. Thereby, it is possible to enhance a control operation to absorb the shock energy and attenuation efficiency capable of attenuating the oscillation after the shock and making it smaller.
As being obvious from the above descriptions, according to the respective embodiments, the rope body 20 of a general hollow woven fabric that is woven so as to be elongatable in the longitudinal direction of the rope body 20 and the core member 30 made of a weaving structure such as a herringbone woven fabric in a narrow width tape or the like are combined. However, the present invention is not limited to this. It is obvious that the weaving or knitting of the core member 30 can be selected and combined, for example, depending on the material and the fabric structure of the rope body 20, and an object of the present invention can be sufficiently attained. Accordingly, it is obvious that the present invention is not limited to the respective embodiments and various modifications will be possible within the scope mentioned in the present invention.
The shock absorbing rope 10 as the object of the present invention, a safety rope for a high working site is described as an example, however, the present invention is not limited to this. For example, all shock absorbing ropes to be applied to various manufactures such as a climbing rope, a wire rope, a rope for bungee jump, a seat belt, a rope for a jump sack, and a fastening belt of a luggage or the like may be targeted.

Claims

1. A shock absorbing rope comprising:

a rope body shaped in a long tube that is formed to be elongatable in a longitudinal direction thereof and a long core member that is arranged inside of the tube of the rope body,

wherein both ends of the rope body in the longitudinal direction thereof and both ends of the core member are fixed with each other,

a length of the rope body in a contraction state is shorter than a length of the core member that is not in an eased state and the core member is arranged in the tube of the rope body in the eased state, and

the rope body can be elongated longer than the length of the core member that is not in the eased state.

2. The shock absorbing rope according to claim 1,

wherein the rope body can be elongated and contracted in the longitudinal direction thereof combined with change of a configuration due to displacement of a composition thread constituting the rope body, and

the length of the core member that is not in the eased state and the length of the rope. body that is elongated in the longitudinal direction thereof in accordance with the change of the configuration are set to be substantially the same.

3. The shock absorbing rope according to claim 1,

wherein a bearable load of the rope body that is elongated to a maximum is set to be heavier than that of the core member that is elongated to the maximum, and

a total sum of the bearable load of the rope body in the maximum elongation and the bearable load of the core member in the maximum elongation is set to be heavier than the maximum load when a shock is given to the rope body and the core member.

4. The shock absorbing rope according to claim 1,

wherein the rope body has a hollow woven structure.

5. The shock absorbing rope according to claim 1,

wherein the rope body is woven in a sate that a tension is applied to the composition thread constituting the rope body; when weaving the rope body, the configuration of the rope body is formed while being elongated to the maximum; and after weaving of the rope body, the configuration of the rope body is kept to be contracted in the longitudinal direction thereof.

6. The shock absorbing rope according to claim 1,

wherein the composition thread constituting the rope body partially includes an extensible rubber, and the extensible rubber is woven as a part of a warp thread.

7. The shock absorbing rope according to claim 1,

wherein the composition thread constituting the rope body is composed of a synthetic fiber of a high intension.

8. The shock absorbing rope according to claim 1,

wherein the composition thread of the core member is composed of a synthetic fiber of a high ductility.

9. The shock absorbing rope according to claim 1,

wherein the core member has a structure of herringbone woven fabric or plain woven fabric to be formed in a narrow width tape.

10. The shock absorbing rope according to claim 1,

wherein the shock absorbing rope comprises safety member for high altitude work having connecting fittings that are fixed to the both ends of the rope body and the core member in the longitudinal direction thereof, respectively.