JP5851859B2 - Shock-absorbing structure of cable-shaped body and protective fence - Google Patents

Description

  The present invention relates to a shock absorbing structure for a cable-like body for absorbing the impact force when the impact force is applied to a cable-like body constructed between supports such as columns and embankments, and a protective fence using the same. Is.

  Conventionally, various structures have been proposed as an impact absorbing structure that absorbs an impact force when the impact force is applied to a cord-like body installed between support bodies such as support columns.

  In Patent Document 1 and Patent Document 2, a shock absorbing structure having a sandwiching structure is proposed. This is because when a plurality of plate members are sandwiched between a plurality of plate members, a plurality of plate members are tightened with bolts, caulking, etc., and when an impact force is applied to the cable members, It is structured to absorb shocks by friction between the two.

  Moreover, in patent document 3, the shock absorption structure used for the connection part of the cord-shaped body arrange | positioned in series is proposed. This includes an outer cylinder attached to the end of one cable-shaped body, a resistor housed in the outer cylinder, connected to the end of the other cable-shaped body, and a resistor and an outer cylinder. And an elastic body that compresses and absorbs an impact force according to the movement of the other cord-like body. Thereby, when an impact force is applied, the elastic body is compressed in accordance with the movement of the cord-like body, and the resistor is forced to pass through the elastic body to absorb the shock.

JP 2003-301418 A JP 2010-144433 A JP 2009-150097 A

  However, in the impact absorbing structure having a sandwiching structure as in Patent Document 1 or the like, a structure other than the pressing surface of the plate member pressing the cord-like body has a structure that hardly causes friction. For this reason, in this structure, the pressing surface of the plate material is worn due to friction, so that the frictional force gradually decreases, and there is a problem that a stable shock absorbing performance cannot be obtained continuously. In addition, this structure is a structure that adjusts the shock absorbing performance by adjusting the tightening force with bolts or caulking. However, in this structure, it is necessary to finely adjust the tightening force with bolts etc. to obtain the desired shock absorption performance, and the on-site workers must adjust the tightening force with bolts etc. Is likely to occur. As a result, this structure has a problem that it is difficult to easily obtain a desired shock absorbing performance.

  Moreover, since the shock absorbing structure as in Patent Document 3 can be attached only to the end portion of the cord-like body, there is a problem that the number of attachments cannot be increased when the length of the cord-like body is long. . Moreover, when the installation interval of the shock absorbing structure is shorter than the entire length of the cord-like body, it is necessary to cut the cord-like body so that the cord-like body is shortened.

  Therefore, the present invention has been devised in view of the above-mentioned problems, and the object of the present invention is to obtain a stable shock absorbing performance continuously with respect to the impact force, and to obtain a desired shock absorbing performance. It is another object of the present invention to provide a shock-absorbing structure for a cord-like body that can easily obtain the above-described problem and that can advantageously solve the above-described problems.

  In order to solve the above-mentioned problems, the present inventor has invented the following shock-absorbing structure of a cord-like body after intensive studies.

The shock absorbing structure for a cord-like body according to the first aspect of the present invention is an impact absorbing structure for absorbing an impact force when a falling object collides with a cord-like body constructed between supports, and is provided with a slit. An impact absorbing member and a slit width holding portion for holding the slit width of the slit, and the slit includes an inlet portion in which the cord-like body is disposed, and the inlet when the impact force is applied. An energy absorbing portion extending in a direction in which the cord-like body can move from the portion, and the energy absorbing portion is formed with a slit width smaller than the diameter of the cord-like body, and the slit width holding portion It is characterized by being formed in a taper shape so that the slit width becomes narrower as it goes away from the slit in the longitudinal direction.

  According to a second aspect of the present invention, there is provided a shock absorbing structure for a cord-like body according to the first invention, wherein the slit is located at a portion where the cord-like body starts to enter the energy absorbing portion when the impact force is applied. It further has a guide portion formed in a tapered shape so that the slit width becomes narrower toward the front side.

  The cord-shaped shock absorbing structure according to a third aspect of the present invention is the first aspect or the second aspect of the present invention, wherein the slit width holding portion is provided with an interval in the slit longitudinal direction with respect to the slit, and the energy absorbing portion Is characterized in that it is formed in a tapered shape so that the narrowest part where the slit width is the narrowest is provided at a substantially central position of the slit width holding part adjacent in the slit longitudinal direction.

A shock absorbing structure for a cord-like body according to a fourth aspect of the present invention is an impact absorbing structure for absorbing an impact force when a falling object collides with a cord-like body installed between supports, and is provided with a slit. An impact absorbing member and a slit width holding portion for holding the slit width of the slit, and the slit includes an inlet portion in which the cord-like body is disposed, and the inlet when the impact force is applied. An energy absorbing portion extending in a direction in which the cord can move from the portion, and the energy absorbing portion is formed to have a slit width smaller than the diameter of the cord, and the slit has the impact force In the portion where the cord-like body begins to enter the energy absorbing portion when the action is applied, it further has a guide portion formed in a tapered shape so that the slit width becomes narrower toward the front side in the approach direction. To.

A shock absorbing structure for a cord-like body according to a fifth aspect of the present invention is an impact absorbing structure for absorbing an impact force when a fallen object collides with a cord-like body installed between supports, wherein the cord-like body A shock absorbing member in which a loop portion having a ring shape is wound, and the cord which is provided in the shock absorbing member along a portion where the loop portion of the cord-like body is wound and forms the loop portion A slit through which the rod-like body is inserted, and a slit width holding portion that holds the slit width of the slit, the slit has an energy absorbing portion that is formed with a slit width smaller than the diameter of the cord-like body, The energy absorbing portion is formed in a taper shape so that a slit width on a side where the loop portion inserted through the slit is contracted is narrowed.

  According to a sixth aspect of the present invention, there is provided a shock absorbing structure for a cord-like body according to the fifth invention, wherein the slit is in a direction in which the cord-like body starts to enter the energy absorbing portion when the impact force is applied. It has the guide part formed in the taper shape so that a slit width may narrow as it goes to the front side, It is characterized by the above-mentioned.

  The shock absorbing structure for a cord-like body according to a seventh aspect of the present invention is the fifth aspect or the sixth aspect, wherein the slit width holding portion is provided with a space in the slit longitudinal direction with respect to the slit, and the energy absorbing portion Is characterized in that it is formed in a tapered shape so that the narrowest part where the slit width is the narrowest is provided at a substantially central position of the slit width holding part adjacent in the slit longitudinal direction.

A shock absorbing structure for a cord-like body according to an eighth aspect of the present invention is an impact absorbing structure for absorbing an impact force when a falling object collides with a cord-like body installed between supports, wherein the cord-like body A shock absorbing member in which a loop portion having a ring shape is wound, and the cord which is provided in the shock absorbing member along a portion where the loop portion of the cord-like body is wound and forms the loop portion A slit through which the rod-like body is inserted, and a slit width holding portion that holds the slit width of the slit, and the slit has an energy absorbing portion formed with a slit width smaller than the diameter of the cord-like body, and the impact A guide portion formed in a tapered shape so that the slit width becomes narrower toward the front side in the approach direction at a portion where the cord-like body begins to enter the energy absorbing portion when a force is applied; And features.

  A protective fence according to a ninth aspect of the present invention includes a support body composed of a plurality of support columns erected at intervals in the lateral direction, and a cord-like body erected between the plurality of support bodies. The body is characterized by using the cord-like shock absorbing structure according to any one of the first to eighth inventions.

  According to the 1st invention-the 4th invention, even if the slit side surface of a slit wears, it becomes possible to exhibit the stable shock absorption performance continuously with respect to an impact force. Further, in order to obtain the desired shock absorption performance, it is not necessary to finely adjust the tightening force with bolts or caulking, and the desired shock absorption performance can be easily obtained.

  In particular, according to the first to third inventions, since the slit width is tapered so that the slit width decreases as the distance from the slit width holding portion increases in the slit longitudinal direction, the movement resistance of the cord-like body is reduced in the slit longitudinal direction. It is possible to suppress the fluctuation, and as a result, it is possible to exhibit the impact absorbing performance over the entire length in the slit longitudinal direction of the energy absorbing portion.

  Further, according to the second and fourth inventions, since the guide portion formed in a taper shape is provided so that the slit width becomes narrower toward the front side in the approach direction to the energy absorbing portion, the cord-like body is impacted. The entry resistance to the energy absorbing portion in the initial stage where the force is applied is reduced, and a desired impact absorbing performance can be exhibited even with a small impact force.

  Further, according to the fifth to eighth inventions, even if the slit side surface of the slit is worn, it is possible to continuously exhibit a shock absorbing performance that is stable against the impact force. Further, in order to obtain the desired shock absorption performance, it is not necessary to finely adjust the tightening force with bolts or caulking, and the desired shock absorption performance can be easily obtained. Further, after the cord-like body is moved in the slit longitudinal direction by the impact force, it is possible to lengthen the construction length of the cord-like body between the supports. Since the shock absorbing member can be attached to any part of the cord-like body, it can be used without being restricted by the length of the cord-like body.

  In particular, according to the fifth to seventh inventions, since the slit width is tapered so that the slit width is narrowed away from the slit width holding portion in the slit longitudinal direction, the movement resistance of the cord-like body is the slit longitudinal direction. It is possible to suppress the fluctuation, and as a result, it is possible to exhibit the impact absorbing performance over the entire length in the slit longitudinal direction of the energy absorbing portion.

  Further, according to the sixth and eighth inventions, since the guide portion formed in a tapered shape is provided so that the slit width becomes narrower toward the front side in the approach direction to the energy absorbing portion, the cord-shaped body is impacted. The entry resistance to the energy absorbing portion in the initial stage where the force is applied is reduced, and a desired impact absorbing performance can be exhibited even with a small impact force.

(A) is a top view which shows the structure of the guard fence in which the impact-absorbing structure which concerns on 1st Embodiment is used, (b) is the rear view. (A) is side sectional drawing which shows the structure of the impact-absorbing structure which concerns on 1st Embodiment, (b) is the rear view. It is an expanded side sectional view showing what expanded the composition of the shock absorption structure concerning a 1st embodiment. (A) is a top view for demonstrating the effect of the impact-absorbing structure which concerns on 1st Embodiment, (b) is the side sectional drawing. It is a figure for demonstrating the effect of the shock absorption structure which concerns on this invention. It is another figure for demonstrating the effect of the shock absorption structure which concerns on this invention. (A) is an expanded side sectional view which shows what expanded the structure of the impact-absorbing structure which concerns on 2nd Embodiment, (b) is the rear view. (A) is an enlarged plan view which shows the structure of the impact-absorbing structure which concerns on 3rd Embodiment, (b) is AA sectional view taken on the line of (a), (c) is the impact-absorbing which concerns on 3rd Embodiment. It is an expanded side sectional view which shows what expanded the structure of the structure. (A) is an enlarged plan view for demonstrating the effect of the impact-absorbing structure which concerns on 3rd Embodiment, (b) is the top view. (A) is an enlarged plan view which shows the structure of the impact-absorbing structure which concerns on 4th Embodiment, (b) is an enlarged plan view for demonstrating the effect, (c) is 4th Embodiment. It is an expanded side sectional view which shows what expanded the structure of the shock absorption structure which concerns. (A) is an expanded side view which shows the structure before the movement of the cord-shaped body of the impact-absorbing structure which concerns on 5th Embodiment, (b) is an enlarged side view which shows the structure after the movement, (c) These are the expanded plane sectional views for demonstrating the effect. (A) is a top view which shows the structure of the guard fence in which the impact-absorbing structure which concerns on 6th Embodiment is used, (b) is the back view. It is a plane sectional view showing the composition of the shock absorption structure concerning a 6th embodiment. (A) is side sectional drawing which shows the structure of the impact-absorbing structure which concerns on 6th Embodiment, (b) is the front view. (A) is an expanded view which shows typically what developed the shock absorption member used for the shock absorption structure concerning a 6th embodiment along the peripheral direction, and (b) is a plane sectional view of the shock absorption member. It is. (A) is a side view of the impact-absorbing member used for the impact-absorbing structure which concerns on 6th Embodiment, (b) is the front view. (A) is a side view of the impact-absorbing member used for the impact-absorbing structure which concerns on 7th Embodiment, (b) is the front view. (A) is an expanded view which shows typically what developed the shock absorption member used for the shock absorption structure concerning a 7th embodiment along the peripheral direction, and (b) is a plane sectional view of the shock absorption member. It is. It is a front view which shows the structure of the shock absorption structure which concerns on 7th Embodiment. (A) is an expanded view which shows typically what developed the shock absorption member used for the shock absorption structure concerning an 8th embodiment along the peripheral direction, and (b) is a plane sectional view of the shock absorption member. It is. It is a rear view of the impact-absorbing member used for the impact-absorbing structure which concerns on 8th Embodiment. (A) is a plane sectional view showing composition of an impact-absorbing structure concerning an 8th embodiment, (b) is the back view, and (c) is the side sectional view. (A) is a figure which shows the partial side surface cross section of the cord-like body wound around the slit of the impact-absorbing member used for the impact-absorbing structure which concerns on 8th Embodiment, (b) is a cord-like from (a) It is a figure which shows the state which removed the body. It is side surface sectional drawing which shows the structure of the 1st modification of the impact-absorbing structure which concerns on 8th Embodiment. It is an expanded view which shows typically what developed the shock absorption member used for the 1st modification of the shock absorption structure concerning an 8th embodiment along the peripheral direction, (b) is a plane section of the shock absorption member FIG. It is a rear view of the impact-absorbing structure used for the 1st modification of the impact-absorbing member which concerns on 8th Embodiment. It is a plane sectional view showing the composition of the 1st modification of the shock absorption structure concerning an 8th embodiment, and (b) is the back view. (A) is a top view which shows the structure of the deformation | transformation form of the impact-absorbing member used for the 2nd modification of the impact-absorbing structure which concerns on 8th Embodiment, (b) is the rear view. It is a side view which shows the structure of the impact-absorbing member used for the impact-absorbing structure which concerns on 9th Embodiment. (A) is an expanded side sectional view which shows what expanded the structure of the impact-absorbing structure which concerns on 9th Embodiment, (b) is the plane sectional drawing. (A) is a front view which shows the structure of the other form of a guard fence, (b) is the top view. (A) is a plane sectional view showing composition of an impact-absorbing member used in Example 1, and (b) is a plane sectional view showing a state where a loop portion of a cord-like body is wound around the impact-absorbing member. . It is a graph which shows the relationship between the displacement of the cord-like body obtained from the conditions of Example 1, and the load loaded on a cord-like body. 4 is a graph showing the degree of opening for each slit position obtained from the conditions of Example 1. FIG. It is a graph which shows the relationship between the displacement of the cord-like body obtained from the conditions of Example 2, and the load loaded on a cord-like body.

  Hereinafter, embodiments for carrying out a shock absorbing structure for a cord-like body to which the present invention is applied will be described in detail with reference to the drawings.

  The shock absorbing structure 3 according to the present invention is used, for example, as a protective fence for preventing such falling by colliding with falling objects such as falling rocks and avalanches as shown in FIG. In addition to this, the shock absorbing structure 3 according to the present invention is used for a master rope, a master rope support or the like used for preventing a worker working at a high place from falling during temporary construction or the like.

  As shown in FIG. 1, the protective fence 1 is attached to a plurality of struts 11 erected at intervals in the lateral direction, a cord-like body 13 installed between the plurality of struts 11, and the cord-like body 13. And a net 15 made of a wire mesh or the like.

  The support | pillar 11 is comprised from H-section steel, a steel pipe, etc., for example. The cord-like body 13 is constituted by a cord-like thing such as a wire rope, for example. The cord-like body 13 is installed between the support bodies 31 such as the support pillars 11. As the support body 31, for example, in addition to the support pillars 11 shown in the figure, a master rope support, a levee, a ground, etc. Can be mentioned. In the protective fence 1, a protection surface for capturing falling objects A such as falling rocks is formed by the cord bodies 13 and the net body 15. When captured, an impact force in a direction P3 parallel to the front-rear direction P2 of the support 31 acts.

  As shown in FIGS. 2 to 4, the impact absorbing structure 3 according to the first embodiment includes an impact absorbing member 33, a slit 35, and a slit width holding portion 41.

  The impact absorbing member 33 is provided to absorb the impact force when the impact force acts on the cord-like body 13, and is attached to the support body 31 in the first embodiment. In the first embodiment, the shock absorbing member 33 is composed of a flat plate-like single plate material, but is not limited to this, and other than a single plate material such as a curved plate shape, as described below. You may be comprised from the some board | plate material and the member of various shapes. The shock absorbing member 33 is made of, for example, a metal such as a steel material or a synthetic resin. In the first embodiment, the shock absorbing member 33 is attached to the back side of the support column 11 as the support 31. In addition to this, the shock absorbing member 33 may be attached to the front surface of the support 31. In the first embodiment, the shock absorbing member 33 is attached by joining means such as welding or a bolt after its end 33e is abutted against the support 11 as the support 31.

  The slit 35 is provided in the shock absorbing member 33. The slit 35 is linearly provided in the first embodiment. The slit 35 is provided by cutting or punching a plate material.

  In the first embodiment, the slit 35 includes an inlet portion 36 in which the cords 13 are disposed on the inner side, and an energy absorbing portion 37 provided continuously from the inlet portion 36 in the slit longitudinal direction P1. . The cord-like body 13 disposed at the inlet portion 36 is supported by the shock absorbing member 33. In the first embodiment, the inlet portion 36 is provided in a hole shape that penetrates the impact absorbing member 33.

  The slit width holding unit 41 exhibits a function of holding the slit width of the slit 35. In the first embodiment, the slit width holding portion 41 is composed of a connection portion 42 that connects the upper portion 33a and the lower portion 33b with the slit 35 of the shock absorbing member 33 interposed therebetween, and the connection portion. 42 is provided on both sides of the slit 35 in the slit longitudinal direction P1 with a space therebetween.

  The energy absorbing portion 37 is formed so as to extend in a direction in which the cord 13 can move from the inlet portion 36 when an impact force acts on the cord 13, and in the first embodiment, the support 13 31 extends in the front-rear direction P2, in other words, in the direction P3 in which the impact force acts on the cord-like body 13.

  The energy absorbing portion 37 is formed with a slit width smaller than the diameter r of the cord-like body 13. Thereby, when the cord-like body 13 moves from the entrance part 36 by an impact force, it becomes possible to slide the cord-like body 13 reliably with respect to a pair of opposing slit side surfaces 35a.

  In addition, the energy absorbing portion 37 is formed in a taper shape so that the slit width is narrowed away from the slit width holding portion 41 in the slit longitudinal direction. Details of this will be described later.

  In the first embodiment, the slit 35 has a slit width toward the front side in the entry direction at a site where the cord 13 starts to enter the energy absorbing portion 37 when an impact force acts on the cord 13. It further has a guide portion 38 formed in a tapered shape so as to narrow. Details of this will be described later.

  In the first embodiment, the slit 35 further includes a slit bottom surface 35b provided on the front side in the direction in which the cord-like body 13 can move. Thereby, when the cord-like body 13 moves in the slit longitudinal direction P1, the impact force can be transmitted from the cord-like body 13 to the support body 31 while preventing the cord-like body 13 from coming out of the slit 35. It becomes possible.

  Next, the effect of the shock absorbing structure 3 according to the first embodiment will be described.

  As shown in FIG. 4A and the like, an impact force in the front-rear direction P2 of the support 31 acts on the cord-like body 13 when the fallen object A is captured by the protective surface. Thereby, the cord-like body 13 moves in the slit longitudinal direction P <b> 1 from the entrance portion 36 of the slit 35 to the energy absorbing portion 37. At this time, the cord-like body 13 slides on a pair of opposing slit side surfaces 35 a of the energy absorbing portion 37, and the impact force is absorbed by the friction between the pair of slit side surfaces 35 a and the cord-like body 13. become.

  Here, according to the shock absorbing structure 3 according to the first embodiment, it is assumed that the pair of slit side surfaces 35a of the energy absorbing portion 37 are worn by friction with the cord-like body 13 in a range over a part of the slit longitudinal direction P1. However, since the cord-like body 13 slides on the pair of slit side surfaces 35a in the remaining range that is not worn, even if the slit side surface 35a of the slit 35 is worn, it is continuously stabilized against the impact force. It is possible to exert shock absorbing performance.

  Moreover, according to the shock absorbing structure 3 according to the first embodiment, it is possible to exert excellent effects in the following points.

  5 and 6 show the displacement of the cord 13 when the cord 13 is moved in the longitudinal direction P1 of the slit in the energy absorbing portion 37 under variously changed conditions for the shape of the slit 35. FIG. It is a figure which shows the relationship between the load which is required when moving the cord-like body 13.

  In the examples of FIGS. 5 and 6, the slit width holding portion 41 is provided only on one end side in the slit longitudinal direction P1. FIG. 5A shows an example in which the slit width of the energy absorbing portion 37 is constant in the slit longitudinal direction P1, and FIG. 5B shows that the slit width narrows as the distance from the slit width holding portion 41 increases in the slit longitudinal direction P1. In this example, the energy absorbing portion 37 is formed in a tapered shape, and the guide portion 38 is not provided at a site where the cord-like body 13 starts to enter the energy absorbing portion 37. Further, FIG. 6A is an example in which a guide portion 38 is provided at a site where the cord-like body 13 starts to enter the energy absorbing portion 37, as compared to the example of FIG. 5B. FIG. 5B is an example in which a guide portion 38 is provided at a site where the cord-like body 13 starts to enter the energy absorbing portion 37 with respect to the example of FIG.

  When the present inventors examined, as shown to Fig.5 (a), when the slit width | variety of the energy absorption part 37 is constant over the slit longitudinal direction P1, as the slit width holding | maintenance part 41 is approached, the cord-like body 13 of FIG. It has been found that the movement of the cord-like body 13 stops when the movement resistance increases and the movement resistance becomes larger than the impact force. Thus, if the cord-like body 13 stops in the middle of the slit longitudinal direction P1, the impact absorbing performance cannot be exhibited over the entire slit longitudinal direction P1 of the energy absorbing portion 37, and the desired impact absorbing performance is stabilized. Will not be obtained.

  Originally, when the cord 13 passes through the energy absorbing portion 37 of the slit 35, the slit 13 is deformed so that the slit width is opened at the passage position of the cord 13 due to the reaction force from the cord 13. The slit width becomes larger than the initial slit width. The degree of opening of the slit 35 is influenced by the bending rigidity of the shock absorbing member 33 at the passage position of the cord-like body 13, and the closer to the slit longitudinal direction P1 with respect to the slit width holding portion 41, the closer to the slit. The degree of opening of the slit 35 is increased. In addition, the movement resistance of the cord-like body 13 is affected by the slit width at the energy absorbing portion 37. The movement resistance increases as the slit width decreases, and the movement resistance decreases as the slit width increases. For this reason, when the slit width of the energy absorbing portion 37 is constant in the slit longitudinal direction P1, the movement resistance is small at the position where the opening degree of the slit 35 is large at the passage position of the cord-like body 13, and the opening degree of the slit 35 is small. It is considered that the movement resistance of the cord-like body 13 increases as the distance from the slit width holding portion 41 approaches as a result.

  Further examination based on such findings reveals that the shape of the energy absorbing portion 37 of the slit 35 becomes narrower as the shape moves away from the slit width holding portion 41 in the slit longitudinal direction P1, as shown in FIG. 5B. It has been found that it is effective to have a tapered shape. Accordingly, the closer to the slit width holding portion 41, the wider the slit width, and the farther from the slit width holding portion 41, the narrower the slit width. As a result, the actual slit width at the passage position of the cord-like body 13 can be made substantially constant in the slit longitudinal direction P1, and the movement resistance of the cord-like body 13 can be suppressed from fluctuating in the slit longitudinal direction P1, As a result, it is possible to exhibit impact absorbing performance over the entire length in the slit longitudinal direction P1 of the energy absorbing portion 37.

  In addition, as shown in FIG.5 (b), when the slit width holding | maintenance part 41 is provided only in the one end side of the slit longitudinal direction P1, the energy absorption part 37 is the narrowest in the other end side of the slit longitudinal direction P1. A taper is used so that the portion 37a is provided. Further, as shown in FIG. 3 and the like, when the slit width holding portion 41 is provided with an interval in the slit longitudinal direction P1 with respect to the slit 35, the energy absorbing portion 37 is adjacent to the slit longitudinal direction P1. A slit formed so that the narrowest portion 37a is provided at a substantially central position of the slit width holding portion 41 is used. This is because the bending rigidity is the smallest in the center position in the range extending in the slit longitudinal direction P1.

  Further, as a result of the study by the present inventors, as shown in FIGS. 5 (a) and 5 (b), when there is a step at a site where the cord 13 starts to enter the energy absorbing portion 37, the cord 13 In the initial stage when the impact force is applied to the energy absorbing portion 37, the entry resistance when the cord-like body 13 enters the energy absorbing portion 37 becomes very large. As a result, the energy absorbing portion 37 is not affected unless a large impact force is applied. It has been found that the cord-like body 13 does not enter the inside and the desired shock absorbing performance is not exhibited.

  As a result of further intensive studies to solve such problems, as shown in FIG. 6 (a), the slit 35 has a shape in which the cord 13 starts to enter the energy absorbing portion 37, as shown in FIG. It has been found that it is effective to provide a guide portion 38 formed in a tapered shape so that the slit width becomes narrower toward the front side. Thereby, the approach resistance to the energy absorbing portion 37 at the initial stage when the impact force is applied to the cord-like body 13 is reduced, and a desired impact absorption performance can be exhibited even with a small impact force.

  As shown in FIG. 6B, the slit width of the energy absorbing portion 37 is made constant in the slit longitudinal direction P <b> 1, and the guide portion 38 is located at a site where the cord-like body 13 starts to enter the energy absorbing portion 37. It is good also as providing. In this case, although there is a possibility that the impact absorbing performance cannot be exhibited with the entire length in the slit longitudinal direction P1 of the energy absorbing portion 37, the desired impact absorbing performance can be exhibited even with a small impact force.

  Further, the slit side surface 35a of the energy absorbing portion 37 and the guide portion 38 of the slit 35 may be formed in a curved surface as shown in FIG. 3 and the like, or may be tapered, as shown in FIG. As shown, it may be flat and tapered.

  In addition, according to the shock absorbing structure 3 according to the first embodiment, the shock absorbing performance can be adjusted by adjusting the slit width of the energy absorbing portion 37 of the slit 35. Such adjustment of the slit width can be easily realized by using a gap gauge or the like. For this reason, according to the shock absorbing structure 3 according to the first embodiment, it is not necessary to finely adjust the tightening force with a bolt, a caulking or the like, and a desired shock absorbing performance can be easily obtained.

  Next, the shock absorbing structure 3 according to the second embodiment will be described. In addition, about the component same as the component mentioned above, the description below is abbreviate | omitted by attaching | subjecting the same code | symbol.

  In the second embodiment, the shock absorbing member 33 is composed of a plurality of plate members 34 that are spaced apart from each other as shown in FIG. The plurality of plate members 34 are attached to the support 31 after being arranged so that a slit 35 having an inlet portion 36 and an energy absorbing portion 37 is provided between them.

  In the second embodiment, the plurality of plate members 34 are arranged with their positions shifted in the axial direction of the cord-like body 13. The degree to which this position is shifted is such that the slanted cords 13 can be easily arranged between the corners 34a of the plurality of plate members 34. Further, when the cable 13 is moved by the impact force within the energy absorbing portion 37 of the slit 35, the slit side surface 35a of the upper plate member 34 and the slit side surface 35a of the lower plate member 34 are shifted. Both are set to such an extent that the cord 13 can slide.

  Moreover, in 2nd Embodiment, the support body 31 itself with which the some board | plate material 34 was attached functions as the slit width holding part 41 holding the slit width of the slit 35, and the slit width holding part 41 is a slit. It is provided only on one end side in the longitudinal direction P1. In addition, the energy absorbing portion 37 is formed in a tapered shape so that the narrowest portion 37a is provided on the opposite side of the support body 31 in the slit longitudinal direction P1. Thereby, it becomes possible to suppress that the movement resistance of the cord-like body 13 fluctuates in the slit longitudinal direction P1, and it is possible to exhibit the impact absorbing performance over the entire length of the energy absorbing part 37 in the slit longitudinal direction P1. .

  According to the impact absorbing structure 3 according to the second embodiment, since it is not necessary to perform drilling or the like on the plate material, it is easy to realize and the manufacturing cost can be reduced.

  Next, the shock absorbing structure 3 according to the third embodiment will be described.

  As shown in FIGS. 8 and 9, the impact absorbing structure 3 according to the third embodiment further includes a position holding member 51 attached to the support 31 on the side of the impact absorbing member 33. The position holding member 51 holds the position in a state in which the cord-like body 13 is slidable in the axial direction.

  The position holding member 51 is exemplified by a U-bolt, but is not limited thereto. In the position holding member 51 composed of a U-bolt, both ends 51a of the U-bolt are inserted into the column 11 as the support 31 and the nut 52 is screwed, and the cord-like body 13 is inserted into the recess 51b of the U-bolt. It is inserted. The position holding member 51 composed of the U-bolt is adjusted in the degree of screwing of the nut 52 so that the cord 13 can slide in the axial direction when an impact force is applied to the cord 13. ing.

  The position holding member 51 holds the position of the cord 13 on the front side in the direction in which the cord 13 can move from the inlet 36 of the slit 35 when an impact force is applied. In the illustrated example, two position holding members are provided on both the left and right sides of the shock absorbing member 33 so that the concave portion 51b of the position holding member 51 formed of a U-bolt and the energy absorbing portion 37 of the slit 35 are positioned substantially on the same axis. 51 is arranged. The cord-like body 13 disposed in the entrance portion 36 of the shock absorbing member 33 is held by the concave portions 51b of the two position holding members 51 on the front side in the direction in which the cord-like body 13 can move. The body 13 is arranged in a convex shape.

  According to the above third embodiment, as shown in FIG. 9B, after the cord-like body 13 moves in the slit longitudinal direction P1 by the impact force, the cord-like shape between the support bodies 31 is moved. The erection length of the body 13 can be increased. As a result, when the shock absorbing structure 3 according to the third embodiment is used as a protective fence, the inclination angle θ of the cord-like body 13 with respect to the straight line L1 parallel to the straight line passing through the adjacent support bodies 31 can be increased. It becomes possible. At this time, as the tilt angle θ increases, the longitudinal component of the support 31 of the impact force acting as a tensile force on the cord 13 increases, and the impact force from the fallen object A is more effective on the support 31. Therefore, the impact absorbing performance by the support 31 can be effectively exhibited.

  Further, when the shock absorbing structure 3 according to the third embodiment is used for the protective fence 1 including the net body 15, the following effects are exhibited. The case where the cord-like body 13 and the net | network body 15 of the same length are attached between the adjacent support bodies 31 is considered. In this case, if the cord-like body 13 and the net body 15 are displaced in the front-rear direction P2 of the support body 31, generally, the cord-like body 13 breaks earlier than the net body 15 at a stage of some displacement. There is a tendency to end up. This is because the net 15 has a larger amount of displacement in the front-rear direction P <b> 2 required to reach the maximum tension than the cord 13. Thus, if the cord-like body 13 breaks earlier, it will be difficult to sufficiently exhibit the shock absorbing performance by the mesh body 15.

  Here, if it becomes possible to lengthen the construction length of the cord-like body 13 between the support bodies 31 as in the shock absorbing structure 3 according to the third embodiment, it is necessary to reach the maximum tension. The amount of displacement in the front-rear direction P2 can be adjusted to the same extent between the cord-like body 13 and the net body 15, and as a result, the shock absorbing performance by both the cord-like body 13 and the net body 15 is sufficiently exhibited. It becomes possible.

  Next, the shock absorbing structure 3 according to the fourth embodiment will be described.

  As shown in FIG. 10, the shock absorbing structure 3 according to the fourth embodiment further includes a position holding member 51 attached to the fixed plate 32 on the side of the shock absorbing member 33. The position holding member 51 holds the position in a state in which the cord-like body 13 is slidable in the axial direction.

  In the fourth embodiment, the shock absorbing member 33 is attached to the cord-like body 13 without being joined to the support body 31 shown in FIG. 1 and is suspended and supported by the cord-like body 13. Further, the cord-like body 13 is fixed to the support body 31 shown in FIG. 1 on both sides in the axial direction with respect to the shock absorbing member 33.

  According to the shock absorbing structure 3 according to the fourth embodiment described above, the installation length of the cord-like body 13 between the support bodies 31 shown in FIG. 1 is determined by the impact force as described in the third embodiment. It becomes possible to lengthen after the movement of the cord-like body 13. Thereby, for the same reason as described in the third embodiment, it is possible to effectively exhibit the shock absorbing performance by the support 31, and the cord-like body 13 and the net 15 shown in FIG. It is possible to fully exhibit the shock absorbing performance by both.

  Further, according to the fourth embodiment, the shock absorbing member 33 can be attached not only to the end of the cord-like body 13 and the vicinity of the support 31 shown in FIG. Therefore, it can be used without being restricted by the length of the cord-like body 13.

  Next, the shock absorbing structure 3 according to the fifth embodiment will be described.

  As shown in FIG. 11, the shock absorbing structure 3 according to the fifth embodiment includes a cord-like body fixing portion provided in a hole shape penetrating the shock absorbing member 33 on the side of the slit 35 in the shock absorbing member 33. 40 is further provided. The cord-like body fixing part 40 fixes the cord-like body 13 in a state where the cord-like body 13 is sandwiched between the caulking metal fittings 16 (position holding member 51). The cord-like body fixing portion 40 is not limited to this, and the cord-like body 13 may be fixed by welding or the like.

  In the fifth embodiment, the shock absorbing member 33 is attached to the cord-like body 13 without being joined to the support body 31 shown in FIG. 1 and is suspended and supported by the cord-like body 13. Further, the cord-like body 13 is fixed to the support body 31 shown in FIG. 1 on both sides in the axial direction with respect to the shock absorbing member 33.

  The cord-like body 13 is sandwiched by the caulking metal fitting 16 (position holding member 51) or the like at the inlet 36 and fixed in the axial direction, and the installation length is increased on the front side or the rear side of the fixing plate 32. The position is held at. When the impact force is applied, the cord-like body 13 moves from the inlet portion 36 to the energy absorbing portion 37 while being sandwiched between the crimping fittings 16 (position holding member 51).

  According to the shock absorbing structure 3 according to the fifth embodiment described above, as described in the third embodiment, the installation length of the cord-like body 13 between the support bodies 31 shown in FIG. It becomes possible to lengthen after the movement of the cord-like body 13. Thereby, for the same reason as described in the third embodiment, it is possible to effectively exhibit the shock absorbing performance by the support 31, and the cord-like body 13 and the net 15 shown in FIG. It is possible to fully exhibit the shock absorbing performance by both.

  Further, according to the fifth embodiment, it is possible to attach the shock absorbing member 33 not only to the end portion of the cord-like body 13 and the vicinity of the support body 31 shown in FIG. Therefore, it can be used without being restricted by the length of the cord-like body 13.

  Next, the shock absorbing structure 3 according to the sixth embodiment will be described.

  As shown in FIGS. 12 to 16, the shock absorbing structure 3 according to the sixth embodiment includes a shock absorbing member 33 around which a loop portion 14 in which a part of the cord-like body 13 is ring-shaped is wound, and the cord-like body. A slit 35 provided in the shock absorbing member 33 along a portion around which the 13 loop portions 14 are wound, and a slit width holding portion 41 that holds the slit width of the slit 35 are provided.

  In addition, in Fig.15 (a), what expanded the impact-absorbing member 33 used for the impact-absorbing structure 3 which concerns on 6th Embodiment along the circumferential direction is shown typically, Fig.15 (a), In FIG. 15B, the alternate long and short dash lines a to d are in a positional relationship corresponding to each other.

  Since the shock absorbing member 33 is partially different from the shock absorbing member 33 described in the first to fifth embodiments, only the points different from those described in the first to fifth embodiments. Explanation will be omitted, and description of common points will be omitted.

  In the sixth embodiment, the shock absorbing member 33 is formed of a cylindrical body, but is not limited to this, and is bent by bending a plate material into a U shape, a V shape, or the like, as will be described later. It may be composed of a body, a flat plate material, or the like.

  In the sixth embodiment, the shock absorbing member 33 is attached to the cord-like body 13 without being joined to the support body 31 and is suspended and supported by the cord-like body 13.

  The slit 35 is provided in a curved shape in the sixth embodiment. In the sixth embodiment, the slit 35 is formed only in a range extending over a part of the shock absorbing member 33 in the circumferential direction. In addition to this, the slit 35 may be formed in a range over the entire circumferential direction of the shock absorbing member 33 as described later.

  In the sixth embodiment, the slit 35 includes an energy absorbing portion 37 formed with a slit width smaller than the diameter r of the cord-like body 13 and inlet portions 36 formed on both sides of the slit longitudinal direction P1 of the energy absorbing portion 37. I have. Since the energy absorbing portion 37 is formed with a slit width smaller than the diameter r of the cord-like body 13, when the cord-like body 13 moves inside due to an impact force, the energy absorbing portion 37 is opposed to a pair of opposing slit side surfaces 35a. Thus, the cord-like body 13 can be reliably slid.

  In the sixth embodiment, the slit width holding portion 41 is composed of a connecting portion 42 that connects the upper portion 33a and the lower portion 33b with the slit 35 of the shock absorbing member 33 interposed therebetween, and the connecting portion. 42 is provided on both sides of the slit 35 in the slit longitudinal direction P1.

  In the sixth embodiment, in the sixth embodiment, the intermediate portion 14 a of the loop portion 14 is wound around the energy absorbing portion 37 of the slit 35, and both end portions 14 b of the loop portion 14 are inserted into the inlet portions 36 of the slit 35. Has been. In the sixth embodiment, the end portion 14b of the loop portion 14 is inserted into each of the inlet portion 36 on one end side of the slit longitudinal direction P1 and the inlet portion 36 on the other end side in the sixth embodiment.

  The energy absorption part 37 is formed in a taper shape so that the slit width becomes narrower as it moves away from the slit width holding part 41 in the slit longitudinal direction P1. This is for the same reason as described in the first embodiment, and is intended to suppress the movement resistance of the cord-like body 13 from fluctuating in the slit longitudinal direction P1. For this purpose, in the sixth embodiment, the energy absorbing portion 37 is formed in a tapered shape so that the narrowest portion 37a is provided at a substantially central position of the slit width holding portion 41 adjacent in the slit longitudinal direction P1. Use things.

  Further, in the sixth embodiment, the slit 35 is located at a portion from the inlet portion 36 to the energy absorbing portion 37 where the cord-like body 13 begins to enter the energy absorbing portion 37 when an impact force is applied. It further has a guide portion 38 formed in a tapered shape so that the slit width becomes narrower toward the front side in the approach direction. This is for the same reason as described in the first embodiment, and aims to reduce the entry resistance at the initial stage when the impact force is applied to the cord-like body 13.

  The shock absorbing structure 3 according to the sixth embodiment includes a fixing member 65 that fixes the cord 13 to the support 31 on both sides in the axial direction of the cord 13 with respect to the shock absorbing member 33.

  Next, functions and effects of the shock absorbing structure 3 according to the sixth embodiment will be described.

  When the fallen object A is captured by the protective surface, the impact force from the fallen object A acts on the cord-like body 13 as an axial tensile force of the cord-like body 13. As a result, the loop portion 14 of the cord-like body 13 tries to be deformed so that the diameter thereof is reduced, and a part of the cord-like body 13 intersecting with the slit 35 moves the energy absorbing portion 37 of the slit 35 in the slit longitudinal direction P1. Will do. At this time, the cord-like body 13 slides on a pair of opposing slit side surfaces 35 a of the energy absorbing portion 37, and the impact force is absorbed by the friction between the pair of slit side surfaces 35 a and the cord-like body 13. become.

  According to the shock absorbing structure 3 according to the sixth embodiment described above, even if the slit side surface 35a of the slit 35 is worn for the same reason as described in the first embodiment, the shock absorbing structure 3 is continuously stable against the impact force. It is possible to exert the shock absorbing performance.

  In addition, according to the sixth embodiment, the energy absorbing portion 37 is formed in a tapered shape so that the slit width becomes narrower as the distance from the slit width holding portion 41 increases, and thus the same reason as described in the first embodiment. Thus, it is possible to suppress the movement resistance of the cord-like body 13 from fluctuating in the slit longitudinal direction P1, and it is possible to exhibit the impact absorbing performance over the entire length of the energy absorbing portion 37 in the slit longitudinal direction P1.

  Further, according to the sixth embodiment, the guide portion 38 is provided at a site where the cord 13 starts to enter the energy absorbing portion 37 when an impact force is applied. For the same reason as described above, the entry resistance when an impact force acts on the cord-like body 13 is reduced, and a desired impact absorbing performance can be exhibited even with a small impact force.

  Further, according to the sixth embodiment, as described in the third embodiment, the construction length of the cord-like body 13 between the supports 31 is increased after the cord-like body 13 is moved by the impact force. It becomes possible. Thereby, for the same reason as described in the third embodiment, it is possible to effectively exhibit the impact absorbing performance by the support 31 and the impact by both the cord 13 and the net 15. It is possible to fully exhibit the absorption performance.

  Further, according to the sixth embodiment, the shock absorbing member 33 can be attached not only to the end portion of the cord-like body 13 and the vicinity of the support body 31 but also to any part of the cord-like body 13. It can be used without being limited by the length of the body 13.

  Next, the shock absorbing structure 3 according to the seventh embodiment will be described.

  In the seventh embodiment, as shown in FIGS. 17 to 19, the shock absorbing member 33 includes a connecting member 43 attached across the upper portion 33 a and the lower portion 33 b of the shock absorbing member 33 with the slit 35 interposed therebetween. In addition. The connecting member 43 functions as a slit width holding portion 41 that exhibits the function of holding the slit width of the slit 35. In the seventh embodiment, the connecting member 43 is attached to the slit 35 at a substantially central position in the slit longitudinal direction.

  In the seventh embodiment, the connecting member 43 is inserted into the pair of plate members 44 respectively joined to the upper portion 33a and the lower portion 33b of the shock absorbing member 33, and the nut 45 is screwed together. The bolt 46 is made up of. The nut 45 is screwed to such an extent that the slit width of the slit 35 can be sufficiently maintained. The connecting member 43 is not limited to such a structure. For example, as described later, the connecting member 43 is disposed across the upper portion 33a and the lower portion 33b of the shock absorbing member 33, and the upper portion 33a and the lower portion 33b are connected to each other. You may be comprised from the board | plate material etc. which were joined to each.

  In the seventh embodiment, the energy absorbing portion 37 has a wide slit width at a position where the connecting member 43 as the slit width holding portion 41 is present, and the connecting portion 42 as the slit width holding portion 41 adjacent in the slit longitudinal direction, The narrowest portion 37a is formed at a substantially central position between the connecting member 43 and a tapered shape. As a result, it is possible to suppress the movement resistance of the cord-like body 13 from fluctuating in the slit longitudinal direction P1, and as a result, it is possible to exhibit the shock absorbing performance over the entire length of the energy absorbing portion 37 in the slit longitudinal direction P1. Become.

  When the widest slit 37b is the widest portion 37b in the energy absorbing portion 37, in the seventh embodiment, the narrowest portion 37a and the widest portion 37b are arranged in the slit longitudinal direction P1 in the energy absorbing portion 37. It will be provided alternately. Further, if the slit width w of the widest portion 37b is the slit width w, the energy absorbing portion 37 has a tapered shape such that the slit width w of the widest portion 37b is smaller than the diameter r of the cord-like body 13. You can do it.

  Next, the shock absorbing structure 3 according to the eighth embodiment will be described.

  In the eighth embodiment, the slit 35 is provided in a range over the entire circumferential direction of the shock absorbing member 33 as shown in FIGS. 20 to 24. In the eighth embodiment, the slit 35 is provided with only the energy absorbing portion 37 and is not provided with the inlet portion 36 described above.

  In the eighth embodiment, the shock absorbing member 33 has a plurality of connecting members 43 attached at intervals in the circumferential direction. In the eighth embodiment, the connecting member 43 is composed of a plate material provided with an insertion groove 47 so that the cord-like body 13 can be inserted. The insertion groove 47 of the connecting member 43 is continuous with the slit 35 of the shock absorbing member 33, and the cord-like body 13 inserted through the insertion groove 47 can move within the slit 35.

  In the eighth embodiment, the energy absorbing portion 37 has a wide slit width at a position where the connecting member 43 serving as the slit width holding portion 41 is present, and is substantially at the center of the connecting member 43 adjacent to the slit 35 in the slit longitudinal direction P1. It is formed in a tapered shape so that the narrowest portion 37a is provided at the position. As a result, it is possible to suppress the movement resistance of the cord-like body 13 from fluctuating in the slit longitudinal direction P1, and as a result, it is possible to exhibit the shock absorbing performance over the entire length of the energy absorbing portion 37 in the slit longitudinal direction P1. Become.

  In the eighth embodiment, as shown in FIG. 23, the slit 35 is an outer periphery of the shock absorbing member 33, which is a part where the cord 13 starts to enter the energy absorbing portion 37 when an impact force is applied. In the side part, it has the outer peripheral side guide part 39 formed in the taper shape so that a slit width may become narrow as it goes to the approach direction front side. Here, the front side in the entry direction corresponds to a direction from the outer peripheral side of the shock absorbing member 33 toward the inner peripheral side. As a result, the entry resistance at the initial stage when the impact force is applied to the cord-like body is reduced, and a desired impact absorption performance can be exhibited even with a small impact force.

  Further, in the example shown in FIG. 22C, an example in which the overlapping portion at the intersecting portion 14 c of the loop portion 14 of the cord-like body 13 is inserted into the insertion groove 47 of the connecting member 43 is illustrated. In this example, the insertion groove 47 is formed long in the radial direction of the shock absorbing member 33, and the intersecting portion 14 c of the cord-like body 13 is inserted in the insertion groove 47 while being shifted in the radial direction of the shock absorbing member 33. Yes. In addition, as shown in FIG. 24, the insertion groove 47 is formed long in the height direction of the shock absorbing member 33, and the intersecting portion 14 c of the cord-like body 13 in the insertion groove 47 has a height of the shock absorbing member 33. It may be inserted by shifting in the vertical direction.

  Further, as shown in FIGS. 20 to 22, the shock absorbing member 33 according to the eighth embodiment has a shock absorbing member 33 in the axial direction of the cord 13 when an impact force is applied to the cord 13. A restraining member 61 for restraining the inclination of the central axis S is attached. In the eighth embodiment, the restraining member 61 is disposed so as to sandwich two portions of the cord-like body 13 at a position away from the intersecting portion 14c of the loop portion 14 from both sides in the axial direction of the shock absorbing member 33. It is comprised from a pair of made board | plate material. Thereby, when an impact force acts on the cord-like body 13 and a rotational load as shown in the direction P4 of FIG. 22A acts on the impact absorbing member 33, the central axis S of the impact absorbing member 33 is Even if the cable-shaped body 13 is inclined with respect to the axial direction, the further inclination of the cable-shaped body 13 is constrained by contacting the restraining member 61. As a result, when an impact force is applied to the cord-like body 13, the cord-like body 13 is stably inserted into the energy absorbing portion 37 of the slit 35, and the cord-like body 13 is slid within the energy absorbing portion 37. It becomes possible to make it.

  In addition to this, as shown in FIGS. 25 to 27, the restraining member 61 is an insertion hole through which two portions of the cord-like body 13 located at a position away from the intersecting portion 14 c of the loop portion 14 are inserted. 62 may be comprised from the member which has 62. In the illustrated example, the restraining member 61 also serves as the connecting member 43.

  In addition, although the connection member 43 has illustrated what consists of a single board | plate material in 8th Embodiment, in addition to this, as shown in FIG. 28, it combines several board | plate materials, a volt | bolt, a nut, etc. It may be constituted by.

  Next, the shock absorbing structure 3 according to the ninth embodiment will be described.

  In the ninth embodiment, the shock absorbing member 33 is attached to the column 11 as the support 31 by welding or the like, as shown in FIGS. 29 and 30. The impact absorbing member 33 according to the ninth embodiment is configured as a bent body having a bent portion 33c in which an intermediate portion of a plate material is bent inward and an overhang portion 33d in which both end portions of the plate material are bent outward. The protruding portion 33d is attached to the support 31 by a joining means such as welding after contacting the support 31. The slit 35 of the shock absorbing member 33 is formed extending from the bent portion 33c toward both sides.

  Next, a preferable slit width of the energy absorbing portion 37 of the slit 35 will be described.

  As described above, in the shock absorbing structure 3 according to each embodiment, as the slit width of the energy absorbing portion 37 of the slit 35 becomes narrower, a larger shock absorbing performance is obtained, but on the other hand, the cord-like body 13 may be broken. It will be high. If the cord-like body 13 is broken, the frictional force between the slit side surface 35a of the energy absorbing portion 37 and the cord-like body 13 cannot be obtained sufficiently, and the desired impact absorbing performance cannot be obtained. For this reason, in order to continuously exhibit the impact absorbing performance against the impact force, the energy absorbing portion 37 of the slit 35 has a slit width smaller than the diameter r of the cord-like body 13, and the impact force acts. In this case, it is preferable that the energy absorbing portion 37 is formed to have a slit width that allows the cord 13 to move over a predetermined length in the slit longitudinal direction P1 without breaking. The predetermined length here is set to a length that provides sufficient shock absorption performance for the required performance. The correlation between the length and the shock absorbing performance may be obtained by experiments or the like.

  Here, for the impact absorbing performance of the energy absorbing portion 37 of the slit 35, various factors such as the plate thickness of the impact absorbing member 33 and the type of the cord-like body 13 in addition to the slit width of the energy absorbing portion 37. Has an effect. For this reason, it is difficult to quantitatively derive the slit width of the energy absorbing portion 37 in consideration of obtaining a desired shock absorbing performance stably, but as a guide, the energy absorbing portion 37 is It is preferably smaller than the diameter r of the cord-like body 13 and within a range of 50% or more of the diameter r. If it is less than 50%, there is a high possibility that the cord-like body 13 will break, and there is a possibility that the desired shock absorbing performance cannot be stably obtained.

  As mentioned above, although the example of embodiment of this invention was demonstrated in detail, all the embodiment mentioned above showed only the example of actualization in implementing this invention, and these are the technical aspects of this invention. The range should not be construed as limiting. Hereinafter, other examples of other embodiments will be described.

  As shown in FIG. 31, the guard fence 1 may have a structure in which the cord-like body 13 is spirally wound around the adjacent column 11. In the example shown in the figure, the cord-like body 13 is wound so as to intersect between adjacent struts 11, and the position of the cord-like body 13 is held with respect to the strut 11 through a position holding member 72 attached to the strut 11.

  In Example 1, as shown in FIG. 32, for the impact absorbing member 33 having substantially the same structure as that described in the eighth embodiment, the slit width of the energy absorbing portion 37 is made constant over the slit longitudinal direction. Thus, the cord-like body 13 is moved into the energy absorbing portion 37, and the load applied to the cord-like body 13 at that time and the opening degree of the slit width are measured.

  As the shock absorbing member 33, a steel material having a slit width of 11.2 mm of the energy absorbing portion 37 was used. As the cord-like body 13, a steel wire rope having a diameter of 14 mm was used. The shock absorbing member 33 was fixed so as not to move with the movement of the cord-like body 13. The cord-like body 13 was moved in the energy absorbing portion 37 by fixing one end and pulling the other end with a hydraulic jack.

  The load applied to the cord-like body 13 was measured by a load cell attached to the piston of the hydraulic jack.

  The degree of opening of the slit width was measured with a pie-type displacement meter. When the four connecting members 43 in the illustrated example are the first connecting member 43A, the second connecting member 43B, the third connecting member 43C, and the fourth connecting member 43D, the pie-type displacement meter is changed from the first connecting member 43A to the first connecting member 43A. It installed for every place which left | separated equiangularity over four connection member 43D, and each installation position was made into the position x1-position x13. Each of the first connecting member 43A to the fourth connecting member 43D corresponds to the position x1, the position x5, the position x9, and the position x13. The slit width is the position x1 to the position x13 with respect to the initial value before the cord 13 is moved into the energy absorbing portion 37 of the slit 35 and the actual value while the cord 13 is being moved. Measured with From this measurement result, the difference value between the actual value of the slit width at each of the positions x1 to x13 and the initial value was obtained, and the opening degree of the slit width was evaluated using this difference value as the opening degree of the slit width.

  As a result, by pulling the other end of the cord-like body 13, the cord-like body 13 first enters the energy absorbing portion 37 of the slit 35 from the left side (x13 side) of the position x1, and then the positions x1 to x12. And moved so as to pass through the slit 35 in order. Further, when entering the energy absorbing portion 37 of the slit 35 at the position x1, as shown in FIG. 33, the entry resistance became very large. Further, when passing through the position x1, as shown in FIG. 34, the first connecting member 43A to the fourth connecting member 43D each have a small slit opening degree at a certain position, and the first connecting member 43A to the fourth connecting member. As the distance from each of the 43Ds increased, the degree of opening of the slits increased.

  In Example 2, based on the knowledge obtained in Example 1, structural analysis is performed on the shock absorbing member 33 having substantially the same structure as that described in the eighth embodiment, as shown in FIG. The load applied to the cord-like body 13 when the cord-like body 13 is moved into 37 is determined. Here, each of a condition (hereinafter referred to as Condition 1) in which the slit width of the energy absorbing portion 37 is constant over the slit longitudinal direction and a condition in which the energy absorbing portion 37 is tapered (hereinafter referred to as Condition 2). Structural analysis was performed under the conditions. Under condition 1, the energy absorbing portion 37 was shaped so that the slit width was 11.2 mm. Under condition 2, with respect to the shape of the energy absorbing portion 37, the slit width at position x1, position x5, position x9, and position x13 is 12.8 mm, and the slit width at position x3, position x7, and position x11 is 10 mm. The taper shape was as follows. A steel wire rope having a diameter of 14 mm was used as the cord-like body 13 under any conditions.

  As a result, as described in the first embodiment, the cord-like body 13 enters the energy absorbing portion 37 of the slit 35 from the position x1, and then moves so as to pass through the slit 35 sequentially from the position x1 to x12. did. As shown in FIG. 35, under condition 1, the load applied to the cord-like body 13 is large at the position x1, the position x5, and the position x9, and the difference ΔP1 between the maximum value and the minimum value of the load is about 30 kN. On the other hand, under the condition 2, the load applied to the cord-like body 13 at the position x1, the position x5, and the position x9 is almost the same as the other positions, and the difference between the maximum value and the minimum value of the load. ΔP2 was about 10 kN. This is because the movement resistance of the cord-like body 13 fluctuates in the slit longitudinal direction P by forming the energy absorbing portion 37 in a tapered shape so that the slit width becomes narrower as it moves away from the slit width holding portion 41 in the slit longitudinal direction P. It means that you can suppress.

  In addition, the above-mentioned Examples 1 and 2 show an example of the effect in the case of the form of illustration to the last, and the content of invention is not limited to these.

1: Guard fence 3: Shock absorption structure 11: Strut 13: Cable body 14: Loop part 15: Net body 16: Caulking metal fitting 31: Support body 32: Fixing plate 33: Shock absorbing member 35: Slit 36: Entrance part 37 : Energy absorption part 37a: narrowest part 38: guide part 39: outer peripheral side guide part 40: cord-like body fixing part 41: slit width holding part

Claims (9)

An impact absorbing structure for absorbing an impact force when a fallen object collides with a cord-like body constructed between supports,
An impact absorbing member provided with a slit;
A slit width holding portion for holding the slit width of the slit,
The slit has an inlet portion in which the cord-like body is disposed inside, and an energy absorbing portion that extends in a direction in which the cord-like body can move from the inlet portion when the impact force is applied. ,
The energy absorbing portion is formed to have a slit width smaller than the diameter of the cord-like body, and is formed in a tapered shape so that the slit width becomes narrower as the distance from the slit width holding portion increases in the slit longitudinal direction. A shock-absorbing structure for cords. The slit has a guide portion formed in a taper shape so that the slit width becomes narrower toward the front side in the entry direction at a portion where the cord-like body starts to enter the energy absorbing portion when the impact force is applied. The cord-like shock absorbing structure according to claim 1, further comprising: The slit width holding portion is provided with an interval in the slit longitudinal direction with respect to the slit,
The energy absorbing portion is formed in a tapered shape so that a narrowest portion having a narrowest slit width is provided at a substantially central position of the slit width holding portions adjacent in the slit longitudinal direction. Item 3. The shock absorbing structure for cords according to Item 1 or 2. An impact absorbing structure for absorbing impact force when a fallen object collides with a cord-like body built between supports,
An impact absorbing member provided with a slit;
A slit width holding portion for holding the slit width of the slit,
The slit has an inlet portion in which the cord-like body is disposed inside, and an energy absorbing portion that extends in a direction in which the cord-like body can move from the inlet portion when the impact force is applied. ,
The energy absorbing portion is formed with a slit width smaller than the diameter of the cord-like body,
The slit has a guide portion formed in a taper shape so that the slit width becomes narrower toward the front side in the entry direction at a portion where the cord-like body starts to enter the energy absorbing portion when the impact force is applied. A cord-like shock absorbing structure characterized by further comprising: An impact absorbing structure for absorbing an impact force when a fallen object collides with a cord-like body constructed between supports,
A shock absorbing member around which a loop portion having a ring-shaped part of the cord-like body is wound;
A slit that is provided in the shock absorbing member along a portion around which the loop portion of the cord-like body is wound, and through which the cord-like body that forms the loop portion is inserted ,
A slit width holding portion for holding the slit width of the slit,
The slit has an energy absorbing portion formed in a slit width smaller than the diameter of the cord-like body,
The energy absorbing portion is formed in a taper shape so that the slit width on the side where the loop portion inserted through the slit is contracted is narrowed. The slit has a guide portion formed in a taper shape so that the slit width becomes narrower toward the front side in the entry direction at a portion where the cord-like body starts to enter the energy absorbing portion when the impact force is applied. The impact-absorbing structure for a cord-like body according to claim 5, wherein the structure has a shock-absorbing structure. The slit width holding portion is provided with an interval in the slit longitudinal direction with respect to the slit,
The energy absorbing portion is formed in a tapered shape so that a narrowest portion having a narrowest slit width is provided at a substantially central position of the slit width holding portions adjacent in the slit longitudinal direction. Item 7. The cable-shaped shock absorbing structure according to Item 5 or 6. An impact absorbing structure for absorbing an impact force when a fallen object collides with a cord-like body constructed between supports,
A shock absorbing member around which a loop portion having a ring-shaped part of the cord-like body is wound;
A slit that is provided in the shock absorbing member along a portion around which the loop portion of the cord-like body is wound, and through which the cord-like body that forms the loop portion is inserted ,
A slit width holding portion for holding the slit width of the slit,
The slit has an energy absorption part formed to have a slit width smaller than the diameter of the cord-like body, and a direction in which the cord-like body starts to enter the energy absorption part when the impact force is applied. A cord-shaped shock absorbing structure comprising a guide portion formed in a tapered shape so that the slit width becomes narrower toward the front side. A support body composed of a plurality of support columns standing at intervals in the lateral direction;
A cord-like body constructed between a plurality of supports,
The guard fence according to any one of claims 1 to 8, wherein the cord-like body uses the shock absorbing structure of the cord-like body.

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