JP5959776B1 - Ladder fall prevention device - Google Patents

Abstract

A ladder overturn prevention device that can be attached to a ladder very easily and can prevent an operator on the ladder from falling to the ground by supporting the ladder from below when the ladder falls down. I will provide a. An upper member 10 that can be placed on the upper surface of a step rail 70 of a ladder 200, a lower member 20 that covers the lower surface of the step rail 70, and the step rail 70 between the upper member 10 and the lower member 20 are provided. A connecting member 30 that connects the upper member 10 and the lower member 20 and a bar member 50 that extends downward from the lower member 20 so as to be able to go in and out, and the length of the lower member 20 in the front-rear direction. Is formed longer than the length of the upper member 10 in the front-rear direction, and the ladder 200 is supported from below by the lower member 20 and the bar member 50 when the ladder 200 falls. [Selection] Figure 5

Description

  The present invention relates to a ladder overturn prevention device. More specifically, the present invention can be attached to a ladder (including a ladder using a stepladder as a ladder. The same shall apply hereinafter), and when the ladder falls, It is related with the ladder fall prevention tool which can prevent the worker on a ladder (henceforth "worker") falling on the ground by supporting from below.

  Conventionally, as a means for preventing the ladder from toppling over, a base plate attached to a part of the ladder, a presser arm attached to the upper side of the base plate so as to be tiltable, and tiltable to the lower side of the base plate There has been known a fall prevention device for a ladder that includes a holding arm that is attached and extends in a facing manner with the presser arm (see Patent Document 1).

  In the ladder overturn prevention device described in Patent Document 1, the presser arm and the receiving arm are respectively tilted and then fixed to the base plate in contact with the upper and lower surfaces of the installation target. Thus, an installation object (for example, a protruding portion such as a roof eave) can be sandwiched from above and below by the presser arm and the receiving arm.

Japanese Patent No. 4297156

  However, the fall prevention device for a ladder described in Patent Document 1 is configured to sandwich a protruding portion (installation target) such as a roof eave from above and below by a presser arm and a receiving arm. Therefore, when such a projecting portion does not exist in the installation target in the first place (when a ladder is leaned against a wall), the ladder cannot be installed in a stable state. That is, the fall prevention device for a ladder described in Patent Document 1 can be used only when a protruding portion such as a roof eave exists on the installation target, and in a scene where the protruding portion does not exist. (The ladder cannot be stably installed in a situation where there is no projecting portion such as a roof eave or the like on the installation target).

  Further, in the ladder overturn prevention device described in Patent Document 1, when the presser arm and the receiving arm are sandwiched between projecting parts (installation objects) such as a roof eave, an operator climbs on the ladder. Since this work must be performed, if the ladder falls during this work, the safety of the worker cannot be ensured. That is, when the worker climbs the ladder and holds the presser arm and the receiving arm on the protruding portion (installation target) such as a roof eave, the ladder is not sandwiched by the installation target. Therefore, if the balance of the ladder is lost at this stage, both the ladder and the worker may fall to the ground (the safety of the worker is not ensured).

  Furthermore, in the ladder overturn prevention device described in Patent Document 1, when the overturn prevention device is mounted on the ladder, it is necessary to mount the base plate on the side wall of the ladder and tighten this with a tightening bolt or the like. Therefore, in the invention described in Patent Document 1, it takes a lot of labor and labor to attach the fall prevention device (the fall prevention device cannot be attached to the ladder very easily).

  In addition, the ladder overturn prevention device described in Patent Document 1 is composed of a base plate, a presser arm, and a receiving arm, and its structure is extremely complicated. Requires a lot of labor and cost.

  Therefore, the present invention has been made in view of the above points, and can be attached to the ladder very easily, and when the ladder falls down, the ladder is supported from below so that the worker on the ladder can ground. It is an object of the present invention to provide a ladder overturn prevention device that can prevent falling.

  The ladder overturn prevention device according to the first aspect of the present invention includes an upper member that can be placed on the upper surface of the ladder, a lower member that covers the lower surface of the ladder, and a gap between the upper member and the lower member. A connecting member that connects the upper member and the lower member, and a bar member that extends downward from the lower member, so that the crosspiece can be moved in and out, and the longitudinal direction of the lower member Is longer than the length of the upper member in the front-rear direction.

  A ladder overturn prevention device according to a second aspect of the present invention is the ladder overturn prevention device according to the first aspect of the present invention, wherein the ladder overturn prevention device is extended upward from the lower member, and between the upper member and the lower member. A drop-off prevention member is provided for preventing the step-bar from dropping off from the lower member while the step-bar can enter and exit.

  The ladder overturn prevention device according to the invention of claim 3 is the ladder overturn prevention device according to claim 1 or 2, wherein a non-slip member is provided on the lower surface of the upper member. .

  The ladder overturn prevention device according to the invention of claim 4 is the ladder overturn prevention device according to any of claims 1 to 3, wherein a buffer member is provided on the upper surface of the lower member. Features.

  The ladder overturn prevention device according to the invention of claim 5 is the ladder overturn prevention device according to any of claims 1 to 4, wherein the bar member is provided with a stopper member that can be attached to the ladder. It is characterized by being.

  The ladder overturn prevention device according to the invention of claim 6 is the ladder overturn prevention device according to any of claims 1 to 5, wherein the bar member extends downward from the center of the lower member. It is characterized by.

  The ladder overturn prevention device according to the invention of claim 7 is the ladder overturn prevention device according to any of claims 1 to 6, wherein the length of the bar member in the longitudinal direction is adjustable. And

  In the first aspect of the present invention, the upper member and the lower member are connected by the connecting member so that the ladder crosspiece can be moved in and out between the upper member and the lower member. Thus, in the present invention, by placing the upper member on the upper surface of the step pedestal, the ladder overturn prevention device according to the present invention can be attached to the ladder (reducing the work burden on the operator). Can do).

  Further, in the present invention, the upper member is placed on the upper surface of the step rail, and thus the ladder overturn prevention device is attached to the ladder. Even when there is no portion, the ladder overturn prevention tool can be attached to the ladder. Therefore, according to the present invention, it is possible to prevent a danger that occurs to the operator when the ladder falls down even in a situation where there is no protruding portion such as a roof eave or the like in the installation target.

  Further, according to the present invention, as described above, the upper member and the lower member are connected by the connecting member so that the step rail can enter and exit, and the bar member extends downward from the lower member. Since it comprises, in this invention, the said ladder fall prevention tool can be attached to a ladder in the state which floated the bottom part of the bar member from the ground (state which does not contact | abut to the ground). Thereby, in this invention, since the state by which the upper member is mounted in the upper surface of the said foot crossing can be maintained, the said ladder fall prevention tool can be attached to a ladder stably.

  This will be explained in more detail. When the ladder overturn prevention device is attached to the ladder in a state where the bottom portion of the bar member is in contact with the ground, the position (height) of the upper member is fixed (height). ) Is fixed. However, when the worker climbs on the ladder in this state, a downward force is applied to the ladder due to the weight of the operator's weight, and the stepped rail on which the upper member is placed is adjusted accordingly. As a result, the upper surface of the step rail is separated from the lower surface of the upper member whose position (height) is fixed. Therefore, when such a force is repeatedly applied to the ladder, the result is that the lower surface of the upper member and the upper surface of the step rail are repeatedly separated, so the upper member placed on the upper surface of the step rail is , There is a risk of falling off the tramway.

  On the other hand, when the ladder fall prevention tool is attached to the ladder with the bottom portion of the bar member floating from the ground, a downward force due to the weight of the operator's weight is applied to the ladder, and the upper member is placed. Even if the stepped pedestal falls down, the upper member will move up and down in accordance with the movement of the stepped pedestal, so the lower surface of the upper member and the upper surface of the stepped pedestal will be separated No, the position (height) of the upper member is always the height of the step rail on which the upper member is placed (that is, the state where the upper member is placed on the upper surface of the step rail) Is maintained). Therefore, in the present invention, it is possible to maintain the state in which the upper member is placed on the upper surface of the step pedestal by attaching the ladder overturn prevention tool to the ladder with the bottom of the bar member floating from the ground. The ladder overturn prevention device can be attached to the ladder stably.

  In this way, in the present invention, with the bottom of the bar member floating from the ground, by attaching the ladder overturn prevention device to the ladder, the ladder is stably leaned against the installation target for the operator Can be informed.

  This will be described in more detail. The ladder overturn prevention device is a ladder (an angle of about 75 ° with respect to the installation target) that is stably leaned against the installation target with the bottom of the bar member floating from the ground. If the ladder gradually falls toward the ground after the ladder fall prevention device is attached to the ladder, the step rail on which the upper member is placed is mounted. The height of the bar member gradually decreases, and the upper member moves downward in accordance therewith. Therefore, the bottom of the bar member comes into contact with the ground in accordance with this movement. That is, after the ladder overturn prevention device is attached to the ladder, the bottom part of the bar member is in contact with the ground. This means that the ladder is in an unstable state (ladder from a state where the ladder is stably leaned against the installation target). Is falling toward the ground surface, indicating that the installation object has been leaned against the installation target at an angle smaller than about 75 °. Therefore, the operator can know whether or not the ladder is stably leaned against the installation target by using the position (state) of the bottom of the bar member as a mark. By attaching the tool to the ladder in this way, it is possible to further ensure the safety of the operator.

  In the present invention, since the ladder fall prevention tool may be attached to the ladder in a state where the bottom of the bar member is floated from the ground (the bottom of the bar member needs to be brought into contact with the ground when attached to the ladder. The worker can easily and quickly attach the ladder overturn prevention tool to the ladder without worrying about the distance from the step rail on which the upper member is placed to the ground.

  In addition, in the present invention, when the ladder falls down, the bar member extending downward from the lower member contacts the ground in accordance with the fall of the ladder, and the ladder is moved from below by the lower member and the bar member. Since it becomes what is supported, if this invention is used, even when a ladder falls, it can prevent that an operator falls to the ground.

  In the present invention, since the length of the lower member in the front-rear direction is longer than the length of the upper member in the front-rear direction, the lower member is configured in this way, so that even when the ladder falls, The side member can surely support (receive) the pedestal (that is, in the present invention, when the ladder falls down, the ladder can be more reliably supported from below, so that the safety of the worker is further improved. Can be secured).

  Thus, the present invention can attach the ladder overturn prevention device to the ladder very easily and stably, and when the ladder falls down, the lower member and the bar member Thus, the ladder is surely supported from below, and therefore, by using the present invention, it is possible to provide a highly practical ladder overturn prevention device that can ensure the safety of the operator.

  In addition, the ladder overturn prevention device according to the present invention can be manufactured easily and at low cost because the overall configuration is very simple.

  According to a second aspect of the present invention, there is provided a drop-off prevention member for preventing the step rail from dropping from the lower member while the step rail can be moved in and out between the upper member and the lower member. Since it extends upward from the member, in the present invention, in addition to being able to attach the ladder overturn prevention device to the ladder very easily, when the ladder falls down, the lower member and the bar member Thus, the ladder can be reliably supported from below. That is, when the ladder falls down, the step rail is supported from below by the lower member. However, in the present invention, the fall prevention member further slides down from the lower member (drop off). The ladder can be reliably supported from below.

  According to the third aspect of the present invention, since the non-slip member is provided on the lower surface of the upper member, the upper member can be prevented from slipping off from the step rail (stablely falling down the ladder). A protective device can be attached to the ladder).

  According to the fourth aspect of the present invention, since the buffer member is provided on the upper surface of the lower member, in the present invention, it is possible to reduce the impact when the ladder falls down. That is, in the present invention, when the ladder falls, the step rail is supported from below by the lower member. However, when the present invention is used, the step rail is supported by the lower member. Since the shock can be mitigated by the buffer member, the safety of the worker can be further ensured.

  In the invention according to claim 5, since the stopper member that can be attached to the ladder is provided on the bar member, when the ladder falls down, the bar member is placed on the ground with good balance in accordance with the fall of the ladder. It can be made to contact. That is, this stopper member has a role of keeping the distance between the ladder and the bar member constant, and when the ladder falls, the stopper member prevents the bar member from separating from the ladder more than necessary and coming into contact with the ground. Therefore, in the present invention, by using this stopper member, the ladder can be stably supported from below even when the ladder falls down.

  In the invention according to claim 6, since the bar member extends downward from the center of the lower member, in the present invention, the impact applied to the lower member and the bar member when the ladder falls down, Can be balanced. Thereby, in this invention, even if a ladder falls, since damage to a lower member and a bar member can be prevented, a worker's safety can be ensured more reliably.

  According to the seventh aspect of the present invention, since the length of the bar member in the longitudinal direction is adjustable, the ladder overturn prevention device can be attached even to ladders having various heights.

It is a side view of the ladder fall prevention tool concerning Example 1 of the present invention. It is an expansion perspective view of the upper member etc. of the ladder fall prevention tool concerning Example 1 of the present invention. It is a side view showing the state which attached the ladder fall prevention tool concerning Example 1 of the present invention to a ladder (a ladder is expressed with a sectional view). It is a front view showing the state which attached the ladder fall prevention tool which concerns on Example 1 of this invention to the ladder. In the ladder fall prevention tool concerning Example 1 of the present invention, it is a side view showing the state which supports the fallen ladder from the lower part (ladder is expressed with a sectional view). It is an expansion perspective view showing the modification of the ladder fall prevention tool which concerns on Example 1 of this invention. It is an expansion perspective view showing the modification of the ladder fall prevention tool which concerns on Example 1 of this invention.

  Hereinafter, the details of the present invention will be described with reference to the drawings.

  First, the form of the ladder overturn prevention tool 100 according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

  1 is a side view of a ladder overturn prevention device according to Embodiment 1 of the present invention, and FIG. 2 is an enlarged perspective view of an upper member and the like of the ladder overturn prevention device according to Embodiment 1 of the present invention.

  As shown in FIGS. 1 and 2, the ladder overturn prevention device 100 includes an upper member 10, a lower member 20, a connection member 30, a drop-off prevention member 40, a rod member 50, and a stopper member 60. Hereinafter, each of these constituent members will be described in order.

[Upper member 10]
As shown in FIG.1 and FIG.2, the upper member 10 consists of a plate-shaped body as a whole, and is formed so that it may become a rectangular shape in planar view. Further, a non-slip member (not shown) is provided on the entire lower surface of the upper member 10. The length of the upper member 10 in the short direction (front-rear direction; arrow B direction in FIG. 1 and the like) is approximately 4 cm, the length in the longitudinal direction is approximately 10 cm, the thickness is approximately 1 cm, and the thickness of the non-slip member is approximately It is formed to 0.2 cm. The upper member 10 can be formed of, for example, iron, an aluminum alloy, fiber reinforced plastic (Fiber Reinforced Plastics), or the like. Moreover, rubber | gum or a synthetic resin can be employ | adopted for the raw material of a non-slip member, for example.

[Lower member 20]
As shown in FIG.1 and FIG.2, the lower member 20 consists of a plate-shaped body as a whole, and is formed so that it may become a rectangular shape in planar view. A buffer member 21 is provided on the entire upper surface of the lower member 20. The length of the lower member 20 in the short direction (front-rear direction; arrow B direction in FIG. 1 and the like) is approximately 8 cm (the length of the lower member 20 in the front-rear direction is longer than the length of the upper member 10 in the front-rear direction). The length in the longitudinal direction is approximately 10 cm, the thickness is approximately 2 cm, and the buffer member 21 is approximately 1 cm thick. The lower member 20 can be formed of, for example, iron, aluminum alloy, fiber reinforced plastic, or the like. For example, rubber or synthetic resin can be used as the material of the buffer member 21.

[Connecting member 30]
As shown in FIG.1 and FIG.2, the connection member 30 is formed in the rectangular shape which consists of a plate-shaped body as a whole. The length of the connecting member 30 in the short direction (vertical direction) is approximately 7 cm, the length in the longitudinal direction is approximately 10 cm, and the thickness is approximately 1 cm. The connecting member 30 can be formed of, for example, iron, aluminum alloy, fiber reinforced plastic, or the like.

[Relationship Between Upper Member 10 and Lower Member 20 and Connecting Member 30]
As shown in FIGS. 1 and 2, the connecting member 30 extends downward from the rear end of the upper member 10 and is joined to the rear end of the lower member 20. That is, the connecting member 30 is erected between the upper member 10 and the lower member 20 and connects the upper member 10 and the lower member 20. Note that the overall shape in which the upper member 10 and the lower member 20 are connected by the connecting member 30 is substantially U-shaped when viewed from the side. (That is, the connecting member 30 connects the upper member 10 and the lower member 20 so that the crosspiece 70 can enter and exit between the upper member 10 and the lower member 20). ).

[Drop-off prevention member 40]
As shown in FIG.1 and FIG.2, the drop-off prevention member 40 is formed in the rectangular shape which consists of a plate-shaped body as a whole. The drop-off prevention member 40 extends upward from the front end of the lower member 20, and prevents a later-described step rail 70 from dropping from the lower member 20. In addition, since a crosspiece 70 (described later) enters and exits between the upper member 10 and the lower member 20 via the space A, the dropout preventing member 40 does not block the space A. . The length of the drop-off prevention member 40 in the short direction (vertical direction) is approximately 3 cm, the length in the longitudinal direction is approximately 10 cm, and the thickness is approximately 2 cm. The drop-off prevention member 40 can be formed of, for example, iron, aluminum alloy, fiber reinforced plastic, or the like.

[Bar member 50]
As shown in FIG. 1, the bar member 50 is formed in a bar shape that is entirely formed of a column. The bar member 50 includes a first bar member 50 a and a second bar member 50 b, and the first bar member 50 a is inserted into the second bar member 50 b through the fixing member 51. Explaining this in detail, the diameter of the second rod member 50b is larger than the diameter of the first rod member 50a, and the inside of the upper end side is hollow (for example, from the upper end). The inside is hollow about 20 cm toward the lower end side). The lower end side of the first bar member 50a can be inserted into a hollow portion of the second bar member 50b, and each of the first bar member 50a and the second bar member 50b is inserted from the upper surface to the lower surface. Is inserted into a hollow portion of the second rod member 50b through a fixing member 51 (not shown) for insertion (not shown). That is, the lower end side of the first bar member 50a is inserted from the upper surface side of the fixing member 51 into the hollow portion of the second bar member 50b.

  The fixing member 51 is rotatably attached to the bar member 50 (the first bar member 50a and the second bar member 50b), and the lower end side of the first bar member 50a is the second bar member 50b. By rotating this in a state of being inserted into the hollow portion, both the first bar member 50a and the second bar member 50b can be tightened (for example, the lower end side of the first bar member 50a and A male screw is provided on the upper end side of the second rod member 50b, and a female screw is provided on the inner wall of the fixing member 51 so that these can be tightened. Thereby, since the lower end side of the 1st rod member 50a can maintain (fix) the state currently inserted in the hollow part of the 2nd rod member 50b, the length of the longitudinal direction of rod member 50 is adjusted. It becomes possible to do. For example, after the lower end side of the first rod member 50a is inserted into the cavity of the second rod member 50b by about 5 cm, both the first rod member 50a and the second rod member 50b are tightened by the fixing member 51. Thereby, the length of the longitudinal direction of the rod member 50 can be shortened about 5 cm.

  A bottom portion 52 is provided at the lower end of the bar member 50 for stably bringing the bar member 50 into contact with the ground. Further, a ring member 53 for attaching a stopper member 60 described later is provided in the vicinity of the center of the rod member 50 in the longitudinal direction. The bar member 50 extends downward from the center of the lower member 20.

  The first rod member 50a has a length of approximately 105 cm and an outer diameter of approximately 4 cm, and the second rod member 50b has a length of approximately 120 cm and an outer diameter of approximately 5 cm (in this case, the rod member 50 has a maximum length of approximately 220 cm and a minimum length of approximately 205 cm). The bottom 52 is formed with a height of approximately 1 cm and an outer diameter of approximately 6 cm. In addition, the 1st rod member 50a, the 2nd rod member 50b, the fixing member 51, and the ring member 53 can be formed with iron, an aluminum alloy, fiber reinforced plastics, etc., for example. Further, as the material of the bottom 52, for example, rubber or synthetic resin can be employed.

[Stopper member 60]
As shown in FIG. 1, the stopper member 60 is entirely formed in a string shape, and one end is attached to the ring member 53 of the bar member 50. An attachment member 61 is provided at the other end of the stopper member 60, and the attachment member 61 can be hooked on the ring member 53. The attachment member 61 can be a hook or a carabiner. The stopper member 60 has an overall length of approximately 50 cm, and a string or a chain can be used.

  Next, a method for using the ladder overturn prevention device 100 according to the first embodiment of the present invention will be described with reference to FIGS. In addition, below, it demonstrates in order of [the attachment method of the ladder fall prevention tool 100 to the ladder 200], and [the action of the ladder fall prevention tool 100 when the ladder 200 falls).

  FIG. 3 is a side view showing a state where the ladder overturn prevention device according to Embodiment 1 of the present invention is attached to the ladder, and FIG. 4 shows a state where the ladder overturn prevention device according to Embodiment 1 of the present invention is attached to the ladder. It is a front view to represent. FIG. 5 is a side view showing a state in which the fallen ladder is supported from below in the ladder fall prevention device according to the first embodiment of the present invention.

[How to attach the ladder overturn prevention device 100 to the ladder 200]
As shown in FIG. 3, the worker first leans the ladder 200 against the installation target 300. At this time, the operator leans the ladder 200 so as to be at an angle of about 75 ° with respect to the installation target 300 so that the ladder 200 is stably leaned on the installation target 300.

  Subsequently, the worker attaches the ladder overturn prevention tool 100 to the ladder 200 leaning against the installation target 300. The ladder overturn prevention device 100 is attached to the ladder 200 by placing the upper member 10 on the upper surface of the stepped rail 70 on the first level of the stepped foot 70 on which the operator puts his / her foot and the stopper member 60. This is done by attaching to the ladder 200. At this time, since the non-slip member (not shown) is provided on the entire lower surface of the upper member 10, the upper member 10 does not slide down from the crosspiece 70. In addition, the stopper member 60 is attached to the ladder 200 by inserting the stopper member 60 from the lower side of the step bar 70 at a position facing the stopper member 60 and passing the attachment member 61 through the upper side of the step bar 70. (The stopper member 60 is attached to the ladder 200 in a state where it hangs down toward the ground 400). In addition, when the ladder overturn prevention device 100 is attached to the ladder 200, the lower surface of the crosspiece 70 is covered with the lower member 20.

  At this time, the ladder overturn prevention device 100 is attached to the ladder 200 with the bottom 52 of the bar member 50 floating from the ground 400 (the bottom 52 may be lifted about 5 cm from the ground 400). . By doing so, it is possible to maintain the state in which the upper member 10 is placed on the upper surface of the crosspiece 70 (the ladder overturn prevention device 100 can be stably attached to the ladder 200) and the operator In addition, it is possible to notify the state in which the ladder 200 is stably leaned against the installation target 300. In addition, this allows the operator to easily and quickly attach the ladder overturn prevention device 100 to the ladder 200 without worrying about the distance from the crosspiece 70 on which the upper member 10 is placed to the ground 400. (See paragraphs [0020]-[0025]). As described above, since the length of the bar member 50 in the longitudinal direction can be adjusted (see paragraph [0047]), when the ladder overturn prevention device 100 is attached to the ladder 200, the bottom 52 of the bar member 50 is When contacting the ground 400, the length of the bar member 50 in the longitudinal direction may be adjusted so that the bottom 52 of the bar member 50 floats from the ground 400 (that is, the length of the bar member 50 in the longitudinal direction). Since the length of the ladder can be adjusted, the ladder overturn prevention device 100 can be attached even to a ladder having various heights).

  This completes the work of attaching the ladder overturn prevention device 100 to the ladder 200.

  Then, the effect | action of the ladder fall prevention tool 100 when the ladder 200 falls is demonstrated.

[Operation of the ladder overturn prevention device 100 when the ladder 200 falls down]
As shown in FIG. 5, when the bottom portions 90, 90 of the ladder 200 are shifted in the direction opposite to the installation target 300 side (the direction of arrow a in FIG. 5), the ladder 200 moves toward the ground 400 (arrow b in FIG. 5). (Direction) Falling down (or when the ladder 200 falls toward the ground 400, the bottom portions 90 and 90 of the ladder 200 are shifted in the opposite direction to the installation target 300 side).

  At this time, the crosspiece 70 on which the upper member 10 is placed moves away from the lower surface of the upper member 10 in accordance with the movement of the ladder 200 in the directions of the arrows a and b, and remains on the lower side (in the direction of the ground 400). Is pushed down and collides with the upper surface of the lower member 20 (the crosspiece 70 is received (supported) by the lower member 20). In addition, since the buffer member 21 is provided on the entire upper surface of the lower member 20, the buffer member 21 can mitigate an impact when the step rail 70 collides with the upper surface of the lower member 20. Can do.

  In addition, after the step rail 70 collides with the upper surface of the lower member 20, the step rail 70 is pulled toward the front end of the lower member 20 by the movement of the ladder 200 in the arrow a direction, and the lower member 20. The lower member 20 is expected to drop off from the front end of the lower member 20. Since the drop-off preventing member 40 extends upward from the front end of the lower member 20, even in this case, the step rail 70 is located on the lower side. It is possible to prevent the member 20 from dropping off from the front end (the crosspiece 70 collides with the dropout preventing member 40 and its movement is stopped). That is, the drop-off prevention member 40 passes through the space A, even though the step rail 70 can enter and exit between the upper member 10 and the lower member 20 (while it can enter and exit), Is prevented from falling off the lower member 20.

  When the stepped rail 70 is pushed down downward (in the direction of the ground 400) and collides with the upper surface of the lower member 20, the ladder overturn prevention device 100 follows the downward force (in the direction of the ground 400 (FIG. 5)). The bottom 52 of the bar member 50 comes into contact with the ground 400.

  At this time, the rod member 50 is pulled in the direction of the arrow a together with the stopper member 60 attached to the ladder 200 by the movement of the ladder 200 in the direction of the arrow a, and the bottom 52 does not stably contact the ground 400. Although it seems that the stopper member 60 is preliminarily attached to the ladder 200 in a state of hanging down toward the ground 400 (in a state where the ladder 200 is stably leaned against the installation target 300), The rod member 50 is not pulled more than necessary in the arrow a direction. That is, even if the stopper member 60 is pulled in the direction of the arrow a due to the movement of the ladder 200 in the direction of the arrow a, the stopper member 60 is at most horizontal to the ground 400 from the state where it hangs down toward the ground 400. Since the tensile force in the direction of the arrow a is reduced by the movement of the stopper member 60, the rod member 50 is not pulled in the direction of the arrow a more than necessary. There is no.

  Further, since the stopper member 60 is attached to the ladder 200, the ladder overturn prevention device 100 (bar member 50) is more than necessary when the ladder 200 is overturned (when the ladder 200 moves in the directions of arrows a and b). Is not shaken in the direction opposite to the arrow a direction.

  Thus, by attaching the stopper member 60 to the ladder 200, even when the ladder 200 falls, the bar member 50 can be brought into contact with the ground 400 in a well-balanced manner in accordance with the fall of the ladder 200. The ladder 200 can be supported stably from below.

  Furthermore, since the bottom portion 52 for stably bringing the bar member 50 into contact with the ground 400 is provided at the lower end of the bar member 50, the bar member 50 can be stabilized even when the ladder 200 falls. Thus, it can be brought into contact with the ground 400.

  Further, since the bar member 50 extends downward from the center of the lower member 20, an impact applied to the lower member 20 and the bar member 50 when the ladder 200 falls (the stepped bar 70 is on the lower side). (Impact when colliding with the upper surface of the member 20) can be received in a balanced manner. Thereby, even when the ladder 200 falls down, the lower member 20 and the bar member 50 can be prevented from being damaged, so that the safety of the operator can be ensured more reliably.

  Thus, the present invention can attach the ladder overturn prevention device 100 to the ladder 200 in a very simple and stable manner. When the ladder 200 falls down, the lower member 20 Since the ladder 200 is supported from below by the rod member 50 and the bar member 50, the present invention can provide a highly practical ladder overturn prevention device that can ensure the safety of the operator. It can be done.

  Moreover, in this invention, since the upper member 10 is mounted on the upper surface of the crosspiece 70, the ladder fall prevention tool 100 is attached to the ladder 200, so there is no projecting part such as a roof eave. Even when the ladder 200 is leaned against the installation object 300, the ladder overturn prevention device 100 can be attached to the ladder 200. That is, if the present invention is used, the ladder overturn prevention device 100 can be attached to the ladder 200 even when the installation target 300 does not have a protruding portion such as a roof eave. In a situation where there is no protruding portion such as an eaves, it is possible to prevent a danger that occurs to the operator when the ladder 200 falls down.

  Furthermore, the ladder overturn prevention device 100 can be manufactured easily and at low cost because the overall configuration is very simple.

[Modification of Ladder Fall Prevention Device 100 According to the Present Example]
In this embodiment, the ladder overturn prevention device 100 (the constituent members such as the upper member 10, the lower member 20, the connecting member 30, the drop-off preventing member 40, the rod member 50, and the stopper member 60) is formed with the above dimensions. However, depending on the size of the ladder to which the ladder overturn prevention device 100 is attached, it may be formed with other dimensions (larger or smaller).

  Further, in this embodiment, the drop-off prevention member 40 is extended upward from the front end of the lower member 20, but it is possible to prevent the crosspiece 70 from dropping off from the front end of the lower member 20. If possible, the drop-off prevention member 40 may extend from the front end of the lower member 20 to the rear end side (for example, extend from the front end of the lower member 20 to the rear end side by about 1 cm). etc).

  Furthermore, if it is desired to make the configuration of the ladder overturn prevention device 100 simpler, it is possible not to provide the dropout prevention member 40 itself. In this case, the ladder overturn prevention device 100 does not have means for preventing the stepped bar 70 from falling off from the front end of the lower member 20. However, if the ladder 200 falls down, Even if the crosspiece 70 falls off from the front end of the lower member 20, before that, the treadle 70 collides with the upper surface of the lower member 20, and the ladder overturn prevention device 100 (the bottom portion 52 of the rod member 50) is grounded. 400 (that is, the ladder 200 is once supported from below by the ladder overturn prevention device 100 before the step bar 70 falls off from the front end of the lower member 20). Along with 200, the worst situation of falling to the ground 400 at a stretch can be avoided. Therefore, even if comprised in this way, a worker's safety is ensured. If it is desired to prevent the crosspiece 70 from dropping from the front end of the lower member 20 without providing the drop prevention member 40 itself, the length of the lower member 20 in the front-rear direction is set to It is preferable that the length is longer than the length in the front-rear direction (for example, the length in the front-rear direction of the lower member 20 is approximately 10 cm, etc.). 20 area is secured widely).

  In addition, in the present embodiment, a non-slip member (not shown) is provided on the entire lower surface of the upper member 10, but when the upper member 10 is placed on the upper surface of the step rail 70, the upper member 10 As long as it can be prevented from slipping off from the crosspiece 70, the non-slip member can be provided only on a part of the lower surface of the upper member 10. Note that if it is desired to simplify the configuration of the ladder overturn prevention device 100, the anti-slip member itself can be omitted. Even in this case, since the upper member 10 is placed on the upper surface of the step rail 70, the upper member 10 does not slide down from the step rail 70 easily.

  In the present embodiment, the buffer member 21 is provided on the entire upper surface of the lower member 20. However, when the crosspiece 70 collides with the upper surface of the lower member 20 (when the ladder 200 falls), If the impact due to the collision can be alleviated, the buffer member 21 can be provided only on a part of the upper surface of the lower member 20. If it is desired to make the configuration of the ladder overturn prevention device 100 simpler, the buffer member 21 itself can be omitted. Even in this case, when the ladder 200 falls, the ladder 200 is supported from below by the ladder fall prevention device 100 (the lower member 20 and the bar member 50), so that the safety of the worker is sufficiently ensured. .

  In this embodiment, the entire shape in which the upper member 10 and the lower member 20 are connected by the connecting member 30 is substantially U-shaped in a side view. Can be placed on the upper surface of the door (the step rail 70 can enter and exit between the upper member 10 and the lower member 20), and when the ladder 200 falls, the lower member 20 can receive (support) the step rail 70. In this case, the overall shape can be changed to another shape (for example, the overall shape is substantially inverted C when viewed from the side).

  In this embodiment, the connecting member 30 extends downward from the rear end of the upper member 10 and is joined to the rear end of the lower member 20. If the crosspiece 70 can be moved in and out (if the space A is secured), the connecting member 30 is extended from the rear end of the upper member 10 slightly below the front end, and the lower member 20 may be joined to the front end side slightly from the rear end of the upper member 10 (for example, extending from the rear end of the upper member 10 by about 1 cm from the front end side and from the rear end of the lower member 20 to the front end side by about 1 cm. Etc.)

  Further, in this embodiment, the rod member 50 is constituted by the first rod member 50a and the second rod member 50b, and the whole is formed in a rod shape made of a column. The whole rod member 50a and the second rod member 50b) can be formed in a rod shape made of a prism. In addition, the adjustment of the length in the longitudinal direction of the rod member 50 at this time is provided with insertion holes for adjusting the length on the lower end side of the first rod member 50a and the upper end side of the second rod member 50b. The lower end side of one rod member 50a is inserted from the upper end of the second rod member 50b into the hollow portion of the second rod member 50b, and is provided in each of the first and second rod members 50a, 50b. This is done by overlapping the insertion holes for adjusting the thickness and inserting the engagement pins here (that is, by inserting the engagement pins, the first and second rod members 50a and 50b are fixed, The length in the longitudinal direction of the bar member 50 is determined according to the position of the insertion hole for adjusting the length through which the engagement pin is inserted.

  Further, in this embodiment, the length of the bar member 50 in the longitudinal direction can be adjusted. However, if it is desired to further secure the strength of the bar member 50, the bar member 50 is provided as a single piece. It can also be configured by a bar member so that the length in the longitudinal direction cannot be adjusted.

  Further, in this embodiment, the rod member 50 is extended downward from the center of the lower member 20, but for example, it can be modified as follows.

  FIG. 6 is an enlarged perspective view showing a modification of the ladder overturn prevention device according to Embodiment 1 of the present invention.

  As shown in FIG. 6, the bar member 50 (first bar member 50 a) extends downward from the rear end of the lower member 20 (position in the center in the longitudinal direction of the lower member 20). From the upper end side of 50 (first rod member 50a) to the front end of the lower member 20, a first reinforcing member 22 is provided which is entirely formed of a rectangular plate-like body. Further, the lower surface of the lower member 20 is connected to the upper end of the bar member 50 (first bar member 50a) and one end of the first reinforcing member 22, and the second member is entirely formed of a rectangular plate-like body. A reinforcing member 23 is provided. Thus, by reinforcing the bar member 50 extending downward from the lower member 20 with the first and second reinforcing members 22 and 23, the lower member 20 and the lower member 20 when the ladder 200 falls down The impact applied to the bar member 50 (impact when the stepped rail 70 collides with the upper surface of the lower member 20) can be received in a well-balanced manner, and even when the ladder 200 falls, Damage to the bar member 50 can be prevented.

  In the present embodiment, the upper member 10, the connecting member 30, and the drop-off preventing member 40 are formed to have a rectangular shape. However, for example, they can be modified as follows.

  FIG. 7 is an enlarged perspective view showing a modification of the ladder overturn prevention device according to Embodiment 1 of the present invention.

  As shown in FIG. 7, connecting members 30a and 30b (two connecting members) are extended upward from both ends (both ends on the rear end side) in the longitudinal direction of the lower member 20, respectively. Upper members 10a and 10b (two upper members) are extended in the forward direction from the upper ends of the members 30a and 30b. Further, drop-off prevention members 40a and 40b (two drop-off prevention members) are extended upward from both ends (both ends on the front end side) in the longitudinal direction of the lower member 20, respectively. Thus, since the material cost of these members can be reduced by comprising the upper member 10, the connection member 30, and the drop-off prevention member 40, the ladder overturn prevention device 100 is manufactured at a low cost. Can do.

  Further, in this embodiment, one stopper member 60 is attached to the ring member 53 of the bar member 50. However, when the ladder 200 falls, the bar member 50 is more adapted to the fall of the ladder 200. If it is desired to contact the ground 400 with a good balance, the two stopper members 60 and 60 may be attached to the ring member 53. At this time, the stopper members 60, 60 are attached to the ladder 200 by turning the stopper members 60, 60 around the left and right support members 80, 80 of the ladder 200, respectively. The attachment members 61 and 61 provided at the ends are hooked to the ring member 53 (at this time, the stopper members 60 and 60 are of course suspended from the ground 400). . By doing so, the bar member 50 is maintained in a balance in the lateral direction (longitudinal direction of the traverse 70 in FIG. 4) by the stopper members 60, 60. Therefore, even when the ladder 200 falls, 50 can be brought into contact with the ground 400 in a more balanced manner in accordance with the falling of the ladder 200.

  In this embodiment, if it is desired to make the configuration of the ladder overturn prevention device 100 simpler, the stopper member 60 itself may not be provided. Even if it does in this way, when the ladder 200 falls down, there is no change in the crosspiece 70 colliding with the upper surface of the lower member 20, and the ladder fall-preventing device 100 is moved to the lower side according to the momentum of this collision. Since the bottom portion 52 of the bar member 50 comes into contact with the ground surface 400 and supports the ladder 200 from below, the operator's safety can be sufficiently ensured.

  In the present embodiment, the ring member 53 is provided in the vicinity of the center of the rod member 50 in the longitudinal direction. However, the position where the ring member 53 is provided is appropriately changed according to the size of the ladder to which the ladder overturn prevention device 100 is attached. Of course it can be done.

  Finally, in this embodiment, the stopper member 60 is formed in a string shape. However, when it is desired to increase the strength of the ladder overturn prevention device 100, it is made of iron, aluminum alloy or fiber reinforced. It can be composed of a rod-shaped object made of plastic or the like. In this case, since the stopper member 60 cannot be attached to the ladder 200 in a state of hanging down toward the ground 400, when the ladder 200 falls down, the bar member 50 moves in the direction of arrow a of the ladder 200. The movement causes the stopper member 60 to be pulled in the direction of arrow a. For this reason, when the ladder 200 falls, the bar member 50 does not become substantially perpendicular to the ground 400, so that the bottom 52 does not stably abut against the ground 400 (the ladder 200 is removed). Cannot be supported stably from below).

  Therefore, in the case where the stopper member 60 is constituted by the rod-shaped object, the rod member 50 is taken into account when the ladder 200 falls over in consideration of the movement (movement in the direction of arrow a) when the ladder 200 falls. It is necessary to attach the ladder overturn prevention device 100 to the ladder 200 in such a manner that it is inclined in advance toward the installation target 300 from the upper member 10 to the bottom portion 52 so that it is substantially perpendicular to the ground 400. (The stopper member 60 is attached to the ladder 200 so as to maintain this state). By doing so, even if the ladder 200 falls down and the bar member 50 is pulled in the arrow a direction together with the stopper member 60 by the movement of the ladder 200 in the arrow a direction, Thus, from the upper member 10 to the bottom 52, the state inclined toward the installation object 300 is returned to the state substantially perpendicular to the ground 400, so that the bottom 52 stably contacts the ground 400. (The ladder 200 can be stably supported from below).

  The stopper member 60 is rotatably provided in the vicinity of the center of the rod member 50 in the longitudinal direction. In addition, the stopper member 60 is attached to the ladder 200 at this time by placing the front end side of the stopper member 60 on the top surface of the stepping rail 70 and using a clamping piece provided on the front end side of the stopper member 60. Any known attachment means such as sandwiching the crosspiece 70 from the front and rear can be used.

  As described above, some modifications to the present embodiment have been described so far, but it is needless to say that these modifications can be applied in appropriate combination.

  Thus, it goes without saying that various modifications can be made in the present embodiment without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 10 Upper member 20 Lower member 21 Buffer member 22 1st reinforcement member 23 2nd reinforcement member 30 Connection member 40 Drop-off prevention member 50 Rod member 50a 1st rod member 50b 2nd rod member 51 Fixing member 52 Bottom 53 Ring member 60 Stopper member 61 Mounting member 70 Step bar 80 Prop member 90 Bottom 100 Ladder overturn prevention tool 200 Ladder 300 Installation target 400 Ground A Space B Front-back direction

Claims (7)

An upper member that can be placed on the upper surface of the ladder crossing;
A lower member that covers the lower surface of the crosspiece;
A connecting member that connects the upper member and the lower member so that the crosspiece can enter and exit between the upper member and the lower member;
A bar member extending downward from the lower member,
A ladder overturn prevention tool, wherein the length of the lower member in the front-rear direction is longer than the length of the upper member in the front-rear direction. A drop-off preventing member that extends upward from the lower member and prevents the step bar from falling off the lower member while allowing the step bar to enter and exit between the upper member and the lower member. The ladder overturn prevention tool according to claim 1, further comprising:   The ladder overturn prevention tool according to claim 1 or 2, wherein a non-slip member is provided on a lower surface of the upper member.   The ladder overturn prevention tool according to any one of claims 1 to 3, wherein a buffer member is provided on an upper surface of the lower member.   The ladder overturn prevention tool according to any one of claims 1 to 4, wherein the bar member is provided with a stopper member that can be attached to the ladder.   The ladder overturn prevention tool according to any one of claims 1 to 5, wherein the bar member extends downward from the center of the lower member. The ladder overturn prevention tool according to any one of claims 1 to 6, wherein the length of the bar member in the longitudinal direction is adjustable.

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