JP2020044157A - Winding device for safety belt and fall stop device using the same - Google Patents

Abstract

To provide a winding device that is superior in assembling properties, and is capable of suppressing a feeding amount of a strap in an emergency, and provide a compact fall stop device using the same.SOLUTION: A winding device for a safety belt is provided in which a strap 1 is biased in the winding direction so as to be drawn at any time, and the feeding of the strap 1 is prevented by a locking mechanism in an emergency. A spool 11 for winding up the strap 1 has fitting parts 11c protruding on the outside of a flange 11b of both end sides of a winding body 11a. The fitting parts 11c of both end sides are fitted into fitting holes 12a of a base 12 along the outer face of the flange 11b, respectively, and are held rotatably. A strap pin 13 where a terminal of the strap 1 is fixed is held in the inside of the spool 11, however may not become a rotational support shaft of the spool 11. The strap 1 is to be wound in an outer circumference of the winding body 11a through the inside of the spool 11.SELECTED DRAWING: Figure 2

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a winder for a strap for a safety belt worn by an operator at the time of working at a high place, and a fall prevention device using the same.

  A safety belt worn by a worker who works at a high place such as a construction site may be provided with a winder that winds a lanyard strap. This winder is urged in the winding direction so that the strap does not feel bothersome during the work, and can be unwound at any time.When the worker falls from a high place and the strap is rapidly unwound, the strap is retracted. The feeding is prevented by the lock mechanism, and the fall of the worker is restrained.

  As such a winder, for example, as described in Patent Document 1 below, a terminal of a strap is locked to a main shaft, and a bobbin for winding the strap is sandwiched between opposed plates of a frame. What is rotatably supported by the main shaft is generally used. The main shaft is required to have a large strength that can withstand the impact of a worker falling, and is made of steel, and is supported via a bearing on the frame side so that the bobbin rotates smoothly.

JP 2010-240325 A

  However, the conventional winder as described above has a complicated structure, requiring labor and cost for manufacturing and assembling parts, and in the event of an emergency when a worker falls, if the parts are damaged, the straps may become longer. It may be extended, and the fall distance of the worker may be increased.

  In addition, when combined with a shock absorber that reduces the impact received by the worker when the fall is stopped, the worker may feel bulky and troublesome.

  Therefore, an object of the present invention is to provide a winder which is excellent in assemblability and can slightly suppress the amount of feeding of a strap in an emergency, and to provide a compact fall stopping device using the same.

In order to solve the above-mentioned problems, the present invention is provided on a safety belt worn by a worker who works at a high place, and the wound strap is urged in a winding direction so that the strap can be pulled out at any time, so that the strap can be quickly moved in an emergency. In the safety band winder in which the feeding of the strap is prevented by the lock mechanism,
The spool for winding the strap has a fitting portion protruding from an outer surface of a flange at both ends of the winding drum portion, and fitting portions at both ends are fitted into fitting holes of a base along the outer surface of the flange. And held rotatably,
The strap pin to which the end of the strap is fastened is held inside the spool, but does not become a rotation support shaft of the spool,
The strap is wound around the outer periphery of the winding drum section from the strap pin via the inside of the spool.

  Further, the spool is held in the thrust direction by being fastened with the pair of bases being maintained at an interval.

Further, the pawl of the lock mechanism is provided on an end surface of the spool, and has a plurality of claws that mesh with teeth formed around the fitting hole of the base with the swing,
A web-like portion is provided between the adjacent pawls of the pawl, and the web-like portion is engaged with the teeth of the base and has a portion facing the outer surface of the flange of the spool and the teeth of the base. The pawl is sandwiched between the pawl and the inner surface to prevent relative displacement of the pawl with respect to the base in the width direction.

  Further, the hardness of the fitting portion of the spool is lower than that of the teeth of the base, and when the pull-out load of the strap is further increased in a state where the pawl of the pawl is meshed with the teeth of the base, the pawl and the pawl are in contact with each other. The tooth of the base located on the opposite side cuts into the fitting portion of the spool.

  Further, two spools are arranged in parallel, each spool is rotatably held by the base, and these are integrated.

  In addition, the winder and the shock absorber for reducing the impact by the torsion bar are arranged in series, and a fall restraint device in which these are integrated by the base is provided.

  In the crash stop device, the winder has two spools arranged in parallel, and the winder and the shock absorber are integrated by the base. .

  In the safety band winder according to the present invention, the spool is rotatably held by the base, and the strap pin to which the end of the strap is locked is held only inside the spool to prevent the strap from coming off the spool. However, since the shaft does not serve as the rotation support shaft of the spool, the strength for supporting the spool is not required, the bearing for the strap pin is not required, and the assembly process can be streamlined.

  The shock load acting on the lock mechanism in an emergency when the worker falls from a high place is received by the spool and the base, so that parts such as fine bearings are not damaged, and there is no risk of damaging the strap. The feeding amount of the strap can be slightly suppressed.

  In addition, by combining this winder with a shock absorber that alleviates the impact with a torsion bar, it is possible to construct a compact crash stop device that has a stable load characteristic that is not affected by the use environment etc. it can.

Exploded perspective view of a first embodiment of a safety band winder according to the present invention. Perspective view showing the assembled state with the case on one side opened. Cross-sectional plan view in the middle part in the thickness direction Longitudinal side view with the case closed Exploded perspective view showing the relationship between the spool, base and pawl same as above. Enlarged vertical sectional side view showing the same assembled state. (7A) Schematic plan view showing a normal state where the extension of the strap is not locked, (7B) Schematic plan view showing a locked state, and (7C) a state where teeth of the base are cut into the spool. Schematic plan view The perspective view which shows the assembled state which opened the case of one side of 2nd Embodiment of the winder for safety belts concerning this invention. 1 is a perspective view showing an assembled state in which a case on one side is opened in a first embodiment of a safety device for a fall of a safety belt in which a winder and a shock absorber according to the present invention are integrated. Cross-sectional plan view in the middle part in the thickness direction Longitudinal side view with the case closed FIG. 3 is a perspective view showing an assembled state of the second embodiment of the safety device for preventing a fall of a safety belt according to the second embodiment with one case opened.

  First, a first embodiment of a winder will be described with reference to FIGS.

  As shown in FIGS. 1 to 4, the winder includes a spool 11 in which components are housed in a pair of cases 41 and winds the strap 1, and two plate-shaped bases that sandwich the spool 11. 12 is a main part for ensuring structural strength and dimensional accuracy, and the end of the strap 1 is folded back and sewn, and is fixed to the strap pin 13.

  A pawl 14, a coil spring 15a, a bush 15b, and a cover 15c, which constitute a lock mechanism, are provided on one (upper in FIG. 1) base 12, and on the other (lower in FIG. 1) base 12, A plate 16, a bush 17 and a spiral spring 18 are provided.

  The spool 11 is an integrally molded product formed by die-casting of an aluminum alloy, a zinc alloy, or the like. As shown in FIG. 5, the spool 11 has flanges 11b on both ends of a winding drum 11a around which the strap 1 is wound. Each of the flanges 11b has a shape in which a fitting portion 11c protrudes from an outer surface thereof. The outer periphery of the fitting portion 11c is a cylindrical surface having a smaller diameter than the flange 11b.

  A groove-shaped through hole 11d penetrating in the radial direction is formed in the winding drum portion 11a, and the width of the through hole 11d is such that the width of the entrance portion at one end is slightly larger than the diameter of the strap pin 13 and the width of the one end is The diameter is set smaller than the diameter of the strap pin 13 from the entrance to the other end.

  The strap 1 is inserted into the inside of the spool 11 from one end to the other end of the inside through hole 11d, and the terminal fixed to the strap pin 13 is locked at the entrance of one end of the inside through hole 11d, The strap 1 which is prevented from falling to the other end side of the through hole 11d and pulled out from the other end of the through hole 11d is wound around the outer periphery of the winding drum portion 11a.

  The fitting portion 11c has a core shaft portion 11e protruding at the center, and a short cylindrical pawl shaft portion 11f protruding from the middle in the radial direction. A part of the fitting portion 11c is cut out to form a step 11g of a convex curved surface from the center side to the outer peripheral side.

  The base 12 is made of steel harder than the spool 11, and has a fitting hole 12a into which the fitting portion 11c of the spool 11 is fitted. Teeth 12b inclined to one side are formed on the entire periphery of the fitting hole 12a of one base 12 and a part of the periphery of the other base 12. The inside diameter of the fitting hole 12a connecting the tips of the teeth 12b is smaller than the outside diameter of the flange 11b of the spool 11, and is slightly larger than the outside diameter around the fitting portion 11c.

  As shown in FIGS. 5 and 6, the pawl 14 has a plurality (three in the illustrated example) of claws 14 a meshing with the teeth 12 b of the base 12 on the distal end side, and between the adjacent claws 14 a. A web-like portion 14b is provided so as to connect a portion closer to the spool 11. A shaft hole 14c is provided in an intermediate portion of the pawl 14, and a step 14d having a concave curved surface corresponding to the step 11g of the spool 11 is formed between the shaft hole 14c of the pawl 14 and the claw 14a.

  The pawl shaft 11f of the spool 11 is inserted into the shaft hole 14c of the pawl 14, and the pawl 14 is swingably supported. The pawl 14 is pressed by a coil spring 15a on the opposite side to the distal end side having the claw 14a across the shaft hole 14c, and the distal end side is urged in a direction to protrude from the outer periphery of the fitting portion 11c of the spool 11.

  The bush 15b is inserted into the round hole of the pawl shaft 11f of the spool 11, the cover 15c is put on the outer surface side of the pawl 14, and the screw 22a is screwed into the hole of the pawl shaft 11f. 11 is attached. As shown in FIGS. 1 and 2, the cover 15c is fixed to the fitting portion 11c of the spool 11 by two screws 22b in addition to the screw 22a.

  As shown in FIGS. 5 and 6, the web-like portion 14 b of the pawl 14, when engaged with the teeth 12 b of the base 12, faces the outer surface of the flange 11 b of the spool 11 and the teeth 12 b of the base 12. To prevent the pawl 14 from being relatively displaced from the base 12 in the thickness direction. This prevents the pawl 14 from deviating from the teeth 12b of the base 12 without increasing the thickness of the pawl 14a of the pawl 14.

  Also, as shown in FIGS. 1 to 4, on one side of the strap 1 between the two bases 12 from which the strap 1 is pulled out, two guide rollers 19a for sandwiching and guiding the strap 1 from both sides are provided with a rotating shaft 19b. And is rotatably held. Both ends of the rotating shaft 19b are inserted into the round holes of the two bases 12, respectively.

  The four corners of the two bases 12 are fastened by bolts 20a inserted into holes of one base 12 and screwed into screw holes of the other base, and sandwiched by a cylindrical spacer 20b through which the bolts 20a are inserted. The distance between the two bases 12 is maintained. Thus, the spool 11 is sandwiched between the two bases 12 and held in the thrust direction.

  On the other side of the two bases 12, a connection pin 21 for locking the belt 2 and a metal fitting to a shock absorber or the like is attached. Both ends of the connection pin 21 are inserted into holes near the other edges of the two bases 12.

  On the inner bottom surface of one (lower in FIGS. 1 and 4) case 41, a winding mechanism holding portion 41a surrounded by a circular peripheral wall is provided, and the spiral spring 18 is housed in the winding mechanism holding portion 41a. I have. A bush 17 is engaged with the center end of the spiral spring 18, the bush 17 is fitted into a hole in the center of the plate 16 covered by the spiral spring 18, and the core shaft portion 11 e of the spool 11 is fitted to the bush 17. Is inserted and locked, and the spool 11 is urged in a direction to wind up the strap 1.

  Then, one case 41 is covered with the other case 41 (upper in FIGS. 1 and 4) so as to store the components assembled in this manner, and the cases 41 are connected to each other at four corners thereof. The screw 23 inserted into the hole of the case 41 is screwed into the screw hole of the other case 41 for coupling, and the winder is in an assembled state.

  In this take-up device, the pawl 14a of the pawl 14 usually enters inside the outer periphery of the fitting portion 11c of the spool 11, as shown in FIG. 7 (7A). In this state, since the spool 11 freely rotates with respect to the base 12, the strap 1 can be pulled out from the spool 11 at any time while being urged in the winding direction.

  Then, as shown in FIG. 7 (7B), when the worker falls from a high place and the strap 1 is rapidly drawn out and the spool 11 rotates at a high speed, the tip side of the pawl 14 is brought into contact with the fitting portion 11c by centrifugal force. Projecting outward from the outer periphery of the base 11, the pawls 14 a mesh with the teeth 12 b of the base 12, and a lock state in which the extension of the strap 1 from the spool 11 is prevented.

  At this time, since the hardness of the fitting portion 11c of the spool 11 is lower than the hardness of the teeth 12b of the base 12, the pawl 14a of the pawl 14 meshes with the teeth 12b of the base 12 as shown in FIG. The teeth 12 b of the base 12 located on the side opposite to the pawl 14 bite into the fitting portion 11 c of the spool 11.

  Accordingly, the impact of the drop of the worker is received not only at the meshing portion between the pawl 14a of the pawl 14 and the teeth 12b of the base 12, but also at the portion where the teeth 12b of the base 12 bite into the fitting portion 11c of the spool 11. Therefore, the pawl 14 of the pawl 14 is prevented from being damaged.

  Further, since the impact acting on the pawl 14 is received not only at the pawl shaft portion 11f of the spool 11, but also at the contact surfaces of the steps 11g and 14d, damage around the shaft hole 14c of the pawl 14 is also prevented.

  In the safety band winder as described above, the spool 11 for winding the strap 1 is an integrally molded product by die casting, is rotatably held by the two bases 12, and the terminal of the strap 1 is locked. The strap pin 13 is held only inside the spool 11 in order to prevent the strap 1 from coming off from the spool 11, and does not serve as a rotation support shaft of the spool 11. In addition, the bearing of the strap pin 13 is not required, and the assembling process can be streamlined.

  The impact load acting on the locking mechanism in an emergency when the worker falls from a high place is received by the spool 11 and the two bases 12, so that fine parts such as bearings are not damaged, and the strap 1 may be damaged. Therefore, the amount of the strap 1 to be extended in an emergency can be slightly suppressed.

  Note that, as in the second embodiment shown in FIG. 8, two spools 11 may be arranged in parallel inside the case 41, and these may be integrated by the base 12.

  With such a parallel configuration, when the worker moves a long distance, before removing the hook at the tip of the strap 1 pulled out from one spool 11 from the structure, the strap 1 pulled out from the other spool 11 is removed. The operator hooks the hook at the end of the structure at a position away from the structure in the direction in which the structure moves, and then removes the hook at the end of the strap 1 on one of the spools 11 from the structure. An unconnected state can be prevented from occurring, and a crash accident of the worker can be prevented.

  As shown in FIGS. 9 to 11, the winder described in the first embodiment and a shock absorber for reducing the impact by the torsion bar 30 are arranged in series, and these are integrated by the base 12. It is also possible to configure a fall stop device.

  In the shock absorber according to the first embodiment of the fall stopping device, one (the lower in FIGS. 9 and 11) locking end portion 30b of the torsion bar 30 rotates around one end of the spool 31 around which the belt 3 is wound. The other end (upper in FIGS. 9 and 11) of the torsion bar 30 is engaged with one of the bases 12 holding the spool 31 from both ends. The end of the belt 3 is locked to the spool 31 by the belt pin 32. In an emergency, the shaft portion 30a of the torsion bar 30 is twisted by the pull-out of the belt 3 from the spool 31 in an emergency. Is alleviated.

  Such a fall-stopping device can share parts for the wind-up device and the shock absorber, so it has a compact and easy-to-handle size while having each function. It has a stable load characteristic that is not affected by the use environment such as aging due to long-term use.

  In addition, as in the second embodiment of the fall restraint device shown in FIG. 12, the winder has two spools 11 arranged in parallel, as in the case shown in FIG. The absorber and the base 12 may be integrated into the case 41 and housed in the case 41 so as to improve the safety when the worker moves a long distance while reducing the size.

DESCRIPTION OF SYMBOLS 1 Strap 2, 3 Belt 11 Spool 11a Roller part 11b Flange 11c Fitting part 11d Intermediate hole 11e Core shaft part 11f Paul shaft part 11g Step 12 Base 12a Fitting hole 12b Teeth 13 Strap pin 14 Paul 14a Claw 14b Shaped portion 14c Shaft hole 14d Step 15a Coil spring 15b Bush 15c Cover 16 Plate 17 Bush 18 Spiral spring 19a Guide roller 19b Rotary shaft 20a Bolt 20b Spacer 21 Connection pins 22a, 22b Screw 23 Screw 30 Torsion bar 30a Shaft 30b Lock End 31 Spool 32 Belt pin 41 Case 41a Winding mechanism holding section

Claims (7)

Provided in a safety belt worn by workers who work at heights, the wound strap (1) is urged in the winding direction so that it can be pulled out at any time, and when the strap (1) is rapidly extended in an emergency, In the safety band winder in which the feeding of the strap (1) is prevented by the lock mechanism,
The spool (11) for winding the strap (1) has fitting portions (11c) protruding from the outer surfaces of the flanges (11b) on both ends of the winding drum portion (11a), and the fitting portions on both ends thereof. (11c) is fitted into the fitting hole (12a) of the base (12) along the outer surface of the flange (11b), and is rotatably held;
The strap pin (13) to which the end of the strap (1) is fixed is held inside the spool (11), but does not become a rotation support shaft of the spool (11),
The winder for a safety band, wherein the strap (1) is wound around the outer periphery of the winding drum section (11a) from the strap pin (13) through the inside of the spool (11).   The winder for a safety belt according to claim 1, wherein the spool (11) is held in a thrust direction by fastening the pair of bases (12) while maintaining a gap therebetween. . The pawl (14) of the lock mechanism is provided on an end face of the spool (11), and meshes with a tooth (12b) formed around a fitting hole (12a) of the base (12) with the swing. It has a plurality of claws (14a),
A web-like portion (14b) is provided between the adjacent claws (14a) of the pawl (14), and the web-like portion (14b) meshes with the teeth (12b) of the base (12). In this state, the pawl (14) with respect to the base (12) is sandwiched between an outer surface of a flange (11b) of the spool (11) and an inner surface of a portion of the base (12) facing the teeth (12b). The safety band winder according to claim 1 or 2, wherein relative displacement in the width direction is prevented.   The hardness of the fitting portion (11c) of the spool (11) is lower than that of the teeth (12b) of the base (12), and the pawls (14a) of the pawl (14) are fixed to the teeth of the base (12). When the pull-out load of the strap (1) further increases in a state in which the spool (1b) is engaged with the spool (11), the teeth (12b) of the base (12) located on the opposite side to the pawl (14) become the spool (11). The safety belt winder according to any one of claims 1 to 3, wherein the safety belt winds into the fitting portion (11c).   5. The spool according to claim 1, wherein two spools (11) are arranged in parallel, each spool (11) is rotatably held by the base (12), and these are integrated. The winder for a safety belt according to any one of the above.   The winder according to any one of claims 1 to 4, and a shock absorber for reducing an impact by a torsion bar (30) are arranged in series, and these are integrated by the base (12). Features a fall prevention device for safety belts.   7. The fall prevention device for a safety belt according to claim 6, wherein the winder has two spools (11) arranged in parallel, and the winder and the shock absorber are connected to the base (12). ), A fall prevention device for a safety belt, characterized by being integrated by the above method.

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