Lever type hoisting device

Abstract

Provided is a lever type hoisting device capable of safely operating a knob at a position separated from a lever, and suppressing rattling thereof.　A base part 12 is threadedly engaged with a screw part 6a on a peripheral surface of a driving shaft 6, which is integrally constituted with a hoisting drum 4 in a body 2. A lever 10 for normal operation and a knob 14 for operation during idle rotation are connected to the base part 12. An abutting plate 26 is formed at the lower end of the screw part 6a. A ratchet wheel 8 for regulating rotation in a hoisting-down direction with respect to the body 2 is disposed between the base part 12 and the abutting plate 26 to constitute a brake. A spacer 18 is interposed between the knob 14 and the base part 12. The spacer 18 is connected to the knob 14 and the base part 12 by means of a connection structure that fits in an axial direction. A base part restriction part 20 that stops rotation of the connection structure of the spacer 18 to regulate rotation of the base part 12 is fixed to the drive shaft 6. The base part regulation part 20 is provided for preventing excessive loosening during idle rotation.

Description

Lever-type hoisting device

[0001] The present invention relates to a lever-type hoisting device equipped with a mechanical brake that automatically locks rotation in the lowering direction during hoisting operation and allows free operation in the lowering direction by turning an unlocking knob.

[0002] Conventionally, relatively small manual hoisting devices have been widely used. These hoisting devices often use a lever as the member for manual input. A reciprocating motion system using a ratchet mechanism is known as a configuration in which winding is performed by manual lever operation. In contrast to this, a mechanism employing a continuous rotation system is also known. In both these reciprocating motion system and continuous rotation system configurations, a mechanism that prevents lowering is provided as a safety device to prevent reverse rotation.

[0003] Figure 9 shows a cross-sectional view of a conventional lever-type hoisting and traction device equipped with a mechanism for preventing unwinding. The lever-type hoisting and traction device 100 is equipped with a lever 103 for normal hoisting operation and a knob 104 for rapid rotation used during free rotation. The lever 103 and knob 104 are connected to a driving member 102 that transmits driving force to a driving shaft 101. By sliding the knob 104 outward in the axial direction of the driving shaft 101, the mechanical brake can be released and rapid rotation can be performed.

[0004] Such a lever-type hoisting and traction device is described in Patent Document 1.

[0005] Japanese Unexamined Patent Publication No. 58-207299

[0006] In the lever-type hoisting and pulling device 100 shown in Figure 9 described above, when the knob (handle for quick turning) 104 is slid outward in the axial direction of the drive shaft 101, free rotation is possible, thereby improving work efficiency.

[0007] However, when the knob 104 is switched to the free-spinning state, the brake is released, and a rotational force is transmitted from the drum side to the drive shaft 101 due to the weight of the object to be hoisted, which may cause the lever 103 to swing with force. In such a case, the rotating lever 103 may hit the operator, which is dangerous. Furthermore, if the lever 103 rotates accidentally while the operator has his or her hand on the knob 104, there is a risk that the operator's fingers may be pinched between the lever 103 and the knob 104.

[0008] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a lever-type hoisting device that allows the knob to be safely operated at a position separated from the lever and that can suppress rattle.

[0009] In order to achieve the above object, the lever-type hoisting device of the present invention is characterized by comprising: a ratchet wheel rotatably attached to a drive shaft that drives a hoist drum inside a main body, and whose rotation toward the unwinding side can be switched between restricted and released on the main body side; a base that is threaded onto a screw formed on the circumferential surface of the drive shaft and that threads forward so as to clamp and fix the ratchet wheel between a structure that can move integrally with the drive shaft by rotating the connected lever toward the winding side; a knob that is formed with a smaller diameter than the lever in a radial direction centered on the drive shaft and can rotate the base; a spacer that is interposed between the base and the knob and forms a connecting structure consisting of a fitting shaft and a fitting hole that are fitted to the base and the knob, respectively, in the axial direction of the drive shaft; and a base restricting part that is fixed to the drive shaft and restricts the base from rotating in a direction away from the ratchet wheel by stopping the fitting shaft.

[0010] Furthermore, in addition to the above configuration, the lever-type hoisting device of the present invention is characterized in that the base regulating portion is a plate-like member formed with a structure that prevents the engagement shaft from rotating around the drive shaft.

[0011] In addition to the above configuration, the lever-type hoisting device of the present invention is characterized in that the mating shaft in the connecting structure on the base side and the mating shaft in the connecting structure on the knob side are arranged 90 degrees apart in the circumferential direction around the drive shaft.

[0012] As described above, according to the present invention, by rotating the base with the knob, the ratchet wheel that is clamped and fixed between the base and the structure that can move integrally with the drive shaft can be released. The base that screws in a direction away from the ratchet wheel is restricted in movement before it is threaded onto the knob because the mating shaft that is connected to and rotates integrally with the base is stopped by the base restricting portion.

[0013] Furthermore, according to the present invention, in addition to the above-mentioned effects, the rotation of the fitting shaft can be restricted by a plate-shaped member, and by restricting the rotation within a narrow range on the base side of the fitting shaft, it is possible to reduce the effect on the bending stress of the fitting shaft.

[0014] Furthermore, according to the present invention, in addition to the above configuration, the coupling shafts in the coupling structure configured on both sides via the spacer are arranged 90 degrees apart in the circumferential direction around the drive shaft, so that the effects of distortion occurring at the base of the coupling shaft can be offset on both sides, thereby preventing deformation of the spacer.

[0015] FIG. 1 is an overall perspective view showing a cross section of the lever-type hoisting device of the present invention, with a part broken away. FIG. 2 is a perspective view showing the exploded state of FIG. 1. FIG. 3 is a cross section showing the operation of the lever-type hoisting device in the hoisting state. FIG. 4 shows the lever-type hoisting device in the hoisting operation state, with (a) being a cross section showing the state in which the base is not fastened to the drive shaft, and (b) being a partially enlarged view of the state in (a). FIG. 5 shows the lever-type hoisting device in the hoisting operation state, with (a) being a cross section showing the state in which the base is fastened to the drive shaft, and (b) being a partially enlarged view of the state in (a). FIG. 6 is a perspective view of the knob as seen from the bottom side. FIG. 7 shows a spacer, with (a) being a partially enlarged view of the fitting shaft as seen from the front, and (b) being an overall perspective view. FIG. 8 is a schematic view showing modified versions of the lever-type hoisting device of FIG. 1, with (a) being a first modified version and (b) being a second modified version. FIG. 9 is a view showing a conventional lever-type hoisting and traction device.

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0017] FIG. 1 is a perspective view showing an entire lever-type hoisting device 1 of the present invention, with a part cut away and in cross section.

[0018] A hoist drum 4 is disposed inside plate-like main bodies 2 arranged in parallel. A lever 10 for operating the rotation of this hoist drum 4 is attached to a base 12 via a ratchet mechanism. The base 12 is threadedly engaged with a threaded portion 6a formed on the circumferential surface of a drive shaft 6 fixed to the hoist drum 4 so as to be movable integrally therewith.

[0019] A knob 14 is provided separately from the lever 10 for rotating the base 12. The knob 14 is connected to the base 12 via a spacer 18 and a plate-shaped base restriction portion 20, which will be described in detail later using Figure 7. The knob 14 is fixed to the end of the drive shaft 6 with a bolt 22. Although the knob 14 is fixed with the bolt 22, it is rotatable relative to the drive shaft 6, and rotational force cannot be transmitted directly from the knob 14 to the drive shaft 6.

[0020] As described above, the rotational force input by the user from the lever 10 or the knob 14 is transmitted to the drive shaft via the base 12, and the hoisting drum 4 performs the hoisting and lowering operations.

[0021] The ratchet wheel 8 is disposed on the opposite side of the knob 14 (the lower side in the drawing) with respect to the base 12. The ratchet wheel 8 is provided so that rotation of the hoist drum 4 in the lowering direction can be restricted by a pawl 24 provided on the outer surface of the main body 2. The pawl 24 is biased toward the ratchet wheel 8, and by rotating it against the bias, the restriction on rotation of the ratchet wheel 8 in the lowering direction can be released.

[0022] A disk-shaped abutment plate 26, with which the ratchet wheel 8 can come into frictional contact, is provided between the ratchet wheel 8 and the main body 2. This abutment plate 26 is disposed so as to contact the lower end of the threaded portion 6a of the drive shaft 6. The abutment plate 26 is fixed to the drive shaft 6 so as to be able to move integrally with it. The threaded portion 6a of the drive shaft 6 is formed so that the base 12 threads toward the ratchet wheel 8 when the lever 10 or the knob 14 is rotated in the winding direction.

[0023] As described above, a mechanical brake is formed by the base 12, the ratchet wheel 8, and the abutment plate 26. When the ratchet wheel 8 is clamped and fixed between the base 12 and the abutment plate 26, the ratchet wheel 8, whose rotation in the lowering direction is restricted by the pawl 24, and the abutment plate 26 in pressure contact with it are prevented from rotating in the lowering direction. In other words, the hoist drum 4, which is fixed integrally with the abutment plate 26, can be prevented from rotating in the reverse direction.

[0024] Figure 2 is a perspective view showing an exploded state of the lever-type hoisting device 1 of Figure 1. Here, the structure connecting the hoist drum 4 side to the knob 14 will be explained in order.

[0025] The hoist drum 4, contact plate 26, and drive shaft 6 are configured to be movable as a single unit. The ratchet wheel 8 is disposed so as to cover the contact plate 26. As described above, the main body 2 is provided with a pawl 24 that can restrict rotation of the ratchet wheel 8 in the winding-down direction. The pawl 24 is biased toward the ratchet wheel 8 by a spring. When the pawl 24 is moved away from the ratchet wheel 8 against this bias, the ratchet wheel 8 can rotate freely in either the winding-up or winding-down direction.

[0026] The base 12 is disposed so as to overlap the ratchet wheel 8. For ease of explanation, Fig. 2 shows the base 12 removed from the lever 10. Teeth are also formed around the periphery of the base 12, which form a ratchet mechanism between the base 12 and the lever 10. A thread 12a is formed on the inside of the base 12 to thread onto the threaded portion 6a of the drive shaft 6. Furthermore, fitting holes 16b are formed in two locations on the top surface of the base 12.

[0027] The base restricting portion 20 is disposed so as to overlap the base 12. A through hole 20a is formed in the center of the base restricting portion 20 for fixing to the drive shaft 6. The base restricting portion 20 is fixed to the drive shaft 6 by this through hole 20a so as to be able to move integrally with the drive shaft 6. In addition, arc-shaped elongated holes 20b are formed on the periphery of the through hole 20a. The two elongated holes 20b are formed so as to align with the fitting holes 16b of the base 12 in the radial direction.

[0028] Furthermore, a spacer 18 is arranged so as to overlap the base restriction portion 20. Two fitting shafts 16a extending parallel to the drive shaft 6 protrude from the base 12 side of the spacer 18 (the lower side in the drawing). These fitting shafts 16a are formed at positions where they can pass through elongated holes 20b of the base restriction portion 20 and fit into fitting holes 16b of the base 12. In this way, a connecting structure 16 (see FIG. 3) is formed between the spacer 18 and the base 12, and is fitted parallel to the axial direction of the drive shaft 6.

[0029] A through hole 18b formed in the center of the spacer 18 is formed to allow a bolt 22 to pass through to the drive shaft 6 side, and is not fixed to the drive shaft 6 like the base restriction part 20. Two fitting holes 17b are formed in the surface of the plate-like part 18a of the spacer 18 opposite the side on which the fitting shaft 16a is formed. Two fitting shafts 17a (described later using FIG. 6) formed below the knob 14 are fitted into these fitting holes 17b.

[0030] In this way, a connecting structure 17 (see FIG. 3) is formed between the spacer 18 and the knob 14, similar to the above, which is fitted in parallel with the axial direction of the drive shaft 6.

[0031] As will be described in detail later with reference to FIG. 7, the connecting structures 16 and 17 in the configuration according to this embodiment are formed at 90 degrees apart in the circumferential direction around the drive shaft 6 as the center.

[0032] The knob 14 for inputting the rotational force is attached to the drive shaft 6 by means of a bolt 22 .

[0033] 3 is a cross-sectional view showing the operation of the lever-type hoisting device 1 in the hoisting state. In FIG. 3, for the sake of convenience, parts that operate together are shaded.

[0034] 3 shows a state in which the hoist drum 4 is rotated in the hoisting direction by the lever 10. The lever 10 rotates the directly connected base 12. This rotation causes the base 12 to be fed toward the ratchet wheel 8 along the threaded portion 6a formed on the circumferential surface of the drive shaft 6.

[0035] 3 because it is very small compared to the overall dimensions, there is a small gap that allows the base 12 to move axially when it rotates slightly along the threaded portion 6a. When the base 12 advances to fill this gap and is screwed onto the ratchet wheel 8, the ratchet wheel 8 is clamped and fixed between the base 12 and the abutment plate 26.

[0036] 3 allows rotation in the winding direction relative to the ratchet wheel 8, so that the base 12, ratchet wheel 8, and abutment plate 26, which are integrated together, rotate in the winding direction by operating the lever 10. As a result, the drive shaft 6 and hoist drum 4, which are configured to be movable integrally with the abutment plate 26, are wound up.

[0037] At this time, the base restricting portion 20, which is fixed to the drive shaft 6 so as to be movable integrally with the drive shaft 6, also rotates. Also, the spacer 18, which is connected to the base 12 via the connecting structure 16, and the knob 14, which is connected to the spacer 18 via the connecting structure 17, also rotate.

[0038] Figure 4 shows the state of the lever-type hoisting device 1 during the hoisting operation, where (a) is a cross-sectional view showing the state in which the base 12 is not fastened to the drive shaft 6, and (b) is a partially enlarged view of the state in (a).

[0039] As in the case of Fig. 3, parts that operate together are shaded. However, unlike the case of Fig. 3, this shows a state in which the knob 14 is being rotated in the unwinding direction. Immediately after the state of rotation in the winding direction of Fig. 3 is shifted to the state of rotation in the unwinding direction, as shown in Fig. 4(b), a slight gap G1 is formed between the base 12 and the base regulating part 20, allowing the base 12 to thread toward the spacer 18.

[0040] Because knob 14 is connected to spacer 18 via connecting structure 17, the rotational force applied to knob 14 is transmitted to spacer 18. And because spacer 18 is connected to base 12 via connecting structure 16, the rotational force transmitted to spacer 18 is transmitted to base 12. However, when lever 10 is not being operated, the ratchet mechanism between lever 10 and base 12 allows rotation of base 12 in the lowering direction, so base 12 rotates freely and lever 10 is stopped.

[0041] As described above with reference to Figure 3, a gap G1 is formed that allows the base 12 to move slightly along the threaded portion 6a of the drive shaft 6, and the base 12 can be threaded toward the knob 14 within the range of this gap G1.

[0042] 4(a) shows a state in which the base 12 is threadedly advanced relative to the drive shaft 6, and it can be seen that the structure provided so as to be movable integrally with the drive shaft 6 is in a stopped state. Also, as can be seen in FIG. 4(b), which shows a partially enlarged view of the area surrounded by the two-dot chain line in FIG. 4(a), the base restriction portion 20 fixed so as to be movable integrally with the drive shaft 6 is also in a stopped state together with the drive shaft 6.

[0043] That is, until the fitting shaft 16a of the spacer 18 reaches the circumferential end position within the range of the elongated hole 20b (see Figure 2) formed in a curved shape in the base regulating portion 20, the drive shaft 6 side that does not interfere remains stopped, and only the base 12 side is allowed to rotate in the lowering direction.

[0044] The ratchet wheel 8 can rotate independently of the drive shaft 6, but because its rotation in the lowering direction is restricted by a pawl 24, the position of which is shown by a dotted line for convenience, it cannot rotate in the lowering direction together with the base 12 and is therefore stopped.

[0045] 5 shows the operation of the lever-type hoisting device 1 in the lowering state, with (a) being a cross-sectional view showing the state in which the base 12 is fastened to the drive shaft 6, and (b) being a partially enlarged view of the state in (a). As in the case of Fig. 4, the parts that operate together are shaded, and the state in which the knob 14 is rotated in the lowering direction is shown.

[0046] Rotating the knob 14 rotates the spacer 18, which is directly connected via the connecting structure 17, and the base 12, which is indirectly connected, in the unwinding direction, just as in the case of Fig. 4. However, this state differs from the state of Fig. 4 in that the fitting shaft 16a of the spacer 18 has reached the circumferential end position of the elongated hole 20b (see Fig. 2) of the base restriction portion 20.

[0047] As a result, the fitting shaft 16a of the spacer 18 transmits a force in the lowering direction to the base restriction part 20. As a result, the drive shaft 6, which is fixed to the base restriction part 20 so as to be able to move integrally with it, also rotates in the lowering direction.

[0048] As can be seen in Figure 5(b), unlike the state in Figure 4(b), the base restriction portion 20 is rotating together with the spacer 18. Furthermore, the gap G1 (see Figure 4) between the base 12 and the base restriction portion 20 shown in Figure 4(b) has almost completely closed, and instead, a gap G2 has appeared between the base 12 and the ratchet wheel 8.

[0049] In this way, the components other than the lever 10 holding the base 12 in an idling state and the ratchet wheel 8 restrained by the pawl 24 rotate together in the lowering direction by operating the knob 14.

[0050] When the base 12 is rotated in the winding-down direction by the knob 14, the base 12 is fed toward the base restriction part 20, which is fixed to the shaft end of the drive shaft 6. However, in the configuration according to this embodiment, before the base 12 is screwed into the base restriction part 20, the fitting shaft 16a interferes with the elongated hole 20b of the base restriction part 20, and rotation is restricted. This prevents the base 12 from tightly adhering to the base restriction part 20, making it possible to smoothly switch to operation in the winding-up direction as shown in FIG. 3.

[0051] FIG. 6 is a perspective view of the knob 14 as seen from the bottom side.

[0052] Two fitting shafts 17a are erected below the knob 14 so as to extend in the axial direction of the drive shaft 6. Here, for the components other than the knob 14 that need to be explained, refer to Figure 2 as appropriate.

[0053] As described above, in the configuration according to this embodiment, the fitting shaft 16a formed on the spacer 18 and the fitting shaft 17a formed on the knob 14 are formed to protrude in the same direction (downward), so it is possible to use a plurality of spacers 18 formed in the same shape by stacking them together. This allows the distance between the knob 14 and the base 12 to be freely changed depending on the work environment.

[0054] Also, instead of stacking a plurality of spacers 18, it is possible to replace the spacers with spacers having different dimensions of the plate-like portions 18a.

[0055] Furthermore, if the length of the fitting shaft 17a formed on the knob 14 is long enough to pass through the long hole 20b of the base regulating portion 20, it is possible to use it in a configuration without the spacer 18 depending on the situation.

[0056] As described above, according to the configuration of this embodiment, the distance between the base 12 and the knob 14 can be easily changed depending on the working environment.

[0057] 7A and 7B show the spacer 18, with (a) being a partially enlarged front view of the fitting shaft 16a, and (b) being a perspective view of the entire spacer 18. FIG.

[0058] As shown in FIG. 7B, when the spacer 18 rotates in the direction of arrow A, the fitting shaft 16a receives a reaction force F1 from the mating base 12 (see FIG. 2) in the direction opposite to the rotation direction.

[0059] 7(a) shows how a bending moment acting on the fitting shaft 16a due to the reaction force F1 generates a compressive stress F2 and a tensile stress F3 in the plate-like portion 18a of the spacer 18. These stresses F2 and F3 cause distortion in the plate-like portion 18a near the fitting shaft 16a. As shown in FIG. 7(a), the compressive stress F2 generates a force F4 that lifts the surface of the plate-like portion 18a. Furthermore, the tensile stress F3 generates a force F5 that pulls down the surface of the plate-like portion 18a.

[0060] 7B, the area of ​​the plate-like portion 18a on which a force F4 acts to lift it up is shaded with solid diagonal lines, and the area on which a force F5 acts to pull it down is shaded with dotted diagonal lines.

[0061] On the other hand, in the vicinity of the fitting hole 17b formed on the upper surface of the plate-like portion 18a of the spacer 18, an area for lifting up the plate-like portion 18a and an area for pulling down the plate-like portion 18a are similarly formed based on the bending moment of the fitting shaft 17a (see Figure 6) of the knob 14 (see Figure 2) that is fitted in.

[0062] In FIG. 7B, the area in the vicinity of the fitting hole 17b where the plate-like portion 18a is raised is indicated by solid diagonal lines, and the area where it is lowered is indicated by dotted diagonal lines.

[0063] In this way, regions where the lifting force F4 acts and regions where the pulling force F5 acts are formed alternately in the circumferential direction in the plate-like portion 18a of the spacer 18 that receives the rotational force. In other words, the lifting and pulling forces are offset in the region between the fitting shaft 16a and the fitting hole 17b, which has the effect of reducing distortion occurring in the plate-like portion 18a of the spacer 18.

[0064] The base restriction portion 20 (see FIG. 2) according to this embodiment is formed of a thin plate-like member, so when it is interposed between the fitting shaft 16a and the fitting hole 16b (see FIG. 2), the dimensions of the fitting shaft 16a can be designed to be small. This makes it possible to minimize the influence of the bending moment of the fitting shaft 16a. This in turn effectively reduces the distortion occurring in the plate-like portion 18a as described above.

[0065] <Modifications> Figure 8 shows modifications of the lever-type hoisting device of Figure 1, with (a) being a schematic diagram showing a first modification and (b) being a schematic diagram showing a second modification. For ease of explanation, Figure 8 shows a schematic representation of the connecting structure of the base, spacer, and knob, and does not depict the base regulating portion. Also, Figure 7 shows an example of a configuration in which the connecting structures at the top and bottom of the spacer are formed 90 degrees apart in the circumferential direction, but Figure 8 conceptually shows only the relationship between the protrusions and recesses without showing the difference in three-dimensional position in the circumferential direction. Therefore, the configuration in which the connecting structures are formed apart in the circumferential direction, as in the configuration of Figure 7, is also included.

[0066] 8A shows a first modified example in which a fitting shaft 36a is formed on the lower side of the spacer 38 and a fitting shaft 37a is also formed on the upper side. In contrast, a fitting hole 36b into which the fitting shaft 36a fits is formed on the base 32 side, and a fitting hole 37b into which the fitting shaft 37a fits is formed on the knob 34 side.

[0067] In this way, even when the mating shafts 36a, 37a are formed on both the top and bottom sides of the spacer 38, the relationship between the side of the mating shafts 36a, 37a to which the rotational force is input and the other side (which receives the reaction force from the connected part) is the same as in the case of the spacer 18 in Figure 7 described above.

[0068] Therefore, when the upper and lower fitting shafts 36a, 37a are arranged 90 degrees apart in the circumferential direction around the drive shaft 6 (see FIG. 1), the distortion occurring in the plate-like portion 38a of the spacer 38 is similarly reduced.

[0069] The second modified example shown in Figure 8(b) shows a configuration in which a fitting hole 36b is formed on the lower side of a spacer 48 and a fitting shaft 37a is formed on the upper side. This spacer 48 has a configuration in which the spacer 18 in Figure 7 is inverted upside down. In addition, the fitting shaft 36a that fits into the fitting hole 36b is formed on the base 42 side, and the fitting hole 37b that fits the fitting shaft 37a is formed on the knob 44 side.

[0070] If the lengths of the fitting shafts 36a, 37a and the depths of the fitting holes 36b, 37b are set to appropriate dimensions that allow for combination, it is also possible to use a plurality of spacers 48 of the same shape stacked one on top of the other.

[0071] 7, the effect of reducing distortion of the plate-like portion 48a of the spacer 48 can also be obtained.

[0072] The configuration described above is one example of the present invention, and further includes the following modifications.

[0073] (1) In the above embodiment, the lever 10 is connected via a ratchet mechanism. However, the present invention is not limited to this configuration, and the lever may be a continuous rotation lever connected to the base without a ratchet mechanism.

[0074] (2) In the above embodiment, an example was shown in which the base restricting portion 20 was provided between the base 12 and the spacer 18 as a configuration for restricting rotation. However, a configuration in which the base restricting portion 20 is provided between the knob 14 and the spacer 18 may be used as long as it is a configuration for restricting rotation of the base 12 relative to the drive shaft 6.

[0075] (3) In the above embodiment, the connecting structure 16 formed on one surface of the plate-like portion 18a constituting the spacer 18 is circumferentially spaced 90 degrees from the connecting structure 17 on the other surface. However, the 90-degree separation is not limited to this configuration as long as the strain caused by the connecting structure on one surface and the strain caused by the connecting structure on the other surface are offset in the axial direction. Furthermore, connecting structures each consisting of a fitting shaft and a fitting hole may be provided at three or more locations in the circumferential direction.

[0076] (4) In the above embodiment, the elongated hole 20b of the base restriction portion 20 is curved in an arc shape. However, the elongated hole is not limited to a curved elongated hole as long as it is capable of restricting the relative movement of the fitting shaft 16a in the circumferential direction. For example, to prevent the intrusion of foreign matter, the outer periphery may remain arc-shaped, and the center may be hollowed out to a large extent.

[0077] (5) In the above embodiment, the fitting shafts 16a and 17a constituting the connecting structures 16 and 17 are formed integrally with the spacer 18 and the knob 14, respectively. However, as long as the connecting structure can fit onto the drive shaft 6 in the axial direction and can prevent relative movement in the circumferential direction, the fitting shafts may be formed separately from the spacer and the knob. For example, the base, spacer, and knob may all have fitting holes formed therein into which fitting shafts of separate members can fit.

[0078] (6) In the above embodiment, an example has been given of a configuration in which the ratchet wheel 8 is clamped and fixed between the abutment portion 26, which extends in a disk shape in the radial direction of the drive shaft 6, and the base 12. However, a similar effect can be obtained as long as the base 12 is capable of clamping and fixing the ratchet wheel 8 to at least a configuration that can move integrally with the drive shaft 6. For example, a configuration in which the ratchet wheel is clamped and fixed between the side surface of the hoist drum or the like and the base, without using a configuration such as the abutment plate 26, may also be used.

[0079] REFERENCE SIGNS LIST 1 Lever-type hoisting device 2 Main body 4 Hoist drum 6 Drive shaft 6a Threaded portion 6b Friction surface 8 Ratchet wheel 10 Lever 12 Base 12a Screw 14 Knob 16, 17 Connecting structure 16a, 17a Fitting shaft 16b, 17b Fitting hole 18 Spacer 18a Plate-shaped portion 18b Through hole 20 Base regulating portion 20a Through hole 20b Elongated hole 22 Bolt 24 Claw 26 Contact plate A Arrow F1 Reaction force F2, F3 Stress F4, F5 Force G1, G2 Gap

Claims

1. A lever-type hoisting device comprising: a ratchet wheel rotatably attached to a drive shaft that drives a hoist drum inside a main body, and whose rotation toward the unwinding side can be switched between regulated and released on the main body side; a base that is screwed onto a screw formed on the circumferential surface of the drive shaft and that screws forward to clamp and fix the ratchet wheel between a structure that can move integrally with the drive shaft by rotating a connected lever toward the winding side; a knob that is formed with a smaller diameter than the lever in the radial direction centered on the drive shaft and can rotate the base; a spacer that is interposed between the base and the knob and forms a connecting structure consisting of an engaging shaft and an engaging hole that engage with the base and the knob, respectively, in the axial direction of the drive shaft; and a base regulating part that is fixed to the drive shaft and regulates the base from rotating in a direction away from the ratchet wheel by stopping the engaging shaft.

2. A lever-type hoisting device as described in claim 1, characterized in that the base regulating portion is a plate-like member having a structure for restricting rotation of the engaging shaft around the drive shaft.

3. A lever-type winding device as described in claim 2, characterized in that the engaging shaft in the connecting structure on the base side and the engaging shaft in the connecting structure on the knob side are arranged 90 degrees apart in the circumferential direction centered on the drive shaft.

Images