Rotary locking device and hoist

Abstract

The present application provides a kind of rotation locking device and winch capable of preventing shaft-like member from being unable to rotate due to accidental work when shaft-like member is rotated to winding direction;The retaining plate (140) of rotation locking device (100) has guide groove (145) that is engaged with limiting protrusion (131) and keeps limiting member (130) to the specified position in the radial direction of limiting member support member (120), third limiting wall (145d1) is provided on the other side of the circumferential direction of guide groove (145), the third limiting wall (145d1) is engaged with limiting member (130) by the position protruding to the outer diameter side of the limiting member (130), so as to prevent retaining plate (140) from rotating relative to limiting member support member (120) to the second rotation direction opposite to the first rotation direction, when limiting protrusion (131) is engaged with third limiting wall (145d1), it is located at the position where limiting member (130) and limiting member locking means (120) are not engaged.

Description

Technical Field

[0001] This invention relates to a rotary locking device and a winch. Background Technology

[0002] Lever hoists are widely used for lifting, pulling, and securing goods using slings or similar means. By manually operating the lever, the lever hoist can wind and unwind the chain. One example of such a lever hoist is shown in Patent Document 1. In the lever hoist shown in Patent Document 1, in addition to the previously existing braking mechanism (mechanical brake), two centrifugal force members (31) and a housing ring (35) for housing the centrifugal force members (31) are provided on the pinion gear, closer to the operating handle (12) than the frame (2B). The centrifugal force members (31) are pressed against the inner circumference of the housing ring (35) by centrifugal force. This reduces the speed at which the goods fall.

[0003] Furthermore, the aforementioned braking mechanism (mechanical brake) is configured, for example, as shown in Patent Document 2. This braking mechanism includes: a pressure member (7) mounted non-rotatably on the drive shaft (4), a drive member (8) screwed onto the drive shaft (4), a pair of brake plates (10a, 10b), an anti-reverse ratchet (11), and a pawl (12) mounted on the pawl shaft (15). Moreover, by applying force to the pawl (12) using a spring (13), the pawl (12) engages with the locking teeth (11a) of the ratchet (11). This engagement prevents the ratchet (11) from reversing, thus creating a mechanism that applies braking force to the drive shaft (4) during rotation in the unwinding direction.

[0004] [Existing Technical Documents]

[0005] [Patent Documents]

[0006] Patent Document 1: German Patent, DE102015121581A1

[0007] Patent Document 2: Japanese Patent Application Publication No. 2008-230726 Summary of the Invention

[0008] (The problem that the invention aims to solve)

[0009] However, during the winding operation of hoists (lever hoists or chain hoists), if, for example, a mis-engagement or damage occurs between the locking teeth (11a) of the ratchet (11) and the pawl (12) in a braking mechanism (mechanical brake) equipped with a ratchet mechanism, as shown in Patent Document 2, the brake may fail to function. This ratchet mechanism has a ratchet with multiple teeth formed on its outer periphery and a pawl member that engages with these teeth. When the brake fails to function, the following may occur: under the load of the suspended cargo, the load pulley wound around the chain begins to rotate violently in the unwinding direction, causing the cargo to fall.

[0010] In the event of a malfunction in the braking mechanism, in the structure disclosed in Patent Document 1, the centrifugal force member (31) is pressed against the inner circumferential surface of the outer bushing (35) by utilizing centrifugal force, thereby slowing down the falling speed of the goods (i.e., the rotational speed of the pinion). However, it is not possible to stop the falling of the goods.

[0011] Furthermore, in the structure shown in Patent Document 2, the pawl shaft (15) is mounted on the frame (1b) by pressing or other methods. However, since the frame (1b) is relatively thin, if the length of the pawl shaft (15) increases, the torque acting on the pawl shaft (15) also increases. Therefore, it is necessary to correspondingly improve the strength of the pawl shaft (15) and its mounting part. However, when the pawl shaft (15) is mounted on the hole of the frame (1b) by pressing, the improvement in its mounting strength is limited.

[0012] Therefore, a rotary locking device is being developed that can reliably stop the falling (rotating in the unwinding direction) of goods even in the event of a brake device malfunction or other problems.

[0013] However, in the rotary locking device developed above, when the lower hook installed at the lower end of the load chain is attached to the suspended goods, and a winding operation is to be started, if the load chain is slack, it takes time to eliminate the slack during the lever operation. Therefore, in the workplace, sometimes a method is used to eliminate the slack of the load chain all at once by forcefully pulling the unloaded side of the load chain during the winding action. However, in the aforementioned rotary locking device, when the slack of the load chain is eliminated, the rotation of the shaft member stops abruptly or decelerates rapidly. In this case, there is a possibility that the rotary locking device may unexpectedly activate even though the goods have not actually fallen (the movement is in the winding direction), thus creating the problem of having to restore the rotary locking device.

[0014] The present invention was made in view of the above circumstances, and its object is to provide a rotation locking device and a winch that can reliably stop the rotation of the shaft member in the unwinding direction even in the event of a brake device failure, and can prevent the shaft member from being unable to rotate due to accidental operation when the shaft member is being rotated in the winding direction.

[0015] (A solution to the problem)

[0016] To address the aforementioned issues, according to a first aspect of the present invention, a rotary locking device is provided, which has the following features.

[0017] The rotation locking device comprises: a limiting member support member mounted on a shaft-shaped member and rotating integrally with the shaft-shaped member; a limiting member supported on the limiting member support member in a state capable of sliding outward from the axial side of the shaft-shaped member; a retaining plate configured as a disc and rotatable relative to the limiting member support member, which holds the limiting member in a predetermined position on the limiting member support member; a force-applying means that, by applying force, causes the retaining plate to rotate relative to the limiting member support member in a first rotation direction; and a limiting member locking means that stops the rotation of the shaft-shaped member by engaging with the limiting member; the limiting member has a limiting protrusion protruding toward the retaining plate; the retaining plate has a guide groove that engages with the limiting protrusion and holds the limiting member in a predetermined radial position on the limiting member support member; the guide groove has a first limiting wall and a second limiting wall; the first limiting wall engages with the limiting member in a predetermined radial position and is formed by the interaction of the limiting member with the shaft-shaped member support member. The components are formed by concentric arcs. The second limiting wall engages with the limiting member at a position where it protrudes from a predetermined position in the radial direction toward the outer diameter side. The second limiting wall is provided on one side of the guide groove in the circumferential direction. When the shaft-shaped member accelerates its rotation in the first rotation direction, it resists the force of the force-applying means, causing the limiting member support member and the retaining plate to rotate relative to each other. When the locking between the limiting protrusion and the first limiting wall is released, the limiting member protrudes from the predetermined position toward the position where it engages with the limiting member locking means, thereby stopping the rotation of the shaft-shaped member. Furthermore, a third limiting wall is provided on the other side of the guide groove in the circumferential direction. This third limiting wall engages with the limiting member at a position where it protrudes from the predetermined position in the radial direction toward the outer diameter side, thereby preventing the retaining plate from rotating relative to the limiting member support member in a second rotation direction opposite to the first rotation direction. When the limiting protrusion engages with the third limiting wall, it is located at a position where the limiting member and the limiting member locking means are not locked.

[0018] Furthermore, in the above invention, it is preferable that a reset guide wall is provided at a position on the other side of the circumference relative to the third limiting wall, for returning the limiting member to a predetermined position on the axial side, the reset guide wall being inclined in such a way that it is inclined toward the radial inner diameter side as it moves from one side of the circumference to the other.

[0019] Furthermore, in the above invention, it is preferable that the third limiting wall and the reset guide wall are disposed on the inner wall of the moving limiting groove.

[0020] Furthermore, in the above invention, it is preferable that the limiting member support member is made of a soft magnetic material, and that a magnet is installed on at least one of the radial inner diameter side of the limiting member and the opposing part of the limiting member support member, applying magnetic force in a direction of mutual attraction.

[0021] Furthermore, in the above invention, it is preferable that magnets that apply magnetic force in the direction of mutual attraction are respectively installed on the radial inner diameter side of the limiting member and the opposing part of the limiting member support member.

[0022] Furthermore, in the above invention, it is preferable that the retaining plate is provided with a protruding means protruding from the surface or back of the retaining plate, and the protruding means is positioned such that when the retaining plate is oriented toward the first rotation direction by the force applied by the force application means, it abuts against the side of the limiting member support member before or at the moment of contact with the end of the limiting protrusion and the guide groove on the opposite side of the first rotation direction.

[0023] Furthermore, in the above invention, it is preferable that the retaining plate is provided with a spring support protrusion, which is formed by bending a part of the retaining plate and is positioned closer to the outer diameter side of the retaining plate than the force application means. The spring support protrusion prevents the force application means from falling off to the outer diameter side due to the centrifugal force when the retaining plate rotates.

[0024] In addition, in order to solve the above-mentioned problems, according to a second aspect of the present invention, a winch is provided, which has the following features.

[0025] The winch comprises: a load pulley supported by a shaft on a pair of frames and around which a chain for lifting goods is wound; a drive shaft connected to the load pulley via a reduction gear; a braking device mounted on the drive shaft; and an operating lever, by operating the operating lever, driving the load pulley to rotate in the winding and unwinding direction; the outer periphery of the drive shaft is provided with the rotation locking device of each of the above inventions, the shaft-shaped member being the drive shaft, and the limiting member locking means being mounted on the frame.

[0026] (Invention effect)

[0027] According to the present invention, a rotation locking device and a winch are provided that can reliably stop the rotation of the shaft member in the unwinding direction even in the event of a brake device malfunction, and can prevent the shaft member from being unable to rotate due to accidental operation when the shaft member is being rotated in the winding direction. Attached Figure Description

[0028] Figure 1This is a front view showing an example structure of a lever hoist equipped with the rotary locking (cargo drop prevention) device according to the first embodiment of the present invention.

[0029] Figure 2 It means Figure 1 The diagram shows a cross-sectional view of the structure of the lever hoist.

[0030] Figure 3 It means Figure 1 A cross-sectional view of the structure near the rotary locking (cargo falling prevention) device in the lever hoist shown.

[0031] Figure 4 It means Figure 3 An exploded perspective view of the structure of the rotary locking (cargo drop prevention) device shown.

[0032] Figure 5 It means Figure 1 The diagram shows the limiting component in the lever hoist, and a top view of the guide groove is shown in perspective.

[0033] Figure 6 It means Figure 1 The front view of the retaining plate located on the X1 side of the lever hoist shown.

[0034] Figure 7 It means Figure 1 The front view of the retaining plate located on the X2 side of the lever hoist shown.

[0035] Figure 8 It means Figure 1 The diagram shows the structure near the rotary locking (cargo drop prevention) device in the lever hoist, and provides a perspective view of the positional relationships of the various parts before the rotary locking (cargo drop prevention) device is activated.

[0036] Figure 9 It is a perspective representation from Figure 8 The diagram shows the positional relationship of various parts after the limiting member support member and the retaining plate rotate relative to each other, thereby allowing the limiting protrusion to reach the allowable groove.

[0037] Figure 10 It is a perspective representation from Figure 9 The diagram shows the positional relationship of the limiting member protruding outwards from the outer diameter side, and the limiting protrusion in the state after returning to the limiting groove.

[0038] Figure 11 It is a perspective representation from Figure 8 The diagram shows the positional relationship of various parts after the limiting member support member and the retaining plate rotate relative to each other, thereby allowing the limiting protrusion to enter the movement limiting groove.

[0039] Figure 12 It is an enlarged representation Figure 11 A diagram showing the positional relationship near the movement restriction groove in the state shown.

[0040] Figure 13 It means magnification from Figure 12 The diagram shows the state after the limiting protrusion slides along the reset guide wall under the action of the applied force spring.

[0041] Figure 14 A variation of the present invention is shown in a diagram where a magnet is disposed in a recess on the bottom surface side of the limiting member 130, and a magnet is also disposed in a recess on the bottom surface side of the limiting member support member.

[0042] Figure 15 (A) indicates that in Figure 14 The diagram shows the state where the two magnets are separated by a distance Y in the structure shown. (B) represents the state where... Figure 5 The diagram shows the state in which the bottom surfaces of the magnet and the limiting member are separated from each other by a distance Y / 2. Detailed Implementation

[0043] [First Implementation Method]

[0044] The first embodiment of the lever hoist 10 of the present invention will now be described with reference to the accompanying drawings. In the following description, the X direction is defined as the axial direction of the drive shaft 25, the X1 side is defined as the side on which the idler handle 60 is mounted, and the X2 side is the gearbox 34 side opposite to it. Furthermore, the Z direction is defined as the vertical direction (suspension direction; winding or unwinding direction) of the lever hoist 10 in its suspended state, the Z1 side is defined as the upper side in the suspended state, and the Z2 side is defined as the lower side in the suspended state. Additionally, the direction perpendicular to the X and Z directions is defined as the Y direction, and the Y1 side is... Figure 1 The middle is on the right side, and the Y2 side is on the right side. Figure 1 The left side is shown in the middle. Furthermore, in the following description, regarding the rotation direction of the load sheave 20, the unwinding direction is defined as one rotation direction, and the winding direction as another. Additionally, the rotation direction around the axis connected to the load sheave 20 is based on the direction in which the load sheave 20 rotates.

[0045] <About the overall structure of a lever hoist>

[0046] Figure 1 This is a front view showing an example structure of the lever hoist 10 according to the first embodiment of the present invention. Figure 2 It means Figure 1 The diagram shows a cross-sectional view of the structure of the lever hoist 10.

[0047] like Figure 2As shown, the load pulley 20, which is attached to the chain C1, is supported in a rotatable manner between a pair of frames 11 and 12 of the lever hoist 10. A load gear 21, which meshes with the small-diameter gear portion 32 of the reduction gear 30 (described later), is provided on the load pulley 20 in a non-rotatable manner. The detailed structure of the load pulley 20 will be explained later.

[0048] Furthermore, the load pulley 20 has a through hole 20a extending axially (X direction), and the drive shaft 25 is inserted into the hollow hole of the load pulley 20. It should be noted that the drive shaft 25 corresponds to a shaft-shaped member. A male threaded portion 26 is provided on the outer periphery of the drive shaft 25, which meshes with the female threaded member 35 constituting the braking device 70 described later. A small gear 27 is provided on the other end side (X2 side) of the drive shaft 25, which meshes with the large-diameter gear portion 31 of the reduction gear 30. Additionally, a small-diameter gear portion 32 that meshes with the load gear 21 is integrally provided on the reduction gear 30.

[0049] Additionally, a housing 13 is mounted on the frame 11 to protect the drive components such as the reduction gear 30 or load gear 21. Furthermore, the male threaded portion 26 engages with the female threaded portion 36 of the female threaded member 35. In addition to the female threaded portion 36, the female threaded member 35 is also provided with a switching gear 37 that can engage with a switching pawl 40 disposed on the operating lever 50. The switching pawl 40, for example, has a pawl on each side; by swinging the operating lever 50 while the switching pawl 40 is engaged with the switching gear 37, driving force is transmitted to the female threaded member 35.

[0050] Additionally, the switching knob 45 is coaxially fixed to the switching pawl 40. By switching the knob 45, the transmission of driving force to the female threaded member 35 can be switched to either the winding direction, the unwinding direction, or a neutral position. For example, in... Figure 1 If the lower side (Z2 side) of the switching knob 45 is pushed to the left, the switching pawl 40 for winding engages with the switching gear 37. Thus, by repeatedly swinging the operating lever 50, the switching gear 37 rotates in the winding direction but not in the unwinding direction. This corresponds to the winding state of chain C1.

[0051] On the other hand, for example, if the lower side (Z2 side) of the switching knob 45 is pushed towards Figure 1On the right side, the unwinding pawl 40 engages with the switching gear 37. Thus, when the operating lever 50 is repeatedly swung, the switching gear 37 rotates in the unwinding direction but not in the winding direction. Furthermore, when switched to the neutral position, it can transition to an idle state where the chain C1 can be pulled out by hand (at this time, the load pulley 20 and drive shaft 25 also rotate). Further, the chain C1 can be quickly wound or unwound by operating the idle handle 60 (described later) without operating the operating lever 50.

[0052] Additionally, a cam member 55 is mounted on the drive shaft 25 in a non-rotating state, connected by, for example, a spline connection or a key connection. Furthermore, a member called a freewheeling handle 60 is mounted on the cam member 55 in a manner that allows it to slide axially relative to the cam member 55 by a predetermined amount. Figure 2 In this position, the idler handle 60 is engaged with the cam member 55 in a manner that prevents it from rotating relative to the cam member 55. However, when the idler handle 60 is slid in the X1 direction, it can rotate within a certain range relative to the cam member 55. The idler handle 60 is a generally cylindrical handle-like portion that can rotate with the drive shaft 25 via the cam member 55, and the operator can hold the idler handle 60 by hand.

[0053] The idler handle 60 is connected to the female threaded member 35 via a first torsion spring (not shown), and further connected to one end of the drive shaft 25 via a second torsion spring (not shown). When the switching knob 45 is in the neutral position, the idler handle 60 is moved towards... Figure 2 When the chain slides in the X1 direction, the idler handle 60 rotates a predetermined amount in the unwinding direction using the force of the second torsion spring (idle spring). The first torsion spring mounted on the idler handle 60, which has rotated a predetermined amount, also rotates in the unwinding direction. The force applied to the female thread member 35, which rotates it in the winding direction, is released, and the chain switches to idle mode. Here, regardless of whether it is in idle mode or not, when the operator holds the idler handle 60 and rotates it in the winding direction, rotational force can be transmitted to the drive shaft 25. Therefore, by rotating the idler handle 60, the length of the chain C1 can be quickly adjusted, or the chain can be switched to idle mode by sliding. In addition, even in idle mode, when a predetermined tension or higher is applied to the chain C1 in the unwinding direction, the female thread member 35 rotates relative to the drive shaft 25 in the locking direction, i.e., the winding direction, thereby activating the brake of the braking device 70 described later.

[0054] <Regarding the braking device 70>

[0055] like Figure 2As shown, a braking device 70 is mounted on a drive shaft 25 connected to a load pulley 20 via a gear. The main structural components of the braking device 70 include: a brake support 71, brake plates 72a and 72b, a ratchet 80, a pawl member 90, a pawl shaft 115, a bushing 92, and a female threaded member 35. Furthermore, the ratchet 80, pawl member 90, and pawl shaft 115 correspond to the main structural components of a ratchet mechanism.

[0056] The brake support 71 has a flange portion 71a and a hollow bushing portion 71b. The flange portion 71a is configured such that its diameter is larger than that of the hollow bushing portion 71b, and it is able to abut against the brake plate 72a.

[0057] The hollow bushing portion 71b is located closer to the female thread member 35 (X1 side) than the flange portion 71a, and it supports the ratchet 80 via the bushing 92. In addition, the inner circumference of the hollow bushing portion 71b engages with the drive shaft 25 via a spline connection or the like, thereby allowing the drive shaft 25 and the brake support 71 to rotate integrally.

[0058] Furthermore, brake plates 72a and 72b are axially supported on the hollow bushing portion 71b between the flange portion 71a and the ratchet 80, and between the female thread member 35 and the ratchet 80, respectively. The brake plates 72a and 72b are, for example, friction members formed from a specified friction material into a plate shape, and are disposed on both sides of the ratchet 80 by means of sintering or the like.

[0059] When the female threaded member 35 is rotated in the winding direction, through its interaction with the male threaded portion 26 of the drive shaft 25, the female threaded member 35 presses the ratchet 80 and brake plates 72a and 72b together toward the brake support 71, thereby transmitting driving force to the drive shaft 25. On the other hand, in this state, even if the drive shaft 25 is rotated in the unwinding direction, the female threaded member 35 will still press the ratchet 80 and brake plates 72a and 72b together toward the brake support 71. At this time, the ratchet 80 cannot rotate in the unwinding direction under the action of the pawl member 90, so the braking force generated by friction in the braking device 70 takes effect. Thus, the rotation of the drive shaft 25 in the unwinding direction can be stopped. Conversely, if the female threaded member 35 is rotated in the unwinding direction, the pressing force applied by the female threaded member 35 is correspondingly relieved, the braking force of the braking device 70 is reduced, and thus rotation in the unwinding direction is possible.

[0060] Furthermore, a pawl shaft 115 is integrally provided on the limiting member support member 120 (described later), and the pawl member 90 is rotatably supported on the pawl shaft 115. A coil portion 93a of a torsion spring 93 is mounted on the pawl shaft 115, and the torsion spring 93 applies a force in the direction that presses the pawl member 90 against the ratchet teeth 83 of the ratchet 80. Thus, the ratchet 80 is configured to rotate in the winding direction, and in the unwinding direction, its rotation is limited by a pitch angle divided by the number of teeth of the ratchet 80. Additionally, a pair of pawl members 90 are provided, arranged 180 degrees apart circumferentially from the ratchet 80.

[0061] In addition, such as Figure 2 As shown, the aforementioned braking device 70 is covered by the brake cover 14, thereby preventing dust or rainwater from intruding into the side of the braking device 70 located inside the brake cover 14.

[0062] <Regarding the load-bearing pulley 20 and the rotary locking (cargo falling prevention) device 100>

[0063] Next, the load pulley 20 and the rotation lock (cargo falling prevention) device 100 will be described. Figure 3 This is a cross-sectional view showing the structure near the rotary locking (cargo drop prevention) device 100. Figure 4 It means Figure 3 An exploded perspective view of the structure of the rotary locking (cargo falling prevention) device 100 shown. Figure 3 and Figure 4 As shown, the main structural components of the rotary locking (cargo falling prevention) device 100 include: a limiting member locking member 110, a limiting member support member 120, a limiting member 130, a retaining plate 140, and a force application unit 150. It should be noted that the limiting member locking member 110 corresponds to the limiting member locking means, and the force application unit 150 corresponds to the force application means.

[0064] like Figures 2 to 4 As shown, in this embodiment, a pair of limiting member locking members 110 are installed on the ratchet 80 side of the frame 12. In this embodiment, the limiting member locking member 110 is a long, sheet-like member extending relatively long in the Y direction, and a space SP1 is formed between the two limiting member locking members 110. Therefore, compared with the case where the limiting member locking members are distributed around the entire circumference of the outer periphery of the limiting member support member 120 and the retaining plate 140, the limiting member locking members 110 can be made lighter.

[0065] Each limiting member locking component 110 is mounted on the frame 12 using two stay bolts B1. To enable this mounting, two mounting holes 111 are provided on the limiting member locking component 110, and the stay bolts B1 are inserted into these mounting holes 111. It should be noted that in this embodiment, a pair (two) of mounting holes 111 are provided, but it is also possible to provide three or more.

[0066] Additionally, an inner protrusion 112 is provided on the limiting member locking member 110. The inner protrusion 112 is a portion of the limiting member locking member 110 that protrudes towards the center of the shaft hole 12b of the frame 12. Furthermore, the shaft hole 12b is a hole through which the aforementioned drive shaft 25 and load pulley 20 are inserted.

[0067] The inner protrusion 112 is positioned with a small gap between it and the outer peripheral surfaces of the limiting member support member 120 and the retaining plate 140, which will be described later. This configuration ensures that the rotation of the limiting member support member 120 and the retaining plate 140, which support the limiting member 130 in the retaining position, is not impeded. Furthermore, in this embodiment, one inner protrusion 112 is provided on each limiting member locking member 110. Therefore, two inner protrusions 112 are arranged at 180-degree intervals in the circumferential direction.

[0068] Additionally, a locking wall 114 is provided on the inner protrusion 112. The locking wall 114 is on the other side of the rotation direction of the inner protrusion 112. Figure 3 and Figure 4 The wall surface of the inner protrusion 112 (clockwise direction side) is such that when the limiting member 130, which rotates in a rotational direction (unwinding direction), collides with the locking wall 114 from the limiting member support member 120 radially outward, the rotation of the load pulley 20 can be stopped. Therefore, the radial direction of the locking wall 114 relative to the shaft hole 12b is set at an angle that will not push the limiting member 130 back towards the rotation axis. Furthermore, the side surface of the limiting member 130 also has an angle that will not be pushed back towards the rotation axis due to the collision with the locking wall 114. Additionally, as... Figure 4 As shown, a recessed portion 113 is provided connected to the locking wall 114 and recessed in a direction away from the rotation axis (outer diameter side). A hook portion (not shown) of the torsion spring 93 engages with this recessed portion 113, thereby preventing the movement limiting member 130 from contacting the hook portion of the torsion spring 93.

[0069] In addition, such as Figure 4As shown, a pawl shaft 115 is provided on the limiting member locking member 110. In this embodiment, the pawl shaft 115 is integrated with the other parts of the limiting member locking member 110. To achieve such integration, it is preferable to form the limiting member locking member 110 by casting (e.g., lost-wax casting). However, it is also possible to configure it such that only the pawl shaft 115 is formed separately, and it is installed by pressing the pawl shaft 115 into the mounting holes or the like present in the limiting member locking member 110.

[0070] Here, as Figure 3 As shown in the cross-sectional view, multiple reinforcing ribs 116 are arranged inside the limiting member locking member 110. That is, the limiting member locking member 110 is not a solid member, but a member with a hollow portion composed of multiple reinforcing ribs 116, thus enabling the limiting member locking member 110 to be lightweight. In addition, by arranging two reinforcing ribs 116 in an X-shape on the root side of the pawl shaft 115, it is possible to withstand the load in the axial direction of the pawl shaft 115.

[0071] In addition, in this embodiment, such as Figure 3 As shown, the sidewall of the inner protrusion 112 opposite to the locking wall 114 can also function as the locking wall 114. Alternatively, it can be configured such that the sidewall facing the concave portion 113... Figure 3 and Figure 4 The sidewall on the clockwise side is inclined at a predetermined angle or more relative to the radial direction, so that the limiting member 130 protruding from the limiting member storage part 123 is stored in the limiting member storage part 123 as described later.

[0072] Next, the limiting member support member 120 will be described. The limiting member support member 120 has a central hole 121, through which it is mounted on the drive shaft 25, thereby allowing the limiting member support member 120 and the drive shaft 25 to rotate integrally. Furthermore, regarding the mounting of the limiting member support member 120 to the drive shaft 25, any mounting method such as a locking screw, key connection, or spline connection can be used, as long as the necessary torque can be transmitted.

[0073] In addition, such as Figure 4 As shown, a bearing sleeve portion 122 is provided on the limiting member support member 120. The bearing sleeve portion 122 is a hollow shaft-shaped portion that protrudes along the axial direction (X direction) and is rotatably embedded in the central hole 142 of the retaining plate 140.

[0074] Furthermore, the limiting member support member 120 is provided with a limiting member receiving portion 123 formed from its central hole 121 side toward its outer peripheral side. The limiting member receiving portion 123 is the part that receives the limiting member 130 described later, and its outer peripheral side is open. Therefore, the limiting member 130 received in the limiting member receiving portion 123 can protrude toward its outer peripheral side and is supported by the side wall 123a of the limiting member receiving portion 123 in a slidable manner.

[0075] Furthermore, the limiting member storage portion 123 is formed by clamping a narrow plate portion 120a and a wide plate portion 120b. In the event of the limiting member 130 colliding with the locking wall 114 (described later), the narrow plate portion 120a is located opposite the inner protrusion 112, while the wide plate portion 120b is located away from the inner protrusion 112 (locking wall 114) across the limiting member storage portion 123. Figure 3 In the structure shown, the narrow plate portion 120a is located on the left side of the movement limiting member storage portion 123, and the wide plate portion 120b is located on the right side of the movement limiting member storage portion 123. Here, the wide plate portion 120b is configured such that its circumferential width is wider than that of the narrow plate portion 120a. Therefore, even if the movement limiting member 130 collides with the locking wall 114, it can be ensured that the wide plate portion 120b has sufficient strength to withstand the impact.

[0076] In addition, an insertion hole 124 is provided on the limiting member support member 120. The insertion hole 124 is a recessed hole in the outer peripheral surface of the limiting member support member 120, located at a point that does not interfere with the central hole 121 and the limiting member receiving portion 123. Figure 3 The recess is formed from the outer peripheral surface opposite to the limiting member receiving portion 123. By inserting one end of the locking pin 152 (described later) into the insertion hole 124, the limiting member support member 120 supports one end of the locking pin 152.

[0077] Next, the movement-limiting component 130 will be described. Figure 5 This is a top view showing the limiting member 130 and the guide groove 145. (Example) Figures 3 to 5 As shown, the limiting member 130 is housed within the limiting member housing portion 123 of the aforementioned limiting member support member 120. The limiting member 130 is housed in the limiting member housing portion 123 in a state in which it can slide from the housing position in the centrifugal direction.

[0078] In addition, Figure 3In the structure shown, the bottom surface (inner wall surface on the axis of rotation side) 123a of the limiting member housing 123 has a planar portion, therefore, the bottom surface 130a of the limiting member 130 (the surface located on the inner diameter side of the limiting member housing 123) also has a planar portion. Furthermore, a recess (notation omitted) for mounting the magnet M1 as described later is formed on the bottom surface 130a side of the limiting member 130.

[0079] In addition, such as Figure 3 As shown, when the limiting member 130 is housed in a predetermined position in the limiting member housing 123, the outer peripheral surface (the surface away from the radial center) of the limiting member 130 is located on the inner diameter side relative to the rotation axis center, compared to the outer peripheral surface of the limiting member support member 120.

[0080] Here, a cylindrical limiting protrusion 131 is provided on the limiting member 130. The limiting protrusion 131 protrudes from the surface (surface and back) of the limiting member 130 opposite to the retaining plate 140 toward the retaining plate 140 in the X-axis direction. In addition, as Figure 3 and Figure 4 As shown, the limiting protrusion 131 is positioned closer to the axis of the drive shaft 25 (limiting member 130) than the center of the limiting member 130 in the depth direction (radial direction of the limiting member support member 120). Alternatively, the limiting protrusion 131 can be integrally formed with the limiting member 130, but it can also be configured such that a mounting hole is provided on the limiting member 130, allowing a shaft-like member or pin to fit into the mounting hole, thereby forming the limiting protrusion 131.

[0081] The limiting protrusion 131 enters the guide groove 145, which will be described later. Thus, when the relative positions of the rotational directions of the limiting member support member 120 and the retaining plate 140 change, the limiting protrusion 131 slides within the guide groove 145. Furthermore, when the limiting protrusion 131 is located in the allowable groove 145a, which will be described later, the limiting member 130 can protrude outwards according to the centrifugal force acting on the limiting member 130 and the pressing force from the second limiting wall 145c1 caused by the force of the force-applying spring 151.

[0082] Here, the outermost radially outer peripheral surface 132 of the limiting member 130 is also arc-shaped, similar to the outer peripheral surface of the limiting member support member 120 or the outer peripheral surface of the retaining plate 140. However, the outer peripheral surface 132 can be straight or other shapes. It should be noted that the radial direction of the limiting member 130 refers to the direction connecting the rotation center of the drive shaft 25 and the outer diameter side (the same applies to other parts of this specification).

[0083] Furthermore, a magnet M1 is mounted on the bottom surface 130a of the limiting member 130. The magnet M1 is a component used to generate a magnetic force that returns the limiting member 130, which protrudes outwards under centrifugal force, to its original retracted position. Specifically, the magnet M1 is positioned opposite the bottom surface 123b of the limiting member retractable portion 123 of the limiting member support member 120, which is made of soft magnetic material. As a result, a magnetic force is generated between the magnet M1 and the bottom surface 123b. Therefore, as the magnet M1 approaches the bottom surface 123b, the magnetic force increases, thereby pulling the limiting member 130 back to its retracted position.

[0084] In addition, magnet M1 also has the function of using magnetic force to resist centrifugal force and suppress the protrusion of the limiting member 130 to the outer diameter side when the limiting member support member 120 and the limiting member 130 are rotating, until the limiting member 130 reaches a certain speed (set speed). Regarding the above-mentioned set speed, it can usually be set to an appropriate speed for high-speed manual pulling when pulling the chain C1 by hand. In addition, since the limiting member 130 is held in the predetermined position of the limiting member storage part 123 (the position where the bottom surface 130a and the bottom surface 123b are in contact; storage position) by using magnetic force, it is possible to suppress the sliding contact between the limiting protrusion 131 of the limiting member 130 and the first limiting wall 145b1 of the holding plate 140 when changing from a stationary state to a rapid acceleration. Therefore, it also has the effect of stabilizing the working value of the relative rotation between the plate 140 and the limiting member support member 120.

[0085] Next, the retaining plate 140 will be described. In this embodiment, two retaining plates 140 with different shapes are provided. In the following description, Figure 4 The retaining plate 140 located on the X1 side is called retaining plate 140A, which will... Figure 4 The retaining plate 140 located on the X2 side is referred to as retaining plate 140B. However, when it is not necessary to distinguish between the two, it is simply referred to as retaining plate 140. Furthermore, a limiting member support member 120 is inserted between retaining plate 140A and retaining plate 140B. Moreover, the retaining plates 140 are connected to each other at predetermined intervals using connecting members R1. Regarding the connection of the retaining plates 140 to each other, it is preferable that they be securely connected as a single unit.

[0086] Figure 6This is a front view showing the retaining plate 140A located on the X1 side. The retaining plate 140A is configured in a disc shape (annular shape) with a central hole 142 at its radial center. By inserting the bearing sleeve portion 122 of the limiting member support member 120 into this central hole 142, the retaining plate 140 is supported by the limiting member support member 120 to be able to rotate coaxially. It should be noted that the distance (i.e., radius) from the center of rotation to the outermost periphery of the retaining plate 140A is approximately the same as the distance to the outermost periphery of the limiting member support member 120. However, the radius of either the limiting member support member 120 or the retaining plate 140A may be set to be larger.

[0087] Figure 7 This is a front view showing the retaining plate 140B located on the X2 side. The retaining plate 140B is formed by multiple circular annular portions (…). Figure 7 The middle part is formed by punching or bending two parts to create a recessed portion that extends from the outer diameter side toward the inner diameter side.

[0088] On one of these recessed portions, a locking protrusion 143 is provided, rising from the surface of the retaining plate 140B. This locking protrusion 143 abuts against the side 120b1 of the wide section 120b of the limiting member support member 120, thereby preventing further rotation even when the limiting member support member 120 is pulled by the force-applying spring 151. In other words, the locking protrusion 143 restricts the rotational position of the limiting member support member 120 relative to the rolling direction of the retaining plate 140B. Therefore, the force exerted by the force-applying unit 150 on the end portion of the limiting protrusion 131 in the second rotational direction of the clearance groove 145b can be suppressed. Thus, the influence of the frictional force generated between the limiting member 130 and the side wall 123a, caused by the force from the force-applying unit 150, on the movement of the limiting member 130 can be reduced, thereby stabilizing the operation of the rotation locking device 100.

[0089] Furthermore, the locking protrusion 143 abuts against the side of the wide sheet portion 120b using its side side. Additionally, the boundary line formed between the locking protrusion 143 and the plate surface is configured such that it does not extend radially along the holding plate 140B, but rather forms a predetermined angle relative to that radial direction. Therefore, it is possible to prevent deformation of the locking protrusion 143 relative to the plate surface from changing its bending angle when the wide sheet portion 120b collides with the locking protrusion 143.

[0090] Additionally, on the other side of the aforementioned recessed portion, a spring support protrusion 144, similarly erected from the surface of the retaining plate 140B, is provided. For example... Figure 3As shown, the spring support protrusion 144 is positioned further away from the outer diameter side of the retaining plate 140B than the force spring 151, thereby preventing the force spring 151 from falling off to the outer diameter side under the action of centrifugal force when the retaining plate 140 rotates.

[0091] Additionally, a guide groove 145 is provided on the retaining plate 140. For example... Figures 5 to 7 As shown, the guide groove 145 is the portion into which the limiting protrusion 131 of the limiting member 130 enters and guides the movement of the limiting protrusion 131. Its appearance is formed as follows: a groove extending in an arc shape is added to the radial center side of the generally triangular portion. Specifically, as... Figures 5 to 7 The generally triangular retaining protrusion 146 shown enters the guide groove 145. Through this entry, the guide groove 145 is provided with a permissive groove 145a, a clearance groove 145b, and a return limiting groove 145c. In addition to these grooves, the guide groove 145 is also provided with a movement limiting groove 145d.

[0092] The permissible groove 145a is a groove that allows the limiting protrusion 131 to move radially. Therefore, in Figures 5 to 7 In this configuration, the inner wall 145a1 located below the allowable groove 145a is configured to be parallel to the radial direction (the direction of a radial line extending from the center of the central hole 142). It should be noted that the width of the allowable groove 145a is defined by the distance between the front end portion 146a of the retaining protrusion 146 that protrudes most towards the inner wall 145a1 and the aforementioned inner wall 145a1.

[0093] Additionally, the clearance groove 145b extends circumferentially away from the front end portion 146a of the protrusion from the allowable groove 145a. Figures 5 to 7 A recessed groove (to the right of center). This clearance groove 145b allows the movement limiting protrusion 131 to be located therewith clearance. In addition, a movement limiting groove 145d, which will be described later, is provided on the side of the clearance groove 145b furthest from the allowable groove 145a (the other end side).

[0094] Furthermore, on the end portion of the clearance groove 145b on the side of the allowable groove 145a, there is an R-shaped portion (a corner portion with rounded corners), the radius of which is set to be equal to the radius of the limiting protrusion 131. Here, if the radius of the R-shaped portion is larger than the radius of the limiting protrusion 131, and the limiting protrusion 131 collides with the R-shaped portion, a force is applied that causes the limiting protrusion 131 to move towards its outer diameter. However, by setting the radius of the R-shaped portion to be equal to the radius of the limiting protrusion 131, it is possible to prevent the limiting protrusion 131 from being subjected to a force that causes it to move towards its outer diameter when it collides with the R-shaped portion. It should be noted that the radius of the R-shaped portion can also be set to be smaller than the radius of the limiting protrusion 131.

[0095] Here, the inner wall (designated as the first limiting wall 145b1) on the outer diameter side of the clearance groove 145b is a wall surface used to engage with the limiting protrusion 131 to hold the limiting member 130 in a predetermined position on the limiting member support member 120, and is an arc-shaped wall surface concentric with the central hole 142. In addition, with the limiting protrusion 131 housed in the clearance groove 145b, the outer diameter side of the limiting member 130 is housed in the limiting member housing 123 in a state where it does not protrude further outward than the outer peripheral surface of the limiting member support member 120.

[0096] Here, the circumferential length of the clearance groove 145b is formed to be longer than the length determined by the angle γ described below. That is, if the operation is interrupted during the winding operation, the ratchet 80 can idle in the unwinding direction by a maximum of one revolution divided by the number of teeth (tooth pitch angle). This angle is set as angle γ (not shown). In this case, it is preferable that the rotary locking device 100 also operates with a delay greater than angle γ. Therefore, in the retracted state of the limiting member 130, the circumferential length of the clearance groove 145b into which the limiting protrusion 131 enters is extended to at least angle γ or more. Moreover, it is preferable that the limiting member 130 is held until the retaining plate 140 rotates relative to the limiting member support member 120 at an angle greater than angle γ, and rotates relative to the drive shaft 25 and the limiting member support member 120 in a second rotation direction opposite to the unwinding direction.

[0097] Furthermore, in this embodiment, the clearance groove 145b is sufficiently long relative to the angle γ. If the clearance groove 145b were short, after switching the knob 45 to the neutral position and operating the idler handle 60 to enter idle mode, the rotation locking device 100 would easily operate during the idle operation of quickly pulling the chain C1 in the unwinding direction, thus reducing the convenience of pulling out the chain C1. Therefore, in order to prevent the rotation locking device 100 from immediately operating during the idle operation of manually pulling out the chain C1 after switching the knob 45 to the neutral position and entering idle mode, the length of the clearance groove 145b is sufficiently long relative to the angle γ. This prevents the rotation locking device 100 from operating and entering a rotation-locked state during the idle operation described above.

[0098] Additionally, the return limiting groove 145c is positioned circumferentially away from the allowable groove 145a. Figures 5 to 7A recessed groove (upward from the center). The limiting protrusion 131 can be positioned in the return limiting groove 145c with clearance. However, a second limiting wall 145c1 is provided in the return limiting groove 145c. The second limiting wall 145c1 engages with the limiting protrusion 131, thereby maintaining the outer diameter side of the limiting member 130 more prominent than the outer peripheral surface of the limiting member support member 120. That is, the second limiting wall 145c1 is used to limit the wall surface of the limiting member 130 to be housed in the limiting member housing portion 123.

[0099] Furthermore, the second limiting wall 145c1 is inclined in a manner that gradually approaches the inner wall 145a1 as it moves toward the inner diameter side, and it contacts the retaining protrusion 146. Therefore, even when the limiting member 130 slides from a predetermined position toward the centrifugal direction, after the limiting protrusion 131 passes the front end 146a of the protrusion, the rotational acceleration of the drive shaft 25 in the first rotational direction decreases. By engaging the limiting protrusion 131 with the second limiting wall 145c1, the limiting member 130 also reliably engages with the locking wall 114, and this engagement is maintained during the period when the load in the first rotational direction continues to act on the drive shaft 25. On the other hand, when the limiting protrusion 131 has entered the return limiting groove 145c, by rotating the limiting member support member 120 and the limiting member 130 relative to the retaining plate 140, thereby causing the limiting protrusion 131 to move toward the allowing groove 145a, the engagement between the limiting protrusion 131 and the second limiting wall 145c1 is released. In this way, the limiting member 130 can move toward the inner diameter side of the limiting member receiving portion 123.

[0100] Furthermore, the movement limiting groove 145d is a groove into which the limiting protrusion 131 installed on the limiting member 130 enters when the limiting member support member 120 and the retaining plate 140 are rotated at high speed in the rolling direction. A third limiting wall 145d1 and a reset guide wall 145d2 are provided in the movement limiting groove 145d.

[0101] The third limiting wall 145d1 is the wall surface that the limiting protrusion 131 collides with. That is, the third limiting wall 145d1 restricts the retaining plate 140 from moving relative to the limiting member 130 by abutting against the limiting protrusion 131 of the limiting member 130 that has moved into the moving limiting groove 145d. Figures 5 to 7The wall surface rotates clockwise. Specifically, for example, with goods hanging on the lower hook (not shown), by forcefully pulling the slack chain C1 on the side opposite to the lower hook, the load pulley 20 around the chain C1 rotates in the winding direction. Furthermore, when the drive shaft 25 and the limiting member support member 120 rotate at high speed as a unit via the reduction gear 30, the retaining plate 140 also rotates at high speed. At this time, the limiting member 130 moves towards the outer diameter side due to centrifugal force, causing the limiting protrusion 131 to enter the movement limiting groove 145d.

[0102] In this state, if the slack in chain C1 is eliminated, the rotation of drive shaft 25 and limiting member support 120 stops abruptly along with load pulley 20. At this time, even if retaining plate 140 wants to rotate in the rolling direction due to inertia, the limiting protrusion 131 abuts against the third limiting wall 145d1, thereby preventing retaining plate 140 from rotating due to inertia.

[0103] Therefore, the third limiting wall 145d1 is configured such that even when pressed by the limiting protrusion 131, the limiting protrusion 131 will not move towards the inner diameter side. For example, a form in which the third limiting wall 145d1 is formed radially can be cited as an example. However, the shape of the third limiting wall 145d1 is not limited to this shape; for example, the third limiting wall 145d1 can be formed such that... Figure 5 The shape of the pocket portion, which is slightly concave to the left (counterclockwise side), can also be shaped to tilt to the left (counterclockwise side) as it moves radially forward.

[0104] Furthermore, the reset guide wall 145d2, like the third limiting wall 145d1 described above, is a wall surface for sliding the limiting protrusion 131. It prevents the limiting member 130 from engaging with the limiting member locking member 110 and returns the limiting member 130 to its designated storage position on the inner diameter side. Specifically, the reset guide wall 145d2 is designed to allow the limiting protrusion 131 to slide as it moves. Figures 5 to 7 The wall surface is inclined to the right (clockwise) and toward the radial center. Therefore, the limiting member 130 can be reset to the storage position of the limiting member storage part 123 by using the reset guide wall 145d2.

[0105] The reset of the aforementioned limiting member 130 is explained in detail below.

[0106] When the locking protrusion 143 of the retaining plate 140 is in a position where it abuts against the side of the limiting member locking member 110, and the member is rotating at a specified high speed, the limiting member 130 moves due to centrifugal force, and the limiting protrusion 131 moves into the movement limiting groove 145d. Considering this state, when the rotation of the drive shaft 25 and the limiting member support member 120 decelerates and stops, before deceleration, the tension of the force spring 151 acts between the limiting member support member 120 and the retaining plate 140; therefore, in... Figures 5 to 7 In the middle, the retaining plate 140 is intended to rotate to the left (counterclockwise) relative to the limiting member support member 120 and the limiting member 130, but this rotation is limited by the contact between the limiting member locking member 110 and the locking protrusion 143. If deceleration begins during high-speed rotation in the rolling direction, then as Figure 11 As shown, the retaining plate 140 rotates in the rolling direction relative to the limiting member support member 120 and the limiting member 130 against the force of the applying spring 151 until it abuts against the third limiting wall 145d1. From this state until the deceleration ends and the device stops, the limiting protrusion 131 slides along the reset guide wall 145d2 due to the force of the applying spring 151, and as the reset guide wall 145d2 tilts, the limiting member 130 is pushed back towards a predetermined storage position. When the magnet M1 approaches the bottom surface 123b of the limiting member storage portion 123 after sliding a predetermined distance, the limiting member 130 is reset to the storage position by the magnetic force between the magnet M1 and the bottom surface 123b.

[0107] Furthermore, even within the movement limiting groove 145d, where the limiting protrusion 131 is located radially outward, the outer peripheral surface 132 of the limiting member 130 is housed within the limiting member housing 123 in a state where it does not protrude further outward than the outer peripheral surface of the limiting member support member 120. In this state, the limiting member 130 will not collide with the locking wall 114, and the limiting member support member 120, the limiting member 130, and the retaining plate 140 can rotate as a whole.

[0108] Furthermore, by assembling the limiting member component 130, the two retaining plates 140, and the force application unit 150 onto the aforementioned limiting member support component 120, the connecting member R1 (refer to...) Figure 4Two retaining plates 140 are connected at a predetermined interval, and the limiting protrusion 131 is restricted by the inner wall of the guide groove 145, thus holding the limiting member 130 in a predetermined position in the limiting member storage portion 123 of the limiting member support member 120, thereby forming a modular unit. This modular design allows for easy and reliable assembly to the drive shaft 25, as well as disassembly or replacement during maintenance. In particular, the operation of the modular unit can be checked or adjusted before assembly to the lever hoist 10 (winch). Furthermore, even under a large load on the limiting member 130, the limiting member 130 can be reliably held in the limiting member storage portion 123 of the limiting member support member 120 by a pair of retaining plates 140.

[0109] In this embodiment, the connecting member R1 is composed of a rivet and a collar (spacer). That is, a collar is arranged between a pair of retaining plates 140, and the rivet is inserted into the hole 141 formed in the retaining plate 140 and the collar. Then, by plastically deforming the other end of the rivet, the pair of retaining plates 140 are connected in a state that maintains a predetermined interval.

[0110] Next, the force-applying unit 150 will be described. For example... Figure 3 and Figure 4 As shown, the force-applying unit 150 includes a force-applying spring 151, a fixed pin 152 at one end, and a connecting member R1 corresponding to the fixed pin at the other end. In this embodiment, the force-applying spring 151 is a tension spring. The force-applying unit 150 may include a tension spring, but may also include a compression spring or a torsion spring, as long as force is applied to cause the retaining plate 140 to move relative to the limiting member support member 120. Figure 3 A structure that rotates in one counterclockwise direction (unwinding direction; first rotation direction) is sufficient.

[0111] Furthermore, as described above, the one-end mounting pin 152 is installed by inserting it into the insertion hole 124 of the limiting member support member 120. The insertion hole 124 is a threaded hole, and installation is achieved by screwing the male threaded portion of the one-end mounting pin 152 into it. Additionally, one end of the force-applying spring 161 is engaged with this one-end mounting pin 152. Furthermore, the other end mounting pin also utilizes the connecting member R1. That is, the other end of the force-applying spring 151 is engaged with the connecting member R1, which is inserted into the hole 141.

[0112] Here, the point of action of the force-applying spring 151, which is attached to the pin 152 at one end, and the point of action of the force-applying spring 151, which is attached to the connecting member R1 at the other end, differ from the rotation center by a predetermined angle θ. Therefore, the force-applying spring 151 applies force in a manner that decreases this angle θ.

[0113] <Regarding its function>

[0114] In the rotary locking (cargo falling prevention) device 100 with the above structure, consider the following situation: during the winding operation of the lever hoist 10, if the braking device 70 is damaged, the drive shaft 25 will start to rotate rapidly in the unwinding direction under the tension applied to the chain C1 by the hanging load, etc.

[0115] Figure 8 It means Figure 1 The diagram shows the structure near the rotary locking (cargo drop prevention) device 100 in the lever hoist 10, and is a perspective view showing the positional relationship of each part of the rotary locking (cargo drop prevention) device 100 before operation. Additionally, Figure 9 It is a perspective representation from Figure 8 The diagram shows the positional relationships of various parts in a state where the retaining plate 140 rotates relative to the limiting member support member 120 and the retaining plate 140, thereby allowing the groove 145a to reach the position of the limiting protrusion 131. Additionally, Figure 10 It is a perspective representation from Figure 9 The diagram shows the positional relationship of various parts in the state shown, where the limiting member 130 protrudes to the outer diameter side and the limiting protrusion 131 is located in the return limiting groove 145c.

[0116] Initially, if braking force is lost while the vehicle is carrying cargo, the drive shaft 25 and the limiting member support member 120, together with the limiting member 130, will... Figure 8 The rotational speed increases sharply in a counterclockwise direction (unwinding direction). At this time, with the limiting protrusion 131 of the limiting member 130 located at the very end of the clearance groove 145b (the end away from the allowable groove 145a), the force of the force spring 151 serves to make the retaining plate 140 follow the rotation of the limiting member 130. However, when the inertial force on the retaining plate 140 exceeds the force of the force spring 151, the limiting protrusion 131 moves away from the end of the movement restriction groove 145d of the clearance groove 145b in the form that the retaining plate 140 is left in. Furthermore, when the drive shaft 25 accelerates in the direction of the movement limiting protrusion 131 moving away from the movement limiting groove 145d side end of the clearance groove 145b (unable to follow), together with the movement limiting support member 120 and the movement limiting member 130, the force spring 151 extends due to the inertial force acting on the retaining plate 140, and the movement limiting protrusion 131 of the movement limiting member 130 moves toward the allowable groove 145a within the clearance groove 145b.

[0117] Furthermore, even if the limiting member 130 is about to protrude to the outer diameter side due to the centrifugal force generated by the rotation of the limiting member support member 120 and the limiting member 130, the limiting protrusion 131 is restricted by the first limiting wall 145b1 before it reaches the allowable groove 145a, thereby limiting the protrusion of the limiting member 130 to the outer diameter side.

[0118] Furthermore, when the limiting protrusion 131 moves relative to the clearance groove 145b Figure 9 When in the indicated position, the limiting member 130 can protrude outwards. That is, the limiting member 130, having released the engagement (holding) state between the limiting protrusion 131 and the first limiting wall 145b1, protrudes outwards from the limiting member receiving portion 123 under the action of centrifugal force. However, the amount of protrusion outwards is within the range up to the outermost circumference of the guide groove 145. On the other hand, even if the limiting member 130 slides in the centrifugal direction from a predetermined position, after the limiting protrusion 131 has passed the front end portion 146a of the protrusion, the rotational acceleration of the drive shaft 25 in the first rotational direction decreases, and under the influence of the force of the force-applying spring 151, the limiting protrusion 131 will be pressed by the second limiting wall 145c1. Through this pressing, the limiting member 130 protrudes to a position reliably engaged with the locking wall 114, and this engagement is maintained while the load in the first rotational direction continues to act on the drive shaft 25.

[0119] Furthermore, if the limiting member 130 protruding from the limiting member storage section 123 continues to rotate in a counterclockwise direction (unwinding direction), then as Figure 10 As shown, the limiting member 130 collides with the locking wall 114 of the limiting member locking member 110. As a result, the rotation of the limiting member support member 120 and the drive shaft 25 in a rotational direction (unwinding direction) is stopped, thereby stopping the falling of the goods.

[0120] Furthermore, after the limiting member 130 collides with the locking wall 114, the limiting protrusion 131 enters the return limiting groove 145c. Thus, after the drive shaft 25 stops, the limiting protrusion 131 receives a counter-clockwise force from the second limiting wall 145c1 through the force of the force spring 151, thereby maintaining the state of the limiting protrusion 131 entering the return limiting groove 145c. At this time, even if the limiting member 130 accidentally attempts to return to the limiting member storage section 123, the engagement of the limiting protrusion 131 with the second limiting wall 145c1 restricts the returning of the limiting member 130 to the limiting member storage section 123. Therefore, the rotation of the drive shaft 25 is stopped, preventing the goods from falling again.

[0121] Next, with the braking device 70 operating normally, consider the idle mode, where the chain C1 can be manually pulled and extended in the unwinding direction. The lever hoist 10 has this idle function to allow adjustment of the chain C1 length when the hook is attached to an object. Specifically, it has the function of releasing the brake via the threaded member 35 of the braking device 70 through the action of an idle spring (not shown). In idle mode, the chain C1 length can be adjusted at a faster speed than when operating via the lever 50. When switching to idle mode in the lever hoist, there are the following methods: an automatic idle mode where switching can be performed simply by setting the switching knob 45 to the neutral position under no-load conditions; and... Figure 1 and Figure 2 As shown in the lever hoist 10, after operating the switching knob 45 to the neutral position, a predetermined operation is performed on the idler handle 60 to switch to the idler mode. In this embodiment, the structure in which the switching knob 45 is operated to the neutral position and a predetermined operation is performed on the idler handle 60 to switch to the idler mode is formed, and its detailed description is omitted here.

[0122] In this idling mode, the braking force of the braking device 70 is temporarily inactive. However, for safety reasons, it becomes a mechanism where the braking device 70 activates when a specified tension is applied to the chain C1 in the unwinding direction, thereby stopping the rotation of the drive shaft 25. On the other hand, since the braking device 70 with ratchet 80 used in many lever hoists, such as the lever hoist 10, does not activate in the winding direction, the length of the chain C1 can be adjusted at a faster speed than when winding using the operating lever 50, even without switching to idling mode. In this situation, the rotation locking (cargo drop prevention) device 100 also operates as inconspicuously as possible in the winding direction (another rotation direction), resulting in good operability.

[0123] However, the length adjustment of chain C1 includes not only the adjustment of feeding chain C1 in the unwinding direction, but also the adjustment of the winding direction of the slack chain C1. As mentioned above, in the unwinding direction, the adjustment is made after switching to the idle mode, but if chain C1 is pulled with a force greater than the specified tension, the braking device 70 is activated. On the other hand, in the winding direction adjustment, the unloaded side of chain C1 is pulled by the operator. In this case, the load pulley 20 rotates in the winding direction, and the drive shaft 25, the limiting member support member 120, and the limiting member 130 also rotate in the winding direction. At this time, the inertial force acting on the retaining plate 140 acts in the direction that presses the limiting protrusion 131 into the side end of the movement limiting groove 145d in the clearance groove 145b. In this state, even if the speed of the pulling chain C1 in the winding direction increases, thereby gradually increasing the centrifugal force acting on the limiting member 130, the limiting member 130 will not lock with the limiting member locking member 110 when the limiting protrusion 131 of the limiting member 130 is located in the clearance groove 145b, including the movement limiting groove 145d. Therefore, the rotation locking of the rotation locking device 100 will not function. At speeds below the specified limit, the limiting member 130 will not protrude radially outwards due to the holding force generated by the magnetic force between the magnet M1 and the bottom surface 123b of the limiting member receiving portion 123. Therefore, at speeds below the specified limit, the limiting protrusion 131 will not enter the movement limiting groove 145d.

[0124] However, when the specified rotational speed is exceeded, the centrifugal force acting on the limiting member 130 becomes greater than the holding force generated by the magnetic force between the magnet M1 and the bottom surface 123b of the limiting member receiving portion 123. Therefore, the limiting member 130 moves outward, and the limiting protrusion 131 enters the movement limiting groove 145d.

[0125] exist Figure 11 and Figure 12 In the shown configuration, the limiting protrusion 131 is located at the outermost diameter side of the movement limiting groove 145d and abuts against the third limiting wall 145d1. Furthermore, in this… Figure 11 In the state shown, the outer peripheral surface 132 of the limiting member 130 is located radially at the same or lower position as the outer peripheral surface of the limiting member support member 120.

[0126] Here, when the chain C1 is released, the chain C1 between the cargo and the lever hoist 10 becomes taut. However, if the cargo is too heavy to be lifted easily, the chain C1 cannot be wound up, causing the rotation of the drive shaft 25 and the limiting member support 120 (limiting member 130) to stop abruptly. However, the retaining plate 140, due to inertia, attempts to rotate in the winding direction, but this is prevented by... Figure 11 and Figure 12As shown, the limiting protrusion 131 abuts (collides) with the third limiting wall 145d1, thereby preventing the retaining plate 140 from rotating due to inertia. Additionally, Figure 11 This is a perspective view showing the movement-limiting protrusion 131 entering the movement-limiting groove 145d, compared to... Figure 8 The diagram shows the positional relationship of various parts in the state shown, where the retaining plate 140 is slightly rotated relative to the rolling direction, so that the limiting protrusion 131 abuts against the third limiting wall 145d1.

[0127] Therefore, it is possible to prevent the limiting protrusion 131 from moving into the allowable groove 145a within the clearance groove 145b. Therefore, it is possible to prevent the following situation: that is, even when the limiting protrusion 131 moves towards the outer diameter side within the allowable groove 145a, although it is in the rolled-up state, the limiting member 130 protrudes further towards the outer diameter side than the outer peripheral surface of the limiting member support member 120.

[0128] Furthermore, when rotation in the rolling direction stops, the limiting member 130 returns to its retracted position in the limiting member storage portion 123. That is, the tension of the force-applying spring 151 acts between the limiting member support member 120 and the retaining plate 140. Therefore, in Figure 11 and Figure 12 In this case, the limiting member support member 120 and the limiting member 130 attempt to rotate to the right (clockwise) relative to the retaining plate 140. Therefore, as Figure 13 As shown, the limiting protrusion 131 slides along the reset guide wall 145d2 under the tension of the force-applying spring 151. Then, when the magnet M1 approaches the bottom surface 123b of the limiting member storage part 123 after sliding a predetermined distance, the magnetic force between the magnet M1 and the bottom surface 123b increases. Under the action of this increased magnetic force, the limiting member 130 resets to the storage position.

[0129] Furthermore, even when the limiting member 130 is returned to its retracted position, the tension of the force-applying spring 151 continues to act between the limiting member support member 120 and the retaining plate 140. Under this tension, the locking protrusion 143 abuts against the side of the wide plate portion 120b of the limiting member support member 120. Therefore, it is possible to prevent the limiting member 130 from being pressed against the side wall 123a of the limiting member support member 120 when a force is applied to the limiting protrusion 131 toward the clockwise end of the clearance groove portion 145b. Furthermore, since the limiting member 130 is attracted and held on the bottom surface 123b of the limiting member storage portion 123 by the magnetic force of the magnet M1, even if the holding plate rotates in the rolling direction relative to the limiting member support member and the limiting protrusion 131 is located in the allowable groove portion 145a, as long as the force exceeding the attraction force generated by the magnetic force does not work, the limiting member 130 is also stored in the predetermined position of the limiting member storage portion, so the rotation locking device 100 will not work.

[0130] Next, consider the scenario where the operator pulls chain C1 in the unwinding direction. In this case, the load pulley 20 rotates in the unwinding direction, and the drive shaft 25, the limiting member support 120, and the limiting member 130 also rotate in the unwinding direction. At this time, the following situation may occur: due to the accelerated rotation of the limiting member support 120 and the limiting member 130, the retaining plate 140 rotates relative to the force of the applied spring 151 in a way that leaves it in place, causing the limiting protrusion 131 to move away from the very end of the clearance groove 145b (the end furthest from the allowable groove 145a). In this case, if the clearance groove 145b is short, the limiting protrusion 131 can more easily reach the allowable groove 145a. Afterward, the limiting member 130 protrudes outward, resulting in a locked state where the locking wall 114 collides with the limiting member 130. In this situation, the operator's pulling of chain C1 in the unwinding direction is interrupted, requiring the unlocking state to be released, thus reducing workability.

[0131] However, in this embodiment, the length of the clearance groove 145b is sufficiently long compared to the aforementioned angle γ, and is set such that during rotational acceleration to the extent that the operator pulls the chain C1 in the unwinding direction, even if the limiting protrusion 131 moves slightly within the clearance groove 145b, it cannot reach the length of the allowable groove 145a. Therefore, the operator's work of pulling the chain C1 in the unwinding direction will not be interrupted. The length of the clearance groove 145b is set such that when the drive shaft 25 rotates rapidly in the unwinding direction in the idle mode, the braking device 70, which is temporarily released in the idle mode, brakes the rotation of the drive shaft 25 before the rotation locking device 100.

[0132] <Regarding the effects>

[0133] The rotation locking (cargo falling prevention) device 100 with the above structure includes: a limiting member support member 120, which is mounted on the drive shaft 25 (shaft-shaped member) and rotates integrally with the drive shaft 25 (shaft-shaped member); a limiting member 130, which is supported on the limiting member support member 120 in a state that can slide outward from the axial side of the drive shaft 25 (shaft-shaped member); a retaining plate 140, which is provided in the shape of a disc and is configured to rotate relative to the limiting member support member 120, and holds the limiting member 130 in a predetermined position on the limiting member support member 120; a force-applying spring 151 (force-applying means), by applying force from the force-applying spring 151, causing the retaining plate 140 to be oriented relative to the limiting member support member 120 in a first rotation direction as a rotation direction; and a limiting member locking member 110 (limiting member locking means), which stops the rotation of the drive shaft 25 (shaft-shaped member) by engaging with the limiting member 130.

[0134] Additionally, the limiting member 130 has a limiting protrusion 131 protruding toward the retaining plate 140, and the retaining plate 140 has a guide groove 145 that engages with the limiting protrusion 131 and holds the limiting member 130 at a predetermined radial position on the limiting member support member 120. The guide groove 145 has a first limiting wall 145b1 and a second limiting wall 145c1, wherein the first limiting wall 145b1 engages with the limiting member 130 at a predetermined radial position, and the first limiting wall 145b1 is formed by an arc concentric with the drive shaft 25 (shaft-shaped member), and the second limiting wall 145c1 engages with the limiting member 130 at a position where the limiting member 130 protrudes outward from the predetermined radial position, and the second limiting wall 145c1 is provided on one side of the guide groove 145 in the circumferential direction.

[0135] Furthermore, when the drive shaft 25 (shaft-shaped member) accelerates its rotation in the first rotational direction, the limiting member support member 120 and the retaining plate 140 rotate relative to each other against the force of the force-applying spring 151 (force-applying means). This releases the locking between the limiting protrusion 131 and the first limiting wall 145b1. The limiting member 130 then protrudes from a predetermined position toward a position where it engages with the limiting member locking member 110 (limiting member locking means), thereby stopping the rotation of the drive shaft 25 (shaft-shaped member). Additionally, a third limiting wall 145d1 is provided on the other side of the guide groove 145 in the circumferential direction. This third limiting wall 145d1 engages with the limiting member 130 at a position where it protrudes from a predetermined radial position toward the outer diameter side, thereby preventing the retaining plate 140 from rotating relative to the limiting member support member 120 in a second rotational direction opposite to the first rotational direction. Moreover, when the limiting protrusion 131 engages with the third limiting wall 145d1, it is located at a position where the limiting member 130 and the limiting member locking member 110 (limiting member locking means) are not locked.

[0136] According to this structure, when the operator pulls the slack chain C1 at high speed in the winding direction, under the centrifugal force acting on the limiting member 130, the limiting member 130 protrudes outward, releasing the slack of the chain C1. This causes the drive shaft 25 and the limiting member support member 120 (limiting member 130) to stop abruptly, and the retaining plate 140, due to inertia, attempts to rotate in the winding direction. However, the limiting protrusion 131 abuts (collides) with the third limiting wall 145d1, preventing the retaining plate 140 from rotating due to inertia. Therefore, it is possible to prevent the limiting protrusion 131 from moving in the second rotation direction within the guide groove 145. In addition, when the limiting protrusion 131 engages with the third limiting wall 145d1, it is located at the part where the limiting member 130 and the limiting member locking member 110 (limiting member locking means) are not locked. Therefore, it can prevent the limiting member 130 from protruding further outward than the outer diameter side compared with the outer peripheral surface of the limiting member support member 120, even when it is in the rolled-up state.

[0137] Therefore, it is possible to prevent the rotation locking device 100 from accidentally operating even though the goods have not actually fallen (movement in the rolling direction), thereby preventing the drive shaft 25 (shaft member) from rotating. This also prevents the trouble of restoring the rotation locking device 100.

[0138] Furthermore, if the drive shaft 25 (shaft-shaped member) rotates in one direction beyond a predetermined acceleration in the unwinding direction, the rotational locking (cargo falling prevention) device 100 operates, thereby stopping the rotation. Further, it can be configured such that when the drive shaft 25 (shaft-shaped member) accelerates in a first rotational direction, the rotational locking (cargo falling prevention) device 100 operates at a lower speed than when rotating in the other direction, through the combined effect of this acceleration and rotational speed. Additionally, in drive devices such as winches or lifting devices where the load acts only in one direction, even if the braking device 70 malfunctions, the rotation of the rotating member used for winding or lifting can be stopped immediately, thereby preventing accidents caused by cargo falling.

[0139] In addition, in this embodiment, a reset guide wall 145d2 is provided at a position on the other side of the circumference relative to the third limiting wall 145d1, for returning the limiting member 130 to a predetermined position on the axial side. The reset guide wall 145d2 is inclined toward the radial inner diameter side as it moves from one side of the circumference to the other.

[0140] With this configuration, the limiting member 130 can be easily reset to the designated position (return position) of the limiting member support member 120. That is, the tension of the force-applying spring 151 (force-applying means) acts between the limiting member support member 120 and the retaining plate 140. Therefore, in Figures 5 to 7 In this configuration, the limiting member support member 120 and the limiting member 130 are to rotate to the right (clockwise) relative to the retaining plate 140. Therefore, by sliding the limiting protrusion 131 along the reset guide wall 145d2, the limiting member 130 can be moved toward a predetermined position (return position) of the limiting member support member 120. Thus, the limiting member 130 can be easily reset to the predetermined position (return position) of the limiting member support member 120.

[0141] Furthermore, in this embodiment, the third limiting wall 145d1 and the reset guide wall 145d2 are provided on the inner wall of the movement limiting groove 145d. Therefore, when processing the retaining plate 140, the third limiting wall 145d1 and the reset guide wall 145d2 can be formed simultaneously, for example, by stamping, thereby simplifying the processing steps.

[0142] Furthermore, in this embodiment, the limiting member support member 120 is made of a soft magnetic material, and a magnet M1 is installed on the radial inner diameter side of the limiting member 130. Therefore, the magnetic force of the magnet M1 can be used to help the limiting member 130 return to a predetermined position (storage position).

[0143] In addition, in this embodiment, a locking protrusion 143 (protruding means) is provided on the retaining plate 140, protruding from the surface or back of the retaining plate 140. The locking protrusion 143 (protruding means) is positioned such that when the retaining plate 140 is oriented toward the first rotation direction by the force applied by the force spring 151 (force applying means), it abuts against the side surface 120b1 of the limiting member support member 120 before or at the same time as the limiting protrusion 131 and the end of the guide groove 145 on the opposite side of the first rotation direction come into contact.

[0144] Therefore, by abutting the locking protrusion 143 (protruding means) against the side surface 120b1 of the limiting member support member 120, continuous force can be prevented from acting on the limiting protrusion 131. Furthermore, it can prevent the limiting member 130 from being pressed against the side wall inside the limiting member receiving portion 123. Therefore, it can prevent the limiting member 130 from being hindered from returning to its designated position (receiving position) due to friction between the limiting member 130 and the side wall inside the limiting member receiving portion 123.

[0145] In addition, in this embodiment, a spring bracket protrusion 144 is provided on the retaining plate 140. The spring bracket protrusion 144 is formed by bending a part of the retaining plate 140 and is positioned closer to the outer diameter side of the retaining plate 140 than the force-applying spring 151 (force-applying means). The spring bracket protrusion 144 prevents the force-applying spring 151 (force-applying means) from falling off to the outer diameter side due to the centrifugal force when the retaining plate 140 rotates.

[0146] Thus, by arranging the spring support protrusion 144 at a position closer to the outer diameter side of the retaining plate 140B than the force-applying spring 151 (force-applying means), it is possible to prevent the force-applying spring 151 from falling off to the outer diameter side due to centrifugal force when the retaining plate 140 rotates.

[0147] <Variation Example>

[0148] The various embodiments of the present invention have been described above, but various modifications can be made to the present invention. These modifications will be described below.

[0149] In the above embodiments, the rotary locking (cargo falling prevention) device 100 was described as being applied to the lever hoist 10. However, the rotary locking (cargo falling prevention) device can also be applied to winches other than lever hoists, such as chain hoists, or to lifting devices with a fixed load direction similar to that of the lifting device.

[0150] Furthermore, in the above embodiment, the case where the magnet M1 is mounted on the bottom surface 130a of the limiting member 130 has been described. However, the magnet may also be mounted on the bottom surface 123b of the limiting member storage portion 123, or on both the bottom surface 130a of the limiting member 130 and the bottom surface 123b of the limiting member storage portion 123.

[0151] Figure 14 An example of this structure is shown in the figure. Figure 14 In this design, a recess (not shown) is provided on the bottom surface 130a side of the limiting member 130, and a magnet M1 is disposed within this recess. Furthermore, a recess (not shown) is also provided on the bottom surface 123b side of the limiting member support member 120, and a magnet M2 is disposed within this recess. At this time, the opposing magnetic poles of magnets M1 and M2 are different, so that magnets M1 and M2 attract each other through magnetic force.

[0152] Here, as Figure 14 The attraction force shown in the diagram where magnets M1 and M2 are in contact and attracted (i.e., the distance between magnets M1 and M2 is 0) is similar to that shown in the diagram. Figure 5 The attraction forces of the magnet M1 and the bottom surface 123b of the limiting member support member 120 made of ferrous metal shown are equal when they are in contact and attracted (i.e., the distance between the magnet M1 and the bottom surface 123b is 0).

[0153] Here, for example Figure 15 The attraction force of magnets M1 and M2 facing each other with a distance Y as shown in Figure (A) is compared with the attraction force of magnet M1 facing each other with the bottom surface 123b of the limiting support member 120 separated by the same distance Y. In this case, since the attraction force of the magnet is inversely proportional to the square of the distance, the attraction force of magnets M1 and M2 facing each other with a distance Y is about four times that of magnet M1 facing each other with the bottom surface 123b of the limiting support member 120 separated by the same distance Y. In other words, compared with... Figure 15 As shown in (A), the attraction force is equal when the magnet M1 and the bottom surface 123b of the limiting member support member 120 are separated by a distance Y and are facing each other, such as... Figure 15 As shown in (B), the attraction force when the magnet M1 is placed opposite the bottom surface 123b of the limiting member support member 120 at a distance of Y / 2.

[0154] As described above, magnets M1 and M2, which exert magnetic force in a mutually attractive direction, are respectively installed on the radial inner diameter side of the limiting member 130 and the opposite portion of the limiting member support member 120. Therefore, as... Figure 5 Compared to the structure shown where the magnet M1 and the bottom surface 123b of the limiting member support member 120 are opposite each other, the attractive force generated by the magnetic force when the magnets M1 and M2 are separated can be enhanced. Therefore, when the limiting member 130 protrudes to the outer diameter side, even if the frictional resistance caused by foreign objects reaches a certain level, the limiting member 130 can be easily reset to the specified position (storage position).

[0155] Additionally, as from Figure 6 or Figure 7 As is clearly understood from the above, in the retaining plate 140, the radial dimension of the movement limiting groove 145d is set to be smaller than the radial dimension of the allowable groove 145a. Therefore, when the limiting member 130 is located in the allowable groove 145a, the amount of protrusion of the limiting member 130 toward the outer diameter side is smaller compared to the case where the limiting member 130 is located in the movement limiting groove 145d. Therefore, when the structure of arranging magnets M1 and M2 as described above is adopted, compared to the structure where magnet M1 and the bottom surface 123b of the limiting member support member 120 are opposite each other, the limiting member 130 can be easily reset to the specified position (return position).

[0156] Furthermore, an example is shown where the rotational locking (cargo falling prevention) device 100 is disposed on the drive shaft of the winch, but its installation position is not limited to the drive shaft. For example, the rotational locking (cargo falling prevention) device 100 can be disposed on a shaft-like member that rotates integrally with the rotating member being targeted, such as the shaft of a load pulley or drum. In this way, even if the deceleration mechanism or the like is damaged, cargo falling can be prevented.

[0157] In addition, although the illustration is omitted, a guide groove may be provided on the side of the limiting member 130, and a guide pin that engages with the guide groove may be provided on the side of the retaining plate 140.

[0158] Alternatively, it is preferable to use two retaining plates 140 to clamp the limiting member support member 120, but it can also be configured such that only one retaining plate 140 is adjacent to the limiting member support member 120.

[0159] Furthermore, by bending a portion of the retaining plate 140B to provide a locking protrusion 143 corresponding to the protruding means, it abuts against the side 120b1 of the limiting member support member 120, thereby limiting the rotation of the retaining plate 140 caused by the force applied by the force unit 160. However, other components mounted on the retaining plate 140, such as a connecting member R1 like a rivet, may also be used as protruding means.

[0160] In addition, in order to pull the limiting member 130 back to the position in contact with the bottom surface 123b when the limiting protrusion 131 is in the moving limiting groove 145d, a magnet M1 is provided. However, it can also be configured such that the gently inclined portion of the reset guide wall is made longer and pulled back by the force of the force application unit 160.

[0161] In addition, the movement limiting groove 145d with the third limiting wall 145d1 is provided on the end of the clearance groove on the other side, but is not limited to the end, it can also be provided in the middle, and there can be multiple of them.

[0162] (Symbol Explanation)

[0163] 10…Lever hoist, 11, 12…Frame, 12a…Through hole, 12b…Shaft hole, 13…Housing, 14…Brake cover, 14a…Flange, 14a1…Through hole, 15…Locking cover, 15a…Upright part, 15b…Opposing surface, 15b1…Through hole, 20…Load pulley, 20a…Through hole, 21…Load gear, 25…Drive shaft (corresponding to shaft-shaped member), 26…Male thread, 27…Pinary gear, 30…Reduction gear, 31…Large diameter gear, 32…Small diameter gear, 34…Gearbox, 35…Female thread member, 36…Female thread, 37…Switching gear, 40… 45… Switching pawl, 50… Switching knob, 55… Operating lever, 56… Cam assembly, 60… Idle handle, 70… Braking device, 71… Brake support, 71a… Flange, 71b… Hollow bushing, 72a, 72b… Brake plate, 80… Ratchet (corresponding to a part of the ratchet mechanism), 83… Ratchet tooth, 90… Pawl assembly (corresponding to a part of the ratchet mechanism), 91… Pawl shaft, 92… Bushing, 93… Torsion spring, 93a… Coil, 100… Rotary locking (cargo drop prevention) device, 110… Limiting member locking member (corresponding to the limiting member locking means), 111… Mounting hole, 111a… 112…Inner wall surface, 113…Inner protrusion, 114…Lower portion, 114a…Corner portion, 115…Pawl shaft (corresponding to a part of the ratchet mechanism), 116…Reinforcing rib, 120…Limiting member support member, 120a…Narrow plate portion, 120b…Wide plate portion, 121…Center hole, 122…Bearing sleeve portion, 123…Limiting member storage portion, 123a…Side wall, 123b…Bottom surface, 124…Insertion hole, 125…Storage recess, 126…Anti-disengagement recess, 127…Inclined wall, 130…Limiting member, 130a…Bottom surface, 131…Limiting protrusion, 132…Outer peripheral surface 140…Retaining plate, 141…Hole, 142…Center hole, 143…Catching protrusion, 144…Spring support protrusion, 145…Guide groove, 145a…Allowing groove, 145a1…Inner wall, 145b…Clearance groove, 145b1…First limiting wall, 145c…Return limiting groove, 145c1…Second limiting wall, 146…Retaining protrusion, 146a…Protrusion front end, 150…Force application unit (corresponding to force application means), 151…Force application spring, 152…One-end hanging pin, B1…Support bolt (corresponding to stop member), C1…Chain, R1…Connecting structural member, SP1…Space

Claims

1. A rotary locking device, characterized in that, have: A limiting support member is mounted on a shaft-shaped member and rotates integrally with the shaft-shaped member. A movement-limiting member is supported on the movement-limiting support member in a state that allows it to slide outward from the axial side of the shaft-shaped member. A retaining plate, which is disc-shaped and configured to rotate relative to the limiting member support member, holds the limiting member in a predetermined position on the limiting member support member. The force-applying means, by applying force, causes the retaining plate relative to the limiting member support member to be oriented in a first rotational direction, which is a rotational direction. A limiting component locking means, which stops the rotation of the shaft-shaped component by engaging with the limiting component; The movement-limiting member has a movement-limiting protrusion that protrudes toward the retaining plate. The retaining plate has a guide groove that engages with the limiting protrusion and holds the limiting member at a predetermined position in the radial direction of the limiting member support member. The guide groove has a first limiting wall and a second limiting wall. The first limiting wall engages with the limiting member at a predetermined position in the radial direction and is formed by an arc concentric with the shaft-like member. The second limiting wall engages with the limiting member at a position where it protrudes outward from a predetermined position in the radial direction. The second limiting wall is disposed on one side of the guide groove in the circumferential direction. When the shaft-shaped member accelerates its rotation in the first rotational direction, the limiting member support member and the retaining plate rotate relative to each other against the force of the force-applying means. As a result, when the locking between the limiting protrusion and the first limiting wall is released, the limiting member protrudes from a predetermined position towards a position engaged with the limiting member locking means, thereby stopping the rotation of the shaft-shaped member. A third limiting wall is provided on the other side of the guide groove in the circumferential direction. This third limiting wall engages with the limiting member at a position where it protrudes from a predetermined position in the radial direction toward the outer diameter side, thereby preventing the retaining plate from rotating relative to the limiting member in a second rotation direction opposite to the first rotation direction. When the limiting protrusion engages with the third limiting wall, it is located at a position where the limiting member and the limiting member locking means are not locked.

2. The rotary locking device according to claim 1, characterized in that, At a position further along the circumferential direction than the third limiting wall, a reset guide wall is provided to return the movement-limiting member to a predetermined position on the axial side. The reset guide wall is inclined toward the radial inner diameter side as it moves from one side of the circumferential direction toward the other.

3. The rotary locking device according to claim 2, characterized in that, The third limiting wall and the reset guide wall are disposed on the inner wall of the moving limiting groove.

4. The rotary locking device according to any one of claims 1 to 3, characterized in that, The limiting member support component is made of soft magnetic material, and, A magnet is installed on at least one of the radial inner diameter side of the limiting member and the opposing portion of the limiting member support member, in a direction that attracts each other.

5. The rotary locking device according to claim 4, characterized in that, Magnets that apply magnetic force in the direction of attraction to each other are respectively installed on the radial inner diameter side of the limiting member and the opposing part of the limiting member support member.

6. The rotary locking device according to any one of claims 1 to 5, characterized in that, The retaining plate is provided with protruding means that protrude from the surface or back of the retaining plate. The protruding means is positioned such that, when the retaining plate is oriented toward the first rotation direction by the force applied by the force-applying means, it abuts against the side of the limiting member support member before or at the same time as the ends of the limiting protrusion and the guide groove on the opposite side of the first rotation direction come into contact.

7. The rotary locking device according to any one of claims 1 to 6, characterized in that, The retaining plate is provided with a spring bracket protrusion, which is formed by bending a portion of the retaining plate and is positioned further away from the outer diameter of the retaining plate than the force-applying means. The spring support protrusion prevents the force-applying means from falling off to the outer diameter side due to the centrifugal force when the retaining plate rotates.

8. A winch, characterized in that, have: A load-bearing pulley, supported by an axle on a pair of frames, and with a chain around which the load is lifted. The drive shaft is connected to the load pulley via a reduction gear. A braking device, which is mounted on the drive shaft; as well as The operating lever drives the load pulley to rotate in the winding and unwinding direction. The outer periphery of the drive shaft is provided with a rotary locking device as described in any one of claims 1 to 6. The shaft-shaped component is the drive shaft. The limiting component locking means is installed on the frame.

Images