JP2023049862A - Rotation lock device and hoist - Google Patents

Abstract

To easily release the rotation disabled state of a drive shaft caused by an erroneous operation.SOLUTION: A rotation lock device comprises: a stopper support member 130 that supports a stopper member 140 and rotates integrally with a shaft-like member; a guide groove 154 that includes a first groove and a second groove positioned outside the first groove in the radial direction of the shaft-like member; a holding plate 150 that is rotatable with respect to the stopper support member 130; biasing means 186 for biasing the holding plate 150 with respect to the stopper support member 130 in one direction and inserting and holding a projection 141 of the stopper member 140 in one of the first and second grooves; stopper locking means 110 having a lock wall with which the stopper member 140 collides due to movement of the projection 141 to the second groove when the shaft-like member rotates at a speed exceeding a prescribed speed in one direction; and releasing means for pushing-in the stopper member 140 and moving the projection 141 to the first groove to release a rotation stop of the shaft-like member in one direction.SELECTED DRAWING: Figure 5

Description

The present invention relates to a rotation lock device and a hoist.

BACKGROUND ART Lever hoists are widely used for operations such as lifting loads, pulling loads, or fixing loads with slings or the like (tightening loads). A lever hoist can wind up (rewind) or lower (rewind) a chain by manually operating an operation lever. As a lever hoist, for example, there is one shown in Patent Document 1. The lever hoist shown in Patent Document 1 houses one or more centrifugal force members (31) attached to the drive shaft (10) and the centrifugal force member (31) in addition to a conventional brake mechanism (mechanical brake). It has a housing ring (35). The centrifugal force member (31) rotates together with the drive shaft (10) when the drive shaft (10) rotates, and is pressed against the inner peripheral surface of the housing ring (35) by the centrifugal force exerted by the rotation. This reduces the speed at which the load falls.

Further, as a conventional brake mechanism (mechanical brake), there is one disclosed in Patent Document 2. The brake mechanism shown in Patent Document 2 includes a pressure receiving member (7) non-rotatably attached to a drive shaft (4), a drive member (8) screwed to the drive shaft (4), and a pair of brake plates (10a). , 10b), a ratchet wheel (11) for preventing reverse rotation, and a ratchet pawl (12) mounted on a pawl shaft (15). The ratchet pawl (12) is urged by the spring (13) so that the ratchet pawl (12) is engaged with the locking teeth (11a) of the ratchet wheel (11). The engagement between the ratchet pawl (12) and the locking teeth (11a) of the ratchet wheel (11) prevents the ratchet wheel (11) from reversing, thereby preventing the drive shaft (4) from rotating in the lowering direction. It has become.

DE102015121581A1 Japanese Patent Application Laid-Open No. 2008-230726

By the way, when hoists (lever hoists and chain blocks) are hoisted, a brake mechanism (mechanical brake ), if there is a problem with the meshing of the ratchet wheels and pawl members or if these members are damaged, the brake mechanism will not function properly, and the load sheave that winds up the chain will vigorously rotate in the lowering direction due to the load of the suspended load. start to drop the load.

For example, in the configuration disclosed in Patent Document 1, the centrifugal force member (31) is pressed against the inner peripheral surface of the housing ring (35) by the action of centrifugal force, thereby slowing down the falling speed of the load (that is, the rotational speed of the pinion). However, it does not stop the load from falling. Therefore, a device (hereinafter referred to as a rotation lock device) is required to stop the rotation of the drive shaft by locking the drive shaft, which is rapidly rotated in the lowering direction by the load of the load, when the brake device fails. In order to prevent the load from dropping again, such a rotation lock device cannot easily unlock the drive shaft once it is locked. Further, in the operation using the above-described lever hoist or the like, an operation such as removing the slack of the chain at once is sometimes performed by performing a hoisting operation such as pulling the unloaded side of the chain vigorously. Such unintended operation may unintentionally activate the rotation lock device, rendering the drive shaft non-rotatable. Thus, when the rotation lock device is actuated, there is a problem that it takes time to restore the rotation lock device.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems, and its object is to provide a state in which the drive shaft cannot rotate when the rotation lock device is actuated by an erroneous operation and the drive shaft cannot rotate. It aims at providing the technique which can release easily.

In order to solve the above problems, a rotation lock device of the present invention is a rotation lock device for locking a sudden rotation of a shaft-like member in one direction, and has a projection along the axial direction of the shaft-like member. a stopper member; a stopper supporting member that supports the stopper member in a slidable state outwardly from the axial center side of the shaft-shaped member and rotates integrally with the shaft-shaped member; A first groove portion extending in an arc shape along the circumferential direction, and a second groove portion located outside the first groove portion in the radial direction of the shaft-shaped member at a side end portion of the first groove portion in the one direction. and a holding plate rotatably attached to the stopper support member in a state in which the projection of the stopper member is inserted into the guide groove; and the holding plate is attached to the stopper support member. urging means for urging the stopper member in the one direction to hold the projection of the stopper member in either the first groove portion or the second groove portion of the guide groove; When the shaft-shaped member rotates in the one direction due to excessive acceleration, a change in the relative position of the stopper support member rotating together with the shaft-shaped member with respect to the holding plate, and the stopper member rotating together with the stopper support member. and the centrifugal force causes the projection held in the first groove portion to move to the second groove portion, and the stopper member projecting from the outer peripheral edge of the stopper support member collides with the stopper member. Thus, the stopper locking means having the locking wall for stopping the rotation of the shaft-shaped member in the one direction, and the stopper member projecting outward from the outer peripheral surface of the stopper support member are attached to the shaft-shaped member. releasing means for releasing the stoppage of rotation of the shaft-like member in the one direction by moving the projection of the stopper member inserted into the second groove portion by pushing it toward the shaft center side to the first groove portion; , is characterized by having

The first groove portion has a first wall surface against which the projection of the stopper member abuts due to a centrifugal force acting on the stopper member when the stopper member rotates together with the stopper support member, and the second groove portion has a first wall surface. is a state in which the projection of the stopper member is held in the second groove, and when the holding plate rotates in the one direction due to the biasing force of the biasing means, the It has a second wall surface with which the projection of the stopper member abuts, and in a plane orthogonal to the axial direction, the intersection of the first wall surface and the second wall surface is the outer peripheral surface of the stopper member that is the stopper supporting member. The stopper member is positioned closer to the shaft center side of the shaft-shaped member than the center of the projection of the stopper member when flush with the outer peripheral surface, and the releasing means presses the stopper member toward the shaft center side of the shaft-shaped member. By doing so, in the plane, the center of the protrusion of the stopper member is moved to a position closer to the shaft center of the shaft-like member than the position of the intersection point.

Further, the release means is slidably contacted by the stopper member projecting outward from the outer peripheral surface of the stopper support member when the shaft member is rotated in the other direction opposite to the one direction. a sliding contact surface for moving the stopper member in the axial direction of the shaft-shaped member until the outer peripheral surface of the stopper member is flush with the outer peripheral surface of the stopper support member; and the projection of the stopper member. a pushing portion that pushes the stopper member toward the shaft center side of the shaft-shaped member to a position where the center of the is closer to the shaft center side of the shaft-shaped member than the position of the intersection.

Further, the releasing means is rotatably attached to the stopper engaging means in a state of being biased in a direction away from the holding plate, and the releasing means receives pressure toward the holding plate to move the stopper. The stopper member protruding outward from the outer peripheral surface of the support member is pushed into the axial center side of the shaft-like member.

Further, the hoist of the present invention includes a load sheave which is pivotally supported by a pair of frames and around which a chain for lifting a load is wound; an operation lever for rotating the load sheave in one of a lowering direction corresponding to the one direction and a lowering direction opposite to the lowering direction; and the shaft-shaped member and a ratchet wheel having ratchet teeth on the outer peripheral side, a pawl member that engages with the ratchet teeth, and a pawl shaft that supports rotation of the pawl member, wherein the ratchet teeth and the pawl and a brake device having a ratchet mechanism that permits rotation of the ratchet wheel in the winding-up direction and prohibits rotation in the winding-down direction by engagement with a member.

According to the present invention, when the drive shaft becomes unrotatable, the unrotatable state of the drive shaft can be easily released.

BRIEF DESCRIPTION OF THE DRAWINGS It is a front view which shows an example of a structure of the lever hoist which concerns on this Embodiment. It is a perspective view which shows the structure of the lever hoist shown in FIG. FIG. 2 is a cross-sectional view in the XZ plane showing the configuration of the lever hoist shown in FIG. 1; It is a front view which shows the structure of the rotation lock device which a lever hoist has. FIG. 3 is a perspective view showing an exploded configuration of the rotation lock device; It is a perspective view which shows the structure of the back side of a stopper locking member and an unlocking member. 4 is a plan view showing the structure of a holding plate; FIG. FIG. 10 is a diagram showing the positional relationship between the stopper projection and the tip of the projection of the guide groove provided on the holding plate when the outer peripheral surface of the stopper member matches the outer peripheral surface of the holding plate; FIG. 4 is a perspective view showing the structure of an unlocking member; It is a figure which shows the state which a stopper support member rotates to a lowering direction. FIG. 10 is a diagram showing a state in which the stopper member protrudes from the outer peripheral surface of the holding plate and collides with the locking surface of the stopper locking member; FIG. 10 is a diagram showing a state in which the lock release member is pushed and the push-in projection enters between the holding plates; It is a figure which shows the state which the push-in protrusion has run on the outer peripheral surface of the wide piece part of a stopper support member. FIG. 10 is a diagram showing a state in which the push-in projection pushes the stopper member, and the stopper projection of the stopper member enters the clearance groove portion of the guide groove;

A lever hoist 10, which is an example of a hoist according to an embodiment of the present invention, will be described below with reference to the drawings. In the following description, the X-axis direction is the axial direction of the drive shaft 25, the X1 side is the side to which the free rotation barb 60 is attached, and the X2 side is the opposite side to which the reduction gear 30 is attached. In addition, the Z-axis direction is the vertical direction (suspension direction; hoisting or lowering direction) in the suspended state of the lever hoist 10, the Z1 side is the upper side in the suspended state, and the Z2 side is the lower side in the suspended state. . A direction orthogonal to the X-axis direction and the Z-axis direction is the Y-axis direction, the Y1 side is the right side in FIG. 1, and the Y2 side is the left side in FIG. Further, in the following description, regarding the rotation direction of the load sheave 20, one rotation direction is the lowering direction, and the other rotation direction is the lifting direction. Further, the direction of rotation about the axis connected to the load sheave 20 is based on the direction in which the load sheave 20 is rotated.

<Regarding the overall configuration of the lever hoist>
FIG. 1 is a front view showing an example of the configuration of a lever hoist 10 according to this embodiment. 2 is a perspective view of the lever hoist 10 shown in FIG. 1. FIG. FIG. 3 is a cross-sectional view in the XY plane showing the configuration of the lever hoist 10 shown in FIG.

As shown in FIGS. 1 to 3, between a pair of frames 11 and 12 of the lever hoist 10, a load sheave 20 around which a chain CH is wound is rotatably supported. The load sheave 20 is provided with a load gear 21 that meshes with a small-diameter gear portion 32 of a reduction gear 30, which will be described later, at the end on the X2 side.

Further, the load sheave 20 has an insertion hole 20a that penetrates in the axial direction (X-axis direction), and the drive shaft 25 is inserted through the insertion hole 20a of the load sheave 20. As shown in FIG. A male threaded portion 26 that meshes with a female threaded member 35 constituting a braking device 70 to be described later is provided on the outer peripheral side of the middle of the drive shaft 25 . A pinion gear 27 that meshes with the diameter gear portion 31 is provided. The reduction gear 30 is also integrally provided with a small-diameter gear portion 32 that meshes with the load gear 21 described above. In addition, the drive shaft 25 corresponds to a shaft-shaped member described in the claims.

A casing 13 is attached to the frame 11 to protect drive parts such as the reduction gear 30 and the load gear 21 described above. Further, the male threaded portion 26 described above is engaged 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 mesh with the switching pawl 40 arranged on the operating lever 50 . The switching pawl 40 is, for example, a ratchet pawl provided on one side and one on the other side. to transmit the driving force.

A switching knob 45 is coaxially fixed to the switching claw 40 . The switching knob 45 is operated to select a hoisting position in which driving force is transmitted to the female screw member 35 in the hoisting direction, a hoisting position in which the transmission is in the hoisting direction, or a driving force is transmitted to the female screw member 35. It can be switched to any position, not the neutral position.

In FIG. 1, when the lower side of the switching knob 45 is in a position parallel to the Z2 direction, it is in an idle state in which the chain CH can be pulled out by hand (at this time, the load sheave 20 and the drive shaft 25 also rotate). . This state is the neutral position described above. When the lower side of the switching knob 45 is rotated leftward from the neutral position shown in FIG. As a result, when the operation lever 50 is repeatedly rotated in the R1 direction in FIG. 1 and then returned in the R2 direction in FIG. 1, the switching gear 37 rotates in the hoisting direction but does not rotate in the lowering direction. This state corresponds to the hoisting state of the chain CH, and the position of the switching knob 45 at this time is the hoisting position.

On the other hand, when the lower side of the switching knob 45 is rotated rightward from the neutral position shown in FIG. As a result, when the operation lever 50 is repeatedly rotated in the R3 direction in FIG. 1 and then returned in the R4 direction in FIG. 1, the switching gear 37 rotates in the lowering direction but does not rotate in the raising direction. This state corresponds to the lowering state of the chain CH, and the position of the switching knob 45 at this time is the lowering position.

A cam member 55 is attached to the drive shaft 25 in a non-rotatable state such as spline connection or key connection. Further, a member called an idle bar 60 is attached to the cam member 55 so as to be slidable in the axial direction (X-axis direction) by a predetermined amount. 3, the idle rotation barb 60 is non-rotatably engaged with the cam member 55. However, when the idle rotation barb 60 is slid in the X1 direction, the idle rotation barb 60 is kept constant with respect to the cam member 55. It is rotatable within the range of The free rotation gripper 60 is a substantially cylindrical knob-shaped portion that can rotate together with the drive shaft 25 via the cam member 55, and can be gripped by the operator's hand.

The loose rotation barb 60 is connected to the female screw member 35 by a first torsion spring (not shown), and is further connected to one end of the drive shaft 25 by a second torsion spring (not shown). When the switching knob 45 is in the neutral position, when the idle rotation grip 60 is slid in the X1 direction in FIG. . The first torsion spring attached to the free rotation barb 60 that has rotated by a predetermined amount also rotates in the lowering direction, releasing the biasing force that has urged the female screw member 35 to rotate in the winding up direction until then, and switches to the free rotation mode. . Here, regardless of whether it is in the idle rotation mode or not, when the operator grips the idle rotation gripper 60 and rotates it in the hoisting direction, the rotational force can be transmitted to the drive shaft 25 . Therefore, by rotating the idle rotation gripper 60, it is possible to quickly adjust the length of the chain CH, and to switch to the idle rotation mode by sliding it. Also, in the idle rotation mode, when tension exceeding a specified value acts on the chain CH in the lowering direction, the female screw member 35 rotates in the lowering direction, which is the tightening direction, relative to the drive shaft 25, and the brake device 70 described below rotates relative to the drive shaft 25 in the lowering direction. works.

<Regarding the brake device 70>
As shown in FIG. 3, a brake device 70 is arranged on the drive shaft 25 connected to the load sheave 20 via gears. The brake device 70 includes a brake receiver 71, brake plates 72a and 72b, a ratchet wheel 80, a pawl member 90, a pawl shaft 91, a bushing 92, a female screw member 35, and the like as main components. Also, the ratchet wheel 80, the pawl member 90 and the pawl shaft 91 correspond to the main components of the ratchet mechanism.

The brake receiver 71 has a flange portion 71a and a hollow boss portion 71b. The flange portion 71a is provided with a larger diameter than the hollow boss portion 71b, and is capable of receiving the brake plate 72a.

The hollow boss portion 71b is located closer to the female screw member 35 (X1 side) than the flange portion 71a, and pivotally supports the ratchet wheel 80 via the bush 92. As shown in FIG. The inner peripheral side of the hollow boss portion 71b is engaged with the drive shaft 25 by spline coupling or the like, so that the drive shaft 25 and the brake bearing 71 rotate integrally.

Between the flange portion 71a and the ratchet wheel 80 and between the female screw member 35 and the ratchet wheel 80, brake plates 72a and 72b are pivotally supported by the hollow boss portion 71b, respectively. The brake plates 72a and 72b are, for example, plate-shaped friction materials made of a predetermined friction material, or are arranged on both surfaces of the ratchet wheel 80 by sintering.

When the female screw member 35 is rotated in the hoisting direction, the female screw member 35 presses the ratchet wheel 80 together with the brake plates 72a and 72b toward the brake receiver 71 (X2 direction) by the action of the male screw portion 26 of the drive shaft 25. , to transmit the drive force to the drive shaft 25 . In this state, even if the drive shaft 25 is rotated in the lowering direction, the female screw member 35 presses the ratchet wheel 80 together with the brake plates 72a and 72b toward the brake receiver 71. As shown in FIG. At this time, since the ratchet wheel 80 is prevented from rotating in the lowering direction by the pawl member 90, the brake device 70 is applied with a braking force due to frictional force. As a result, the rotation of the drive shaft 25 in the lowering direction can be stopped. Conversely, when the female screw member 35 is rotated in the lowering direction, the pressing force of the female screw member 35 is loosened by that amount, the braking force of the brake device 70 is reduced, and it is possible to rotate in the lowering direction.

A pawl shaft 91 is provided integrally with stopper locking members 110 and 120, which will be described later, and a pawl member 90 is rotatably supported on the pawl shaft 91. As shown in FIG. A coil portion 93 a of a torsion spring 93 is attached to the pawl shaft 91 , and the torsion spring 93 provides an urging force in a direction in which the pawl member 90 is pressed against the ratchet teeth 83 of the pawl wheel 80 . In this manner, the ratchet wheel 80 is rotatable in the winding up direction and restricted in rotation in the winding down direction for each pitch angle divided by the number of teeth of the ratchet wheel 80 . A pair of pawl members 90 are provided and are arranged 180 degrees apart in the circumferential direction of the pawl wheel 80 .

The brake device 70 is housed inside one end of the operating lever 50 on the pivot center side, and prevents dust, rainwater, and the like from entering the brake device 70 side. The operating lever 50 has a front cover 50a as a design surface, and a back cover 50b positioned behind the front cover 50a and rotatably held by the lock cover 14. The brake device 70 is arranged in a hollow space provided in the .

The lock cover 14 is in contact with an outer peripheral cover 15 that covers the outer periphery of the rotation lock device 100, which will be described later. 2) is tightened and fixed.

<Regarding the rotation lock device (load drop prevention device) 100>
Next, the rotation lock device 100 will be described. FIG. 4 is an explanatory diagram showing the configuration of the rotation lock device 100. As shown in FIG. FIG. 5 is a perspective view showing the configuration of the rotation lock device 100 shown in FIG. 4. As shown in FIG. As shown in FIGS. 4 and 5, the rotation lock device 100 includes stopper engaging members 110 and 120, a stopper supporting member 130, a stopper member 140, two holding plates 150 and 150 and an unlocking member 170. As shown in FIGS. Here, the stopper engaging member 110 corresponds to the stopper engaging means described in the claims. Also, the unlocking member 170 corresponds to the unlocking means described in the claims.

As shown in FIGS. 4 and 5, stopper engaging members 110 and 120 are attached to the ratchet wheel 80 side of the frame 12 in this embodiment. The stopper locking members 110 and 120 are, for example, elongated members elongated in the Y-axis direction, and a space SP1 is formed between the stopper locking members 110 and 120 . Therefore, the weight of the rotation lock device 100 can be reduced compared to the case where the stopper engaging member is provided so as to cover the entire outer periphery of the stopper support member 130 and the holding plate 150. .

The stopper locking member 110 is attached to the upper end side (Z1 side) of the frame 12 by inserting the stay bolt B1 inserted through the insertion hole 12a of the frame 12 into the attachment holes 111 provided at both ends in the Y-axis direction. It is attached. Further, the stopper engaging member 120 is configured such that the stay bolt B1 inserted through the insertion hole 12b of the frame 12 is inserted through the mounting holes 121 provided at both ends in the Y-axis direction, so that the stopper engaging member 120 is attached to the lower end side (Z2 side) of the frame 12. ). In this embodiment, stopper locking members 110 and 120 are provided with two mounting holes, but may be provided with three or more mounting holes.

The stopper locking member 110 has a recessed portion 112 recessed toward the upper end surface of the stopper locking member 110 at its lower end facing the stopper locking member 120 and at its central portion in the Y-axis direction. One hook portion (not shown) of the torsion spring 93 is engaged with the concave portion 112 . When one hook portion (not shown) of the torsion spring 93 is engaged with the concave portion 112, the stopper member 140 and the hook portion of the torsion spring 93 do not come into contact with each other.

The stopper locking member 110 has a wall surface 112a of the recessed portion 112, a locking wall 113 connected on the left end side in FIG. 5, and an arc-shaped curved surface 114 connected on the right end side of the wall surface 112a in the drawing. The locking wall 113 is a wall surface that collides with the stopper member 140 projecting radially outward from the stopper support member 130 when the load sheave 20 rotates in the lowering direction. Stop rotating in direction. A gap is provided between the lower surface of the stopper locking member 110 and the outer peripheral surface of a holding plate 150, which will be described later, on the left side of the position where the concave portion 112 is provided. By providing this gap, when the stopper member 140 is held in the storage position with respect to the stopper storage portion 133 of the stopper support member 130, the holding plate 150 can be rotated without hindrance.

When the load sheave 20 rotates in the hoisting-down direction or the hoisting-up direction, the curved surface 114 is preferably such that the distal end surface 140a of the stopper member 140 projecting radially outward from the stopper supporting member 130 is in sliding contact with the curved surface 114. The wall surface is arranged with a slight gap from the tip surface 140a of the stopper member 140 protruding radially outward from the stopper support member 130 so as to prevent this from occurring.

Further, the stopper locking member 110 has a substantially flat wall 115 on the lower surface of the stopper locking member 110 on the left side of the concave portion 112 (Y2 side in FIG. 4). A substantially flat wall (hereinafter referred to as push-back wall) 115 protrudes radially outward from the stopper support member 130 when the load sheave 20 rotates in the hoisting direction due to an erroneous operation of the lever hoist 10 . The stopper member 140 is pushed back into the stopper housing portion 133 of the stopper support member 130 along with the sliding contact. If the amount of projection of the stopper member 140 pushed back into the stopper housing portion 133 by the push-back wall 115 is equal to or less than the minimum gap between the stopper supporting member 130 and the stopper locking member 110, the stopper locking member by the stopper member 140 does not move. The sliding contact of 110 with push-back wall 115 is released, and stopper support member 130 and stopper member 140 move beyond locking wall 113 and rotate further. At this time, although illustration is omitted, the stopper projection 141 of the stopper member 140 is positioned radially outward of the holding plate 150 from the tip end portion 155a of the protrusion provided in the guide groove 154 of the holding plate 150, which will be described later. It is held in contact with the inner wall 154c1 of the guide groove 154. As shown in FIG.

Although the push-back wall 115 is a substantially flat wall, when the load sheave 20 rotates in the hoisting direction, the stopper member 140 projecting radially outwardly from the stopper support member 130 slides into contact therewith. As long as the stopper member 140 can be pushed back into the stopper housing portion 133 of the stopper support member 130, the push-back wall 115 is not limited to a substantially flat wall.

Further, the stopper locking member 110 has the pawl shaft 91 described above. In this embodiment, the pawl shaft 91 is integrated with other portions of the stopper locking member 110 . In order to integrate the stopper engaging member 110 and the pawl shaft 91, the stopper engaging member 110 is preferably formed by casting (for example, the lost wax method). Alternatively, the pawl shaft 91 may be formed separately and attached by press-fitting the pawl shaft 91 into a mounting hole or the like present in the stopper locking member 110 .

As shown in FIG. 6, the stopper locking member 110 has a storage recess 116 on the side of the surface 110b facing the frame 12. As shown in FIG. The storage recess 116 has an insertion hole 117 penetrating from the bottom surface 116a of the storage recess 116 toward the front surface 110a on which the pawl shaft 91 is provided. A pivot 172 of an unlocking member 170 described later is inserted through the insertion hole 117 . Since the pivot 172 of the unlocking member 170 is inserted through the insertion hole 117 , the connecting portion 173 of the unlocking member 170 is inserted into the housing recess 116 . The storage recess 116 has a latch pin 118 at a position where the connecting portion 173 of the unlocking member 170 does not interfere. The latching pin 118 latches one end of a tension spring 187 attached to the unlocking member 170 .

Further, the stopper locking member 110 has a recess 119 at a position above the storage recess 116 on the surface 110b on which the storage recess 116 is provided. One end side of a holding shaft 180 (see FIG. 5) projecting in the X1 direction enters from the front surface of the frame 12 into the recess 119 . The holding shaft 180 is attached across the frames 11 and 12 while being inserted through an insertion hole (not shown) provided at one end of the hook 22 .

Returning to FIG. 4 or FIG. 5, the stopper locking member 120 is provided with a projecting portion 122 on the side facing the stopper locking member 110 . The protrusion 122 protrudes toward the stopper support member 130 . The protruding portion 122 faces a stopper support member 130 (to be described later) and an outer peripheral surface of a holding plate 150 rotatably held by the stopper support member 130 with a slight gap therebetween, so that the stopper member 140 is in the retracted position. , so as not to interfere with the rotation of the stopper supporting member 130 and the holding plate 150. As shown in FIG.

Stopper engaging member 120 has a recessed portion 123 recessed toward the lower end surface of stopper engaging member 120 at the upper end facing stopper engaging member 110 and in the central portion in the Y-axis direction. One hook portion (not shown) of a torsion spring (not shown) is engaged with the concave portion 123 . When one hook portion (not shown) of the torsion spring (not shown) is engaged with the concave portion 123, the stopper member 140 and the hook portion of the torsion spring (not shown) do not come into contact with each other.

The projecting portion 122 also has a locking wall 124 that continues to the recessed portion 123 . The locking wall 124 is a wall surface that collides with the stopper member 140 projecting radially outward from the stopper support member 130 when the load sheave 20 rotates in the lowering direction. stop.

On a wall surface (hereinafter referred to as a locking wall) 125 of the projecting portion 122 opposite to the locking wall 124, the stopper supporting member 130 extends in the hoisting direction while the stopper member 140 protrudes radially outward from the stopper supporting member 130. When rotated, the stopper member 140 abuts.

Thus, when the load sheave 20 rotates in the lowering direction with the stopper member 140 protruding radially outwardly of the stopper support member 130 , the stopper member 140 engages the stopper engaging member 110 . It abuts on either the wall 113 or the locking wall 124 of the stopper locking member 120 . Therefore, the rotation of the load sheave 20 in the lowering direction is stopped. On the other hand, when the load sheave 20 rotates in the hoisting direction, the stopper member 140 comes into contact with the locking wall 125 described above. Therefore, the rotation of the load sheave 20 in the hoisting direction is stopped.

For example, when an operator erroneously operates the lever hoist 10 , the operator may not notice that the stopper member 140 protrudes from the stopper support member 130 . As described above, when the chain CH is let out, that is, when the load sheave 20 is rotated in the lowering direction, the stopper member 140 protruding radially outward moves toward the locking wall 113 of the stopper locking member 110 or the stopper locking member 120 . is abutted against one of the locking walls 124 of Further, when the chain CH is wound, that is, when the load sheave 20 is rotated in the winding-up direction, the stopper member 140 projecting radially outward comes into contact with the locking wall 125 of the stopper locking member 120 . Therefore, since the rotation of the load sheave 20 is stopped in the process of feeding or winding the chain CH, the operator can recognize that the rotation lock device 100 is operating. In addition, for example, when the brake device 70 breaks while lifting a load, the chain CH is let out and the load drops. Also, since the dropping of the load is stopped, the operator can recognize that the rotation lock device 100 has been activated and that the brake device 70 has broken.

Further, the stopper locking member 120 has the pawl shaft 91 described above. The pawl shaft 91 may be integrated with the pawl shaft 91 provided on the stopper engaging member 110, or may be a separate member from the stopper engaging member 120 and attached to the stopper engaging member 120. It may be attached by press-fitting into a hole or the like.

The stopper support member 130 has a center hole 131 . The stopper support member 130 is attached to the drive shaft 25 through a center hole 131, and the stopper support member 130 and the drive shaft 25 rotate integrally. The stopper support member 130 may be attached to the drive shaft 25 by any method, such as set screw, key connection, spline connection, etc., as long as the required torque can be transmitted.

The stopper support member 130 has a bearing boss portion 132 . The bearing boss portion 132 is a hollow shaft-like portion protruding in the axial direction (X-axis direction), and is rotatably fitted in the center hole 152 provided in each of the two holding plates 150 .

Further, the stopper support member 130 has a stopper storage portion 133 extending from the center hole 131 side toward the outer peripheral side. The stopper housing portion 133 is a portion for housing a stopper member 140, which will be described later, and has an open outer peripheral side. Therefore, the stopper member 140 housed in the stopper housing portion 133 can protrude toward the outer peripheral side.

The stopper housing portion 133 is formed by being sandwiched between the narrow piece portion 130a and the wide piece portion 130b. When the stopper member 140 collides with either the locking wall 113 of the stopper locking member 110 or the locking wall 124 of the stopper locking member 120, the wide piece portion 130b sandwiches the stopper accommodating portion 133 to lock the stopper. In the circumferential direction of the member 120 , it is located at a site apart from the locking wall 113 or the locking wall 124 . In the configuration shown in FIG. 5 , the narrow piece 130 a is positioned on the left side of the stopper housing portion 133 and the wide piece portion 130 b is positioned on the right side of the stopper housing portion 133 . Here, the wide piece portion 130b is wider in the circumferential direction than the narrow piece portion 130a. Therefore, even if the stopper member 140 collides with either the locking wall 113 or the locking wall 124, the strength is ensured so that the wide piece 130b can receive the impact.

Further, the stopper support member 130 has an insertion hole (not shown) in a portion of the outer peripheral surface of the stopper support member 130 that does not interfere with the center hole 131 and the stopper housing portion 133. One end of a locking pin 181 to be described later is inserted to support the locking pin 181 . One end of a tension spring (coil spring) 186 is hooked on the hook pin 181 . In addition, the tension spring 186 corresponds to the biasing means described in the claims.

As described above, the stopper member 140 is housed in the stopper housing portion 133 of the stopper support member 130 . The stopper member 140 is housed in the stopper housing portion 133 so as to be slidable in the centrifugal direction from the housed position. The retracted position is a position where the stopper member 140 contacts the bottom surface of the stopper storage portion 133 of the stopper support member 130 .

As shown in FIG. 4, when the stopper member 140 is housed in the housing position of the stopper housing portion 133, the outer peripheral surface (surface away from the center in the radial direction) 142 of the stopper member 140 is in the radial direction of the stopper support member 130 (toward the center of rotation of the stopper support member 130). In addition, the distance of the outer peripheral surface of the stopper support member 130 is set to be approximately the same as the distance from the center of the rotating shaft of the holding plate 150 to the outer peripheral surface.

Here, the stopper member 140 is provided with a cylindrical stopper projection 141 . The stopper projection 141 extends from the surface (front surface and back surface) of the stopper member 140 facing the holding plate 150 toward the holding plate 150 (X axis direction). As shown in FIG. 4, the stopper projection 141 is provided closer to the center of the drive shaft 25 (the stopper member 140) than the center of the stopper member 140 in the depth direction (the radial direction of the stopper support member 130). . The stopper projection 141 may be formed integrally with the stopper member 140. However, the stopper projection 141 may be configured by providing a mounting hole in the stopper member 140 and fitting a shaft-like member, a pin, or the like into the mounting hole. may

The stopper projections 141 enter guide grooves 154 provided in a holding plate 150 pivotally supported at both ends of the bearing boss portion 132 in the axial direction. As a result, the stopper projection 141 slides in the guide groove 154 when the positions of the stopper support member 130 and the holding plate 150 change relative to each other in the rotational direction of the drive shaft 25 . When the stopper projection 141 is positioned in the allowable groove portion 154 a described later, the stopper member 140 can protrude toward the outer diameter side of the holding plate 150 according to the centrifugal force acting on the stopper member 140 .

Here, the outermost outer peripheral surface 142 of the stopper member 140 in the radial direction is provided in an arc shape like the outer peripheral surface of the stopper support member 130 and the outer peripheral surface of the holding plate 150 described above. However, the outer peripheral surface 142 may be provided linearly, or may be provided in another shape.

Next, the holding plate 150 is described. As shown in FIGS. 6 and 7, the holding plate 150 is provided in the shape of a disc, and has a center hole 152 at the center in the radial direction. By fitting the bearing boss portion 132 into the center hole 152 , the holding plate 150 is coaxially and rotatably supported with respect to the stopper support member 130 . The distance (that is, the radius) from the center of rotation to the outermost periphery of the holding plate 150 is approximately the same as that to the outermost periphery of the stopper support member 130 . However, one of the stopper support member 130 and the holding plate 150 may have a larger radius.

In this embodiment, a pair of holding plates 150 are provided, and the stopper support member 130 is sandwiched between the pair of holding plates 150 . A pair of holding plates 150 are connected by a connecting member. For example, the connecting member is composed of a rivet 183 and collars (spacers) 184, 185. The collars 184, 185 are arranged between a pair of holding plates 150, and the holes 151 formed in the holding plates 150 and the collars 184, 184, 184, 185 are arranged. The rivets 183 are inserted through the 185 respectively. After that, the pair of holding plates 150 are connected by plastically deforming the other end side of the rivet 183 . In the configuration shown in FIG. 5, the pair of holding plates 150 are connected at four points, but the number of points to be connected may be two, three, or five. or more. Moreover, although rivets and collars are used as connecting members, screws, nuts, and the like may be used as long as they are connected while maintaining the spacing between the pair of holding plates 150 .

The other end side of the tension spring 186 is hooked on the collar 185 described above. The tension spring 186 biases the collar 185 sandwiched between the holding plates 150 toward the locking pin 181 (in the lowering direction). Instead of the tension spring 186 , a configuration including a compression spring or a torsion spring may be used to urge the collar 185 sandwiched between the holding plates 150 toward the locking pin 181 .

A guide groove 154 is provided in the holding plate 150 . The stopper projection 141 of the stopper member 140 enters the guide groove 154 to guide the movement of the stopper projection 141 . The guide groove 154 has a shape in which a groove extending in an arc shape is added to the center side in the radial direction of a substantially triangular portion. Specifically, the guide groove 154 has a substantially triangular holding protrusion 155 as shown in FIG. Three grooves of the restriction groove portion 154c are provided. Here, the gap groove portion 154b corresponds to the first groove portion described in the claims, and the return restricting groove portion 154c corresponds to the second groove portion described in the claims.

The allowable groove portion 154a is a groove portion that allows the stopper projection 141 to move in the radial direction. Therefore, the inner wall 154a1 positioned below the allowable groove portion 154a in FIG. 7 is provided so as to be parallel to the radial direction (one radial direction extending from the center of the center hole 152). The width of the allowable groove portion 154a is defined by the distance between the tip end portion 155a of the holding projection 155 and the inner wall 154a1. It should be noted that the convex tip 155a corresponds to an intersection in the claims.

Further, the gap groove portion 154b is a groove that extends from the convex tip portion 155a along the outer periphery of the center hole 152 in a direction away from the allowable groove portion 154a (to the right in FIG. 7). The gap groove portion 154b enables the stopper protrusion 141 to be positioned with play. Here, an inner wall 154b1 on the outer diameter side of the gap groove portion 154b is a wall surface that abuts (sliding) on the stopper projection 141 to hold the stopper member 140 at the retracted position. Here, the inner wall 154b1 corresponds to the first wall surface described in the claims. When the stopper projection 141 is positioned (entered) into the clearance groove portion 154b, the outer diameter side of the stopper member 140 does not protrude outward from the outer peripheral surface of the stopper support member 130 or the holding plate 150. It is housed in section 143 .

The length of the clearance groove portion 154b in the circumferential direction of the holding plate 150 is formed to be longer than the length determined by the angle γ described below. The pawl wheel 80 described above idles in the lowering direction by an angle (pitch angle) obtained by dividing one circumference by the number of teeth at maximum when the operation is interrupted during the winding operation. Let this angle be an angle γ (not shown). As described above, in the rotation lock device 100, the holding plate 150 is rotatable with respect to the stopper supporting member 130. Therefore, when the stopper supporting member 130 rotates in the lowering direction, the holding plate 150 is pulled by the tension spring 186. is delayed by an angle γ. Therefore, by setting the length of the clearance groove portion 154b in the circumferential direction of the holding plate 150 to at least the length determined by the angle γ, the stopper member 140 can be held even if the stopper support member 130 idles in the lowering direction. It maintains a state in which it does not protrude outward from the outer peripheral surface of the plate 150 .

In the present embodiment, clearance groove portion 154b is sufficiently longer than angle γ. Here, when the length of the clearance groove portion 154b is short, after switching the switching knob 45 to the neutral position and operating the idle rotation gripper 60 to set the idle rotation mode, the chain CH is quickly pulled out in the lowering direction. During the operation, the rotation lock device 100 is easily actuated, and the convenience of pulling out the chain CH is reduced. Therefore, after switching the switching knob 45 to the neutral position to set the idle rotation mode, the length of the clearance groove portion 154b is set to It is sufficiently longer than the angle γ. This prevents the rotation lock device 100 from operating and causing a rotation lock state during the free rotation operation as described above.

The return restricting groove portion 154c is a groove recessed away from the allowable groove portion 154a in the circumferential direction (upward in FIG. 7). The gap groove portion 154b enables the stopper projection 141 to be positioned with play. The return restricting groove portion 154c has an inner wall 154c1. The inner wall 154 c 1 engages with the stopper protrusion 141 to maintain the state where the outer diameter side of the stopper member 140 protrudes from the outer peripheral surface of the stopper support member 130 . That is, the inner wall 154c1 is a wall surface for restricting the stopper member 140 from being completely accommodated in the stopper accommodating portion 133. As shown in FIG. Here, the inner wall 154c1 corresponds to the second wall surface described in the claims. Therefore, the inner wall 154c1 is inclined in the circumferential direction of the holding plate 150 so that the center side (center hole 152) of the holding plate 150 is close to the allowable groove portion 154a.

As shown in FIG. 8, when the outer peripheral surface 142 of the stopper member 140 coincides with the outer peripheral surface of the holding plate 150 on the XZ plane, for example, the tip 155a of the protrusion 155a of the guide groove 154 described above is aligned with the stopper protrusion 141. The center C5 of the guide groove 154 is arranged to be located outside the projection tip 155a of the guide groove 154. As shown in FIG. Therefore, even if the stopper member 140 is pushed in until the outer peripheral surface 142 is aligned with the outer peripheral surface of the holding plate 150, the stopper protrusion 141 of the stopper member 140 is positioned inside the return restricting groove portion 154c. It is designed so that it cannot return to the allowable groove portion 154a. The dashed line T1 is a circle centered on the axis of the drive shaft 25 and passes through the tip end portion 155a of the projection. It is a circle passing through the center of the stopper projection 141 when it coincides with the outer peripheral surface of the plate 150 .

Next, the unlocking member 170 will be described. As shown in FIGS. 6 and 9, the unlocking member 170 is a member that moves (returns) the stopper member 140 protruding from the stopper storage portion 133 of the stopper support member 130 to the storage position described above. The unlocking member 170 is rotatably attached to the stopper locking member 110 . The unlocking member 170 is brought to an initial position (see FIG. 5) where the upper surface of the main body 171 (to be described later) abuts the lower surface of the stopper engaging member 110 by means of a tension spring 187 arranged across the stopper engaging member 110 . retained.

When the lock release member 170 is at the initial position, the pressing portion 177 provided on the side of the main body 171 of the lock release member 170 is substantially flush with the outer peripheral cover 15 as shown in FIG. When the operator presses the pressing portion 177 of the unlocking member 170 when unlocking the rotation lock device 100 , the unlocking member 170 resists the urging force of the tension spring 187 and the holding plate 150 is pushed. (toward the inside of the outer peripheral cover 15). At this time, push-in projections 195, which will be described later, enter between holding plates 150, and move stopper members 140 protruding from stopper support member 130 into stopper housing portion 133 of stopper support member 130 (see FIG. 14).

Returning to FIGS. 6 and 9, the unlocking member 170 has a main body 171 and a pivot 172 which are connected by a connecting portion 173 . The main body 171 has a hollow portion 174 recessed from the surface on the rear side facing the frame 12 . The hollow portion 174 is provided with a locking pin 175 protruding from the bottom surface 174a of the hollow portion 174 at its lower end. A locking pin 175 locks the other end of the tension spring 187 . The tension spring 187, the other end of which is locked by the locking pin 175, is accommodated in the above-described hollow portion 174, and extends from the recess 176 provided in the upper surface 171a of the main body 171 to the storage recess 116 of the stopper locking member 110. One end thereof is engaged with the engaging pin 118 of the stopper engaging member 110 described above.

A pressing portion 177 is provided on the side surface of the main body 171 . The pressing portion 177 has, for example, four protrusions 177a that are vertically spaced apart from each other. By providing the four protrusions 177 a on the pressing portion 177 , when the operator presses the pressing portion 177 of the unlocking member 170 with his/her finger, the finger is prevented from slipping. Note that the number of projections 177a provided on the pressing portion 177 is not limited to four. Further, instead of providing the protrusion 177a, the surface of the pressing portion 177 may be subjected to surface treatment (surface processing) to prevent the finger from slipping.

The main body 171 has a raised portion 178 at the end of the front surface 171b on the Y2 side. The raised portion 178 protrudes from the front surface 171 b of the main body 171 . Also, the raised portion 178 protrudes outward from the left side surface 171c of the main body 171 . The side surface 171c is configured, for example, by arranging arc-shaped curved surfaces 191, 192, and 193 so as to line up in the vertical direction. Also, in the arrangement of the curved surfaces 191 , 192 , 193 , the curved surface 192 located in the center is close to the holding plate 150 .

The curved surface 191 comes into sliding contact with the outer peripheral surface 142 of the stopper member 140 when the load sheave 20 rotates in the hoisting direction with the stopper member 140 protruding from the outer peripheral surface of the holding plate 150 when the lock release member 170 is pressed. , the stopper member 140 is moved to a position where the outer peripheral surface 142 of the stopper member 140 coincides with the outer peripheral surface of the holding plate 150 . Here, the curved surface 191 corresponds to the sliding contact surface described in the claims.

The curved surface 192 abuts against the outer peripheral surface of the holding plate 150 when the unlocking member 170 is pressed. Therefore, the curved surface 192 is an arc whose radius in the YZ plane is the same as the radius of the outer peripheral surface of the holding plate 150. The only contact with the outer peripheral surface of the holding plate 150 may be employed.

Here, the side surface 171c is formed by combining curved surfaces 191, 192, and 193, but the stopper member 140, which is in sliding contact with the stopper member 171c, can be moved toward the stopper housing portion 133 of the stopper support member 130. Instead of curved surfaces 191, 193, two flat surfaces may be used.

The curved surface 192 is provided with a pushing protrusion 195 that protrudes toward the holding plate 150 . The push-in protrusion 195 corresponds to the push-in portion described in the claims. The pushing protrusion 195 is held at a position away from the outer peripheral surface of the holding plate 150 when the unlocking member 170 is at the initial position. When the unlocking member 170 is pressed and the unlocking member 170 moves toward the holding plates 150 , the pushing projection 195 enters the gap between the two holding plates 150 . Then, the stopper member 140 moved to a position where the outer peripheral surface 142 matches the outer peripheral surface of the holding plate 150 is pushed toward the center of rotation of the stopper support member 130, that is, toward the center of the drive shaft 25 (see FIG. 14). It should be noted that when the lock release member 170 is pressed and the pushing projection 195 enters the gap between the two holding plates 150, the center C5 of the stopper projection of the stopper member 140 is positioned closer to the drive shaft 25 than the projection tip 155a. It is sufficient that the stopper member 140 can be pushed into the stopper housing portion 133 of the stopper support member 130 until the stopper member 140 is positioned on the axial center side of the stopper member 130 .

Therefore, the height of the push-in protrusion 195 (the amount of protrusion from the curved surface 192) is, for example, from the center of the holding plate 150 to the stopper protrusion 141 when the outer peripheral surface 142 of the stopper member 140 matches the outer peripheral surface of the holding plate 150. is set longer than the difference D1 (see FIG. 8) between the distance to the center C5 of the holding plate 150 and the distance from the center of the holding plate 150 to the projection tip 155a. As a result, when the stopper member 140 is pushed by the push-in projection 195, the center of the stopper projection 141 of the stopper member 140 is pushed toward the center of the holding plate 150 relative to the distal end portion 155a of the protrusion in the radial direction of the holding plate 150. . This allows the stopper projection 141 to move from the allowance groove portion 154a to the clearance groove portion 154b.

The pivot 172 is inserted through the insertion hole 117 provided in the storage recess 116 from the storage recess 116 side of the stopper locking member 110 . Since the pivot 172 is inserted and held in the insertion hole 117 of the stopper locking member 110, when the pressing portion 177 is pressed, the unlocking member 170 moves to the initial position about the pivot 172. , toward the holding plate 150 .

<About action>
In the hoisting operation of the lever hoist 10 equipped with the rotation lock device 100 described above, if the brake device 70 is damaged or the like, the drive shaft 25 is accelerated and rotated in the hoisting-down direction due to the tension of the chain CH due to the lifting load or the like. Consider when to start.

When the brake device 70 is damaged, the drive shaft 25 and the stopper support member 130, which have lost their braking force, start to rotate with rapid acceleration in the lowering direction (the arrow direction in FIG. 10) due to the tension applied to the chain CH. At this time, the biasing force of the tension spring 186 pushes the holding plate 150 to the stopper member 140 with the stopper projection 141 of the stopper member 140 positioned at the extreme end of the clearance groove 154b (the end on the side away from the allowable groove 154a). It works to follow the rotation of However, when the inertial force acting on the holding plate 150 exceeds the biasing force of the tension spring 186, the stopper projection 141 separates from the end of the clearance groove 154b (the end on the side away from the allowable groove 154a). Further, when the driving shaft 25 accelerates and rotates together with the stopper support member 130 and the stopper member 140 due to the acceleration that causes the stopper projection 141 to move away from this end (cannot follow), the inertial force acting on the holding plate 150 stretches the tension spring 186 . , the stopper projection 141 of the stopper member 140 slides in the clearance groove portion 154b toward the allowance groove portion 154a.

Even if the stopper member 140 attempts to protrude radially outward due to the centrifugal force generated by the rotation of the stopper support member 130 and the stopper member 140, the stopper projection 141 does not move until it reaches the allowable groove portion 154a. By being restricted by the inner wall 154b1, protrusion of the stopper member 140 to the outer diameter side is restricted.

10, the stopper member 140 can protrude radially outward when the stopper projection 141 moves relatively within the clearance groove 154b. That is, the stopper member 140 released from the engagement (holding) state between the stopper protrusion 141 and the inner wall 154b1 protrudes radially outward from the stopper accommodating portion 133 due to the centrifugal force. However, the protrusion to the outer diameter side is within the range up to the outermost peripheral side of the guide groove 154 . Further, even if the rotational acceleration in the lowering direction of the drive shaft 25 decreases after the stopper member 140 slides in the centrifugal direction from the predetermined position and the stopper projection 141 passes over the tip end portion 155a of the projection, the tension spring 186 still remains. , the stopper projection 141 is pressed by the inner wall 154c1. By this pressing, the stopper member 140 protrudes to a position where it reliably engages with the locking wall 113 of the stopper locking member 110, and the engagement is maintained while the load in the lowering direction continues on the drive shaft 25. .

When the stopper member 140 projecting from the stopper storage portion 133 continues to rotate in the lowering direction, it collides with the locking wall 113 of the stopper locking member 110 as shown in FIG. As a result, the rotation of the stopper support member 130 and the drive shaft 25 in the lowering direction is stopped, and the drop of the load is stopped.

After the stopper member 140 collides with the locking wall 113 of the stopper locking member 110, the stopper projection 141 enters the return restricting groove portion 154c. As a result, after the drive shaft 25 stops, the stopper projection 141 receives the biasing force of the inner wall 151c1 in the lowering direction due to the biasing force of the tension spring 186, so that the stopper projection 141 is engaged with the return restricting groove portion 154c. state is maintained. At this time, even if the stopper member 140 inadvertently tries to return to the stopper housing portion 133, the stopper projection 141 maintains engagement with the inner wall 154c1, thereby regulating the return of the stopper member 140 to the stopper housing portion 133. be. Therefore, the rotation stop state of the drive shaft 25 is maintained, that is, the load is prevented from falling again.

On the other hand, the lever hoist 10 adjusts the payout length of the chain CH by operating the operation lever 50 and the free rotation grip 60 to wind up or lower the chain CH, and also directly operates the chain CH to adjust the payout length. It has an idle rotation mechanism that can adjust the thickness. In this embodiment, it is possible to switch to the idle rotation mode by switching the switching knob 45 to the neutral position and pulling out the idle rotation grip 60 . In this state, it is possible to pull out the chain CH vigorously in the lowering direction, and as a result, the rotation lock device 100 may be activated.

In addition, when the chain CH is slack with a load hung on a hook (not shown) provided at the lower end of the chain CH, the hook of the chain CH is separated from the load sheave 20 so as to eliminate the slack of the chain CH. , the slackness of the chain CH disappears, and the rotation of the drive shaft 25, the load sheave 20 and the stopper support member 130, which had been rotating in the hoisting direction, suddenly stops in the hoisting direction. become. While the rotation of these members is abruptly stopped, the holding plate 150 continues to rotate in the winding direction, and the relative positions of the holding plate 150 and the stopper support member 130 in the circumferential direction change. Due to this change in relative position, the stopper protrusion 141 of the stopper member 140 moves from the clearance groove 154b into the return restricting groove 154c via the allowance groove 154a, and the rotation lock device 100 is locked.

In order to cancel the stoppage of rotation of the drive shaft 25 in the lowering direction, the switching knob 45 is switched from the lowering position to, for example, the lifting position. Then, the pressing portion 177 of the unlocking member 170 at the initial position is pressed. When the pressing portion 177 of the unlocking member 170 is pressed, the unlocking member 170 is directed toward the holding plate 150 against the urging force of the tension spring 187 arranged across the stopper locking member 110 . to tilt. As shown in FIG. 12 , when the unlocking member 170 tilts toward the holding plates 150 , the pushing protrusions 195 enter between the holding plates 150 . Then, the curved surface 192 abuts against the outer peripheral surface of the holding plate 150 .

In this state, the free rotation gripper 60 is rotated in the hoisting direction, or the operating lever 50 is used to perform the hoisting operation. In accordance with this operation, the drive shaft 25 rotates in the hoisting direction (the arrow direction in FIG. 12). As the drive shaft 25 rotates in the winding direction, the stopper supporting member 130 and the stopper member 140 also rotate in the same direction. At this time, the stopper protrusion 141 of the stopper member 140 is engaged with the return restricting groove portion 154c. Therefore, the stopper projection 141 of the stopper member 140 rotating in the winding direction presses the inner wall 154c1 of the return restricting groove portion 154c. As a result, the holding plate 150 also rotates in the winding direction together with the stopper supporting member 130 and the stopper member 140 .

When the stopper member 140 that rotates in the wind-up direction rotates a predetermined amount, it moves while being in sliding contact with the curved surface 191 of the unlocking member 170 . At this time, when the unlocking member 170 at the initial position is pressed, the push-in projection 195 is held between the holding plates 150 . As shown in FIG. 13, when the stopper support member 130 rotates in the winding direction, the push-in projection 195 rides on the wide piece 130b of the stopper support member 130 while moving toward the initial position. At this time, the stopper member 140 rotates while being in sliding contact with the curved surface 191 of the unlocking member 170, and at the same time, the stopper member 140 moves toward the inside of the stopper accommodating portion 133 of the stopper supporting member 130 (toward the driving shaft 25). axis).

Further, when the free rotation barb 60 is rotated in the winding-up direction, the outer peripheral surface of the stopper member 140 rotates while being in sliding contact with the curved surface 191 . Thereby, the stopper member 140 moves to the stopper storage portion 133 of the stopper support member 130 . That is, the amount of protrusion of the stopper member 140 from the outer peripheral surface of the holding plate 150 is reduced by sliding contact with the curved surface 191 .

As shown in FIG. 14, when the stopper support member 130 continues to rotate and the sliding contact between the push-in projection 195 and the wide piece portion 130b of the stopper support member 130 is released, the push-in projection 195 is again moved to the holding plate. Enter the gap of 150. The position at which the sliding contact between the push-in projection 195 and the wide piece 130b of the stopper support member 130 is released is the position of the stopper housing portion 133 of the stopper support member 130. As shown in FIG. When the push-in projection 195 enters the gap of the holding plate 150 , the push-in projection 195 pushes the stopper member 140 into the stopper housing portion 133 . As described above, the height of the pushing protrusion 195 is, for example, the distance from the center of the holding plate 150 to the center C5 of the stopper protrusion 141 when the outer peripheral surface 142 of the stopper member 140 matches the outer peripheral surface of the holding plate 150. , and the distance from the center of the holding plate 150 to the tip end portion 155a of the projection portion 155a. Therefore, the stopper member 140 pushed by the push-in projection 195 is moved to a position where the stopper projection 141 is inside the convex end portion 155a of the guide groove 154 of the holding plate 150, that is, the stopper projection 141 enters the clearance groove portion 154b. do.

At this time, a biasing force is applied to the tension spring 186 to pull the collar 185 toward the locking pin 181 . Therefore, when the stopper projection 141 of the stopper member 140 pressed by the push-in projection 195 moves to the position where it enters the clearance groove portion 154b, the holding plate 150 rotates in the direction opposite to the winding direction. When the stopper projection 141 of the stopper member 140 contacts the clockwise end of the clearance groove 154b, the rotation is stopped. Thereby, the stopper member 140 is held at the retracted position. When the stopper member 140 is held at the retracted position, the rotation stop state of the drive shaft 25 is released. Then, the pressing force of the unlocking member 170 against the pressing portion 177 is also released, and the unlocking member 160 is returned to the initial position by the biasing force of the tension spring 187 . By rotating the load sheave 20 about halfway in the hoisting direction while the lock release member 160 is pressed, the rotation lock device 100 can be unlocked.

In the above description, after switching the switching knob 46 to the hoisting position, the operation of releasing the rotation stop state of the drive shaft 25 is performed. An operation to release the rotation stop state of 25 may be performed.

In the above description, the stopper engaging member 120 provided with the projecting portion 122 is provided at a position facing the stopper engaging member 110 . Therefore, the stopper member 140 protruding to the outer diameter side of the holding plate 150 may collide with the locking wall 124 of the stopper locking member 120 . In such a case, when the stopper supporting member 130 is rotated in the hoisting direction, the stopper member 140 comes into sliding contact with the push-back wall 115 of the stopper locking member 110 . Due to this sliding contact, the stopper member 140 can continue to rotate in the winding-up direction beyond the locking wall 113 while moving toward the stopper housing portion 133 of the stopper support member 130 . Therefore, by rotating the load sheave 20 about one turn in the hoisting direction while the lock releasing member 170 is being pressed, the rotation locked state of the rotation lock device 100 can be released.

The above description exemplifies the rotation lock device 100 in which the stopper engaging member 110 and the stopper engaging member 120 provided with the projecting portion 122 are provided at opposing positions. Since it is sufficient to stop the rotation of the drive shaft 25 between may be In this case, by providing an unlocking member for each of the arranged stopper engaging members 120, the rotation locked state of the rotation locking device due to malfunction can be released.

In the above description, the unlocking member is provided only on the stopper engaging member 110, but the unlocking member is also provided on the stopper engaging member 120. can be left open.
<About effect>

As described above, the rotation lock device 100 for locking the drive shaft 25 from abrupt rotation in one direction includes a stopper member 140 having a stopper projection 141 along the axial direction of the drive shaft 25 and an axis of the drive shaft 25. A stopper support member 130 that supports a stopper member 140 in a slidable state outwardly from the center side and rotates integrally with the drive shaft 25; 154b, and a return restricting groove portion 154c located outside the clearance groove portion 154b in the radial direction of the drive shaft 25 at the side end of the clearance groove portion 154b in the lowering direction. The holding plate 150 is rotatably attached to the stopper supporting member 130 with the stopper projection 141 of the stopper inserted into the guide groove 154, and the holding plate 150 is attached to the stopper supporting member 130 in the lowering direction. A tension spring 186 that presses and holds the stopper projection 141 of the stopper member 140 in either the clearance groove portion 154b or the return restriction groove portion 154c of the guide groove 154 causes the drive shaft 25 to wind at an acceleration exceeding a predetermined acceleration. When rotated in the downward direction, the stopper support member 130 rotating together with the drive shaft 25 is inserted into the clearance groove 154b due to the change in the relative position of the stopper member 130 with respect to the holding plate 150 and the centrifugal force of the stopper member 140 rotating together with the stopper support member 130. As the stopper protrusion 141 held in the pressed state moves to the return restricting groove portion 154c, the stopper member 140 projecting from the outer peripheral edge of the stopper support member 130 collides with the stopper protrusion 141, thereby moving the drive shaft 25 in the lowering direction. A stopper locking member 110 having a locking wall 113 for stopping the rotation of the stopper member 110 and a stopper member 140 protruding outward from the outer peripheral surface of the stopper support member 130 are pushed toward the axial center of the drive shaft 25 and inserted into the return restricting groove 154c. and a lock release member 170 that releases the stoppage of rotation of the drive shaft 25 in the lowering direction by moving the stopper projection 141 of the inserted stopper member 140 to the clearance groove portion 154b.

According to this, when the drive shaft 25 is accelerated and rotated in the lowering direction by the tension applied to the chain CH due to the suspension load, for example, the chain CH can be pulled out in the lowering direction by pulling it by hand. At this time, when the chain CH is pulled out in the lowering direction at a speed higher than necessary, or when the chain CH is hoisted up in the hoisting direction to eliminate the slack in the chain CH, the rotation lock device 100 is activated. The stopper member 140 protrudes from the stopper support member 130 and comes into contact with the locking wall 113 of the stopper locking member 110, thereby stopping the rotation of the drive shaft 25 in the lowering direction. The stopper member 140 projecting from the stopper support member 130 is moved to the axial center side of the drive shaft 25 by the lock release member 170 , and the state of projecting from the stopper support member 130 is released. That is, the unlocking member 170 can easily unlock the rotation lock device 100 .

In addition, in the rotation lock device 100 of the present embodiment, the stopper projection 141 of the stopper member 140 comes into contact with the gap groove portion 154b due to the centrifugal force acting on the stopper member 140 when the stopper member 140 rotates together with the stopper support member 130. The return restricting groove portion 154c has an inner wall 154b1, and the stopper protrusion 141 of the stopper member 140 is held in the return restricting groove portion 154c. In addition, it has an inner wall 154c1 with which the stopper protrusion 141 of the stopper member 140 held in the return restricting groove portion 154c abuts. The tip end portion 155a of the projection portion is located closer to the axial center side of the drive shaft 25 than the center C5 of the stopper protrusion 141 of the stopper member 140 when the outer peripheral surface of the stopper member 140 and the outer peripheral surface of the stopper support member 130 are flush with each other. The unlocking member 170 presses the stopper member 140 toward the axial center of the drive shaft 25, so that the center C5 of the stopper projection 141 of the stopper member 140 is driven from the position of the tip end portion 155a of the protrusion portion 155a in the YZ plane. It is moved to a position on the axial center side of the shaft 25 .

According to this, once the stopper protrusion 141 protrudes from the outer peripheral surface of the stopper support member 130, the outer peripheral surface 142 of the stopper protrusion 141 is simply pushed into the stopper housing portion 133 until it becomes flush with the outer peripheral surface of the stopper support member. Then, the lock of the rotation lock device 100 is not released. That is, it is possible to prevent the lock of the rotation lock device 100 from being erroneously released. On the other hand, the stopper member 140 can be pressed toward the axial center side of the drive shaft 25 using the unlocking member 170, thereby moving the center C5 of the stopper protrusion 141 of the stopper member 140 to the tip of the protrusion. It can be easily moved to a position closer to the center of the drive shaft 25 than the position 155a.

Further, in the rotation lock device 100 of the present embodiment, the unlocking member 170 is rotated from the outer peripheral surface of the stopper support member 130 when the drive shaft 25 is rotated in the winding-up direction opposite to the winding-down direction. The stopper member 140 is brought into sliding contact with the stopper member 140 projecting outward, and the stopper member 140 is moved in the axial direction of the drive shaft 25 until the outer peripheral surface of the stopper member 140 is flush with the outer peripheral surface of the stopper support member 130 . The stopper member 140 is pushed toward the axis of the drive shaft 25 until the curved surface 191 and the center C5 of the stopper projection 141 of the stopper member 140 are closer to the axis of the drive shaft 25 than the tip 155a of the projection. It has a protrusion 195 .

According to this, when the drive shaft 25 is rotated in the winding direction, the outer peripheral surface of the stopper member 140 is flush with the outer peripheral surface of the stopper support member 130 while the stopper member 140 is in sliding contact with the connecting portion 173 and the curved surface 191 . The stopper supporting member 130 is moved toward the stopper accommodating portion 133 until it becomes a flat surface. After that, the stopper member 140 is pushed into the stopper housing portion 133 of the stopper support member 130 by the pushing projection 195 of the unlocking member 170 . Therefore, the height of the push-in protrusion 195 is the center of the stopper protrusion 141 when the outer peripheral surface of the stopper member 140 is flush with the outer peripheral surface of the stopper support member 130 in a circle centered on the axis of the drive shaft 25 . The difference D1 between the radius of the circle passing through C5 and the radius of the circle passing through the tip end portion 155a of the convex portion 155a should be larger than the difference D1. Damage to the protrusion 195 can be prevented.

Further, in the rotation lock device 100 of the present embodiment, the unlocking member 170 is rotatably attached to the stopper engaging member 110 in a state of being biased toward the stopper engaging member 110. Reference numeral 170 presses the stopper member 140 projecting outward from the outer peripheral surface of the stopper support member 130 toward the axial center of the drive shaft 25 by receiving pressure toward the holding plate 150 .

According to this, unless the unlocking member 170 is pressed, the unlocking member 170 does not rotate toward the holding plate 150. Therefore, if the unlocking member 170 is erroneously pressed, the rotation locking device will be locked. 100 is prevented from being unlocked.

The hoisting machine described in the present embodiment includes the rotation lock device 100 described above, the load sheave 20 pivotally supported by a pair of frames 11 and 12 and around which a chain CH for lifting a load is wound, and the load sheave 20 and a drive shaft 25 connected via a reduction gear 30, an operation lever 50 for rotating the load sheave 20 in either the lowering direction or the hoisting direction opposite to the lowering direction, the drive shaft 25 and has ratchet teeth on the outer peripheral side, a pawl member 90 that engages with the ratchet teeth, and a pawl shaft 91 that supports rotation of the pawl member 90. The ratchet teeth and and a brake device 70 having a ratchet mechanism that permits rotation of the ratchet wheel 80 in the winding-up direction and prohibits rotation in the winding-down direction by engagement with the pawl member 90 .

According to this, for example, when the brake device 70 is damaged and the drive shaft 25 is accelerated and rotated in the lowering direction due to the tension of the chain CH due to the suspension load, or when the chain CH is manually pulled and wound. When the chain CH is pulled out in the lowering direction at a speed higher than necessary in the free rotation mode in which it can be pulled out in the lowering direction, the rotation lock device 100 is actuated and the stopper member 140 is pulled out from the stopper supporting member 130. , and collides with the locking wall 113 of the stopper locking member 110 to stop the rotation of the drive shaft 25 in the lowering direction. The stopper member 140 projecting from the stopper support member 130 is moved to the axial center side of the drive shaft 25 by the lock release member 170 , and the state of projecting from the stopper support member 130 is released. That is, the unlocking member 170 can easily unlock the rotation lock device 100 .

10 Lever hoist (winding machine)
Reference Signs List 11, 12 Frame 20 Load sheave 25 Drive shaft (shaft-like member)
REFERENCE SIGNS LIST 30: Reduction gear 50: Operation lever 70: Brake device 80: Pawl wheel 90: Pawl member 91: Pawl shaft 100: Rotation lock device 110: Stopper engaging member (stopper engaging means)
113... Locking wall 130... Stopper support member 140... Stopper member 141... Stopper projection (projection)
150... Holding plate 154... Guide groove 154b... Spacing groove (first groove)
154b1... Inner wall (first wall surface)
154c... Return restricting groove (second groove)
154c1... Inner wall (second wall surface)
155a... Projection tip (intersection point)
170... Lock release member (release member)
186 ... Tension spring (biasing means)
191... Curved surface (sliding contact surface)
195 ... push-in protrusion (push-in portion)

Claims (5)

A rotation lock device that locks a sudden rotation of a shaft-shaped member in one direction,
a stopper member having a projection along the axial direction of the shaft-shaped member;
a stopper supporting member that supports the stopper member in a slidable state outwardly from the axial center side of the shaft-shaped member and rotates integrally with the shaft-shaped member;
A first groove portion extending in an arc shape along the circumferential direction of the shaft-shaped member, and a side end portion of the first groove portion in the one direction extending outward from the first groove portion in the radial direction of the shaft-shaped member. a holding plate having a guide groove including a positioned second groove portion, the holding plate being rotatably attached to the stopper support member in a state in which the projection of the stopper member is inserted into the guide groove;
The holding plate is biased toward the one direction with respect to the stopper support member to hold the protrusion of the stopper member in either the first groove or the second groove of the guide groove. a biasing means;
When the shaft-shaped member rotates in the one direction exceeding a predetermined acceleration, the relative position of the stopper support member rotating together with the shaft-shaped member changes with respect to the holding plate; The stopper member protrudes from the outer peripheral edge of the stopper support member as the projection held in the first groove moves toward the second groove due to the centrifugal force of the stopper member. a stopper locking means having a locking wall that stops the rotation of the shaft-shaped member in the one direction by colliding with the
The stopper member protruding outward from the outer peripheral surface of the stopper support member is pushed toward the axial center of the shaft member, and the protrusion of the stopper member inserted into the second groove is moved to the first groove. a release means for releasing the stoppage of rotation of the shaft-shaped member in the one direction by
A rotation lock device characterized by comprising: A rotation lock device according to claim 1, wherein
the first groove portion has a first wall surface against which the protrusion of the stopper member abuts due to a centrifugal force acting on the stopper member when the stopper member rotates together with the stopper support member;
When the holding plate is rotated in the one direction by the force of the biasing means in a state where the projection of the stopper member is held in the second groove, the second groove is formed in the second groove. having a second wall surface with which the projection of the held stopper member abuts,
In a plane orthogonal to the axial direction, the intersection of the first wall surface and the second wall surface is the above-mentioned cross section of the stopper member when the outer peripheral surface of the stopper member is flush with the outer peripheral surface of the stopper support member. positioned closer to the axis of the shaft-shaped member than the center of the projection,
The releasing means pushes the stopper member toward the shaft center side of the shaft-shaped member until the center of the protrusion is closer to the shaft center side of the shaft-shaped member than the position of the intersection on the plane. rotating locking device. A rotation lock device according to claim 2, wherein
The releasing means is
When the shaft-like member is rotated in the other direction opposite to the one direction, it is brought into sliding contact with the stopper member protruding outward from the outer peripheral surface of the stopper support member, and the outer peripheral surface of the stopper member. a sliding contact surface for moving the stopper member in the axial direction of the shaft-shaped member until the outer peripheral surface of the stopper support member is flush with the outer peripheral surface of the stopper support member;
a pushing portion that pushes the stopper member toward the shaft center side of the shaft-shaped member until the center of the protrusion of the stopper member is closer to the shaft center side of the shaft-shaped member than the position of the intersection point;
A rotation lock device comprising: In the rotation lock device according to any one of claims 1 to 3,
the releasing means is rotatably attached to the stopper locking means while being biased in a direction away from the holding plate;
The rotation lock device is characterized in that the releasing means pushes the stopper member protruding outward from the outer peripheral surface of the stopper support member toward the shaft center side of the shaft-shaped member when pressed toward the holding plate. . a rotation lock device according to any one of claims 1 to 4;
A load sheave that is pivotally supported by a pair of frames and has a chain for lifting a load wrapped around it;
a drive shaft connected to the load sheave via a reduction gear and corresponding to the shaft-like member;
an operation lever that rotates the load sheave in one of a hoisting direction corresponding to the one direction and a hoisting direction opposite to the hoisting direction;
a pawl wheel mounted around the shaft-shaped member and having ratchet teeth on the outer peripheral side; a pawl member engaged with the ratchet teeth; and a pawl shaft supporting rotation of the pawl member, wherein the ratchet a brake device having a ratchet mechanism that permits rotation of the ratchet wheel in the winding-up direction and prohibits rotation in the winding-down direction by engaging the teeth with the pawl member;
A hoist, comprising:

Images