JP2006273491A - Rotation drive device in winding-up machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that a stroke in an axial direction of an urging means is small, height of an engagement claw for preventing over-load is small, a ratio of error of manufacture tolerance relative to the height of the claw becomes large and operation stability of a product is impaired in a rotation drive member used for a conventional over-load prevention device of a winding-up machine. <P>SOLUTION: The rotation drive device in the winding-up machine is provided with the over-load prevention means fitted to a fitting recession part of an inner periphery of a hand wheel of the winding-up machine and transmitting drive of the hand wheel 9 to a drive member. The rotation drive device 11 has an annular link 11e; and a plurality of laterally long projections 11b extending and projecting from an outer periphery of the annular link 11e in an axial direction of the drive member and fitted to the inner periphery of the hand wheel in a width direction. An engagement tooth 11a for preventing the over-load engaged with an engagement tooth provided on the drive member is provided on a drive member side end of the projection 11b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rotary drive device mounted as an overload prevention device for a hoisting machine such as a chain block.

Conventionally, a drive shaft for driving a load sheave, a pressure receiving member fixed to the drive shaft, a drive member screwed to the drive shaft so as to be able to advance and retract, and a drive member that is rotatably fitted, A hoisting machine including a rotary drive member that transmits drive of a drive wheel to a pressing drive member is known. In such a hoisting machine, as an overload prevention device for facilitating the adjustment of the limit load of the suspended load and easily unwinding even in an overload state, a pressing drive member and It is known that the rotation drive member is provided with locking teeth so that the rotation drive member idles with respect to the pressing drive member when overloaded. (For example, see Patent Document 1)
Hereinafter, the overload prevention apparatus described in Patent Document 1 will be described with reference to FIGS. 15 and 16.

  FIG. 15 is a front view showing a conventional hoisting machine, and FIG. 16 is an exploded perspective view showing a main part of an overload prevention device for the hoisting machine. In FIG. 15, a drive shaft 22 is rotatably inserted in the load sheave 21. The drive shaft 22 is formed with a screw portion 22a, and the pressure receiving member 24 and the drive member 30 are screwed into the screw portion 22a from the side closer to the load sheave 21, and the pressure receiving member 24 is connected to the screw portion 22a. It is screwed to the innermost part and is fixed to the drive shaft 22. The pressure-receiving member 24 has a large-diameter disk portion 24a and a small-diameter boss portion 24b concentrically. The boss portion 24b is sandwiched between a pair of friction members 29 and 29 and an anti-reverse wheel 27 is fitted outside. Has been. The anti-reverse wheel 27 and the friction members 29 and 29 disposed on both sides of the anti-reverse wheel 27 are configured to be pressed against the disk portion 24a of the pressure receiving member 24 by the driving member 30. The anti-reverse wheel 27 is provided with a locking tooth 27a inclined on one side in the circumferential direction on the outer periphery, and the reverse rotation prevention is achieved by engaging the locking tooth 27a with a ratchet claw 28 pivotally supported on the side plate. The wheel 27 is prevented from being reversely rotated, and can rotate only in one direction with respect to the drive shaft, that is, in the winding direction. Also, in FIG. 16, the same shape of locking teeth 30c is formed on the outer disk surface portion of the front end surface in the axial direction of the flange portion 30a of the drive member 30 by the large-diameter boss portion 30b. A rotary drive member 32 is fitted on the large-diameter boss portion 30 b of the drive member 30, and the axial base end surface of the rotary drive member 32 is engageable with the locking teeth 30 c of the drive member 30. Stop teeth 32a are formed to protrude toward the proximal end in the axial direction. Each locking tooth 32 a of the rotary drive member 32 is formed in a shape that is substantially matched with a concave groove formed between the locking teeth 30 c of the drive member 30. A hand wheel 34 is fitted on the outer periphery of the rotation drive member 32. The rotation drive member 32 is positioned relative to the drive member 30 through a disk-shaped rotation limiting member 35 and a disc spring 33 which is a biasing means on a screw portion of a small-diameter boss 30d on the distal end side of the drive member 30. This is done by screwing the nut 36. A plurality of substantially short engaging convex portions 35 a are formed on the inner peripheral portion of the rotation limiting member 35 so as to protrude radially inward. The rotation restricting member 35 is restricted from moving relative to the drive member 30 in the circumferential direction, but can be moved in the axial direction. The disc spring 33 exerts an urging force so as to press the rotation drive member 32 in the axial base end direction (the drive member 30 side) via the rotation limiting member 35.

Next, the use of this conventional hoisting machine will be described. First, the nut 36 is screwed in, and the disc spring 33 as an urging means presses the rotation limiting member 35 toward the axial base end side. Since the rotation limiting member 35 is in contact with the rotation drive member 32, the rotation drive member 32 is biased toward the drive member 30. At this time, the locking teeth 30c of the drive member 30 and the locking teeth 32a of the rotation drive member 32 are engaged with each other. When a load equal to or lower than the limit load is suspended on the load chain wound around the load sheave 1, when the handwheel 34 is operated to rotate the rotation drive member 32, the rotation is caused by the locking teeth 32a, It is transmitted to the drive member 30 through 30c, and the pressure receiving member 23 can be pressed and rotated by the drive member 30 to wind up the load. On the other hand, when an overloaded load is lifted, if the rotary drive member 32 is rotated by the handwheel 34, the rotary drive member 32 resists the urging force of the disc spring 33 together with the handwheel 34. Then, the pressing surface of the locking tooth 32 a is pushed up along the winding pressing surface of the locking tooth 30 c of the driving member 30 while being pushed back to the front end side in the axial direction. Gets over the locking teeth 30c of the driving member 30 and is engaged in the next groove between the locking teeth 30c of the driving member 30 by the biasing force of the disc spring 33. As described above, when the handwheel 34 is rotated in the winding direction in an overload state, the drive member 30 does not rotate, but only the rotation drive member 32 rotates and the drive member 30 cannot be rotated forward. Overload lifting is prevented.
Japanese Patent No. 309629 (see pages 3 to 5, see FIGS. 1 and 2)

  However, the overload prevention device in the conventional hoisting machine has a structure in which the urging means and the nut that presses the urging means are stacked on the driving member, so in order to reduce the size of the hoisting machine, As a biasing means, a small stroke biasing means such as a disc spring has to be used, so that the axial stroke of the biasing means becomes small, and the height of the overload prevention locking teeth also becomes the stroke of the disc spring. Since it becomes a small thing collectively, in order to give the precision to the height of a locking tooth, machining etc. are required and it becomes high-cost. In addition, since the height of the locking tooth for preventing overload is low, if the manufacturing tolerance is the same, the ratio of the manufacturing tolerance error to the tooth height is larger than that of the tooth having a high locking tooth height. Therefore, the variation in slip load becomes large, and the quality stability of the product is impaired. In addition, it is necessary to keep the slip load within a certain range when the hoisting machine is shipped. However, since the stroke is small, it is easily affected by the error of the spring pressure due to the accumulated dimensional error of related parts. It was necessary to adjust the spring pressure, and the adjustment range became very small, making adjustment difficult and skilled.

  In addition, as an overload prevention device in a hoisting machine that solves the above-mentioned problems by using an elastic member having a large stroke without increasing the hoisting device, a drive shaft for driving a load sheave in the present applicant; , A pressure receiving member externally mounted on the drive shaft, a drive member that transmits the driving force from the hand wheel to the drive shaft through the pressure receiving member, and a driving force from the hand wheel to the driving member, and a predetermined torque on the hand wheel A rotation drive member having means for releasing the engagement with the drive member when a torque greater than the value is applied, and between the back surface of the rotation drive member and the inner end face of the handwheel along the axial direction of the drive member An overload prevention device has been developed that includes a plurality of elastic members that are mounted and bias the rotational drive member.

  However, in the overload prevention device, the rotation drive member is biased by a plurality of springs arranged along the axial direction of the drive member, so that the spring pressure received by the rotation drive member becomes non-uniform. At the time of overload, the rotation driving member is easily inclined, and the inclination causes a problem that the rotation driving member interferes with the guide portion on the inner periphery of the handwheel and the movement in the axial direction cannot be smoothly performed. In addition, since the inner end surface of the handwheel is directly pressed by the spring, a frictional resistance is generated between the handwheel and the sliding surface of the washer that locks the handwheel and the driving member, and the accuracy of the washer is not necessarily Since it is not constant, there is a problem that the slip load between the rotary drive member and the drive member during overload is not constant.

  The present invention solves the above-described problem, and is a rotary drive device in a hoisting machine that includes an overload prevention means that engages with the inner periphery of the operating means of the hoisting machine and transmits the drive of the operating means to the driving member. The rotary drive device includes an annular link, and a plurality of horizontally long projections extending in the axial direction of the drive member from the outer periphery of the annular link and fitted in the inner periphery and the width direction of the operating means, An overload-preventing engagement tooth that meshes with an engagement tooth provided on the drive member is provided only on the drive member side end of the protrusion.

  Further, the engagement tooth of the rotational drive device for preventing overload is provided at the end of the protrusion on the drive member side so as to protrude from the end face of the annular link.

  Further, the annular link is formed thin with respect to the length of the horizontally long projection.

  The rotary drive device in the hoisting machine of the present invention is provided with an annular link and a plurality of horizontally elongated projections that protrude from the outer periphery of the annular link in the axial direction of the drive member and extend in the width direction with the inner periphery of the operating means. The overload-preventing engagement teeth provide power to the handwheel because the overload-prevention engagement teeth that mesh with the engagement teeth of the drive member are provided only on the drive-member-side end portions of the protrusions. Since it is provided just below the horizontally long projections to be transmitted, the strength of the overload prevention engaging teeth and the base where the engaging teeth are provided are compared with the conventional device without considering the downsizing of the part receiving the spring pressure. Can be strengthened and the durability can be greatly improved, and no overload prevention engagement teeth are provided directly under the annular link for receiving spring pressure. And when the engaging teeth get over the engaging teeth of the drive member The engagement receiving from engagement teeth securing strength to withstand the reaction force becomes unnecessary, can be made thin in comparison to annular link portion to the conventional apparatus, it is possible to suppress the axial dimension, compact, thereby enabling weight reduction. In addition, as a result of providing overload-preventing engagement teeth on the horizontally elongated protrusions and increasing the strength of the overload-prevention engagement teeth, the inclination angle of the inclined teeth of the engagement teeth can be increased. Since the sliding resistance for the combined teeth to get over the engaging teeth of the drive member can be set large, a spring having a small spring pressure can be used, and the size can be reduced.

  Moreover, since the height of the engagement tooth for overload prevention can be increased, the ratio of the manufacturing tolerance error to the height of the engagement tooth can be reduced, and the occurrence of slip load variation can be suppressed. Adjustment at the time of shipment of the hoisting machine can be made unnecessary.

  Furthermore, by increasing the height of the protruding portion of the horizontally long protrusion and increasing the engagement with the operating means, the tilting operation does not occur when the operating means is operated, and the operating means can be smoothly fitted and moved. Furthermore, since the rotary drive device does not come into contact with the operation means, the frictional resistance is small and the operational stability can be improved.

  Hereinafter, embodiments of the present invention will be described.

  A hoisting machine according to an embodiment of the present invention will be described with reference to FIGS. 1 is a front view of a hoisting machine according to an embodiment of the present invention, FIG. 2 is an enlarged view of a main part of the overload prevention device of FIG. 1, FIG. 3 is an exploded perspective view of FIG. 5 is a cross-sectional view taken along the line AA in FIG. 4, FIG. 6 is a front view of the drive member in FIG. 2, FIG. 7 is a plan view in FIG. 6, and FIG. 9 is a front view of the rotary drive member of FIG. 2, FIG. 10 is a bottom view of FIG. 9, FIG. 11 is a perspective view of the fitting convex portion of FIG. 9, and FIG. FIG. 13 is a front view of the spring presser of FIG. 2, and FIG. 14 is a cross-sectional view taken along line AA of FIG. 13.

  In the figure, 1 is a load sheave, 2 is a drive shaft rotatably supported by the load sheave 1, 2a is a fitting portion with the pressure receiving member 4, 3a is engaged with a gear provided at the tip of the drive shaft 2, A reduction gear 3 for reducing the rotation is engaged with a small gear (not shown) integrated with the reduction gear 3a, and a load gear for rotating the load sheave 1, 4 is a pressure receiving member, 4a is a boss portion of the pressure receiving member, and 5 is reverse rotation. The prevention wheel, 6 is a claw for controlling the reverse rotation prevention wheel 5 to rotate in one direction, 7 is a spring for urging the claw 6, 8 is a brake plate, 9 is a hand wheel as an operating means, The inner recess 9a into which the horizontally long projection 11b of the rotary drive member 11 is fitted, the inner end face 9d with which the end faces of the drive member 10 and the spring retainer 13 are in contact, and the guide portion 10g of the drive member 10 And sliding contact with the guide portion 13c of the spring presser 13 That includes an annular guide portion 9e. Reference numeral 10 denotes a driving member, and reference numeral 10a denotes a female screw portion of the driving member, which is screwed with the pressure receiving member 4. Reference numeral 10b denotes a flange portion of the drive member 10, which has an outer diameter larger than the inner diameter of the handwheel 9, and has an end surface in a disk shape. Reference numeral 10c denotes a boss part into which the rotational drive member 11 and the spring 12 are inserted, and reference numeral 10d denotes engagement teeth formed on the handwheel side disk surface of the flange part 10b, and the shape thereof prevents overload of the rotational drive member 11 to be described later. The engaging teeth 11a for use are in close contact. The engaging tooth 10d has a locking tooth portion 10j having a steep slope in a substantially right angle direction and an inclined tooth portion 10k having a gentle slope. 10e is a thread groove into which a spring retainer 13 to be described later is screwed, 10f is a positioning locking step portion with which the spring retainer abuts, 10g is an outer peripheral surface of the flange 10b, and is slidably contacted with the guide portion 9e of the handwheel 9. 10h is a fan-shaped opening, and 10i is an end. A rotation restricting member 14 fixed to the end of the drive shaft 2 is inserted into the opening 10h, and the opening 10h of the drive member 10 is rotated when the drive member 10 is rotated in the loosening direction of the screw by the female screw 10a. The end portion 10i is in contact with the rotation restricting member 14 to restrict the rotation, and the drive member 10 is prevented from being loosened too much.

  In normal times, the end 10i of the opening 10h of the drive member 10 and the rotation restricting member 14 are provided with a predetermined interval in the rotation direction. Reference numeral 11 denotes a rotational drive member that fits into the boss portion 10c of the drive member 10, and the annular link portion 11e and the outer periphery of the annular link portion 11e are fitted to the fitting recess 9a of the handwheel 9 in the width direction. The drive member 10 is provided with a fitting protrusion 11b which is a horizontally long protrusion extending in the axial direction of the drive member 10, and the drive member 10 is provided on the drive member 10 side of the horizontally long protrusion 11b from the drive member 10 side end surface of the rotation drive member 11. An overload-preventing locking tooth 11 a that protrudes to the side and meshes with the engaging tooth 10 d of the driving member 10 is provided. The overload-preventing locking tooth 11a has a locking tooth portion 11c having a steep slope in a substantially right angle direction that acts when the load is lowered, and an inclined tooth portion 11d having a gentle slope that acts when the load is lifted.

  In this embodiment, the rotary drive member 11 can move in the axial direction of the drive member 10 along the fitting recess 9 a of the handwheel 9 against the biasing force of the spring 12 described later. As shown in FIG. 9, the thickness of the link portion 11e is formed relatively thin with respect to the axial length h of the projection 11b, and the projection 11b connects the rotary drive member 11 to the handwheel 9 as shown in FIG. On the other hand, a sufficient engagement length is ensured to engage with each other so that the movement can be transmitted without tilting. Four protrusions 11b are provided on the outer periphery of the annular link portion 11e of the rotation drive member 11, and the handwheel 9 is provided with four fitting recesses 9a. This number is not limited to four. Further, a gap for reducing friction is provided between the outer periphery of the protrusion 11 b and the fitting recess 9 a of the handwheel 9. A spring 12 urges the rotary drive member 11 toward the drive member 10. The spring 12 includes an inner spring 12 a and an outer spring 12 b, and is wound around the boss portion 10 c of the drive member 10. It is disposed in the space between the inner inner periphery 9 c of the wheel and between the rotation drive member 11 and the spring retainer 13. Reference numeral 13 denotes a spring retainer, a screw portion 13a that is screwed into the screw groove 10e of the drive member 10, a contact surface 13b that comes into contact with the locking step portion 10f of the drive member 10 when screwed to the drive member 10, and an outer periphery. It has a guide portion 13 c that has an outer diameter larger than the inner diameter of the handwheel 9 and that is in sliding contact with the annular guide portion 9 e of the handwheel 9. Reference numeral 14 denotes a rotation restricting member fixed to the end of the drive shaft 2 and fitted into the opening of the drive member 10. The hoisting machine is driven and braked by a so-called mechanical brake including a driving member 10, a pressure receiving member 4, a reverse rotation preventing wheel 5, and a brake plate 8 connected to the handwheel 9 via a rotation driving member 11. .

  As described above, the handwheel 9 is provided with a space 9f having a length substantially the same as the width of the inner periphery 9c of the handwheel 1 between the inner peripheral surface 9c and the outer periphery of the drive member 10. In this space 9f, the drive member 10 and the handwheel 9 are engaged with each other, and the rotation drive member 11 that transmits the drive of the handwheel 9 to the drive member 10 and the boss portion 10c of the drive member 10 are wound around and rotated. A spring member 12 that presses the member 11 toward the drive member 10 and a spring retainer 13 that is screwed into the screw groove 10e of the drive member 10 and holds the spring member 12 are provided.

  Further, the drive member 10 is provided with a step portion 10f for restricting the movement of the spring retainer 13 toward the rotational drive member 11 side, and the spring retainer 13 is screwed into the screw groove 10e of the drive member 10 so that the step is provided. In this state, the guide portion 13c on the outer periphery of the spring presser 13 is configured to be in sliding contact with the annular guide 9e of the handwheel 9 to guide the rotation of the handwheel 9. The guide portion 10 g of the drive member 10 is configured to slide in contact with the annular guide 9 e on the drive member 10 side of the handwheel 9 to guide the rotation of the handwheel 9. Thus, the annular guide 9e of the handwheel 9 is slidably contacted with the guide portion 13c of the spring retainer 13 and the guide portion 10g of the drive member 10, and is supported by these guide portions. The spring member 12 wound around the drive member 10 includes a small-diameter coil spring 12a and a large-diameter coil spring 12b, and between the drive member 10 and the inner periphery 9c of the handwheel 9, between the rotary drive member 11 and the spring retainer 13. It is stretched in a cylindrical space extending straight in the axial direction. A female screw 10 a is screwed inside the driving member 10, and the female screw 10 a is screwed to a screw provided on the outer periphery of the pressure receiving member 4. A brake plate 8 is provided on the outer periphery of the pressure receiving member 4 so as to be coaxially rotatable. The brake plate 8 is a pair between the pressure receiving portion formed at one end of the pressure receiving member 4 and the driving member 10, and is attached to the pressure receiving member 4. On the other hand, it is rotatably provided. An anti-reverse wheel 5 is provided between the brake plates 8 and 8 on the outer circumference coaxial with the pressure receiving member 4.

Reference numeral 18 denotes a frame body of the hoisting machine, which is formed by die casting using an aluminum alloy or lost wax casting.
As shown in FIG. 1, the frame body 18 includes a drive side frame 18a and a deceleration side frame 18b, and a connection frame 18c that connects and couples both, and the frames 18a and 18b project to the drive side and the deceleration side, respectively. The driving side cover 20a and the reduction gear side cover 20b are attached in close contact with the outer peripheral edge portion. An opening 19a facing the drive side is formed in the drive side overhanging portion of the drive side frame 18a, and the pressure receiving member 4, the brake plate 8, the reverse rotation preventing wheel 5, the claw 6, and the spring 7 are accommodated in the opening 19a. Is done. An annular groove 19b into which the handwheel 9 is fitted is provided at a side end portion of the driving side frame 18a. The annular groove 19b has an annular groove even when the handwheel 9 is moved in the axial direction by a mechanical brake. A sufficient axial space 19c in which the handwheel is fitted in the groove 19b is provided in advance.

  With this configuration, the pressure receiving member 4, the brake plate 8, the anti-reverse wheel 5, the claw 6, and the spring 7 that are accommodated in the opening 19 a have the handwheel 9 in the annular groove 19 b provided at the side end of the drive side frame 18 a. Since it is sealed from the outside by being mounted, it is possible to prevent dust from entering from the outside, and it is possible to prevent performance degradation of the mechanical brake and the overload prevention device due to dust.

  18d and 18e are fixed to the inside of the connecting frame 18c, and can improve the wear resistance of the bearing plate for rotatably supporting the load sheave 1 and the bearing portion of the load sheave 1 by die casting. By using an aluminum alloy, the wear resistance is not lowered, and thus the weight can be reduced.

  Next, the driving force switching operation according to the present embodiment will be described. During normal operation, the rotation of the handwheel 9 is transmitted to the drive shaft 2 through the rotation drive member 11, the drive member 10, and the pressure receiving member 4, and is decelerated from the drive shaft 2 by the reduction gear 3a and the load gear 3b. Drives the load sheave 1 at a reduced speed.

  Next, the configuration and operation of the overload prevention device that operates during overload will be described. The handwheel 9 includes a coil spring 12, a rotation drive member 11, and a drive member 10. The spring 12 biases the rotation drive member 11 in the axial direction, that is, the drive member 10 side. Further, the rotation driving member 11 is connected so that the fitting convex portion 11b is fitted with the fitting concave portion 9a of the hand wheel 9, and can rotate integrally with the hand wheel 9 and can slide in the axial direction. The drive member 10 can rotate following the rotation of the rotary drive member 11 when the engagement tooth 10d of the drive member 10 meshes with the overload-preventing engagement tooth 11a of the rotary drive member 11. ing. That is, when the handwheel 9 is operated to rotate the rotation drive member 11, the drive member 10 is rotated via the overload prevention engagement teeth 11 a of the rotation drive member 11 and the engagement teeth 10 d of the drive member 10. Then, the drive member 10 presses and rotates the pressure receiving member 4, and the pressure receiving member 4 rotates to rotate the drive shaft 2, and the load sheave 1 is moved from the drive shaft 2 through the reduction gear 3a and the load gear 3b. Rotates and rolls up the load.

  When the load is lifted in an overload state and the handwheel 9 and the rotation drive member 11 are rotated in a state where a torque of a predetermined value or more is applied to the handwheel during the hoisting operation of the load, the engagement teeth of the drive member 10 are obtained. The inclined tooth portion 11d of the rotary drive member 11 meshing with 10d slides the inclined tooth portion 10k engaging surface of the engaging tooth 10d against the biasing force of the spring 12 and is pushed back in the axial direction to rotate. The engagement tooth 11a for preventing overload of the drive member 11 gets over the engagement tooth 10d of the drive member 10 and meshes with the next engagement tooth 10d of the drive member 10 by the biasing force of the spring 12, and in the overload state Since the operation of overriding the engagement tooth 10d of the drive member 10 by the overload prevention engagement tooth 11a of the rotation drive member 11 is continuously performed, the drive is not transmitted from the rotation drive member 11 to the drive member 10.

  Thus, in the overload state, when the handwheel 9 is rotated in the winding direction, the rotation drive member 11 rotates, but the overload prevention engagement teeth 11 a of the rotation drive member 11 are engaged with the drive member 10. Since the tooth 10d is slid to get over and idle, the rotation of the rotary drive member 11 is not transmitted to the drive member 10, and the winding operation at the time of overload is prevented.

  The rotary drive device in the hoisting machine of the present invention is fitted with an annular link 11e and a fitting recess 9a provided on the inner circumference of the handwheel 9 that protrudes from the outer circumference of the annular link 11e in the axial direction of the drive member 10. And a plurality of horizontally long fitting protrusions 11b, and an engagement tooth 11a for preventing overload that engages with an engagement tooth 10d of the driving member 10 at an end portion on the driving member directly below the fitting protrusion 11b. And the overload preventing engagement teeth 11a are provided at the end of the horizontally long fitting convex portion 11b, so that the strength of the overload preventing engagement teeth 11a can be enhanced as compared with the conventional device. In addition, since the durability can be significantly improved and the engagement teeth for preventing overload are not provided in the annular link portion 11e, the engagement teeth are engaged with the engagement teeth of the drive member at the time of overload. Withstands the reaction force received from the engaging teeth when getting over Securing the strength becomes unnecessary, the annular link portion 11e can be made thin in comparison with the conventional device, compact, thereby enabling weight reduction. Further, as a result of providing the load-preventing engagement teeth 11a on the horizontally long fitting projection 11b and increasing the strength of the engagement teeth 11a, the inclination angle of the inclined teeth of the engagement teeth 11a can be increased, and the engagement teeth 11a Therefore, it is possible to use a spring having a small spring pressure and to reduce the size.

  Further, since the height of the overload preventing engagement teeth 11a can be increased, the ratio of the manufacturing tolerance error to the height of the overload preventing engagement teeth 11a can be reduced, and the occurrence of slip load variation can be reduced. Therefore, adjustment at the time of shipment of the hoisting machine can be made unnecessary.

  Further, by increasing the height of the protrusion of the horizontally long fitting projection 11b and increasing the engagement with the handwheel 9, the rotational drive member does not tilt when the handwheel 9 is operated, and the hand The rotary drive member 11 can be smoothly moved by being fitted to the wheel 9, and the rotational drive member 11 does not come into contact with the handwheel 9, so that the frictional resistance is small and the operation stability can be improved.

  In the rotary drive device of the hoisting machine according to the present invention, the engagement teeth for preventing overloading are provided at the ends of the horizontally long protrusions protruding from the outer periphery of the annular link, so that the durability of the engagement teeth can be improved and Since the link can be made thin, it is particularly suitable for a small hoisting machine.

The front view of the winding machine of this invention. The principal part enlarged view of the overload prevention apparatus of FIG. FIG. 3 is an exploded perspective view of FIG. 2. The front view of the handwheel of FIG. AA sectional drawing of FIG. The front view of the drive member of FIG. The top view of FIG. AA sectional drawing of FIG. The front view of the rotation drive member of FIG. The bottom view of FIG. The fitting convex part side perspective view of FIG. The overload prevention engagement tooth side perspective view. The front view of the spring retainer of FIG. AA sectional drawing of FIG. The front view of the conventional mounting machine. The disassembled perspective view which shows the principal part of the overload prevention apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Load sheave 2 Drive shaft 2a Fitting part 2b Idle part 2c Engagement part 2d Screw part 3a Reduction gear 3b Road gear 4 Pressure receiving member 4a Boss part 5 Reverse rotation prevention wheel 6 Claw 7 Spring 8 Brake plate 9 Hand wheel 9a Fitting recessed part 9b Insertion groove 9c Inner inner periphery 9d Inner peripheral end surface 9e Annular guide portion 9f Space 10 Drive member 10a Female screw 10b Flange 10c Boss portion 10d Engagement tooth 10e Screw groove 10f Locking step portion 10g Guide portion 10h Opening portion 10i End portion 10j Locking Tooth part 10k Inclined tooth part 11 Rotation drive member 11a Overload prevention engaging tooth 11b Fitting convex part 11c Locking tooth part 11d Inclining tooth part 11e Annular link part 12 Spring 12a Inner spring 12b Outer spring 12c Fitting convex part 13 Spring retainer 13a Screw part 13b Abutting part 13c Guide part 14 Rotation restricting member 15 Upper foot 16 Load chain 17 Hand chain 18 Frame body 18a Drive side frame 18b Deceleration side frame 18c Connection frame 18d, 18e Bearing plate 19a Opening 19b Annular groove 19c Space 20a Drive side cover 20b Reduction gear side cover

Claims (3)

  A rotary drive device in a hoisting machine that includes an overload preventing means that engages with an inner periphery of an operating means of a hoisting machine and transmits the drive of the operating means to a driving member, the rotary driving apparatus comprising an annular link And a plurality of horizontally long protrusions that protrude from the outer periphery of the annular link in the axial direction of the drive member and fit in the inner periphery and the width direction of the operating means, and are driven only at the end of the protrusion on the drive member side. An overload-preventing engaging tooth that meshes with an engaging tooth provided on a member is provided.   2. The rotary drive device for a hoisting machine according to claim 1, wherein the overload preventing engagement teeth are provided so as to protrude from the end face of the annular link at the end of the protrusion on the drive member side.   The rotary drive device for a hoist according to claim 1 or 2, wherein the annular link is formed thin with respect to the length of the horizontally long protrusion.