JP2725230B2 - Chain lever hoist - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chain lever hoist using a load chain (hereinafter referred to as "lever hoist") which can hoist, unwind or tow an article by manually operating a lever. It is about.

[0002]

2. Description of the Related Art Generally, in this type of lever hoist,
In addition to the operation of lifting and lowering the load chain by lever operation (hereinafter referred to as "winding operation"), it is essential that the chain can freely move under no load, that is, the so-called idle operation of the load sheave. It is a condition.

[0003] Among the conventional lever hoists, the structure of a lever hoist which is currently in the mainstream includes a main frame, a load sheave rotatably mounted on the main frame, and a rotation interlocking with the load sheave. A spindle attached to the main frame, a fixed friction plate fixed to the spindle, a hub screwed to the spindle and rotated by a lever swinging around the spindle,
A ratchet gear and a brake lining loosely fitted to the spindle between the fixed friction plate and the hub; and a ratchet pawl attached to a main frame so as to mesh with the ratchet gear, and rotating the hub. By changing the distance between the fixed friction plate and the hub, the ratchet gear and the brake lining can be loosened freely. There is known a spring-type lever hoist in which a spring is pushed outward by the force of a coil spring to reduce the contact pressure of the hub with the brake lining, that is, to loosen the brake. To explain the operation, during the hoisting operation, when the lever is swung in the hoisting direction, the hub is screwed into the spindle by the torque due to the hanging load, and the ratchet gear and the brake are fixed by the hub and the fixed friction plate. Since the lining is tightened, the torque of the lever is transmitted from the hub to the ratchet gear, brake lining, fixed friction plate, spindle, and load sheave, and the ratchet gear rotates while riding on the ratchet pawl, causing the load sheave to rotate in the hoisting direction. , The goods are hoisted. On the other hand, during the unwinding operation, the hub is screwed into the spindle by the torque caused by the hanging load, and the ratchet gear and the brake lining are tightened by the hub and the fixed friction plate. During the swinging, the tightening force is slightly relaxed by the lever torque during the swinging, so that the ratchet gear and the brake lining and the fixed friction plate slide appropriately, and the load sheave moves to the hub. Is rotated in the unwinding direction in accordance with the rotation of the object, and the article is unwound. In the idle operation, when the connection between the lever and the hub is cut off and the hub is rotated to leave an interval between the fixed friction plate and the hub, the contact pressure of the hub with the ratchet gear and the brake lining is relaxed, and the coil spring With this force, the hub is pushed outward, so that the brake does not work and the load sheave can idle. And, JP
Japanese Unexamined Patent Publication No. 5-2570 also discloses a spring-type lever hoist of this kind.
Are disclosed . This is the drive
A holding member fixed to the outer end of the
The base end of the elastic resistance member consisting of a spring is fixed, and the switching gear
An arcuate engagement member is provided on the side of the
A member connected to the body and part of the periphery of the holding member
The stop projection is formed around the space formed by the adjacent engaging members.
Insert freely in the surrounding direction and engage the tip of the elastic resistance member
It is arranged to face the circumferential end of the member.
You. The operation is performed by rotating the drive shaft forward (arrow A in the publication).
Direction), the elastic resistance member is positioned at the circumferential end of the engagement member.
Drive unit by the elastic force of the elastic resistance member.
Relative rotation between the material and the driven member (pressing the drive member
Relative rotation that reduces the distance from the driven member).
To prevent the tightening of the brake part
(See page 9, lower left column, line 9 to lower right column, line 7,
See). That is, in this configuration, the plate which is the elastic resistance member
The spring performs exactly the same function as the previous coil spring
Because of this leaf spring, the driving member and the driven
Resistance force repelling against relative rotation with the member always acts
However, idle rotation always occurs when there is no load.
You.

[0004] In this type of lever hoist, in many models for a weight exceeding 0.5 ton, the load sheave and the spindle are connected via a plurality of reduction gears. In general, the lightweight model has a structure in which the load sheave and the spindle are directly connected.

[0005]

However, in the above-mentioned conventional spring-type lever hoist, when the chain is moved quickly during the idle movement of the load sheave, only the spindle rotates and the rotation of the hub does not follow it. When the spindle is screwed into the hub, the distance between the fixed friction plate and the hub is reduced, and the brake is applied. For this reason, there has been a problem that the operation of turning the hub by hand each time to widen the space between the fixed friction plate and the hub and thereby releasing the brake must be repeated.

Further, in the conventional spring-type lever hoist, when a lightweight article is to be unwound, the force of screwing the spindle into the hub is weak because the article is lightweight, and this causes the coil spring or the coil spring to push the hub outward. When the spring force is smaller than the leaf spring force, the brake spring is vigorously lowered in a state where the brake is not applied, resulting in a fatal problem that an unexpected accident is caused.

That is, in the conventional spring-type lever hoist, if the spring force of the coil spring or the leaf spring is increased, the idle operation can be easily ensured, but a light-weight object is liable to fall, which is dangerous. If the weight of the chain is weakened, the fall of the lightweight object can be prevented. However, if the chain is operated quickly in the idle operation, there is a conflicting problem that the brake is applied immediately and the movement of the chain is inconvenient.

[0008] In addition, as a mechanism for causing the load sheave to idle, for example, in the above-described lever hoist with a reduction gear, the shaft of the reduction gear is slid to cut off the connection of the gears, so that the load sheave is connected. There are a type in which the idle operation is performed, and a type in which the ratchet pawl is detached from the ratchet gear, and the load sheave is idled by removing the ratchet pawl. If these mechanisms are used, the above-mentioned problems are unlikely to occur, but all of them are complicated mechanisms, so that operability is poor and sometimes they do not operate smoothly, or they are easy to break down and lack reliability. . In addition, when shifting from the idle operation to the winding operation, one action is always required.

The present inventor has conducted experiments to solve the above problems.
As a result of repeated research, the idle rotation of the lever hoist
Focusing on what is obtained by associating the spindle and the hub so that they rotate together without brakes applied, turning the hub or spindle by a small angle by hand causes the screw of the hub to the spindle to rotate. The engagement position is set in a state where the contact pressure of the hub and the fixed friction plate does not act on the ratchet gear and the brake lining, and by holding this state so that it does not return, the idle movement of the load sheave can be performed with a simple mechanism. The purpose is to secure them, and to solve the above-mentioned problems at once.

[0010]

As means for achieving this object, a main frame, a load sheave rotatably attached to the main frame, and the main frame so as to rotate in conjunction with the load sheave. An attached spindle, a fixed friction plate fixed to the spindle, a hub screwed to the spindle and rotated by a lever swinging around the spindle, and a hub between the fixed friction plate and the hub. A ratchet gear and a brake lining that are loosely fitted to the spindle; a ratchet claw attached to the main frame so as to mesh with the ratchet gear; with screwed position when shifted to the position at the time of operation and a positioning mechanism for holding so as not irreversible, the lock operation Celtic positioning mechanism is actuated unload
The positioning mechanism becomes inoperable when receiving a lock operation.
Configured. Here, the lock operation means that the lever is connected to the hub.
Break the linkage and screw the hub onto the spindle.
Shift the position from the position during winding operation to the position during idle rotation operation
Refers to operations. In addition, unlock operation means lever and hub
Leverage the link between the hub and the spindle of the hub.
From the position during idle rotation to the position during winding operation.
This refers to the shifting operation. Furthermore, the positioning mechanism has a temporarily fixed
There are two types, fixed and fixed, where
Is limited by the torque applied to the hub and spindle
When the value is less than or equal to the value, the two are connected, but the value exceeds the limit.
Then, the connected state is released. Also, fixed is
Unless the hub and spindle are released, the connection
It means being in charge. In the temporarily fixed positioning mechanism,
The unlock operation includes operations that can be performed by lever operation.
included.

[0011]

The lever hoist having the above-described structure can be used at the time of hoisting operation.
If the lever is swung and the hub is turned in the hoisting direction, the hub is screwed into the spindle by the torque due to the hanging load, the ratchet gear and brake lining are tightened with the hub and the fixed friction plate, and When the hub is turned in the hoisting direction, the torque of the lever is transmitted from the hub to the ratchet gear, brake lining, fixed friction plate, spindle, load sheave, and the ratchet gear is loaded by rotating while riding on the ratchet pawl. The sheave rotates in the hoisting direction. On the other hand, during the unwinding operation, the hub is screwed into the spindle by the torque due to the hanging load, and the ratchet gear and the brake lining are tightened by the hub and the fixed friction plate. In this direction, the tightening force is slightly relaxed by the lever torque during the rotation, so that the ratchet gear and the brake lining and the fixed friction plate slide appropriately, and the load sheave is moved. It rotates in the unwinding direction according to the rotation of the hub. Then, when you want the idle operation ,
Operation. That is , by turning the hub or spindle by a small angle by hand, the screwing position of the hub with respect to the spindle is slightly shifted from the position of the winding operation during the idle operation, that is, the contact pressure of the hub with the ratchet gear and the brake lining is reduced. then, positioned in the position where it does not act
The mechanism operates, and the screwing position is held by the positioning mechanism so as not to return to the original position . As a result, the relative position between the spindle and the hub is maintained in a state where the brake is not applied, so that the idle movement of the load sheave is ensured, and the brake does not operate even if the load sheave is rapidly rotated. Also, when you want to perform the winding operation after the idle operation
Perform unlock operation. In other words, the hub spindle
Return the engaged screw position from the idle operation position to the winding operation position
And the positioning mechanism becomes inoperative . Then, always hub and a coil spring urging outward like a conventional spring lever hoist, always reverse et al tightening direction of rotation of the hub
Since there is no member such as a leaf spring to exhibit elasticity ,
The contact pressure of the hub against the ratchet gear and the brake lining is reliably ensured.

[0012]

1 to 5 show a first embodiment. 1 and 2, 1 is a main frame, 2 is a load sheave rotatably attached to the main frame 1, 3 is a load chain engaged with the load sheave 2, and 4 is rotatably attached to the main frame 1. A spindle gear 4b at one end, the spindle gear 4b meshing with the gear 2a of the load sheave 2 via a reduction gear group G, and a threaded portion 4a at the other end side. ing. Reference numeral 5 denotes a disk-shaped hub having a female threaded hole in the center, and the screw portion 4a of the spindle 4 is screwed into this hole. The hub 5 integrally has a friction plate 5b and a switching gear 5a, and has a projection 5c protruding on an outer surface. here,
The outer peripheral portion of the hub 5 functions as a knob for putting a hand when turning the hub 5 by hand, but the knob may be attached to the outer peripheral side of the hub 5 separately from the hub 5. Reference numeral 6 denotes a fixed friction plate fixed to the spindle 4. The friction plate 5b
Between the fixed friction plate 6 and the ratchet gear 7;
One or a plurality of brake linings 8 are mounted on the spindle 4 in a loosely fitted state, and the hub 5 is turned by hand to change the distance between the fixed friction plate 6 and the hub 5 so that the ratchet gear 7 and the brake The lining 8 can be loosened freely.

In FIG. 1, reference numeral 7a denotes a pair of ratchet pawls mounted on the main frame 1 and meshing with the ratchet gear 7, and 9 denotes a lever provided to swing about the spindle 4. Reference numeral 10 denotes a knob for switching between the winding operation and the idle operation, which is rotatably provided on the lever 9 and has a switching gear 5a of the hub 5 at its inner end.
And has a U-shaped switching claw 10a that meshes with the switch. Reference numeral 11 denotes a leaf spring which constitutes a positioning mechanism together with the protrusion 5c. The leaf spring 11 is fixed to the spindle 4, and is formed in a fan shape as viewed from the spindle rotation center as shown in FIG. . In FIG. 2, the screwing position of the hub 5 with respect to the spindle 4 is at the time of the winding operation.
In other words, the hub 5 is turned clockwise and screwed into the spindle 4.
c is in pressure contact with the leaf spring 11, and the projection 5c is
It is possible to move while sliding. In FIG. 3, the screwing position of the hub 5 with respect to the spindle 4 is at the position during the idle operation slightly deviated from the position during the winding operation. That is, the hub 5 is shifted counterclockwise by a small angle and is held so that the screwing position does not return to its original position. As shown in FIG. It is temporarily fixed so as to hang on the edge in the counterclockwise direction and not to rotate further in the clockwise direction. However,
It is possible to turn counterclockwise. Here, the term “temporarily fixed” means that the hub 5 and the spindle 4 are connected when the torque applied to them is equal to or less than the limit value, but the connection state is released when the torque exceeds the limit value.

Next, the operation of the lever hoist having the above structure will be described. At the time of the hoisting operation, the knob 10 is tilted clockwise in FIG. 2, the left end of the switching claw 10a is bitten by the switching gear 5a, and the lever 9 is swung clockwise, whereby the torque due to the hanging load causes Hub 5
Is screwed into the spindle 4 and the ratchet gear 7 and the brake lining 8 are formed by the hub 5 and the fixed friction plate 6.
Tighten. At this time, the protrusion 5c is in pressure contact with the leaf spring 11 as shown in FIGS. Further, when the lever 9 is repeatedly swung clockwise, the lever 9
Is transmitted from the hub 5 to the ratchet gear 7, the brake lining 8, the fixed friction plate 6, the spindle 4, and the load sheave 2, and the ratchet gear 7
By rotating while riding on a, the load sheave 2 rotates in the hoisting direction to hoist the load chain 3.

On the other hand, at the time of the unwinding operation, if the knob 10 is tilted counterclockwise in FIG. 2 and the right end of the switching claw 10a is engaged with the switching gear 5a, the hub 5 is rotated by the torque caused by the suspension load. 4, the ratchet gear 7 and the brake lining 8 are tightened by the hub 5 and the fixed friction plate 6. Also at this time, the protrusion 5c is in pressure contact with the leaf spring 11. Further, when the lever 9 is repeatedly rocked in the counterclockwise direction, the tightening force is slightly relaxed by the torque of the lever 9 during the rocking, so that the fixed friction plate 6 and the ratchet gear 7 are rotated. And the brake lining 8 slides moderately, and the load sheave 2 rotates to lower the load chain 3.

When the idle operation is desired, the lock operation is performed.
Do the work. That is , the left and right load chains 3 hanging from the load sheave 2 are grasped by hand, and as shown in FIG. 3, the knob 10 is set to the neutral position and the switching claw 10a is set.
When the hub 5 is separated from the switching gear 5a and the hub 5 is turned counterclockwise by a small angle by hand, positioning is performed when the screwing position of the hub 5 with respect to the spindle 4 is set to a position in the idle operation slightly deviated from the winding operation position. The mechanism operates, and the screwing position is temporarily fixed by the position determining mechanism so as not to return to the original position. That is, as shown in FIGS. 3 and 5, the protrusion 5 c comes off the leaf spring 11 and abuts on its counterclockwise edge,
Since it does not rotate further clockwise, the relative position between the spindle 4 and the hub 5 is maintained in a state where the contact pressure of the hub 5 with respect to the ratchet gear 7 and the brake lining 8 is not applied, and the brake is not applied. Therefore, the idle operation of the load sheave 2 is ensured, and even if the load sheave 2 is rapidly rotated, the brake does not work.

When shifting from the idle operation to the hoisting operation,
Perform unlock operation. That is, if the knob 10 is tilted clockwise and the left end of the switching claw 10a is engaged with the switching gear 5a, and the lever 9 is swung clockwise, the torque of the lever 9 is prevented by the leaf spring 11 from moving the projection 5c. since it and outweighed force to the projections 5c pushes up the plate spring 11 around hub 5 in a clockwise direction, the temporary fixing is released ready in Figure 2, the positioning mechanism becomes inoperative, as it is immediately A hoisting operation is obtained.

Further, when the positioning mechanism becomes inoperative and the temporary fixing is released, a coil spring that constantly pushes the hub outward like a conventional spring-type lever hoist is used.
And exerts an elastic force that always opposes the tightening rotation direction of the hub.
Since there is no member such as a leaf spring, the contact pressure of the hub 5 against the ratchet gear 7 and the brake lining 8 can be ensured, so that a crash accident due to the inoperative brake during the unwinding operation of the lightweight article can be eliminated.

Further, since the structure is much simpler than those of the type in which the shaft of the reduction gear is slid as described above and the type in which the ratchet pawl is removed from the ratchet gear, it is easy to manufacture. If an indicator is provided so that the relative position between the hub 5 and the spindle 4 can be determined, it can be confirmed whether or not the idle operation is possible. Moreover, even if the brake lining 8 is worn, the screwing position of the hub 5 with the spindle 4 during the idle operation does not change.

Next, second to eleventh embodiments will be described. Each embodiment differs from the first embodiment only in the configuration of the positioning mechanism. First, FIG. 6 shows a second embodiment. In the first embodiment, the leaf spring 11 is formed in a fan shape as viewed from the center of rotation of the spindle, but in the second embodiment, the leaf spring 11 'is formed in a substantially disk shape, and one of the leaf springs 11' extends radially from the center of rotation of the spindle. The groove 11'a is notched. In FIG. 6, the screwing position of the hub 5 with respect to the spindle 4 is at the position at the time of the winding operation, and the hub 5 is screwed into the spindle 4 by turning the hub 5 clockwise. And the projection 5c can move while sliding on the leaf spring 11 '. And
Shift the hub 5 counterclockwise by a small angle and project
Is fitted into the groove 11'a of the leaf spring 11 ', the screwing position of the hub 5 with respect to the spindle 4 becomes the position at the time of the idle rotation operation, and is temporarily fixed so as not to rotate further clockwise,
The screwing position is held so as not to return to the original position.

FIGS. 7 and 8 show a third embodiment. Hub 5
Is provided with a concave portion 12 on the outer surface thereof, a disk 13 is fixed to the spindle 4 in the concave portion 12, a notch 13a is cut in the periphery of the disk 13, and a rod having a U-shaped convex curved portion 14a in the middle. One end of the spring 14 is fixed to the inner peripheral wall of the hub recess 12, and the elasticity of the bar spring 14 causes the convex curved portion 14 a to
3 is configured to be pressed against the periphery. In FIG. 7, the screwing position of the hub 5 with respect to the spindle 4 is the position at the time of the winding operation. That is, the hub 5 is turned clockwise and screwed into the spindle 4, and the convexly curved portion 14 a is pressed against the periphery of the disk 13. And in FIG.
The screwing position with respect to the spindle 4 is at a position at the time of idle rotation slightly deviated from the position at the time of winding operation. That is, the hub 5 is held counterclockwise by a small angle and held so that the screwing position does not return to the original position.
4a fits into the notch 13a of the disk 13 and is temporarily fixed so that it does not turn any more and does not turn further clockwise. Note that not only one end but also both ends of the bar spring may be fixed to the inner peripheral wall of the hub recess 12.

FIGS. 9 and 10 show a fourth embodiment. A concave portion 12 is provided on the outer surface of the hub 5, and a disk 13 ′ is fixed to the spindle 4 in the concave portion 12, and a pair of cylinders 15, 15 are fixed in the diameter direction of the disk 13 ′. A ball is embedded in the outer end of each cylinder 15,
A coil spring is mounted in each cylinder 15 in a contracted state. A pair of notches 16a, 16a are cut in the inner wall of the recess 12 in the diameter direction.
In FIG. 9, the screwing position of the hub 5 with respect to the spindle 4 is at the time of the winding operation. That is, the hub 5 is turned clockwise and screwed into the spindle 4. In this state, the ball of the cylinder 15 is pressed against the inner wall of the recess 12 of the hub 5. In FIG. 10, the screwing position of the hub 5 with respect to the spindle 4 is at the position of the idle operation slightly deviated from the position of the winding operation. That is, the hub 5 is turned counterclockwise by a small angle by hand, and the ball of the cylinder 15 is
6a, and is temporarily fixed so as not to rotate further clockwise. Incidentally, reference numeral 16b denotes a stopper, which defines a limit to which the hub 5 can rotate in the counterclockwise direction.

FIG. 11 shows a fifth embodiment. A recess 12 is provided on the outer surface of the hub 5, and a pair of arms 17, 17 are fixed to the spindle 4 in the recess 12 in the diametric direction. A pair of permanent magnets 18 are fixed to the inner wall of the recess 12 in the diameter direction. In FIG. 11, in the state of the imaginary line, the screwing position of the hub 5 with the spindle 4 is at the position during the winding operation, and the hub 5 is turned clockwise and screwed into the spindle 4. As shown by the solid line, when the hub 5 is shifted counterclockwise by a small angle and the permanent magnets 18, 18 adhere to the arms 17, 17, the screwing position of the hub 5 with respect to the spindle 4 becomes the position at the time of the idle operation. , The screw is temporarily fixed so as not to rotate further in the clockwise direction, and is held so that the screwed position does not return to the original position.

FIGS. 12 and 13 show a sixth embodiment. A pair of arms 21 and 21 are fixed to the spindle 4 in the diameter direction. A pair of holes 5e, 5e are provided in the outer surface of the hub 5 in the diametric direction, and after inserting the coil spring 23 into each of the holes 5e, the pin 22 is fitted so as to be freely retractable. 12 and 13, in the state of the imaginary line, the screwing position of the hub 5 with respect to the spindle 4 is at the position during the winding operation, and the hub 5 is turned clockwise and screwed into the spindle 4. Then, as shown by the solid line, the hub 5
When the pin 22 is moved counterclockwise by a small angle and the pin 22 passes under the arm 21 and comes out on the opposite side, the screwing position of the hub 5 with the spindle 4 becomes the position at the time of idle rotation, and It is temporarily fixed so that it does not turn in the direction, and is held so that the screwed position does not return to the original position.

FIGS. 14 and 15 show a seventh embodiment. On the outer surface of the hub 5, a pair of ridges 26, 2
6 are provided. The ridges 26 have a wedge-shaped cross section as shown in FIG. In addition, spindle 4
A disk-shaped lock plate 27 is provided so as to be movable in the spindle axis direction and bound in the rotational direction.
Are formed with concave portions 27a to be fitted with the above-mentioned convex stripes 26, 26. Further, the spindle 4 has a disk-shaped fixing plate 28.
Is fixed, and a coil spring 29 is compressed between the fixed plate 28 and the lock plate 27. In FIG. 14, in the state of the imaginary line, the screwing position of the hub 5 with the spindle 4 is at the position at the time of the winding operation, and the hub 5 is turned clockwise and screwed into the spindle 4. At this time, the lock plate 27 has its protruding portion 2
I am on 6,26. When the hub 5 is displaced counterclockwise by a small angle as shown by the solid line, the concave portion 27a of the lock plate 27 urged by the spring 29 fits into the ridges 26, 26 of the hub 5, and 5 spindles 4
Is temporarily fixed so as not to rotate further clockwise, and is held so as not to return to the original position.

FIGS. 16 and 17 show an eighth embodiment.
On the outer surface of the hub 5, the arm 4 is attached to the spindle 4.
And an elastic body 32, 3 such as rubber,
Fix 2 In the state of FIG.
Is in the position at the time of the winding operation, and the hub 5 is screwed into the spindle 4 by rotating the hub 5 clockwise. At this time, between the lower surfaces of the elastic bodies 32 and 32 and the outer surface of the hub 5 Has a gap. When the hub 5 is displaced in the counterclockwise direction by a small angle, the hub 5 comes up by the pitch screwed to the spindle 4, and the outer surface of the hub comes into contact with the elastic members 32, 32.
Under the pressing force of the spindles 2 and 32, the screwing position of the hub 5 with respect to the spindle 4 is temporarily fixed at the position at the time of the idle operation, and the screwing position is maintained so as not to return to the original position.

FIG. 18 shows a ninth embodiment. A concave portion 12 is provided on the outer surface of the hub 5, and the cam 36 is fixed to the spindle 4 in the concave portion 12, while the U-shaped convex curved portion 3 is provided halfway.
The both ends of the bar spring 37 having 7a are fixed to the inner peripheral wall of the hub concave portion 12, and the elasticity of the bar spring 37 causes the convex curved portion 37a.
Are adapted to be fitted to the nose of the cam 36. In the state of the imaginary line in FIG. 18, the screwing position of the hub 5 with the spindle 4 is at the position during the winding operation, and the hub 5 is turned clockwise and screwed into the spindle 4.
When the hub 5 is displaced in the counterclockwise direction by a small angle, the convexly curved portion 37a of the bar spring 37 is fitted to the nose of the cam 36 as shown by the solid line, and the screwing position of the hub 5 with respect to the spindle 4 is changed. It is temporarily fixed so as not to turn clockwise any more at the position at the time of idling operation, and is held so that the screwed position does not return to the original position.

FIGS. 19 and 20 show a tenth embodiment.
In the first to ninth embodiments, the holding by the positioning mechanism is temporarily fixed by a spring or the like, but the tenth and eleventh embodiments are not temporarily fixed but fixed. Here, “fixed” means that the hub 5 and the spindle 4 are in a connected relationship unless a releasing operation is performed. That is, 4
Reference numeral 1 denotes a cap which is spline-coupled so as to be movable only in the axial direction with respect to the spindle 4. Two holes 43, 43 are formed in the diameter direction. In FIG. 19, the screwing position of the hub 5 with respect to the spindle 4 is at the time of the winding operation. That is, the hub 5 is turned clockwise and screwed into the spindle 4, and the rods 42 are out of the holes 43. In FIG. 20, the screwing position of the hub 5 with respect to the spindle 4 is at the position during the idle operation slightly deviated from the position during the winding operation. That is, in a state where the hub 5 is shifted counterclockwise by a small angle and held so that the screwed position does not return to its original position, if the hub 5 is turned counterclockwise by a small angle by hand, the rod 42, 42 fit into the holes 43, 43,
The hub 5 does not rotate any more, and the hub 5 is fixed to the spindle 4. A coil spring (not shown) is mounted between the hub 5 and the cap 41, and always pulls the cap 41 toward the hub. This coil spring also functions as a torsion spring so as to always try to turn the cap 41 clockwise. Therefore, in order to escape from the idling operation shown in FIG.
Move to the winding operation of No. 9.

FIGS. 21 to 23 show an eleventh embodiment. While the fixing plate 46 is fixed to the spindle 4, an operation plate 49 with a knob is rotatably provided, and a pair of holes 5 e, 5 e are provided in the outer surface of the hub 5 in the diameter direction. And then insert stepped pin 4
7 is inserted so that it can come and go freely. The fixing plate 46 is provided with a hole 46a into which the tip of the stepped pin 47 can be fitted.
The operation plate 49 has a stepped pin 47 as shown in FIG.
An elongate hole 49a into which the tip of the is fitted is provided in the circumferential direction,
The periphery of the elongated hole 49a on the lower surface of the operation plate is inclined along the circumferential direction.
The shoulder of the step 7 is abutted to adjust the amount of protrusion of the stepped pin 47 from the hole 5e. In FIG. 21, in the state of the imaginary line, the screwing position of the hub 5 with the spindle 4 is at the position during the winding operation, and the hub 5 is turned clockwise and screwed into the spindle 4. Then, the knob-equipped operation plate 49 is rotated to maximize the amount of protrusion of the stepped pin 47 from the hole 5e, and then the hub 5 is shifted counterclockwise by a small angle as shown by the solid line in FIG. When the stepped pin 47 coincides with the hole 46a, the stepped pin 4
7 is fitted into the hole 46a by receiving the urging force of the coil spring 48, whereby the screwing position of the hub 5 with respect to the spindle 4 becomes the position at the time of idling operation, and is fixed so as not to rotate further clockwise. , So that the screwing position does not return to the original position. In this case, the release from the fixed state is achieved by rotating the knob-operated operation plate 49 to minimize the amount of protrusion of the stepped pin 47 from the hole 5e.
and the winding operation becomes possible.

The seventh embodiment (FIGS. 14 and 1)
In 5), the ridge 26 is formed in a wedge-shaped cross section,
The concave portion 27a is formed in a shape conforming to the convex ridge 26, and is temporarily fixed by fitting the two. However, if the convex ridge 26 is formed in a rectangular cross-section and the concave portion is formed in a shape conforming to this,
It can be fixed by fitting both. That is, the hub 5 and the spindle 4 are maintained in a connected relationship unless a releasing operation for lifting the lock plate 27 is performed.

As is apparent from the above description, the present invention is, in short, to maintain the idle movement of the load sheave 2 by integrating the spindle 4 and the hub 5 which rotate as the load chain 3 moves. One feature is that the spindle 4 and the hub 5 are fixed or temporarily fixed in the rotational direction to such an extent as to turn.

In the first to ninth embodiments, since the positioning mechanism is a temporary fixing type having a weak holding force, the holding state is automatically changed when an external force such as a torque of the lever 9 is applied to a certain amount or more. And the advantage is that the winding operation can be obtained with one touch, and the operability is excellent.

In each of the above embodiments, by rotating the hub 5, the screwing position of the hub 5 with respect to the spindle 4 is shifted to the position for the idle operation slightly shifted from the position for the winding operation. However, conversely, by rotating the spindle 4 while keeping the hub 5 in the same position, the screwing position of the hub 5 with the spindle 4 is shifted to the position for the idle operation slightly shifted from the position for the winding operation. You may do so. In such a case, for example, a knob or the like may be attached to the tip of the spindle 4 so that the spindle 4 can be rotated by hand. Then, it is sufficient to hold the hub 5 by hand and turn the knob or the like of the spindle 4 by hand.

Further, the positioning mechanism is not limited to the structure shown in each embodiment, and the hub or the spindle is rotated to rotate the hub by a small angle with respect to the spindle by hand. When the screwing position of the hub to the spindle is shifted to a position for idle operation slightly deviated from the position for winding operation, the screwing position may be maintained so as not to return to the original position. Since there are many possible cases, their structures other than those in the above-described embodiment are not shown and described. Moreover, it is sufficient that the positioning mechanism is held so that the screwing position does not return to the original position, and it is not necessary to necessarily move the screwing position from the position either clockwise or counterclockwise unlike the fixed type, As in the first, third, fourth, sixth, seventh, and ninth embodiments, the screwing position may be greater than the position at the time of the idle operation.

Further, it is not always necessary to make both the hub and spindle structures different from the conventional structure. For example, if the hub has the same structure as the conventional one and the pitch of the threaded portion of the spindle is changed so that it gradually becomes larger than normal toward the outside, when the hub is turned by hand, It will be temporarily fixed by being hooked on the deformed part of the part.

[0036]

According to the present invention therefore, lever hoist of the present invention, Russia
When the screwing position of the hub to the spindle is shifted to the position of the idle operation slightly deviated from the position of the winding operation by the positioning mechanism that has received the lock operation, the screwing position is held so as not to return to the original position. Since the relative position between the spindle and the hub is kept in a state where the brake is not applied, a stable idle operation can be obtained without the brake being applied midway. Further, when the positioning mechanism is released by receiving an unlocking operation, there is no member such as a coil spring that constantly pushes the hub outwardly unlike a conventional spring-type lever hoist, so that the hub is not provided with a ratchet gear and a brake lining. Since the contact pressure can be ensured, it is possible to eliminate a crash accident caused by the inoperative brake in the unwinding operation of the lightweight article. In addition, if the holding force of the positioning mechanism is set to a force that is less than the torque applied to the hub during hoisting, the winding operation can be performed immediately.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a main part of a first embodiment,

FIG. 2 is a partial front view showing relative positions of a hub, a spindle, and the like during a winding operation of the first embodiment;

FIG. 3 is a partial front view showing relative positions of a hub, a spindle, and the like at the time of idling operation of the first embodiment;

FIG. 4 is a sectional view taken along line IV-IV of FIG. 2;

FIG. 5 is a sectional view taken along line VV of FIG. 3;

FIG. 6 is a diagram corresponding to FIG. 2 during the winding operation of the second embodiment,

FIG. 7 is a diagram corresponding to FIG. 2 during the winding operation of the third embodiment,

FIG. 8 is a diagram corresponding to FIG. 3 during a free running operation of the third embodiment,

FIG. 9 is a diagram corresponding to FIG. 2 during the winding operation of the fourth embodiment,

FIG. 10 is a diagram corresponding to FIG. 3 during a free running operation of the fourth embodiment,

FIG. 11 is a partial front view showing relative positions of a hub, a spindle, and the like at the time of idling operation of the fifth embodiment, and showing magnets by phantom lines at the time of winding operation;

FIG. 12 is a partial front view showing relative positions of a hub, a spindle, and the like at the time of idling operation of the sixth embodiment, and showing pins in virtual lines at the time of winding operation;

FIG. 13 is an enlarged sectional view of a hub around a pin according to a sixth embodiment;

FIG. 14 is a partial front view showing relative positions of a hub, a spindle, and the like at the time of idling operation of the seventh embodiment, and showing ridges at the time of winding operation by virtual lines;

FIG. 15 is a sectional view of a hub according to a seventh embodiment;

FIG. 16 is a partial front view showing relative positions of a hub, a spindle, and the like according to an eighth embodiment;

FIG. 17 is a sectional view of a hub according to an eighth embodiment;

FIG. 18 is a partial front view showing relative positions of a hub, a spindle, and the like at the time of idling operation of the ninth embodiment, and showing a cam at the time of winding operation by a virtual line;

FIG. 19 is a diagram corresponding to FIG. 2 during the winding operation of the tenth embodiment,

FIG. 20 is a diagram corresponding to FIG. 3 during a free running operation of the tenth embodiment,

FIG. 21 is a partial front view showing relative positions of a hub, a spindle, and the like at the time of idling operation of the eleventh embodiment, and showing pins in virtual lines at the time of winding operation;

FIG. 22 is a sectional view of a hub according to an eleventh embodiment;

FIG. 23 is an enlarged sectional view around a pin in an eleventh embodiment.

[Description of Signs] 1 Main frame 2 Load sheave 3 Load chain 4 Spindle 5 Hub 5c Projection 6 Fixed friction plate 7 Ratchet gear 8 Brake lining 9 Lever 11 Leaf spring

Claims (1)

(57) [Claims] 1. A main frame, a load sheave rotatably mounted on the main frame, a spindle mounted on the main frame so as to rotate in conjunction with the load sheave, and a spindle fixed to the spindle. A fixed friction plate, a hub that is screwed to the spindle and is rotated by a lever that swings around the spindle, a ratchet gear and a brake lining that is loosely fitted to the spindle between the fixed friction plate and the hub. A ratchet claw attached to the main frame so as to mesh with the ratchet gear;
A positioning mechanism for holding the screwed position so that the screwed position does not return to the original position when the screwing position of the hub with the spindle is shifted to a position during the idle operation slightly deviated from the position during the winding operation; When it is received, the positioning mechanism operates and the
When the unlocking operation is received, the positioning mechanism will not operate.
A chain lever hoist characterized in that it is configured as follows.