JPH027878B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a locking mechanism for a winding drum that winds wire, etc., and is particularly effective when implemented in a winch of a lifter that lifts and lowers loads with a fork. This invention relates to a locking mechanism for a winding drum.

<Conventional technology> The winch used in conventional lifters is
A handle for manual rotation or the output shaft of a motor with a speed reducer is connected to the shaft of the winding drum, and when lifting the load, the winding drum is rotated to wind the wire, and when lowering the load, the winding drum is rotated. It was designed to rewind the wire by rotating it in the opposite direction.

<Problems to be solved by the invention> In the conventional winch described above, for example,
Even if the fork is stuck on a shelf or the like and cannot be lowered, if an operator who is unaware of this situation turns the handle, the take-up drum will continue to rotate, so if the wire becomes slack and the fork comes off the shelf, etc. The wire will drop sharply as the wire slackens. Therefore, there was a risk that the load on the fork would fall to the floor, damaging the load or injuring the worker.

<Means for Solving the Problems> The present invention has been proposed in view of the above, and in a manual winch, the main shaft is passed through the through hole of the winding drum, and a male screw formed on the main shaft is formed in the through hole. The first brake plate, ratchet wheel,
A second brake plate is loosely fitted, and a fixed wheel having an axially movable pin in the boss and a locking groove formed in the flange extending outward from the boss is fixed to the main shaft. is made to be able to contact the second brake plate, a swinging member is loosely fitted to the boss of the fixed wheel, and a presser ring is loosely fitted to the main shaft protruding from the boss of the fixed wheel so that it can come into contact with the end of the pin. At the same time, a protrusion formed on the outer periphery of the retaining ring is capable of contacting the side surface of the swinging member, and a pressing member having a spring that presses the retaining ring toward the swinging member is fixed to the main shaft, and the ratchet is fixed to the main shaft. A ratchet pawl is brought into contact with the outer periphery of the wheel, a locking pawl is pivoted near the fixed wheel, and a swinging member that rotates while being held between the fixed wheel and the retaining ring rotates the locking pawl. In winches that use a drive source such as a motor, the main shaft is inserted into the through hole of the winding drum, and the male thread formed on the main shaft is inserted into the through hole. A first brake plate, a ratchet wheel, and a second brake plate are loosely fitted to the main shaft protruding from the winding drum, and a pin movable in the axial direction is provided in the boss. A fixed wheel having a flange extending outward from the boss is fixed to the main shaft so that the flange can contact the second brake plate, and a swinging member is loosely fitted into the boss of the fixed wheel,
A retainer ring is loosely fitted onto the main shaft protruding from the boss of the fixed wheel so that it can come into contact with the end of the pin, and a protrusion formed on the outer periphery of the retainer ring can come into contact with the side surface of the swinging member. A pressing member having a spring that presses the retaining ring toward the swinging member is fixed to the main shaft, the pressing member or the main shaft is linked to a drive source, a ratchet pawl is brought into contact with the outer periphery of the ratchet wheel, and the fixed wheel is A stop switch operated by a swinging member that rotates while being held between the presser ring and the presser ring is electrically connected to the circuit of the drive source.

<Function> When the main shaft rotates in the winding direction, a load is applied to the winding drum, so the winding drum slightly moves toward the fixed wheel due to the screw engagement between the male thread of the main shaft and the female thread of the winding drum. move and press the first brake plate. Therefore, the fixed wheel, second brake plate, ratchet wheel, first brake plate, and winding drum are integrated by frictional force, and when the main shaft is rotated, the winding drum rotates and winds up the wire. In this state, the pin is pushed by the second brake plate and moves the retaining ring in a direction away from the fixed wheel against the bias of the spring. Therefore, the swinging member is in a freely rotatable state, and even if the main shaft rotates, the swinging member does not rotate together. Therefore, in the invention set forth in claim 1, the locking pawl does not lock in the locking groove of the fixed wheel, allowing rotation of the winding drum. In the invention described in item 2, the swinging member does not act on the stop switch, allowing the drive source to operate.

When the main shaft is rotated in the opposite direction while the fork can freely descend, that is, the wire is under tension, the winding drum rotates in the opposite direction in accordance with the amount of rotation of the main shaft. The wire is therefore unwound and the fork is lowered accordingly.

If the fork gets caught on a shelf and the wire loses tension, and in this state the main shaft is rotated in the unwinding direction, the threading between the female thread of the winding drum and the male thread of the main shaft becomes loose and the winding drum moves slightly in a direction away from the first brake plate. Therefore, the first and second brake plates and the ratchet wheel become movable in the axial direction, and the pin moves toward the brake plate due to the bias of the spring. When the pin moves, the presser ring moves toward the fixed wheel due to the bias of the spring and presses the swinging member.
Therefore, the swinging member is held between the holding ring and the fixed wheel and rotates together with the main shaft. When the swinging member rotates, in the invention set forth in claim 1, the locking pawl locks in the locking groove of the fixed wheel to prevent rotation of the main shaft. In the invention described in item 2, the swinging member acts on the stop switch to stop the drive source. Therefore, the rotation of the winding drum stops and the wire no longer slackens.

<Examples> Examples of the present invention will be described below based on the drawings.

The lifter 1 shown in FIG. 1 is a manual type, and has a support 4 erected on a frame 3 equipped with wheels 2, and a fork 5 is attached to the support 4 so as to be movable up and down. A winch 6 is fixed to
is hung on the pulley 8 at the top of the pillar 4 to change the direction.
The tip of the wire 7 is fixed to the base end of the fork 5.

As shown in FIG. 2, the winch 6 has a main shaft 11 passed through a through hole 10 of a winding drum 9, and a first brake plate 1 attached to the main shaft 11 protruding from the winding drum 9.
2, ratchet wheel 13, second brake plate 1
4 is loosely fitted, the fixed wheel 15 is fixed to the main shaft 11 located outside the second brake plate 14, the swinging member 17 is loosely fitted to the boss 16 of the fixed wheel 15, and the boss 16 of the fixed wheel 15 is loosely fitted. A spring 19 that loosely fits the presser ring 18 onto the main shaft 11 protruding from the main shaft 11 and presses the presser ring 18 toward the swinging member 17.
A bearing 21 is provided on the side surface of a box in which a pressing member 20 having... is fixed to the main shaft 11 on the outside of the presser ring 18, and the tip of the main shaft 11 protruding from the pressing member 20 and the winding drum 9 is fixed to the support 4. It is rotatably supported by 22. In addition, as shown in FIG. 2, on the box side, a ratchet pawl 23 and a locking pawl 24 are each rotatably attached to the shaft, and the ratchet pawl 23 is brought into contact with the outer periphery of the ratchet wheel 13 described above. A locking pawl 24 faces the outer periphery of the fixed wheel 15 from below.

The winding drum 9 has flanges 25, 25 at both ends of a cylindrical portion in which a through hole 10 is formed in the center portion, and a flat friction surface 26 is formed on the side surface of one of the flanges 25. A female screw 27 is formed at the end of the inside 10.

The main shaft 11 has a thickness that allows it to be inserted into the through hole 10 of the winding drum 9, and has a male threaded portion 28 at the tip.
The male threaded portion 28 is screwed into the female threaded portion 27 of the winding drum 9.

The first brake plate 12 is a disk made of a material with a large coefficient of friction, and has a hole 29 slightly larger than the diameter of the main shaft 11 in its center. In addition,
The second brake plate 14 also has a similar configuration.

The ratchet wheel 13 has serrations 3 on the outer periphery.
0... and a hole 31 through which the main shaft 11 passes through the center part.
Established.

The fixed wheel 15 has a flange portion 32 extending outward from one end of a boss 16 in which a through hole for passing the main shaft 11 is formed, and a plurality of locking step portions 33 are formed on the outer peripheral portion of the flange portion 32. In addition, a recessed portion for housing the flat washer 34 is formed in the outer side surface portion of the flange portion 32, and small through holes are bored in the boss 16 along the axial direction with a phase shift of approximately 120 degrees, and each through hole is A pin 35 is inserted therein so as to be able to move smoothly in the axial direction. The pins 35 have a length such that one end abuts the inner surface of the flat washer 34 and the other end slightly protrudes toward the side surface of the boss 16 when the flange portion 32 and the flat washer 34 are flush with each other.

The swinging member 17 that is loosely fitted into the boss 16 of the fixed wheel 15 has a leg piece 36 extending downward from the upper end portion having an opening through which the boss 16 is inserted. By bending the action part 37
has been formed. Therefore, this swinging member 17
When it is loosely fitted into the boss 16 of the fixed wheel 15, as shown in FIG.
Stop in a hanging state.

The presser ring 18 that presses the swinging member 17 is
The pin 35 described above is located outside the opening through which the main shaft 11 passes.
...is a ring having a receiving surface that the other end comes into contact with,
A protrusion 38 is provided on the outer peripheral portion. This protrusion 38
is a continuous annular shape in the embodiment, but it may have any configuration as long as it can press the side surface of the swinging member 17, for example, it may be configured with a plurality of protrusions.

The pressing member 20 has a fitting hole 39 formed on one side of the cylindrical body into which the end of the main shaft 11 is fitted, and
Small holes are formed on the outside of the fitting hole 39 at a phase shift of approximately 120 degrees, and a spring 19 is fitted into each hole, and a radial through hole 40 passing through the center is provided on the opposite side of the fitting hole 39. is drilled in the through hole 40, and an L
The base end portion of the handle 41 is passed through and fixed with a screw 42.

To assemble each of the above-mentioned members to the main shaft 11,
First, the fixed wheel 15 is inserted into the main shaft 11 with the flange portion 32 facing the male threaded portion 28 side, and fixed in a predetermined position. The end wheel 13 and the first brake plate 12 are loosely fitted in this order, and on the other side, the swinging member 17 is passed through and the boss 16 of the fixed wheel 15 is loosely fitted, and then the retainer ring 18 is swinged around the protrusion 38. The main shaft 1 is loosely fitted in the state facing the member 17 side, and finally the main shaft 1 is inserted into the fitting hole 39 of the pressing member 20.
Fit the ends of 1 and secure with screws. The main shaft 11 with each member assembled in this way is connected to the bearing 21,
22, the base end of the handle 41 is passed through the through hole 40 of the pressing member 20, and is fixed with a screw 42, and one end of the wire 7 is fastened and wound around the winding drum 9.

Handle 4 of winch 6 configured as described above
1 is rotated in the right direction (in the winding direction) with the wire 7 under tension, for example, by placing a load on the fork 5, the main shaft 11 rotates clockwise and the male threaded portion 28 is attached to the winding drum. 9, the winding drum 9 moves slightly toward the fixed wheel 15, and the first brake plate 1
Press 2. Therefore, the fixed wheel 15,
second brake plate 14, ratchet wheel 13,
The first brake plate 12 and the winding drum 9 are integrated by the frictional force of their respective contact surfaces, and the winding drum 9 rotates due to the rotation of the main shaft 11 to wind up the wire 7. Therefore, depending on the amount of rotation of the handle 41, the wire 7
is wound up on the winding drum 9, and the fork 5 is thereby pulled up.

In addition, when the wire 7 is wound up as described above, the second brake plate 14 is attached to the pin 3 via the flat washer 34.
5 against the bias of the springs 19... toward the pressing member 20 (right side in Figure 3), the presser ring 18 moves slightly in the direction away from the fixed wheel 15 (right side in Figure 3). This creates a gap on the side surface of the swinging member 17. Therefore, the swinging member 17
is in a freely rotatable state, and even if the main shaft 11 rotates, the swinging member 17 does not rotate together. When the swinging member 17 does not rotate together with the main shaft 11 and swings hanging down, the locking pawl 24 engages the locking step 3 of the fixed wheel 15.
3, the main shaft 11 is allowed to rotate.

When the fork 5 is hoisted up to a desired height and the handle 41 is released, the fork 5 tends to descend due to its own weight and the weight of the cargo. However, the ratchet pawl 23 engages with the saw teeth 30 of the ratchet wheel 13 and prevents the ratchet wheel 13 from rotating, and the frictional force with the first brake plate 12 prevents the winding unit from being integrated with the ratchet wheel 13. Since the drum 9 is prevented from rotating, the fork 5 is prevented from descending.

On the other hand, when the handle 41 is rotated to the left (downward direction) in this state, the winding drum 9 moves very slightly in the direction away from the fixed wheel 15, so that there is a gap between the winding drum 9 and the first brake plate 12. The frictional force temporarily decreases, and the winding drum 9 rotates in the direction in which the wire 7 is released due to the weight of the fork 5 and the load, that is, in the same direction as the main shaft 11. When the winding drum 9 attempts to rotate more than the rotation amount of the main shaft 11, the winding drum 9 moves slightly toward the fixed wheel 15, increases the frictional force with the first brake plate 12, and becomes integrated with the fixed wheel 15. It turns into
Therefore, the winding drum 9 rotates according to the amount of rotation of the main shaft 11 while following the rotation of the main shaft 11, and does not rotate by more than the amount of rotation of the main shaft 11. That is, when the main shaft 11 is rotated to the left, the winding drum 9 rotates following the rotation of the main shaft 11 while repeating locking and release from the first brake plate 12 while reciprocating finely in the axial direction.
Therefore, the fork 5 descends according to the amount of rotation of the handle 41 operated by the operator.

Also, on the way down the fork 5,
When the handle 41 is rotated in the unwinding direction with the tension applied to the wire 7 gone and the wire 7 hit a shelf or the like and cannot be lowered, the female threaded portion 27 of the winding drum 9 and the main shaft 11 The threaded engagement with the male threaded portion 28 becomes loose, and the winding drum 9 moves slightly in a direction away from the fixed wheel 15. Therefore, the first and second brake plates 12, 14 and the ratchet wheel 13 become movable in the axial direction, and the pins 35 move toward the brake plates due to the bias of the springs 19. When the pins 35 move in this way, the retainer ring 18 moves toward the fixed wheel 15 due to the bias of the springs 19, and as shown in FIG. Press. Therefore, the swinging member 17
The protrusion 38 of the holding ring 18 and the fixed wheel 15
The main shaft 11 rotates together with the main shaft 11. When the swinging member 17 rotates together with the main shaft 11, the action portion 37 of the swinging member 17 comes into contact with the locking pawl 24 and locks the tip of the locking pawl 24 with the locking stepped portion 33 of the fixed wheel 15. Therefore, rotation of the main shaft 11 is prevented, the winding drum 9 is stopped, and the wire 7 is no longer unraveled and does not slacken.

In this way, in the present invention, when the tension of the wire 7 is released, the swinging member 17 rotates integrally with the main shaft 11, locks the locking pawl 24 on the fixed wheel 15, and locks the main shaft 11. wire 7.
loosens for a short time until the swinging member 17 acts on the locking pawl 24, but does not loosen after that. Note that the slack in the wire 7 that occurs at this time is extremely small in terms of the amount of movement of the fork 5, and does not pose any practical problem.

The winch 6' shown in FIG. 5 uses a motor 43 with a speed reducer as a drive source for rotating the main shaft 11', and a pressing member 2 is connected to the output shaft of the speed reducer 44.
0' end and connect the working part 3 of the swinging member 17'.
A stop switch 45 is provided facing 7', and the stop switch 45 is electrically connected to the drive source circuit. In addition, the winding drum 9', the first brake plate 12', the ratchet wheel 13', the second brake plate 14', the swinging member 17', the holding ring 18',
The configurations of the pins 35', etc. are similar to those in the above-described embodiment, but there is no need to form a locking step on the outer circumferential portion of the fixed wheel 15'.

In a lifter equipped with an electric winch 6' having such a configuration, when the lifting operation switch 46 is operated, electricity from a power source 47 such as a storage battery is supplied to the motor 43, and the main shaft 11' is driven by the motor 43. Rotate right. When the main shaft 11' rotates clockwise, a slight movement in the axial direction of the winding drum 9' causes the fixed wheel 15', the second brake plate 14', the ratchet wheel 13',
The first brake plate 12' and the winding drum 9' are brought together by frictional force, and the winding drum 9' winds up the wire 7' and raises the fork.

On the other hand, when the lowering operation switch 48 is operated,
The motor 43 reverses and rotates the main shaft 11' to the left.
When the main shaft 11' rotates to the left, the winding drum 9' rotates following the main shaft 11' by the same action as in the previous embodiment, so that the wire 7' is released and the fork descends.

Furthermore, when the fork hits a shelf or the like while operating the lowering switch 48 and the tension applied to the wire 7' is removed, the female threaded portion of the winding drum 9' and the main shaft 1
1' is loosened, and the winding drum 9' moves slightly in a direction away from the fixed wheel 15'. Therefore, the first and second brake plates 1
2', 14' and the ratchet wheel 13' become movable in the axial direction, and the pins 35' move toward the brake plate due to the bias of the springs 19'. When pin 35' moves, presser ring 1
8' moves toward the fixed wheel 15' due to the bias of the springs 19', and the protrusion 3 of the presser ring 18'
8' presses the swinging member 17'. Therefore, the swinging member 17' is held between the protrusion 38' of the holding ring 18' and the side surface of the fixed wheel 15', and rotates together with the main shaft 11'. The swinging member 17' is the main shaft 1
1', the operating part 3 of the swinging member 17'
7' presses the operating part of the stop switch 45. When the stop switch 45 is activated, the power supply to the motor 43 is stopped even if the operator is operating the lowering switch 48. The winding drum 9' therefore stops and the wire 7' no longer slackens.

In this manner, in the electric winch 6' shown in FIG. 5, when the tension in the wire 7' is removed, the swinging member 17' rotates together with the main shaft 11' and acts on the stop switch 45, forcing the motor 43 to move. Stop. Therefore, the wire 7' slackens only for a short time until the swinging member 17' acts on the stop switch 45, but does not slacken thereafter.

Note that the present invention is not limited to the lifter 1 for raising and lowering cargo as in the above-described embodiment, but can also be used for winches for other purposes. Further, the material to be wound around the winding drum 9 is not limited to the wire 7, and may be, for example, a chain.

<Effects of the Invention> As explained above, according to the present invention, when the wire, etc. starts to loosen due to the fork getting caught on a shelf, etc., when the main shaft is rotated in the unwinding direction, the action of the swinging member is reduced. As a result, the locking pawl locks with the locking stepped portion of the fixed wheel, or the swinging member acts on the stop switch to stop the drive source and prevent rotation of the main shaft. Therefore, the wire and the like wound around the winding drum are not rewound any more. As a result, it is possible to avoid troubles such as the fork suddenly descending greatly when the fork comes off the shelf, etc., or the cargo on the fork falling to the floor, ensuring work safety. can.

Further, the present invention similarly operates when the fork descends to the floor and stops. Therefore,
Wires and the like are not unraveled more than necessary, and the wires and the like can be prevented from collapsing or being damaged.

Further, the present invention has a simple structure, reliable operation, and can be attached to an existing lifter.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a side view of a lifter equipped with a manual winch, and FIG. 2 is a side view of a lifter equipped with a manual winch.
The figure is an exploded perspective view of a manual winch, Figure 3 is a sectional view of the winch with tension applied to the wire, and Figure 4 is a state where the tension on the wire is removed and the swinging member is clamped. FIG. 5 is an exploded perspective view of the electric winch. In the figure, 1 is a lifter, 5 is a fork, 6 is a winch, 7 is a wire, 9 is a winding drum, 10 is a through hole, 11 is a main shaft, 12 is a first brake plate, 13 is a ratchet wheel, and 14 is a third 2 brake plates, 1
5 is a fixed wheel, 16 is a boss, 17 is a swinging member, 18 is a presser ring, 19 is a spring, 20
is a pressing member, 23 is a ratchet pawl, 24 is a locking pawl, 27 is a female screw portion, 28 is a male screw portion, 32 is a flange portion, 33 is a locking step portion, 35 is a pin, 38 is a projection, 41 is a 43 is a motor, 44 is a speed reducer, 45 is a stop switch, 46 is a lifting operation switch, 47 is a power source, and 48 is a lowering operation switch.

Claims (1)

[Scope of Claims] 1. A main shaft is passed through a through hole of the winding drum, and a male thread formed on the main shaft is screwed into a female thread formed in the through hole, and a first brake plate is attached to the main shaft protruding from the winding drum. A ratchet wheel, a fixed wheel having a second brake plate loosely fitted therein, having an axially movable pin in the boss and a locking groove formed in the flange extending outward from the boss, is attached to the main shaft. A swinging member is loosely fitted to the boss of the fixed wheel, and a presser ring is loosely fitted to the main shaft protruding from the boss of the fixed wheel, and the end of the pin is fixed so that the flange portion can contact the second brake plate. and a protrusion formed on the outer periphery of the holding ring can come into contact with the side surface of the swinging member, and a pressing member having a spring that presses the holding ring toward the swinging member is fixed to the main shaft. A ratchet pawl is brought into contact with the outer periphery of the ratchet wheel, a locking pawl is pivoted near the fixed wheel, and the swinging member that rotates while being held between the fixed wheel and the retaining ring engages the locking member. A locking mechanism for a winding drum in a winch, characterized in that a pawl is rotated and locked in a locking groove of a fixed wheel. 2 Pass the main shaft through the through hole of the winding drum, screw the male thread formed on the main shaft into the female thread formed in the through hole, and attach the first brake plate, ratchet wheel, and second brake plate to the main shaft protruding from the winding drum. A fixed wheel having a brake plate loosely fitted therein and having an axially movable pin in a boss and a flange extending outward from the boss is fixed to the main shaft so that the flange comes into contact with the second brake plate. A swing member is loosely fitted to the boss of the fixed wheel, and a presser ring is loosely fitted to the main shaft on the outside of the fixed wheel so that it can come into contact with the end of the pin. fixing a pressing member having a spring that allows the formed protrusion to come into contact with the side surface of the swinging member and pressing the presser ring toward the swinging member to the main shaft; linking the pressing member or the main shaft to a drive source; The ratchet pawl is brought into contact with the outer periphery of the ratchet wheel, and a stop switch operated by a swinging member that rotates while being held between the fixed wheel and the retainer ring is electrically connected to the circuit of the drive source. A feature of the winch is the locking mechanism of the winding drum.