JPH09142799A - Device for preventing falling in unloading machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a falling preventing device without the occurrence of an erroneous operation caused by momentary slackening of a wire rope at the time of starting the lowering of a truck. SOLUTION: In an unloading machine having a guide rail 12, a truck 20 vertically moved along the guide rail 12 and a wheel 30 attached to the truck 20 via an axle 31 so as to be rotated and rolled by contacting the guide rail 12, a cam 39 rotated independently of the wheel 30 is attached to the axle 31. The cam 39 is rotated from a non-operation position to an operation position and thereby bites the guide rail 12 and generates a braking force. A swinging pawl 37 as a centrifugal engaging member is attached to the wheel 30. When a centrifugal force generated by the rotation of the wheel 30 is large, the swinging pawl 37 is displaced from the non-operation position to the operation position and engaged with a ratchet wheel 38 associated with the cam 39, and by rotating the cam 39 associatively with the wheel 30, the cam 39 is made to bite the guide rail 12. The cam 39 and the swinging pawl 37 are energized to non-operation positions by springs 42 and 44.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fall prevention device for a simple unloading machine such as a roof hoist used at a construction site.

[0002]

2. Description of the Related Art FIG. 5 shows a general structure of a hoisting machine used at a construction site. This tile hoisting machine comprises a ladder-shaped guide rail 1 extending in the vertical direction, a dolly 2 for lifting and lowering along the guide rail 1, a wire rope 3 for lifting and lowering the dolly 2, and one end thereof. An upper pulley 4 that turns the wire rope 3 downward by winding the wire rope 3 that is connected to the carriage 2 and extends upward,
A winch 5 for raising and lowering the carriage 2 by winding up or unwinding the other end side of the wire rope 3 wound around the upper pulley 4 is provided.

The guide rail 1 has a steeply rising portion 1A and a gently sloping portion 1B which is gently inclined along the roof surface.
The wire rope 3 is guided along the bend of the guide rail 1.

As a fall prevention device for a bogie of a hoisting machine of this kind, a system for generating a braking force for preventing the fall of the bogie when the tension of the wire rope 3 falls below a predetermined level is generally adopted. Was there.

[0005]

However, since the conventional fall prevention device is an operation system according to the tension of the wire rope 3, when the slope of the gentle slope portion 1B is very gentle, the slope from the gentle slope portion 1B is reduced. At the start of lowering of the carriage 2, the lowering speed of the carriage 2 may not catch up with the payout speed of the winch 5.
That is, the speed of the trolley 2 may be less than or equal to the feeding speed of the wire rope 3, and as a result, the wire rope 3 may loosen and the tension may drop, causing the fall prevention device to malfunction. Therefore, it is currently rarely used.

In view of the above circumstances, it is an object of the present invention to provide a fall prevention device for a unloading machine that does not cause a malfunction due to the momentary looseness of the wire rope at the start of lowering of the bogie. .

[0007]

The above object according to the present invention is achieved by the following constitutions. A guide rail (12) extending in the up-and-down direction, and a carriage (20) that moves up and down along the guide rail (12),
A unloading machine comprising a wheel (30) rotatably attached to the dolly (20) via an axle (31) and rolling in contact with the guide rail (12). A cam (39) that is rotatably mounted independently of the wheel (30), and that rotates from an inoperative position to an operating position to bite the guide rail (12) to generate a braking force, and the wheel. When the centrifugal force generated by the rotation of the wheel (30) is large, it is attached to (30),
The wheel (30) is displaced from the non-actuated position to the actuated position.
And a centrifugal engagement member (37) for engaging the cam (39) so as to integrally rotate in a direction in which the cam (39) rotates from the non-actuated position to the actuated position. Fall prevention device for unloading machinery.

In the fall prevention device of the above-mentioned unloading machine, the centrifugal engagement member swings when the centrifugal force due to the rotation of the wheel (30) is large, and the claw portion (37a) is moved outward. Of the rocking pawl (37) for displacing the non-operating position of the cam (39) from the non-operating position to the inward operating position of the cam (39).
When the claw portion (37a) of 7) is displaced to the inner working position, the claw portion (37a) is integrated with the claw wheel (38) that engages with the claw portion (37a) and integrally rotates with the wheel (30). Fall prevention device for unloading machinery.

The fall prevention device for a unloading machine as described above, wherein another axle (32) facing the axle (31) with the guide rail (12) interposed therebetween is the carriage (2).
0), and when the cam (39) is rotated from the non-actuated position to the actuated position, the guide rail (12) is sandwiched between the cam (39) and the separate shaft (32), so that a brake is applied. A fall prevention device for a unloading machine, which is characterized by generating force.

The fall prevention device for a unloading machine according to any one of (1) to (3) above, wherein the centrifugal engagement member (37) is provided.
And the cam (39) respectively actuate the biasing means (42, 4).
4) A fall prevention device for a unloading machine, which is urged to a non-operating position by 4).

According to the present invention, the cam for generating the braking force is operated by the centrifugal force of the wheels that rotate in accordance with the descending speed of the bogie, so that the bogie can be reliably moved when necessary regardless of the looseness of the wire rope. You can make an emergency stop. Therefore, the malfunction due to the looseness of the operation of the wire rope does not occur, and the highly reliable fall prevention function can be secured.

In particular, according to the above construction, the cam is displaced to the operating position by engaging the rocking claw, which is rocked by centrifugal force, with the ratchet wheel integrated with the cam. Do not rotate the cam when it is rotating in the opposite direction of the fall, but when rotating in the direction of the drop,
The cam can be reliably rotated. Therefore, it is possible to apply a reliable brake when the dolly falls.

Further, according to the above construction, since the braking force is generated by sandwiching the guide rail between the separate shaft and the cam, the separate shaft is inserted into, for example, the side groove of the channel type guide rail, and the cam is inserted. Can be arranged outside the same side groove, increasing the degree of freedom in layout of the cam and its operating mechanism.

Further, according to the above construction, since the centrifugal engagement member and the cam are constantly biased to the non-actuated position by the biasing means, it is possible to prevent the brake from being accidentally actuated for some reason. It is possible to apply the brake only when necessary.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. Here, the case of a hoisting machine will be described. FIG. 4 is a perspective view of a main part of the tile hoisting machine of the embodiment. This hoisting machine is similar to that shown in FIG. 5, a guide rail 11 extending in the up-down direction, a dolly 20 that moves up and down along the guide rail 11, a wire rope 3 that hoists and hangs down the dolly 20, Not equipped with upper pulley and winch.

The guide rail 11 is formed in a ladder shape by a pair of parallel rail members 12 and a crosspiece 13 connecting them. The left and right rail members 12 are of a channel type composed of upper and lower flanges 12a and 12b and a web 12c, and are arranged with the groove portions 12d facing outward.

The dolly 20 is provided with a loading plate 22 at the lower end of a plate-shaped base 21, and four legs 23 located outside the rail member 12 project on the back side of the base 21. It is set up. An axle 31 is fixed to each leg 23, and each axle 3
1, a wheel 30 rollingly attached to the upper surface of the upper flange 12a of the rail member 12 is rotatably attached. Further, another shaft 32 is fixed to the leg portion 23 in parallel with the axle 31, and the another shaft 32 is provided in the groove portion 12d of the rail member 12.
Has been inserted. Then, the wheel 30, the separate shaft 32, and the leg portion 23 are engaged with the rail member 12, so that the carriage 20 can travel stably along the guide rail 11 without derailing.

In this hoisting machine, a fall prevention device is incorporated in the upper left and right wheels of the four wheels 30.
Of course, it may be incorporated in all the wheels 30, or may be incorporated only in the lower wheel 30.

1 to 3 are detailed views of the fall prevention device. 1 is an exploded perspective view, FIG. 2 is a vertical sectional view, and FIG. 3 is a wheel 3
It is the front view seen from the outer side of 0. As shown in FIGS. 1 and 2, an axle 31 and a separate axle 32 are provided on a leg portion 23 extended from the carriage 20, and a wheel 30 is rotatably attached to the axle 31 via a bearing 35. There is. Also,
A cam 39 is attached to the axle 30 so as to be rotatable independently of the wheels 30.

The cam 39 is arranged between the wheel 30 and the leg portion 23, and is normally urged by the urging member 42 to the inoperative position. Then, the cam 39 bites on the upper flange 12a of the rail member 12 by rotating toward the rail member 12 side toward the upper side (operating position) as indicated by the arrow (d) in FIG. 1 as necessary. In addition, the upper flange 12a is sandwiched between the groove 12d and another shaft 32 to generate a braking force.

As shown in FIG. 3, the cam 39 has a center of curvature N2 of the outer circumference 39b of the cam portion at a position eccentric from the center of rotation N1, and the cam 39 has a lower end (a left end in FIG. 3) closer to the rail member 12. ), The distance from the rotation center N1 to the cam portion outer periphery 39b gradually increases. The minimum distance from the rotation center N1 to the cam portion outer circumference 39b is set to be the same as the diameter of the wheel 30. Further, the outer periphery 39b of the cam portion is provided with a saw-toothed blade 39a for improving the engagement with the rail member 12.

On the other hand, as shown in FIG. 1 and FIG.
A swinging claw 37 that swings by the centrifugal force generated by the rotation of the wheel 30 is attached to the outer surface of the as a centrifugal engaging member. The swing claws 37 are arranged at two positions in the circumferential direction at equal intervals. The rocking claw 37 may be arranged at one place or at three or more places. As shown in FIG. 3, the swing claw 37 is swingably attached to the wheel 30 by a pin 36, and has a claw portion 37a directed in the arrow (B) direction which is the rotation direction of the wheel 30 when dropped. , A weight portion 37b that is displaced outward by centrifugal force. Therefore, when the weight portion 37b is displaced outward by centrifugal force, the claw portion 3 on the opposite side is
7a is displaced from the outer non-actuated position to the inner actuated position as indicated by the arrow (c).

A claw wheel 38 is provided at a position where the claw portion 37a engages when the rocking claw 37 is rocked by centrifugal force. The pawl wheel 38 has a pawl portion 38a on the entire circumference, is integrated with a cam 39 through a common boss portion 40, and is rotatably attached to the outer periphery of the axle shaft 31 by a slide bearing 41. The ratchet wheel 38 and the swing claw 37 are housed in a recess 30 a formed on the side surface of the wheel 30.

The cam 39 is a return spring (biasing means).
42 is urged to the non-actuated position regulated by the stopper 43, and the swing claw 37 is also urged to the non-actuated position regulated by the stopper 45 by the small spring (biasing means) 44.

Next, the operation will be described with reference to FIGS. For example, it is assumed that the wire rope that lifts the truck 20 is broken and the truck 20 drops in the arrow (a) direction at a speed higher than the normal operating speed (see FIG. 4). In that case, the wheel 30 rotates in the arrow (b) direction at a rotation speed higher than normal, the centrifugal force causes the swing claw 37 to swing in the arrow (c) direction, and the claw portion 37 a of the swing claw 37 claws. The vehicle 38 is engaged. As a result, the cam 39 is moved together with the ratchet wheel 38, and the wheel 30 and the arrow (d) are moved.
The cam 39 bites on the upper flange 12a of the rail member 12 to pinch the upper flange 12a with the separate shaft 32 to generate a braking force. As a result, the carriage 20 is suddenly stopped.

As described above, the cam 39 for generating the braking force is actuated by the centrifugal force of the wheels 30 which rotate according to the descending speed of the carriage 20. Therefore, regardless of the looseness of the wire rope 3, the carriage can be reliably carried out when necessary. 20 can be brought to an emergency stop.

In addition, since the cam 39 and the swinging claw 37 are normally held in the non-actuated position by the return spring 42 and the small spring 44, the brake is not inadvertently actuated for some reason and is necessary. The brakes can be applied reliably only when.

Wheels may be separately attached to the separate shaft 32. Further, in the above embodiment, when the cam 39 is operated, the braking force is generated by sandwiching the upper flange 12a of the rail member 12 with the cam 39 and the separate shaft 32. However, in the groove portion 12d of the rail member 12, It is also possible to fit the wheel 30 to the wheel and obtain the braking force by the tension force of the cam 39 at the time of operation.

[0029]

As described above, according to the invention, the centrifugal force of the wheels that rotate according to the descending speed of the bogie causes
Since the cam for generating the braking force is actuated, it is possible to reliably stop the dolly in an emergency when necessary regardless of the looseness of the wire rope. Therefore, the malfunction due to the looseness of the operation of the wire rope does not occur, and the highly reliable fall prevention function can be secured.

In particular, the swinging claw that swings by centrifugal force is
By engaging the ratchet wheel that is integral with the cam, the cam is displaced to the operating position, so the cam does not rotate when the wheel is rotating in the opposite direction to when it is falling, but it rotates in the direction in which it falls. The cam can be surely rotated during the operation. Therefore, it is possible to apply a reliable brake when the dolly falls.

Further, since the braking force is generated by sandwiching the guide rail between the separate shaft and the cam, the separate shaft is inserted into, for example, the side groove of the channel type guide rail,
The cam can be arranged outside the same side groove, which increases the degree of freedom in layout of the cam and its operating mechanism.

Further, since the centrifugal engagement member and the cam are constantly urged to the non-actuated position by the urging means, it is possible to prevent the brake from being inadvertently actuated for some reason, and only when necessary, the brake is surely operated. You can apply the brakes.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of essential parts of an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II of FIG.

FIG. 3 is a view taken in the direction of the arrow III in FIG. 1;

FIG. 4 is a perspective view showing an external appearance of a carriage and its periphery according to an embodiment of the present invention.

FIG. 5 is a perspective view showing a general configuration of a hoisting machine.

[Explanation of symbols]

 12 Guide rail 20 Bogie 30 Wheel 31 Axle 32 Separate shaft 37 Swing claw (centrifugal engaging member) 37a Claw 38 Claw wheel 39 Cam 42 Return spring (biasing means) 44 Small spring (biasing means)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadashi Kakumoto 2418 Kanaborizuka, Kamiyabe-cho, Totsuka-ku, Yokohama-shi, Kanagawa Toyo Koken Co., Ltd. (72) Masahiko Sunagawa, Kanagawa Tsuka 2418 Toyo Koken Co., Ltd.

Claims (4)

[Claims] 1. A guide rail (12) extending vertically.
And a truck (2 that moves up and down along the guide rail (12).
0) and a wheel (30) rotatably attached to the carriage (20) via an axle (31) and rolling in contact with the guide rail (12), wherein the axle ( A cam (39), which is rotatably attached to the wheel (30) independently of the wheel (30) and rotates from an inoperative position to an operating position to bite the guide rail (12) and generate a braking force. Attached to the wheel (30), when the centrifugal force due to the rotation of the wheel (30) is large, the wheel (30) and the cam (39) are displaced from the non-operating position to the operating position.
A fall prevention device for a unloading machine, comprising: a centrifugal engagement member (37) engaged with the cam (39) so as to integrally rotate in a direction in which the cam (39) rotates from an inoperative position to an operating position. 2. The drop prevention device for a unloading machine according to claim 1, wherein the centrifugal engagement member swings when the centrifugal force generated by the rotation of the wheels (30) is large, and the claw portion (37a). ) For displacing) from the outer non-actuated position to the inner actuated position (37)
When the cam (39) is rotatably attached to the axle (31) and the claw (37a) of the swing claw (37) is displaced to the inner working position, the claw ( 37a) is integrated with a ratchet wheel (38) that engages with the wheel (30) and integrally rotates with the wheel (30). 3. The fall prevention device for a unloading machine according to claim 1, wherein the axle (31) and the other axle (32) facing the guide rail (12) are opposite to each other, the trolley (20). When the cam (39) is rotated from the non-actuated position to the actuated position, the guide rail (12) is sandwiched between the cam (39) and the separate shaft (32) to apply a braking force. A fall prevention device for a unloading machine characterized by being generated. 4. The fall prevention device for a unloading machine according to claim 1, wherein the centrifugal engagement member (37) and the cam (39) are urging means (42, 44), respectively. ), A fall prevention device for a unloading machine, wherein the fall prevention device is urged to a non-actuated position.