KR20030034419A - an emergency braking device for hoisting drum of an overhead travelling crane - Google Patents

Abstract

PURPOSE: An emergency brake system for a hoisting drum of an overhead traveling crane is provided to prevent winded materials from suddenly falling down by immediately stopping the rotation of the hoisting drum, even if a brake lining is omitted from a brake shoe constraining the hoisting drum by a braking drum. CONSTITUTION: An emergency brake system for a hoisting drum of an overhead traveling crane is composed of a rotational frequency indicating plate(21) attached on an outer peripheral surface of the hoisting drum to rotate with interlocking with the hoisting drum, a sensor(23) detecting the rotational frequency of the indicating plate, a control unit controlling the working of a driving motor(27) according to the rotational frequency detected by the sensor, the driving motor operating a rotary plate assembly to the signal of the control unit, and the rotary plate assembly stopping the rotation of the hoisting drum by protruding a brake lever(38) out of the outer peripheral surface of the hoisting drum by a rotary plate(33) rotated by the driving motor.

Description

An emergency braking device for hoisting drum of an overhead traveling crane}

The present invention relates to a hoisting drum emergency braking device of an overhead crane, and more specifically, hoisting during the operation of hoisting and transporting an object by a hoist of an overhead traveling crane. It relates to a hoisting drum emergency braking device of an overhead crane which can prevent the safety accidents such as falling of the wounded object by immediately stopping the rotation of the hoisting drum in an emergency such as a sudden failure of the drum braking device.

In general, overhead cranes are the most widely used cranes. They are installed on the ceiling of large factories or warehouses such as steel mills, and are hooked down from trolleys or hoists that move freely to the required position on rails attached to the ceiling. A hook or hoist electromagnet is used to pull up a weighted object, such as a coil, to a target point.

Trolleys with hoisting and traversing devices, particularly crab or winch trolleys, are among the trolleys of overhead cranes that move the pickled goods to any position while moving around the rails installed on the ceiling. In this crab (103), a hoisting drum (109) for winding the wire rope (107) on which the wound object (105) is suspended is installed inside the crab (103). The drum 109 is braked by the braking device 111 as shown in FIG. 2 during operation. That is, the braking drum 113 of the braking device 111 that rotates in conjunction with the hoisting drum 109 is pressed by the brake shoes 115 on both sides, as shown in FIG. The hoisting drum 109 is braked by rubbing the surface of the brake lining 116 and the braking drum 113.

However, the lining 116 attached to the inner surface of the brake shoe 115 for stopping the braking drum 113 by friction as shown in FIG. The gap should be adjusted or exchanged, but if left unchecked, there is a risk that the gap between the braking drum 113 and the lining 116 is widened and the lining 116 is easily dropped out of position.

As such, the lining 116 has been fixed to the brake shoe 115 by a cover fixing method or a rivet fixing method so as to prevent the brake lining from easily falling off. However, after the lining 116 is replaced, the lining 116 is fixed. The part was loosened, the eccentric difference occurs when the operator's brake adjustment poor, the lining 116 still had the risk of falling off the brake shoe 115.

Accordingly, the brake lining 116 in the brake shoe 115 which restrains the hoisting drum 109 through the braking drum 113 during the lifting and traversing of the heavy object by the overhead crane 101 shown in FIG. 1. When the fall off the binding force on the hoisting drum 109, the weight of the object being hoisted and the hoist electromagnet 117 descends due to its own weight to impact various equipment or workers installed under the large-scale accidents occur There was this.

Accordingly, the present invention has been proposed to solve the problems of the conventional hoisting drum braking device of the overhead crane, and the brake lining is dropped from the brake shoe braking the hoisting drum for winding the wire rope during use of the overhead crane. Even if a sudden accident occurs, the purpose of the braking of the hoisting drum again to prevent the weight of the object being lifted, and also to effectively absorb the shock caused by such emergency braking.

1 is a front view of a general overhead crane in operation.

FIG. 2 is a side view of the hoisting drum braking device shown in FIG. 1. FIG.

Figure 3 is a partially cutaway perspective view of the hoisting drum mounted inside the emergency braking device of the present invention.

Figure 4 is a perspective view of the hoisting drum and the shock absorber in the state that the brake lever is exposed to the outside through the hole.

5 is an exploded perspective view of the emergency braking device shown in FIG.

Fig. 6 is a cross sectional view of the hoisting drum and shock absorber showing the rotating plate assembly in a pre-operation state;

Fig. 7 is a cross sectional view of the hoisting drum and the shock absorber showing the rotor plate assembly in a post-operation state.

* Explanation of Signs of Major Parts of Drawings *

3: crab base 7: wire rope

9: hoisting drum 21: display panel

23: rotation speed detection sensor 25: control unit

27: drive servomotor 28,29: drive and driven gear

31: rotating plate assembly 32: support plate

33: rotating plate 34: limit slot

35: return spring 37: push rod

38: braking lever 41: wrangler

45: positioning pin 71: buffer hook

73: expectation 75: moving plate

77: hanging block

The present invention, in order to achieve the above object, in the hoisting drum braking apparatus of the overhead crane, a rotation speed display plate attached to the outer peripheral surface of the hoisting drum to rotate in conjunction with the hoisting drum, a sensor for detecting the rotation speed of the display panel A control unit for controlling the operation of the driving motor according to the rotational speed detected by the sensor, a driving motor for operating the rotating plate assembly according to the command signal of the control unit, and a rotating plate rotating by the driving motor It provides a hoisting drum emergency braking device for an overhead crane, which consists of a rotating plate assembly which stops the rotation of the hoisting drum by protruding the brake lever out of the outer circumferential surface.

Hereinafter, the hoisting drum emergency braking apparatus according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 to 5, the hoisting drum emergency braking device of the present invention includes a rotary plate assembly 31 installed inside the hoisting drum 9 of the overhead crane and a driving motor for operating the rotary plate assembly 31. 27) and a rotation speed display panel 21, a sensor 23, and a controller 25 provided outside the drum 9.

Here, the rotational speed display plate 21 is attached to the outer circumferential surface of the drum 9 so as to rotate together with the drum 9 to grasp the rotational speed of the hoisting drum 9, as shown in FIGS. 3 and 4. As a strap, as long as it can grasp the rotational speed of the drum 9 according to the type of the sensor 23, it can be manufactured in any form. As shown as the sensor 23, an optical sensor such as a photoelectric tachometer Where used, black and white reflective plates may be used. As such, the optical sensor 23 installed in the crab base 3 of the overhead crane so as to be adjacent to the display panel 21 detects the reflected light reflected by the black and white display panel 21 to adjust the rotation speed of the hoisting drum 9. The reflected light signal sensed for this purpose is transmitted to the controller 25 through the signal processor 24.

As shown in FIG. 5, the control unit 25 installed adjacent to the sensor 23 and the signal processing unit 24 is connected to the driving servo motor 27 and the rotation speed of the hoisting drum 9 transmitted from the signal processing unit 24 is reduced. The drive motor 27 is started when a predetermined value is exceeded, and the drive motor 27 is attached to one side of the rotating plate assembly 31 as shown, and the drive bevel gear 28 mounted on the motor shaft and the drive is driven. The rotary plate center shaft 42 is driven to rotate through a driven bevel gear 29 engaged at right angles to the gear 28 to start the operation of the rotary plate assembly 31.

As described above, the rotor plate assembly 31 operated by the rotational driving force of the driving motor 27 transmitted through the electric gear trains 28 and 29 is an interior of the hoisting drum 9 as shown in FIGS. 4 to 7. It is fixedly installed in the support plate 32, the rotation plate 33, the return spring 35 and the braking lever 38, wherein the pair of support plate 32 is a disk-shaped support bracket as a hoisting drum (9) is installed so as to face the middle point, the drum in a state orthogonal to the central axis of the drum (9) by a bolt (43) penetrated from the outer peripheral surface of the drum (9) to rotate in conjunction with the drum (9) (9) It is fixed on the inner peripheral surface.

Thus, the rotating plate 33 mounted between the pair of circular support plates 32 fixed inside the hoisting drum 9 has a central shaft 42 and a square shaft fixing portion 44 fitted to the central shaft 42. It is intended to rotate in conjunction with each other, at this time, the limiting slot 34 is formed on the center and concentric circles of the rotating plate 33 and the positioning pin fastened on the support plate 32 facing through the slot 34 ( 45, the maximum rotation angle of the rotating plate 33 is set. In addition, the outer circumferential surface of the rotating plate 33 is formed with a plurality of protrusions of the dorsal fin shape of the dorsal fin which gradually increases the rotation radius, each of the push rod 37 is provided with a braking lever adjacent to the outside when the rotating plate 33 is rotated ( 38 is pressed to allow the bent end 47 of the lever 38 to be exposed out of the hoisting drum 9 through the inlet hole 41.

3 and 5 to 7 are attached between the protruding side of the push rod 37 and the plurality of fixing pins 39 connecting both support plates 32 to elastically support the rotating plate 33. The plurality of return springs 35 serve to return the rotating plate 33 rotated by the length of the limit slot 34 to the original position by the rotation driving force of the driving motor 27, and the fixing pin 39. The length is controlled by the adjusting screw 51 inserted through the fixing pin 39 from the guide tube 49 while being protected and guided by the guide tube 49 extending toward the pusher 37 from the rotary plate 33. The initial set value of the spring rebound value to be adjusted.

The plurality of braking levers 38 mounted in close contact with the outer circumferential surface of the push rod 37 between the return springs 35 on the outer circumferential surface of the rotating plate 33 have an end portion 47 as shown in FIGS. 3 and 5 to 7. ) Is bent to a nearly right angle in the form of a "N", and is pivotally mounted in a state in which it is in close contact with the outer circumferential surface of the rod 37 by a pivot shaft 53 fastened by bolts 55 between both support plates 32. When the rotating plate 33 is returned to its original position by the torsion spring 57 attached to the side, it returns to its original position.

In addition, the emergency braking device of the present invention, as shown in Figs. 3, 4, 6 and 7 is caught by the brake lever 38 exposed out of the outer circumferential surface of the hoisting drum (9) A 71 is provided adjacent to the shock absorber 71, in order to alleviate the impact exerted by the brake lever 38 when braking the drum 9, a base 73, a moving plate 75, a locking block. (77), a stopper (78), a damping spring (80) and a damping bracket (71) composed of a damping adjustment bolt (81).

Here, as shown in more detail in FIG. 3, the base 73 and the movable plate 75 of the shock absorbing member 71 are engaged with each other so that the movable plate 75 can be slidably moved forward and backward on the base 73. It is a pair of dovetails, the upper surface of the moving plate 75, as shown in Figure 7 when the brake lever 38 protrudes out of the outer circumferential surface of the hoisting drum (9) by engaging with the lever 38 to push the drum (9) The engaging block 77 for stopping) is attached. In addition, as shown in FIGS. 6 and 7, the stopper 78 protruding from the rear end of the base 73 is in contact with the moving plate 75 retreating along the locking block 77 to prevent further retraction. As shown in FIG. 3, the hoisting drum 9 hung on the engaging block 77 is finally braked by the braking lever 38 protruding into the shed hole 41.

Thus, by attaching the damping spring 80 to the side of the bracket 79 protruding on the opposite side of the stopper 78 of the movable plate 75 and the base 73 caught by the brake lever 38, the movable plate ( The movement speed is gently reduced until the stop 75 is pushed by the stopper 78 to alleviate the impact applied to the locking block 77 by the brake lever 38 when the hoisting drum 9 is braked. At this time, the bracket 79 is coupled through the damping adjustment bolt 81 for pressing the front surface of the moving plate 75 to adjust the initial set value of the tension applied to the damping spring (80).

Referring to the operation of the hoisting drum emergency braking device of the overhead crane according to an embodiment of the present invention configured as described above are as follows.

When the overhead crane is operating normally as shown in FIGS. 3 and 6, the pressing force of the brake shoe 115 surrounding the brake drum 113 as shown in FIG. 2 is properly adjusted as in the conventional hoisting drum. By adjusting, the operation of the hoisting drum 9 is controlled to transfer the wound object 105 shown in FIG. Thus, the hoisting drum emergency braking device of the present invention does not affect the operation of the normal hoisting drum 9 at all.

However, when the hoisting drum braking device 111 shown in FIG. 2 suddenly fails, in particular, the brake lining 116 attached to the brake shoe 115 inside the brake shoe 115 in contact with the braking drum 113 generates a work. In the case where a failure to drop out of the shoe 115 occurs, the wound object 105 and the hoisting electromagnet 117 shown in FIG. 1 fall as if falling due to their own weight, and at this time, FIGS. The hoisting drum 9 shown in 6 and 7 is made to rotate at high speed at about three times the speed of normal rotation due to the wire rope 7.

As described above, when the hoisting drum 9 rotates at high speed, the rotation speed sensor 23 detects the rotation speed of the display panel 21 that rotates at high speed together with the drum 9 and emergency braking through the signal processor 24. Sends a signal to the control unit 25, and thereby the control unit 25 to operate the drive motor (27). When the driving motor 27 is operated, the rotating plate central axis 42 is rotated through the engaged electric gear trains 28 and 29, and then the square shaft fixing unit 44 is formed integrally with the central axis 42. The rotating plate 33 is rotated by.

In this way, when the rotating plate 33 is rotated by an angle limited by the limit slot 34 and the positioning pin 45 as shown in Figure 7 in the state shown in Figure 6 close contact with the outer peripheral surface of the push rod 37 The brake lever 38 is pressurized by the push rod 37 to expose the bent end 47 out of the hole 41 as shown in FIGS. 7 and 4. Subsequently, the brake lever 38 is stopped by the rotation of the drum 9, thereby stopping the rotation of the drum 9 by being caught by the locking block 77 of the buffer hook 71 as shown in FIG. Since the backward speed of the moving plate 75 to which the 77 is attached is gently reduced by the damping spring 80, the impact applied to the locking block 77 by the brake lever 38 is alleviated.

Then, when the emergency braking is released, the operation of the servo motor 27 is stopped, and the braking lever 38 that is being pressed by the push rod 37 while the rotating plate 33 is returned to its original position by the spring 35 is released. The bent end 47 is introduced into the drum 9 while being returned to its original position by the restoring force of the spring 57, whereby the hoisting drum 9 is restored to its normal rotational state again to end the emergency braking.

As described above, according to the hoisting drum emergency braking device of the overhead crane according to the present invention, the hoisting drum may be shortened even if the brake device of the hoisting drum fails due to dropping of the brake lining during heavy lifting work by the overhead crane. Braking can be performed while minimizing the braking impact within the braking time, thereby preventing damage to surrounding equipment or workers due to the impact of the lifting object.

Claims (3)

In the brake of the hoisting drum (9) of the overhead crane, The rotation speed display panel 21 attached to the outer circumferential surface of the drum 9, the sensor 23 for detecting the rotation speed of the display panel 21, and the sensor 23 so as to rotate together with the hoisting drum 9. The control unit 25 for controlling the operation of the drive motor 27 according to the rotation speed detected by the rotation, the drive motor 27 for operating the rotating plate assembly 31 in accordance with the command signal of the control unit 25, and the drive By rotating plate 33 rotated by motor 27, protruding brake lever 38 out of the outer circumferential surface of hoisting drum 9 to rotating plate assembly 31 to stop rotation of hoisting drum 9; Hoisting drum emergency braking system of the overhead crane, characterized in that the configuration. According to claim 1, The rotary plate assembly 31 is interposed between the pair of support plates 32 and the pair of support plates 32 installed to be orthogonal to a central axis in the drum 9 so as to rotate in association with the hoisting drum 9. The rotary motor 33 is rotated by the limit slot 34 by the drive motor 27, and a plurality of dorsal fin-shaped push rods 37 protrude from the outer circumferential surface thereof, the side of the push rod 37 and the support plate ( It is attached between the plurality of fixing pins (39) for connecting the 32 and the spring (35) to elastically support the rotating plate 33, and when the rotating plate 33 is rotated by the push rod 37 Hoi of the overhead crane, characterized in that composed of a plurality of the brake lever 38 is elastically installed on the outer peripheral surface of the rotating plate 33 so as to be exposed to the outside through the hole (41) of the hoisting drum (9) Sting drum emergency braking system. According to claim 1, The movable plate 75 which is slidably engaged with the male dovetail 72 by the base 73 formed on the upper surface of the male dovetail 72 and the female dovetail 74 formed on the lower surface of the male dovetail 72. Stop block 77 is attached to the upper surface of the locking lever 38 is pushed to the brake lever 38, protrudes on one end of the base 73, the moving plate 75 is pushed along the locking block 77 stops A stopper 78 and a bracket protruding on the opposite side of the stopper 78 so as to gently reduce the moving speed of the movable plate 75 until the movable plate 75 is stopped by the stopper 78. 79) and a pair of damping springs 80 attached to the side of the movable plate 75, and through the bracket 79 to pressurize the movable plate 75, the initial of the damping spring (80) It further includes a shock absorber 71 consisting of a damping adjustment bolt 81 adapted to adjust the tension length. Hoisting drum emergency brake system of the bridge cranes, characterized in that.