JPH0960461A - Lowering device for evacuation ladder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lowering device for an evacuation ladder having a simple structure, installed at a low cost, having a secure action, and capable of securing safety by controlling the lowering speed of the evacuation ladder with both a constant-torque spiral spring and a centrifugal brake. SOLUTION: An evacuation ladder 1 is stored in a hatch in the folded state, and a pawl is meshed with a ratchet gear 2 1 to hold the storage state. The pawl is released from the ratchet gear 21 at the time of an evacuation, the ladder 1 is extended by the tare weight, and a lowering wire 9 is delivered. A spool 14 arranged with the winding section 20 of the wire 9 is rotated, the winding section 15 of a constant-torque spiral spring 7 is rotated, and the constant-torque spiral spring 7 on a winding shaft 12 is wound up. The winding of the constant-torque spiral spring 7 gives the lowering resistance to the ladder 1, the quick descent by the tare weight of the ladder 1 is suppressed, and the ladder 1 is lowered and extended at a slow speed. The lower end of the ladder 1 is brought into contact with a veranda on the lower stage, and the ladder 1 can be set to the stable and safe evacuation state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for descending an evacuation ladder, which is controlled by a constant torque mainspring and a centrifugal brake so that the evacuation ladder does not descend suddenly.

[0002]

2. Description of the Related Art Generally, an evacuation ladder needs to be lowered in an emergency, but if it is lowered freely, it accelerates and suddenly falls, which is dangerous, and therefore a gas spring is used as a device for reducing the descending speed. There was something I did.

[0003]

However, the gas spring has the problems that the structure is complicated and the cost is high.

An object of the present invention is to solve the above problems and provide an inexpensive evacuation ladder descending apparatus.

[0005]

In order to solve the above-mentioned problems, an evacuation ladder descending apparatus according to the present invention is a pantograph type evacuation ladder descending apparatus arranged inside an evacuation hatch, wherein the evacuation hatch is the evacuation hatch. The side of the winding shaft is provided with a winding shaft wound with a constant torque mainspring and a winding shaft parallel to the winding shaft. The winding shaft for winding the constant torque mainspring and the end of the evacuation ladder are provided on the winding shaft. A spool having a wire winding portion for winding a descending wire fixed to the portion is rotatably supported, and the rotation of the spool is braked by a centrifugal brake according to the rotation speed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 indicates an evacuation ladder, which is constructed to be expandable and contractible by using a known pantograph, and an evacuation hatch 3 of a veranda 2 in a high-rise building.
The upper and lower lids are folded inside the evacuation hatch 3 as shown by the chain line in FIG. Place 5 and 6 closed, and open and close the upper and lower lids 5 and 6 to evacuate the ladder 1 during evacuation.
As shown by the solid line, the evacuation hatch 3 is pulled out and the lower end is brought into contact with the lower veranda 6.

2 to 4, reference numeral A indicates a descending device for the evacuation ladder 1 attached to one side of the hatch 3 in correspondence with the evacuation ladder 1 as shown in FIG. It is composed of a centrifugal brake 8 and a descending wire 9 of the evacuation ladder 1. The constant torque mainspring 7 is wound around a winding shaft 12 fixed to a frame 11 by a spindle 10 as shown in FIG. 3, and the outer end side thereof is fixed to the frame 11 in parallel with the winding shaft 12. The spool 14 is rotatably fitted to the take-up shaft 13 and wound around the constant torque mainspring take-up portion 15 opposite to the take-up shaft 12 so that the ladder 1 is resistant to the descent. I am doing it.

The centrifugal brake 8 is provided radially inside the spool 14, and a hard ball 1 having a large weight is attached to a sliding groove 17 on the back surface of which a slope 16 is formed which becomes shallower toward the outer peripheral side as shown in FIG.
In this case, the hard spheres 18 are accommodated, and when the hard spheres 18 act on the centrifugal force, the hard spheres 18 move to the outer peripheral side in the sliding groove 17 and are brought into pressure contact with the braking plate 19 by the inclined surface 16 to perform a braking action. Is.

The descending wire 9 of the evacuation ladder 1 is wound around the wire winding portion 20 provided on the spool 14,
The tip end is fixed to the lower end of the evacuation ladder 1 as shown in FIG. 1, and when the ladder 1 descends, the descending wire 9 is pulled out from the winding portion 20 to rotate the spool 14 and the constant torque generated by the winding portion 15. It is configured to perform winding of the mainspring 7 and a braking action of moving the hard ball 18 to the outer peripheral side during abnormal acceleration.

2 to 4, reference numeral 21 indicates a ratchet gear provided on the spool 14 adjacent to the winding portion 20 of the descending wire 9. The ratchet gear 21 is attached to the shaft 22 relative to the frame 11. When the pawl 24 with the handle 23 attached to the shaft is engaged by the spring 25, the rotation of the spool 14 is stopped and the descending wire 7 is not fed out, so that the evacuation ladder 1 does not descend.
However, when the pawl 24 is removed from the ratchet gear 21, the spool 14 becomes rotatable and the descending wire 9 is paid out, so that the ladder 1 comes down.

FIG. 5 shows another embodiment of the centrifugal brake 8. In the centrifugal brake 8 of this embodiment, the winding portion 15 of the constant torque mainspring 7 is used as a brake drum 26, and one end is braked to the inside thereof. A brake shoe 28 having a shaft 27 attached to the drum 26 is provided, and the brake shoe 2
8 is normally separated from the brake drum 26 by a spring 29, and when a centrifugal force larger than the force of the spring 29 acts, the brake shoe 28 is pressed against the brake drum 26 to perform a braking action.

Next, the operation of the evacuation ladder descending device having the above construction will be described. First, the evacuation ladder 1 is stored in the hatch 3 in a folded state, and the stored state is maintained by engaging the pawl 24 with the ratchet gear 21. However, when the pawl 24 is removed from the ratchet gear 21 during evacuation, the ladder 1 pulls out the descending wire 9 while extending due to its own weight, and therefore the spool 14 provided with the winding portion 20 of the wire 9 is rotated, whereby the constant torque mainspring 7 is rotated. The winding portion 15 also rotates and winds the constant torque mainspring 7 on the winding shaft 12, but the winding of the constant torque mainspring 7 gives a drop resistance to the ladder 1, so that a rapid drop due to the weight of the ladder 1 is suppressed. Then, it descends and extends at a slow speed, and its lower end is brought into contact with the lower veranda 2 to be stable and ready for safe evacuation.

However, it is expected that the descent speed of the ladder 1 will be excessively high even if the constant torque mainspring 7 performs the braking and decelerating action during the descent of the ladder. The centrifugal force acts on the sliding groove 1
The ladder 1 is moved to the outer peripheral side and pressed against the braking plate 19 by the slope 16, so that the ladder 1 descends at a safe speed by the double braking mechanism.

When the evacuation ladder 1 is no longer needed,
When the lower end of the ladder 1 is pushed up, the descending wire 9 sags. Therefore, the portion of the constant torque mainspring 7 wound around the winding portion 15 is rewound onto the winding shaft 7 by the restoring force of the constant torque mainspring 7 and spool 14 Since the winding portion 20 of the descending wire 9 is also rotated to wind up the wire 9, the ladder 1 is folded and stored in the hatch 3 as shown by the chain line in FIG. 1. The folding and storing can be performed with a small force.

[0015]

The evacuation ladder descending apparatus according to the present invention controls the descending speed of the ladder by using a constant torque mainspring and a centrifugal brake together, and has a simpler structure than that using a conventional gas spring. Therefore, it can be installed cheaply,
Moreover, since the constant torque mainspring and centrifugal brake are used together, the operation is reliable and the safety is excellent. Further, since the constant torque mainspring applies a pulling force to the lowered ladder, the ladder can be easily stored.

[Brief description of drawings]

FIG. 1 is a side view showing a use state of an evacuation ladder descending apparatus according to the present invention.

FIG. 2 is a cross-sectional plan view showing an embodiment of the evacuation ladder descending apparatus according to the present invention.

3 is a vertical cross-sectional side view taken along line XX of FIG.

FIG. 4 is a vertical sectional side view taken along the line YY of FIG.

FIG. 5 is a side view showing a modification of the centrifugal brake according to the above embodiment.

[Explanation of symbols]

 1 Evacuation Ladder 3 Hatch 7 Constant Torque Mainspring 12 Mainspring Winding Shaft 15 Mainspring Winding Part 9 Falling Wire 20 Wire Winding Part 14 Spool 8 Centrifugal Brake

Claims (1)

[Claims] 1. A descending device for a pantograph-type evacuation ladder disposed inside an evacuation hatch, wherein a side of the evacuation hatch has a winding shaft wound with a constant torque mainspring and a winding shaft parallel to the winding shaft. A shaft is provided, and the winding shaft rotatably supports a spool having a mainspring winding portion for winding the constant torque mainspring and a wire winding portion for winding a descending wire fixed to an end of the evacuation ladder. At the same time, the evacuation ladder descending device is characterized in that the rotation of the spool is braked by a centrifugal brake according to the rotation speed.