JPS5840240Y2 - Alarm device for mobile ladder installation - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an alarm device installed on a movable ladder that moves along a rail extending over the ceiling, mainly indoors at a telephone office or the like.

In workplaces where this type of mobile ladder is used to perform work at heights, falls from the ladder continue to occur, resulting in a considerable number of casualties every year.

The causes of fall accidents can be roughly divided into the following three types.

(1) When the ladder user fails to brake (when using the ladder, the user is supposed to move the ladder to the desired position and apply the brakes to climb the ladder) (2) Despite the fact that the ladder user is braking while working , if a third party removes the brake and moves the ladder without looking up to see if the worker is present (3) If the ladder tread is not stepped on In (1), the brake is removed. Although implementation is mandatory, the current situation is that it is difficult to ensure compliance due to confusion or neglect.

In addition, some of the work includes MDF work (Mai
There are also cases where braking is inappropriate, such as nDistributing Frame) (7).

Regarding (2), in the past, when work was in progress, a hole indicating "Work in progress" or "In use" was lowered to the footboard at eye level to alert third parties, but this is no longer used. It is unreliable because it is sometimes lowered or the user often forgets to lower it, and it is not as effective as expected.

Regarding (3), the only thing that can be done is to attach non-slip pads to the treads, and there is no other choice but to carefully climb up and down the stairs.

From the above, it can be seen that most fall accidents can be prevented if ladder users and those attempting to move ladders do not neglect safety checks.

Therefore, in order to eliminate safety check mistakes by ladder users and third parties, the present invention automatically and reliably alerts them visually and audibly, thereby preventing falls during work. The object of the present invention is to provide an alarm device for installing a mobile ladder.

This invention consists of a start mud switch, a stop mud switch placed below it, and a display device.The display device operates when the start mud switch is turned on by stepping pressure, and the stop mud switch is turned on by stepping pressure. This is an alarm device for installing a movable ladder, which is equipped with an alarm lamp and a buzzer to stop the ladder, and the buzzer circuit is also cut by braking the brake lever.

Fig. 1 is a diagram showing the configuration of this device, and Fig. 2 is a diagram showing the installation state of this device on a mobile ladder, where 1 is the vertical rod of the ladder, 2
is a tread, and 3 is a handrail.

Reference numeral 4 denotes a display device having a built-in circuit as shown in FIG. 3, for example, and is fixed on the back side of the footboard 2 at a normal height.

5 is a start mud switch, and 6 is a stop mud switch, both of which are placed on the footboard 2.

Reference numeral 7 designates a brake lever, which, when operated, brakes and fixes the ladder, turns off the brake switch 8, and cuts the buzzer circuit.

The display device 4 includes an IC 9 including an input control flip-flop and a flicker control circuit, an amplifier circuit for driving a buzzer 10, and an amplifier circuit for lighting a lamp 11.

All circuit elements are designed to minimize power consumption; IC9 is a C-MOS, buzzer 10 is a piezoelectric type, and lamp 11 is a light emitting diode.

A plurality of lamps 11 are usually prepared. The portion surrounded by a dotted line in FIG. 3 is built into the display device 4.

The display device 4 normally uses a battery as its driving source. To explain the operation of the present invention, first, when climbing a ladder without braking, an input is given to the display device 4 by stepping on the start mud switch 5, the lamp 11 flashes and the buzzer 10 sounds, and the ladder climbs up. It notifies the user that the brakes are not applied, and also alerts third parties that there is someone at the top of the ladder.
It will notify you visually and audibly that the brakes are not applied.

In this case, when the user gets off the vehicle and steps on the stop mud switch 6, the input to the display device 4 is cut off, the lamp 11 goes out, and the buzzer 10 stops sounding.

Further, if a third party applies the brakes without the user getting off the vehicle, the lamp 11 continues to flash and only the buzzer 10 stops sounding, indicating that work is in progress in the brake state.

Then, when the user gets off the vehicle and steps on the stop mud switch 6, the display device 4 is opened and the lamp 11 stops flashing.

Next, if you brake and climb the ladder, the brake switch 8 is turned off and input to the buzzer 10 is cut off, and when you step on the start mud switch 5, the lamp 11 flashes but the buzzer 10 does not sound and the third indicates to the operator that the ladder is in use in a braked state.

In this case, if a third party inadvertently releases the brake even though there is a person above, the buzzer 10 immediately sounds to notify the third party and the worker of the dangerous situation.

Although the present invention is as described above, it automatically and reliably displays the state of the mobile ladder, that is, whether a person is climbing it or not, and whether the brake is released or not. ,
It has the effect of visually and audibly alerting the ladder user and third parties, thereby preventing falling accidents during work, and having a simple structure that can be easily installed on existing mobile ladders.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the device according to the present invention, FIG. 2 is a perspective view from below showing how it is installed on a moving ladder, and FIG. 3 is a circuit diagram of the display device.

Claims (1)

[Scope of utility model registration request] It consists of a start mud switch, a stop mud switch placed below it, and a display device.The display device operates when the start mud switch is turned on by pedal pressure, and stops when the stop mud switch is turned on by pedal pressure. An alarm device for installation on a mobile ladder, comprising an alarm lamp and a buzzer, the buzzer circuit being cut by braking a brake lever.