12 safety protection devices for escalators

When using an escalator, moving parts will come into direct contact with passengers, and improper use may cause personal injury. To ensure the safety of passengers, engineers have installed a variety of safety protection devices on escalators.

What are the safety protection devices for escalators? What is the specific function of the safety protection device?

1. Comb plate safety protection device
The comb plate is pressed and positioned by a compression spring. When the passenger’s foreign objects are embedded in the comb teeth, the comb plate immediately moves forward. When it moves to a certain distance, the forward force of the steps lifts the comb plate and activates the micro switch. action to cut off the control circuit and stop the escalator.
2. Apron board safety protection device
There is a gap between the escalator skirt and the side of the steps. During normal operation, the gap between the skirt and the steps is not greater than 4mm on one side, and the sum of both sides is not greater than 7mm. To ensure the safety of passengers, escalators are generally equipped with a skirt safety switch. When foreign objects get stuck in the gap, the escalator will stop running immediately. In order to prevent passengers’ shoes and other foreign objects from coming into contact with the skirt board of the escalator, anti-contact devices are installed on the skirt boards on both sides. The common ones are brush type and rubber strip type.
3. Drive chain safety protection device
The drive chain breakage protection device has two functions. The first is to send out a chain break signal when the chain breaks, causing the auxiliary brake to act immediately for escalators equipped with auxiliary brakes; the second is to cut off the escalator safety circuit when the chain is excessively loose, causing the escalator working brake to act.
4. Step chain abnormality protection device
The step chain abnormality protection device stops the escalator when the step chain is overextended or broken. This device stops the escalator when the chain that directly drives the steps breaks or is overstretched.
5. Step collapse safety protection device
The step collapse safety protection device is installed on the guide rail at the upper and lower turns. After any part of the escalator collapses, it will no longer mesh with the comb teeth. The step wheel shaft or step sprocket shaft will quickly deflect the swing bar, driving the micro switch to action, thereby cutting off the control circuit. , causing the escalator to stop running.
6. Step missing protection device
When the escalator steps and pedals are broken or lost, the missing step protection device can detect the problem in time and stop the escalator through its own control system to prevent casualties caused by collision or squeeze.
7. Overspeed detection device
The photoelectric speed detection device installs a photoelectric disk on the high-speed shaft of the drive host reduction box, and detects the actual running speed of the escalator through a photoelectric switch. When the running speed of the escalator exceeds a certain value, the control circuit is automatically cut off.
8. Anti-reversal safety protection device
The structure of the anti-reversal device is mostly mechanical, but some also use an electronic anti-reversal device, which detects the direction of the motor at any time through a photoelectric switch. When an unexpected reversal occurs, the brake is activated and the escalator stops.
9. Handrail synchronous monitoring device
When the handrail works normally, it should be synchronized with the steps. If the handrail speed is too slow, passengers will lose their center of gravity and fall. The standard stipulates that the allowable deviation of the handrail to the step speed is 0~+2%, and does not stipulate that a handrail speed detection device must be installed. Escalators without detection devices need to be manually tested during daily inspection and maintenance to ensure that the handrails are synchronized with the steps. Generally speaking, the handrail synchronous monitoring device will stop the escalator when the maximum deviation between the handrail speed and the actual speed of the steps exceeds 15% and the duration reaches 5S~15s.
10. Safety protection device for handrail breakage
The handrail is a force-bearing component. It is subject to long-term driving force and friction during work, and the handrail may break. Therefore, when the handrail breakage safety protection device breaks the handrail, the rocker arm will lift up and trigger the safety switch, causing the escalator control circuit to disconnect and stop running.
11. Machine cabin cover switch protection device
When the upper and lower cabins of the escalator are opened, the protection switch of the cabin cover switch protection device will act and the escalator will stop running, preventing the elevator from starting the escalator under inspection. Short circuiting or human failure is strictly prohibited in daily management.
12.Emergency stop device
The emergency stop device is generally installed on the apron board at the entrance and exit. It is a red button. When an unexpected emergency is found, press this button immediately. It is used to stop the equipment immediately in an emergency to prevent the occurrence of accidents or prevent accidents. continuation.

The above is an introduction to escalator safety protection devices. The application of safety protection devices can effectively reduce the occurrence of escalator accidents and prevent or mitigate the injuries that accidents may cause to passengers.