With the continuous growth of the economy, urban infrastructure of all kinds has become increasingly sophisticated. In the past, we would only encounter amenities such as elevators and escalators in major cities; nowadays, however, we can spot them even in supermarkets located in small towns. Yet, for those of you who frequently ride escalators-do you truly understand how they work? We often hear reports of accidents involving escalators causing injuries; why is it that the popular "clog-style" sandals-so commonly worn during the summer-seem to be the escalator's favorite "prey"? And what specific function do the yellow lines found on escalators actually serve?
The Working Principle Of Escalators
An escalator consists of a series of individual components, including a truss, a drive unit, a guide rail system, a step chain, and various safety devices. All components and safety devices are housed within a sturdy metal framework known as a truss.
Simply put, the primary components of an escalator consist of gears located on both sides and a track belt covering them; the track belt is lined on both edges with a row of rollers to facilitate smoother movement. The gears feature a mechanism similar to a bicycle chain, designed primarily to enable the smaller gears to drive the larger ones. The large gears engage with the interior of the track belt; consequently, when the gears begin to rotate, the track belt is set into a continuous, cyclical motion. Resting atop the track belt are the metal steps upon which we typically stand; these steps feature a series of neatly arranged grooves that serve a dual purpose: to provide slip resistance and to interlock with the comb plates located at the ends of the escalator.
These metal steps are not solid; rather, they are fashioned as small, step-shaped iron shells forming a triangular structure. This design allows the steps to stack together at their rotating ends-transforming from distinct steps of varying height into a smooth, continuous surface-thereby preventing them from jamming during their cyclical motion.
Why Shouldn't You Ride An Escalator While Wearing Crocs?
To answer this question, we must first understand the characteristics of perforated clogs. These shoes feature a wide toe box (approximately 20% wider than that of standard footwear). To ensure comfort, they are constructed from thick plastic and have a high instep. Consequently-even when the wearer is standing in a normal position-the toe of the shoe sits much closer to the serrated gap between two escalator steps than a standard shoe would. Furthermore, due to insufficient friction between the plastic sole and the foot, a person's natural standing posture often causes the shoe to slide forward; coupled with the relatively high friction between the plastic material and the escalator mechanism, the moment the shoe becomes wedged often goes unnoticed-meaning that by the time the wearer senses what has happened, it is already too late to pull their foot free.
Simply put, due to their soft material, perforated clogs tend to adhere easily when rubbing against metal or other surfaces. If the wearer does not lift their foot in time, the shoe can readily latch onto the comb teeth at the front and sides of the escalator steps, resulting in entrapment and being dragged into the gap between the step and the skirt panel.
In reality, the reason escalators are prone to causing injuries is that their design inherently incorporates specific gaps. These gaps primarily exist in three locations: between adjacent steps, between the steps and the skirt panels, and between the steps and the comb plates.
The skirt panels are the vertical stainless steel plates located along the sides of the escalator, adjacent to the steps; the comb plates are the flat plates situated at the entry and exit points of the escalator. According to the *Safety Code for the Manufacture and Installation of Escalators and Moving Walks* (GB16899-2011), the gap between two adjacent steps must not exceed 6 millimeters; the gap between a step and a skirt panel must not exceed 4 millimeters on either side, with the combined total for both sides not exceeding 7 millimeters; and the gap between a step and a comb plate must not exceed 4 millimeters. While these gaps may appear small, if a foreign object actually becomes lodged within them during operation, the gap can very likely expand further. To prevent pinching injuries, relevant regulations mandate that escalators be equipped with specific anti-pinch safety devices-such as yellow warning lines painted along the edges of the steps, and safety brushes installed along the sides of the steps (serving as skirt panel anti-pinch devices). When riding an escalator, it is essential to be mindful not to step on the yellow warning lines and to avoid making contact with the skirt panels.
Are The Brushes On Escalators Meant For Brushing Shoes?
Based on the introduction above, we now know that what we commonly refer to as "brushes" are, in professional terminology, known as "skirt panel anti-pinch devices." This assembly consists of two components: a base and the brushes themselves. The base is required to be sturdy and resistant to breakage, while the brushes must be soft yet possess sufficient resilience to spring back to their original shape after coming into contact with a passenger's clothing.
The primary function of these "brushes" is to serve as a warning signal when a passenger's limbs get too close to the gap between the escalator steps and the side panels. If your foot brushes against them, it signifies that you have entered the "caution zone" and should shift your position toward the center of the escalator. Consequently, their function mirrors that of the yellow warning lines mentioned earlier: to provide a visual alert. So, the next time you encounter these "brushes," remember-don't use them to clean your shoes!
