Elevator button panel manufacturing is one of the few applications where a keypad must survive millions of actuations and a completely untrained user base at the same time. The person pressing a car operating panel is not a trained operator; it is a resident holding shopping bags, a courier tapping the button with a key, or a child in a shopping mall pressing every floor at once. In elevator and escalator systems the front panel is therefore a durability component as much as a user interface. Tuşhan Elektronik manufactures membrane switch keypads, embossed graphic panels, backlit (LED) panels and touch panels for car operating panels, landing stations and indicator panels.
What a membrane switch does in elevator button panel manufacturing
A membrane switch is a single-piece, seamless interface built by laminating a graphic overlay, a spacer layer and printed conductive circuit layers with double-sided adhesives. Its main advantage in elevator work is that the front face contains no moving mechanical parts and no openings: there is no gap around the key where cleaning water, spilled drinks or dust can enter. The panel is bonded to the stainless or powder-coated sheet metal body of the car, and the ZIF tail leaving the circuit layer connects directly to the control board through a 1.0 mm pitch connector.
On landing stations the membrane switch combines the call button and the indicator area on one surface. The floor number window, direction arrows and call key are printed on the same polyester film, so the number of separately aligned parts on site drops, joints between the door frame and the panel are reduced, and installation time is shorter.
What the elevator environment demands from the keypad
Vandalism and mechanical impact
In public buildings the button surface meets key tips, coins, fingernails and even cigarettes. For this reason graphics are printed on the second surface (rear face) of the polyester: the ink is trapped between layers, so numbers and symbols survive even when the surface wears. A hard-coated PET overlay is preferred, and where heavy impact is expected the panel should be bonded to a fully supported rigid surface such as the car's own sheet metal body, so that it cannot flex and load the circuit layer.
Cleaning chemicals and fingerprints
Car operating panels are wiped with alcohol-based cleaners several times a day. Glossy surfaces show fingerprints and gradually lose their finish under this regime. A matte or fine-textured surface reduces wipe marks and reflections, and also breaks the hard specular reflection of the car lighting on the panel.
Temperature, humidity and outdoor escalators
Panels at metro exits, open car parks and semi-open retail areas face condensation, rain splash and direct sunlight. These applications target IP65 from the front face, and IP67 where wash-down is possible; the design temperature range is typically kept between -20 °C and +70 °C. Where panels see sunlight, UV-driven yellowing and ink fading become the deciding factors in overlay material and ink selection.
Electrical noise and electrostatic discharge
The car sits next to a variable-frequency drive system and its travelling cables, while in dry air a user touching the metal car wall carries a static charge. Keeping the tail no longer than necessary, routing the tail exit away from motor cabling and, where required, adding a printed shielding and grounding layer over the circuit are the design measures that reduce false call detection at the control board.
Accessibility: embossing, Braille and tactile feedback
Elevator panels are one of the few interfaces that must also serve visually impaired users. Dome embossing over the key and rail embossing around it let the user locate the key without seeing it, and Braille dots can be formed into the polyester overlay with the same embossing tool. Emboss height and the alignment of the printed symbol must be resolved together at tooling stage; otherwise print and emboss drift by a few tenths of a millimetre and the symbol appears off-centre.
The second element of tactile feedback is the switching element. A stainless steel metal dome gives a crisp click, typically in the 2–5 N range, with a general service life of 1–5 million cycles, and its feedback stays clear through gloves. Where a quieter, softer feel is wanted, an embossed polyester key (poly dome) is used; its typical life is 100,000–500,000 cycles, which remains reasonable on low-traffic landing stations. A mixed approach is also common: metal domes on high-traffic ground floor call buttons, poly domes on secondary function keys inside the car.
Backlit floor indicators and button illumination
The illuminated ring confirming a registered call is the most-watched detail in an elevator. LEDs embedded in the membrane construction typically deliver 50,000–100,000 hours, which matches the mechanical life of the panel. The critical design issue is light uniformity: diffuser layers and mask geometry are calculated together so that no hot spot appears directly above the LED and no dark band appears at the edges.
Floor indicators rely on the dead-front effect. With the backlight off the surface reads as plain and blank; when the LED turns on the digit or arrow appears. This requires translucent ink behind the graphic area and an opaque black masking layer around it to block light bleed. On panels exposed to daylight through lobby glazing, maintaining contrast depends on balancing mask density against the optical transmission of the translucent window.
Technical requirement checklist for elevator keypads
- Mounting surface: stainless or powder-coated sheet metal; adhesive selected by surface texture, 3M 467MP (0.05 mm) for smooth surfaces or 468MP (0.13 mm) for painted or textured metal
- Key count and layout: number of floors, -1/B basement and 0/Z/G ground coding, alarm, door open/close, fireman service area
- Tactile preference: metal dome (1–5 million cycles) or poly dome (100,000–500,000 cycles), target actuation force
- Embossing: dome emboss, rail emboss and Braille dot requirements
- Illumination: call confirmation colour, dead-front floor indicator, daylight contrast expectation
- Interconnect: ZIF tail at 1.0 mm pitch, tail exit direction, length and connector position on the control board
- Protection: IP65 or IP67 from the front face, indoor/outdoor use, condensation risk
- Dimensions and tolerance: outline size, window openings, mounting holes; ±0.2 mm die cutting, ±0.3 mm laser cutting
- Surface finish: matte, fine-textured or gloss; cleaning chemical and UV exposure
- Specification: customer drawing, flammability and material requirements, language and symbol variants
Typical construction and specifications
| Graphic overlay | Hard-coated PET 0.125–0.2 mm; PC 0.175–1.0 mm where embossing and rigidity are required |
| Printing | Second-surface screen printing; UV-stable inks, translucent dead-front windows |
| Switching element | Stainless metal dome 1–5 million cycles / poly dome 100,000–500,000 cycles |
| Illumination | LEDs embedded in the membrane stack, typically 50,000–100,000 hours |
| Total thickness | 0.9–1.4 mm in a typical 6-layer construction |
| Interconnect | ZIF tail, 1.0 mm pitch |
| Adhesive | 3M 467MP (2 mil) for smooth surfaces, 468MP (5 mil) for painted or textured metal |
| Cutting tolerance | Die ±0.2 mm, laser ±0.3 mm |
| Protection | IP65 / IP67 from the front face |
Project-based production, export variants and modernisation
A significant share of elevator component manufacturers work for export markets, and the most visible consequence on the panel side is that the same cabin body ships to different markets with different graphics: the ground floor coded G, Z or 0, alarm and fireman symbols changing, non-Latin alphabets requested. A membrane switch answers this at low cost, because the cutting die, layer stack and tail exit stay fixed while only the printing films change. Dozens of variants can then be managed from one mechanical design.
Modernisation and low-volume work
A significant part of elevator business is retrofit, where the panel outline must match an existing sheet metal body with its existing cut-outs and hole positions. In such work, converting field measurements directly into a cutting die is the right route at volume, while laser cutting keeps low-quantity jobs economical without tooling cost. As project quantities rise, moving to a die improves both edge quality and repeatability.
Samples and quotation
If you have a drawing, an existing panel sample, or simply a floor count and expected service conditions, we can define the key layout, embossing and illumination scenario together and prepare a costing. For samples and quotations, contact Tuşhan Elektronik on +90 212 671 65 18 or at info@tushan.com.tr.