Mist-Cooled Produce Display Rack with Integrated Humidifier

The problem

Unrefrigerated produce displays lose moisture rapidly under bright retail lighting. Leafy greens wilt, fruit skins shrivel, and stores face constant shrinkage from unsellable stock. Standalone room humidifiers do not target individual shelves, and open spray nozzles leave standing water. According to the patent, the goal is a rack structure that delivers fog to each basket position while keeping the assembly neat and easy to maintain.

The solution

1. A left support (1) is built hollow so it doubles as an air plenum.
2. Three fog pipes — a first fog pipe (2) at the upper section, a second fog pipe (3) in the middle, and a third fog pipe (4) at the lower section — attach to one side of the left support. These pipes are vertically distributed along the upright and use movable joints for disassembly and cleaning.
3. The far end of the third fog pipe connects to a right support (5), forming a frame.
4. Three fruit and vegetable basket supports (6) sit equidistantly between the left and right supports, while the three fog pipes provide mist outlets at different heights.
5. A humidification system assembly (7) mounts on the opposite lower side of the left support. It houses a water pump (701), air inlet fans (702), a semiconductor refrigeration sheet (703), a water pipe (704), a fog forming pipe (705), a water level sensor (706), piezoelectric ceramic sheets (707), a temperature sensor (708), six atomization sheet driving plates (709) and a main control plate (7010).
6. Because the left support is hollow and communicates with all three fog pipes, mist generated in the fog forming pipe enters the left support and can exit through the connected fog pipes.

Who it is for

• Supermarket produce managers who need to humidify leafy greens and herbs without installing full refrigerated cases.
• Farmers market vendors and farm stands looking for a self-contained display that humidifies picked-that-morning produce throughout the day.
• Commercial kitchen equipment distributors supplying restaurants and juice bars that display raw ingredients openly before preparation.
• Grocery fixture manufacturers wanting to add an active-humidity option to their existing shelving catalogues.

How it works

The main parts

Operating sequence

1. Fill and chill — Water sits in the water pipe (704). The temperature sensor (708) reports to the main control plate (7010), which activates the semiconductor refrigeration sheet (703) until the water reaches the set point.
2. Atomize — The main control plate powers one or more of the six atomization sheet driving plates (709). Each drives a piezoelectric ceramic sheet (707) to vibrate at roughly 1.7 million cycles per second, turning surface water into fine fog inside the fog forming pipe (705).
3. Distribute — Two air inlet fans (702) push the fog out of the forming pipe and into the hollow left support (1). Because the support communicates with the first, second and third fog pipes, mist exits through the fog pipes at the corresponding levels.
4. Protect — If the water level sensor (706) detects a shortage, it sends a high-level signal to the main control plate. The plate pauses all atomization boards and starts the water pump (701) until the level recovers, then resumes misting.
5. Adjust — Retail staff can select how many driving plates run simultaneously to match the humidity needs of different produce types.

Applications

Supermarket leafy green aisles

Lettuce, spinach and herbs dry out fastest under fluorescent lights. The three-tier layout dedicates one fog pipe per shelf height, humidifying greens. Store staff can run fewer atomizer boards on the bottom shelf where heavier root vegetables sit.

Farmers market pop-up stalls

Vendors arrive early and sell through the afternoon. A self-contained rack with its own pump and cooling element removes the need for external plumbing. The movable joints on the fog pipes let the vendor detach and wipe down the tubes after a dusty outdoor market day.

Restaurant prep-line display

Juice bars and salad stations often showcase raw ingredients in open baskets. The semiconductor-cooled mist humidifies cut fruit surfaces, while the independent driving plates allow the chef to turn off mist entirely over delicate pastries on a shared counter.

Wholesale club bulk bins

Large-format stores stack produce deep, meaning items at the back of a bin receive no ambient humidity. Positioning these racks at the front of bulk pallets directs fog backward over the display face, reducing the frequency of staff having to cull outer layers.

Floral shop secondary display

While designed for produce, the same misting principle applies to cut flowers kept in buckets on shelving. The patent describes a semiconductor refrigeration sheet; any effect on bacterial growth would need testing, and the even distribution across three tiers suits mixed bouquets staged for walk-in customers.

Where it is less suitable

• Fully enclosed refrigerated cases — sealed glass-door coolers already manage humidity mechanically; adding an open ultrasonic rack inside would cause condensation on the glass.
• Dry-goods shelving — grains, nuts and packaged items require low humidity, making a misting rack counterproductive.
• Outdoor unsheltered markets in heavy wind — ultrasonic fog dissipates instantly in strong crosswinds before reaching the baskets.