# How the Super Soaker's Pinch-Trigger and Built-In Tank Work > A 1994 patent by Lonnie Johnson for a high-pressure toy water gun featuring a built-in, non-detachable tank pressurized by a hand pump and controlled by a simple pinch-valve trigger. - **Patent:** US 5305919 - **Original title:** Pinch trigger hand pump water gun with non-detachable tank - **Owner:** Individual - **Granted:** 1994 - **Status:** Public domain (expired) - **Times cited:** 27 - **Field:** mechanical, gaming ## What it does This patent describes a high-pressure toy water gun that uses compressed air to shoot a continuous stream of water. A hand pump built into the gun's body forces air into a non-detachable external water tank, pressurizing the air and water inside. A flexible tube runs from the bottom of this tank, through the gun's barrel, to the nozzle. To keep the water from shooting out immediately, a spring-loaded metal bar pinches this tube shut. When you pull the trigger, it lifts the pinch bar off the tube, allowing the highly pressurized water to escape through the narrow nozzle in a powerful, steady stream. ## What it does NOT cover - Does not cover water guns with detachable water tanks that screw off to be refilled. - Does not cover water guns that use motorized or electric pumps to pressurize the water. - Does not cover trigger mechanisms that use traditional sliding piston valves instead of pinching a flexible tube. - Does not cover pressurized water guns where the pressurized chamber is completely separate from the main water reservoir. ## The clever bit Instead of a complex, expensive, and leak-prone mechanical valve, the trigger uses a simple spring-loaded bar to pinch a flexible tube shut. Even cleverer: if the air pressure inside the tank gets dangerously high, the pressure itself forces the pinch bar open slightly, acting as an automatic safety release valve. ## Real-world examples 1. Larami Super Soaker models with fixed, non-removable tanks 2. Classic air-pressurized toy water blasters from the mid-1990s ## Why it matters This patent represents a key evolution of Lonnie Johnson's famous Super Soaker technology. By integrating a non-detachable, high-pressure tank directly onto the gun's frame and using a simple pinch-tube trigger, it made high-power water guns cheaper to manufacture, safer, and less prone to leaking than earlier models with removable bottles. ## Frequently asked questions ### What does How the Super Soaker's Pinch-Trigger and Built-In Tank Work cover? A 1994 patent by Lonnie Johnson for a high-pressure toy water gun featuring a built-in, non-detachable tank pressurized by a hand pump and controlled by a simple pinch-valve trigger. ### Who owns patent US 5305919? Individual owns this patent, granted in 1994. ### When does this patent expire? This patent has expired and is now in the public domain — anyone can use the invention freely. ### What is patent US 5305919 cited by? This patent has been cited by 27 later patents that build on its ideas. ### What problem does this patent solve? This patent represents a key evolution of Lonnie Johnson's famous Super Soaker technology. By integrating a non-detachable, high-pressure tank directly onto the gun's frame and using a simple pinch-tube trigger, it made high-power water guns cheaper to manufacture, safer, and less prone to leaking than earlier models with removable bottles. ### What does this patent NOT cover? Does not cover water guns with detachable water tanks that screw off to be refilled. **Full plain-English explainer:** https://patentbrief.org/patent/us/5305919/super-soaker-water-gun **Original patent:** https://patents.google.com/patent/US5305919 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How the First Modern Water Slide Was Designed](https://patentbrief.org/patent/us/2982547/slip-n-slide-carrier) — A 1960 patent for a water-based amusement structure featuring a sloped surface and a water supply system to create a sliding experience. - [How the Modern LEGO Brick Design Works](https://patentbrief.org/patent/us/3005282/lego-toy-brick) — The 1958 patent that defined the iconic LEGO brick with hollow tubes inside, allowing bricks to lock together firmly. - [How Lewis Waterman's Original Fountain Pen Design Worked](https://patentbrief.org/patent/us/293545/fountain-pen-waterman) — This 1884 patent describes an early fountain pen designed by Lewis E. Waterman, which aimed to solve common ink-flow problems, making writing smoother and cleaner. - [How a Spring-Loaded Pocket Dispenser Works](https://patentbrief.org/patent/us/2620061/pez-dispenser) — A 1949 mechanical design for a pocket-sized container that uses a spring to push items like pills or candies to the top for easy access. - [How the Wiffle Ball Design Works](https://patentbrief.org/patent/us/2776139/wiffle-ball-mullany) — A 1954 patent for a lightweight, perforated plastic ball designed to curve easily when thrown, famously known as the Wiffle ball.