# How Margaret Knight's Machine Made Flat-Bottom Paper Bags > This 1871 patent by Margaret Knight describes a machine that automatically folds and glues paper to create flat-bottom bags, a major improvement over earlier V-shaped designs. - **Patent:** US 116842 - **Original title:** Improvement in paper-bag machines - **Owner:** Margaret E. Knight - **Granted:** 1871 - **Status:** Active - **Times cited:** 0 - **Field:** mechanical, manufacturing, consumer_goods, packaging ## What it does Based on the patent title, this invention describes a machine designed to improve the manufacturing of paper bags. Historically, Margaret Knight's work focused on creating machinery that could automatically produce flat-bottom paper bags, a significant advancement over earlier V-shaped bags or those requiring manual finishing. While specific claim details are unavailable for this patent (US 116842), the core mechanism likely involved a system for folding and gluing paper to form a stable, rectangular bottom. This allowed bags to stand upright and hold more contents efficiently. For example, a grocery store could use bags from this machine to pack items, knowing they wouldn't tip over easily. ## What it does NOT cover - Does not cover machines that produce V-shaped or pointed-bottom paper bags. - Does not cover methods for manually constructing paper bags. - Does not cover machines for making bags from materials other than paper, such as plastic or cloth. - Does not cover machines that only print on paper bags without forming them. - Does not cover machines for making bags with handles, as the focus is on the bottom-forming mechanism. ## The clever bit The clever bit was automating the creation of a flat, square bottom for paper bags. Before this, bags often had V-shaped bottoms or required tedious hand-folding to stand upright. Knight's machine made the flat bottom efficiently, making bags far more practical for carrying goods. ## Real-world examples 1. Most modern paper grocery bags 2. Paper bags used in retail stores 3. Lunch bags 4. Takeout food bags ## Why it matters This patent is historically significant as it represents a key invention by Margaret Knight, a pioneering female inventor. Her machine revolutionized the paper bag industry by enabling the mass production of flat-bottom bags. These bags were far more practical and durable than previous designs, making them essential for retail and grocery stores and changing how goods were packaged and carried. ## Frequently asked questions ### What does How Margaret Knight's Machine Made Flat-Bottom Paper Bags cover? This 1871 patent by Margaret Knight describes a machine that automatically folds and glues paper to create flat-bottom bags, a major improvement over earlier V-shaped designs. ### Who owns patent US 116842? Margaret E. Knight owns this patent, granted in 1871. ### When does this patent expire? This patent has expired and is now in the public domain — anyone can use the invention freely. ### What problem does this patent solve? This patent is historically significant as it represents a key invention by Margaret Knight, a pioneering female inventor. Her machine revolutionized the paper bag industry by enabling the mass production of flat-bottom bags. These bags were far more practical and durable than previous designs, making them essential for retail and grocery stores and changing how goods were packaged and carried. ### What does this patent NOT cover? Does not cover machines that produce V-shaped or pointed-bottom paper bags. **Full plain-English explainer:** https://patentbrief.org/patent/us/116842/paper-bag-machine-knight **Original patent:** https://patents.google.com/patent/US116842 --- _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 Modern Disposable Paper Cup Was Invented](https://patentbrief.org/patent/us/1032557/dixie-cup-disposable-paper-cup) — A 1908 patent for a sanitary, single-use paper cup designed to prevent the spread of germs from shared public drinking vessels. - [How the Modern Paper Drinking Straw Was Invented](https://patentbrief.org/patent/us/375962/drinking-straw-stone) — A 19th-century patent for a paper tube coated in wax, designed to replace natural rye grass straws for drinking beverages. - [How Elias Howe Invented the Modern Lockstitch Sewing Machine](https://patentbrief.org/patent/us/4750/sewing-machine-howe) — Elias Howe's 1846 patent for the lockstitch sewing machine, which used two separate threads to create a durable stitch that revolutionized garment manufacturing. - [How Early Industrial Food Mixers Used Planetary Gear Systems](https://patentbrief.org/patent/us/1264128/stand-mixer-kitchenaid-johnston) — A 1918 patent for a heavy-duty industrial mixing machine that used a specific gear arrangement to rotate a beater while simultaneously moving it around the bowl. - [How Levi Strauss Invented the Copper-Riveted Jean Pocket](https://patentbrief.org/patent/us/139121/blue-jeans-riveted-levi-strauss) — This 1873 patent describes the use of metal rivets to reinforce the corners of pockets on work pants, preventing them from ripping under heavy use.