Sengbusch Self Closing Inkstand #51

The story behind the Sengbusch Self Closing Inkstand is a classic invention tale. Gustav Sengbusch was hard at work as a bookkeeper in the early 1900’s. After taking hours to complete a single ledger page, his inkstand tipped and ruined the entire page. As a result of this event and his frustration he decided to design an inkstand to prevent such a problem. It was this that led to the creation of the Sengbusch Self-Closing Inkstand Company. The inkstands he designed were created to prevent tipping, allowed one hand access to ink, and prevented evaporation.

Here’s how it works:

1. Floating Seal: Inside the inkwell, there’s a floating seal that covers the opening. When the pen is not in use, the seal stays in place, keeping the ink from drying out or spilling.
2. Pen Activation: When you dip your pen into the inkwell, the nib pushes down the floating seal, allowing access to the ink.
3. Closing Mechanism: Once the pen is removed, the floating seal automatically rises to cover the opening, sealing the ink inside again.

Over the years Sengbusch released several different inkwells and inkstands but one of the earliest and longest manufactured was the No. 51. Because the No. 51 was made for such a long period of time it can be difficult to date one.  One way is to look at the outer top.  If there are patent dates on this, then it will have been manufactured after the latest patent date.  However, sometime around the late 1920’s all patent information seems to no longer have been inscribed on these tops and instead started having only Sengbusch or Sengbusch USA inscribed.  Later models had improved apertures and gasket seals. Another way to date these is by the type of plastic material used in the construction of the self-closing mechanism and cap.  These parts were made of hard rubber until at least 1946 but by 1955 they started being made of hard plastic.

The Sengbusch inkstands were so successful, there was widespread use by many businesses and government offices, including the U.S. Postal Service. Sengbusch made inkwells specifically for school desks – set flush with the top of the desk with no edge to catch papers. “A special set of tools, loaned to the schools, makes installation a simple 5-minute operation. Can be fitted to old desks by making the old hole the required size. Should be specified as part of the equipment on all new desks.”

Sengbusch also made a “Lock-Well” that locked firmly into a desk and could not be removed without the aid of a key. These were suitable for banks, post offices, hotels, schools, and any public buildings.

Two examples of a Sengbusch #51 are shown – an earlier version with the patent dates on the lid, and a later version just marked “Sengbusch U.S.A.”

The Sengbusch Self-Closing Inkstand Co. wasn’t only known for its inkwells.  They also manufactured radios, dip pens, pen nibs, paper sorters, ink stands, a mucilage (glue) applicator and the Ideal Moistener.  These last two items were brought under the Sengbusch umbrella in 1916 when the Ideal Moistener Co. of Findlay, Ohio was acquired by Sengbusch.  The Ideal Moistener was one of Sengbusch’s most successful products.

• 726194 Inkstand
• 726195 Ink Well
• 841345 Ink Well
• RE12264 (uspto.gov)