Davis Automatic Inkstand – Pre 1900 Patents

Overview

Developed in Pennsylvania and patented by Emry Davis on March 19, 1889, patent no. 399,844 launched the Davis Inkstand business.

The Davis Automatic Inkstand employs a float-and-dip-funnel system housed within an airtight cover. Pressing your pen into the dip-funnel depresses a hollow float, compressing the trapped air above the ink and forcing ink up into the pen. When you lift the pen, the float rebounds—by buoyancy or an optional spring—drawing the ink back down and exposing only a tiny surface to air.

Construction and Materials

• Glass Reservoir (Well A)
  • Clear pressed glass in the “Chandelier” pattern by the O’Hara Glass Company.
  • Acts as the ink-holding basin and showcases the ink color through its multi-faceted flutes and bead droplets.
• Cover Assembly
  • Inner disk (B) of soft rubber, concave to form a cushion.
  • Outer ornamental metal cover (B*) with a screw-threaded flange (g) that screws onto the glass well, compressing the rubber disk for an airtight seal.
• Dip Assembly
  • Tube (C) of hard rubber (or metal), fitted through the cover’s rubber disk, sealed by a flange (b) and small rubber ring (d), then locked in place by a threaded nut ring (D).
  • Hollow float (F) housed inside tube C.
  • Dip-funnel or dip-tube (G) pressed into float F, its lower end open to the ink in the well, its upper end projecting through an apertured cap (E).

Operational Mechanism

1. At Rest
   • Float F rises to its natural buoyant position, limiting the exposed ink surface to the interior of tube C.
2. Pen Engagement
   • Insert pen into dip-tube G and press downward.
   • Float F moves downward, compressing the air trapped above the ink.
   • Compressed air pressure forces ink upward through G into the pen reservoir.
3. Pen Release
   • Float F rebounds upward—driven by buoyancy and optionally aided by a spring (l’)—and ink recedes back into the well.
   • The narrow dip-tube opening closes behind the float, further minimizing evaporation.

Spring Mechanism

• A light coiled spring (l’) may be installed beneath float F.
• Functions:
  • Provides a quick, snap-action lift to seal the dip-tube rapidly once pen pressure is removed.
  • Keeps the float secured in tube C if the inkstand is overturned, preventing escape.

Anti-Evaporation Features

• Airtight Seal: The rubber disk B compressed by the threaded metal cover prevents air ingress around the well’s rim.
• Minimal Exposure: Only the small internal surface within tube C is ever exposed, dramatically reducing ink evaporation between uses.
• Tube Cap: The small annular cap E fits over the top of tube C when the pen is removed, closing off the remaining opening.

Decorative Base: Chandelier Pattern

The pressed-glass base by O’Hara Glass Company is known as the Chandelier pattern with its vertical fluting and bead-droplet motifs.

Subsequent Patents: Patent No. 413,390 patented on October 22, 1889 made some refinements. The float still rises to seal off the ink in the dip-tube when at rest, but now:

• Ink can’t jet into the funnel (check valve)
• Overflow is captured and returned (chamber G)
• The entire assembly is more airtight (supplemental cover + sealing ring)

Together, these refinements yielded smoother filling, minimal spills, and drastically reduced ink loss between uses.

Patent No. 491,640, granted to Emry Davis on February 14, 1893, introduced a series of refinements to his earlier designs for automatic inkstands—most notably improving ink conservation, cleanliness, and user experience. Here’s a breakdown of the key innovations:

🛠️ Functional Improvements

• Minimized Evaporation: The inkstand was engineered so that ink remained sealed in the well except during actual use, dramatically reducing evaporation.
• Cleaner Ink Supply: A tightly fitted vulcanized rubber cover and air-tight seals helped keep dust and impurities out of the ink reservoir.
• Controlled Ink Flow: A small vertical aperture at the bottom of the ink tube, combined with an air-cushion system, prevented ink from spurting when the pen was pressed into the cup.

🧪 Structural Enhancements

• Buoyant Ink Tube Assembly: The patent introduced a floating ink tube nested inside a buoyant air tube. This assembly could rise and fall with pressure, allowing ink to flow only when needed.
• Inverted Cone Sleeve: The sleeve holding the ink tube tapered downward, guiding the ink tube smoothly and helping concentrate ink displacement.
• Overflow Chamber: An eccentrically placed chamber beneath the cover flange captured excess ink that might otherwise escape between the sleeve and air tube.

✒️ User Experience Features

• Flared Pen Cup with Protective Rim: The pen cup was designed with a flared top and a narrow rim to prevent ink from splashing or creeping up the penholder.
• Adjustable Equilibrium: A removable plug allowed users to regulate the buoyancy and position of the ink tube, making refilling and maintenance easier.

These enhancements made the 1893 Davis Automatic Inkstand more efficient, hygienic, and responsive to the needs of writers, especially in professional or high-volume settings.

Patent No. 626,218, granted on June 6, 1899 to Henry B. Brownell and assigned to Emry Davis, introduced a clever refinement to the Davis Automatic Inkstand’s air regulation system—solving a persistent problem with ink displacement and evaporation. Here’s what changed:

🔧 Key Improvements Over Earlier Designs

• Simplified Air Admission: Earlier models required manually removing a plug and lifting the float to admit air into the chamber—a messy and inconvenient process. This patent added a small projecting tube at the bottom of the float, allowing air to enter the chamber automatically when the float was raised and depressed.
• Cleaner Operation: By eliminating the need to handle plugs or manually manipulate the float, the new design reduced the risk of ink-stained fingers and spillage.
• Consistent Ink Flow: The projecting tube ensured that air could be introduced into the chamber in a controlled way, maintaining proper ink levels and allowing the ink to rise reliably when the pen was pressed into the float.