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US4392147A Expired / Lapsed US ⏱️ 0.0 years remaining

Apparatus for supplying and regulating a writing medium to the writing unit of a writing or drawing machine

Assignee: JS Staedtler KG
•
Filing: 1981-06-30
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Granted: 1983-07-05
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Expires: 2001-06-30
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Abstract

Abstract An apparatus for supplying a liquid writing medium to the writing unit of a writing or drawing device has a writing unit connected by a flow line to a dip tube in a container for a liquid writing medium. The bottom of the container is located in substantially the same horizontal plane as the writing tip of the writing unit. From a suitable source, air is supplied under pressure to the surface of the writing medium within the container. The surface area of the writing medium within the container is greater than the surface area of the writing medium within the writing unit. A regulating valve connected between the container and source of air under pressure regulates the flow of liquid writing medium by supplying writing medium when the writing unit is operative and interrupting the writing medium when the writing unit is nonoperative.

Inventors

  • 👤 Hans-Dieter Rosel

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 19:16
CPC Classifications
B; B43; B43L; B43L13/00; B43L13/02; B43L13/022; B43L13/024; G; G01; G01D; G01D15/00; G01D15/16

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 187 words
In an apparatus for supplying a liquid writing medium to the writing unit of a writing or drawing device or the like, a closed air-tight container for a liquid writing medium having a bottom, said container having a substantially vertical tube therein dipping below the surface of writing medium therein, a writing unit having an ink chamber therein and a writing tip and connected to said tube in the container by a flow line, the bottom of said container disposed in substantially the same horizontal plane as said writing tip of the writing unit, means connected to said container for supplying air under pressure to the surface of the writing medium within the container, valve means interconnected between said container and said air supplying means for regulating the flow of liquid writing medium to the writing unit by supplying writing medium when the writing unit is operative and interrupting the writing medium when the writing unit is inoperative, the surface area of the writing medium within the container being considerably greater than the surface are of the writing medium in the ink chamber within the writing unit.
Claim 2
Dependent Claim 187 words
In an apparatus for supplying a liquid writing medium to the writing unit of a writing or drawing device or the like, a closed air-tight container for a liquid writing medium having a bottom, said container having a substantially vertical tube therein dipping below the surface of writing medium therein, a writing unit having an ink chamber therein and a writing tip and connected to said tube in the container by a flow line, the bottom of said container disposed in substantially the same horizontal plane as said writing tip of the writing unit, means connected to said container for supplying air under pressure to the surface of the writing medium within the container, valve means interconnected between said container and said air supplying means for regulating the flow of liquid writing medium to the writing unit by supplying writing medium when the writing unit is operative and interrupting the writing medium when the writing unit is inoperative, the surface area of the writing medium within the container being considerably greater than the surface are of the writing medium in the ink chamber within the writing unit.
Claim 3
Dependent Claim 22 words
In an apparatus as claimed in claim 1 wherein said container is stationary and said writing unit is vertically and horizontally displaceable.
Claim 4
Dependent Claim 56 words
In an apparatus as claimed in claim 1 wherein said flow line is flexible and air-tight and has a first end connected to a writing medium chamber in said writing unit and a second end connected to said tube in said container, said tube having an open end closely spaced from the bottom of the container.
Claim 5
Dependent Claim 40 words
In an apparatus as claimed in claim 1 wherein said writing unit is connected to said container by a releasable connection to define a single unit, a quick-release coupling in the flow line between said writing unit and said container.
Claim 6
Dependent Claim 22 words
In an apparatus as claimed in claim 1 wherein said valve means comprises an opening to the atmosphere to vent the apparatus.
Claim 7
Dependent Claim 22 words
In an apparatus as claimed in claim 5 and further comprising a first throttle valve connected in said opening to the atmosphere.
Claim 8
Dependent Claim 40 words
In an apparatus as claimed in claim 1 and further comprising a pressure regulating valve interconnected between said valve means and said air supplying means to regulate air pressure acting on the surface of the writing medium within said container.
Claim 9
Dependent Claim 19 words
In an apparatus as claimed in claim 7 wherein said pressure regulating valve comprises an electromechanically actuated control valve.
Claim 10
Dependent Claim 31 words
In an apparatus as claimed in claim 7 wherein said pressure regulating valve is responsive to the operating speed of the writing unit and to the size of the writing tip.
Claim 11
Dependent Claim 26 words
In an apparatus as claimed in claim 7 and further comprising a second throttle valve interconnected between said air supplying means and said pressure regulating valve.
Claim 12
Dependent Claim 26 words
In an apparatus as claimed in claim 1 wherein the pressure on the surface of the writing medium in the container is 0.05 to 1.0 bar.
Claim 13
Dependent Claim 25 words
In an apparatus as claimed in claim 1 wherein said air supplying means has a discharge line and a check valve in said discharge line.
Claim 14
Dependent Claim 25 words
In an apparatus as claimed in claim 1 wherein said writing tip has a vertical displacement of 1-10 mm. between its operative and nonoperative positions.
Claim 15
Dependent Claim 31 words
In an apparatus as claimed in claim 1 wherein there is a vertical distance of 1-20 mm. between the bottom of said container and the writing tip in its operative position.

References Cited (Backward Citations)

US2606093A Cited
US3543279A Cited
US3906513A Cited
US3719952A Cited
US3835881A Cited
US3943527A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-07-04 1987-01-03 1987-07-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-07-04 1991-01-03 1991-07-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-07-04 1995-01-03 1995-07-05 $7700.00 Window Closed / Lapsed

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