US 1447730 A
Description (OCR text may contain errors)
Mar. 6, 1923. 1,447,730 c. R. Pos1 ELECTRIC WRITING INSTRUMENT Filed Nov. 24, 1920 l l S BY W ATTORNEY 5@ Patented Mar. 6, 1923.
UNITED STATES PATENT OFFICE.
CHARLES R. POST, OF NEW ROCHELLE, NEW YORK.
ELECTRIC WRITING INSTRUMENT.
To all wiz-0m z't may concern:
Be it known that I, CHARLES R. Posr, a citizen of the United States, and resident of New Rochelle, in the State of New York, have invented cert-ain new and useful Improvements in Electric lVriting Instruments, of which the following is a specification.
An object of my invention is to provide a writing instrument having a stylus or writing point to be heated sufficiently to scorch or burn paper or analogous material to be written upon to prevent changing or altering such writing. My invention isparticularly adapted for writing upon checks and documents to prevent alteration of the writing without detection of the change.
Another object of my invention is to protect the stylus when not in use to avoid danger from the heated stylus.
My invention comprises novel details of improvement that will be more fully hereinafter set forth, and then pointed out in the claims.
Reference is to be had to the accompanying drawings, forming part hereof. where- 1n- Figure 1 is a side view of a writing instrument embod ing my invent-ion on an enlarged scale; Iyig. 2 is a section on line 2, 2 in Fig. 1; Fig. 3 is an enlarged detail section; Fig. 4 is a cross section on line 4 4 in Fig. 3; Fig. 5 is a fragmentary detail section; Fig. 6 is a detail of a conductor; Fig. 7 is a diagrammatic view illustrating an electric circuit for the instrument.
Similar numerals of reference indicate corresponding parts in the several views.
The barrel or handle member of the instrument is indicated at l, which may be of tubular form of insulating material; such as rubber or fibre. At the writing end the barrel is provided with a tubular tip 2 of non-heat conducting insulating material, such as asbestos. A metal heat conductor core or rod 3, preferably of copper, is located Within bore 2 of tip 2 and has a tapering or pencil-like writing end 3a, in the nature of a stylus, projecting from tip 2. A stop 4 on core 3 near its Writing end bears against the outer end of tip 2 and a stop 5 on core Y3 within bore 2 bears against shoulder 2" at the end of bore 2 of tip 2, whereby core 3 is retained on the tip. The stops 4,
5 are shown in the form of split rings received in recesses 6, 7 respectively of core or rod 3, whereby the latter is detachably retained on the tip, moved and replaced. The arrangement described permits core 3 to be removed from tip 2 and replaced by merely removing and replacing stop 4. Core 3 is to be heated to scorch or burn the paper or material to be writ-ten upon. I have shown a conductor 8 coiled around core 3 within tip 2 and extending from insulated line wires 9 of a cable 10 in the barrel. The conductor 8 is a resistance wire capable of producing required heat around core 3 to roperly heat the latter. The resistance con uctor 8 at its ends may be twisted to the line wires 9 and covered by a winding 11 of asbestos cord to insulate the conductor. I have shown a layer of mica 12 around core 3, a winding of insulated conductor 8 around said mica, a layer 13 of mica over said winding and a winding ol' insulated conductor 8 over mica. 13. The inner winding of conductor 8 is wound from the inner end of core 3 to the outer part and the outer winding of conductor 8 is wound over said inner winding continuing from the outer to the inner part of core 3. The covering 11 and the mica 12, 13 thoroughly protect the resistance conductor 8 from the short-circuiting bet-Ween the windings of the latter. By using conductor 8 of very small gauge wire the 1nstrument may receive current from the ordinary electric service lines in buildings, Without requiring a current regulator or resistance in the circuit to reduce the current. Vhen a conductor 8 of larger gauge is used any suitable regulator or resistance may be in the line to reduce the current flowing to conductor 8, such as shown in Fig. 7 where the cable 1() and resistance lamp 14 are in series in the fixture attached to the service line 15. Instead of lamp 14 a suitable resistance coil may be included in the circuit of cable 10 to reduce current in winding 8. The resistance referred to enables the same to be located at a. suitable distance from the writing instrument so that the heat of the resistance will not interfere with the user of the instrument. The bore 2a of tip 2 is charged with insulating material 16 embedding conductors 9, preferably of asbestos, thereby serving to force the heat since stop 4 may be refrom the windings of conductor 8 forwardly toward the stylus. Any suitable switch may be employed to control the flow of current through the wiring of the instrument.
To protect the stylus when not in use I have provided a sleeve 0r tube 17 slidably mounted upon barrel 1, open at the outer end, adapted to extend over and protect stylus 3a (Figs. 1 and 2) and to be slid along the barrel to expose the stylus, Fig. 3. A spring 18 coiled around barrel l within protector 17 serves to automatically project the protecting sleeve 17 forwardly when t-he sleeve is released. Said spring bears at one end against a stop 19 on the barrel and at the other end against a stop 2O projecting inwardly from sleeves 17 which stop may be punched from the sleeve. The stop 19 may be a split ring received in anl annular recess or groove 21 in barrel 1. The protector 17 has one or more inwardly project-l ing lugs 22 to engage stop 19 to limit the movement of the protector along the barrel, so that the protector, will enclose the stylus when not in use. The barrel 1 is shown provided with an exterior annular recess or groove 23 near tip 2 to receive the inwardly extending rib 24 near the outer end of sleeve 17. Said sleeve is slit or divided longitudinally at 25 so that the adjacent portions may be squeezed or pressed inwardly to engage rib 24 in recess 23, to retain the sleeve in retracted position. The sleeve 23 is shown provided with perforations 26 to permit circulation of air and escape of heat.
When the instrument is to be used the sleeve 17 is retracted from over the stylus or writing point 3a to expose the latter and may be retained by pressing the rib 24 into groove 23 by the fingers of the user, and the current is caused to flow through the windings 8. The core 3 will be heated and the stylusy 3a will receive .sufficient heat to scorch or burn the paper or other material to be written upon, the instrument being used in the nature of a writing pencil. When sleeve 17 is released the spring will project the sleeve forwardly to protect the stylus, so that if the instrument is laid upon a desk or papers while the stylus is hot injury will not result. The lateral flange 27 at the outer end of sleeve 17 may rest upon the desk or papers to raise the sleeve there- 'from to protect the same from heat and permit circulation of air around the sleeve for cooling it.
My invention is particularly useful for writing names and amounts upon bank checks, notes and other instruments, since the heated stylus will scorch or burn the writing in the paper and so change its character where written upon as to prevent alteration of the writing without leaving evidences of the change, whereby to render useless the raising of checks and the like.
The barrel 1 may have one or more holes 1a for ventilation.
Having now described my inventioi1.\\'liat I claim is:
1. A writing instrument comprising a barrel provided at one end with a non-heat conducting tip, said tip having a bore conimunicating at its inner end with the barrel, a heating core within said bore having a stylus extending from the tip, a resistance conductor coiled around the core within said bore, and conductors connected to said resistance conductor and extending through said barrel from its outer end.
2., A writing instrument having a: tip provided with a bore having an open inner end and a closed outer end, a core in said bore, a stylus extending from the core `through the closed end of the tip, a resistance conductor coiled around the core wit-hin said bore, and means communicating with said conductor through the inner end of said bore to connect said conductor with a source of electric current.
3. A. writing instrument having a tip provided with a bore, a core in said bore, a stylus extending from the core throughthe tip, a resistance conductor coiled around the core within said bore, and means to connect said conductor with a source of electric eurrent, and a protector adapted to enclose and expose said stylus.
4. An electric writing instrument com prising a barrel provided with a stylus. means to heat the stylus, and a protector adapted to enclose and expose the stylus.
5'. An electric writing instrument com pris ing a barrel provided with a stjf'lus, means to heat the stylus, a protector sleeve slidable on the barrel to enclose and expose the stylus, and a spring between the barrel and protector and co-operative therewith to push the protector over the stylus.
6. An electric writing instrument comprising a barrel provided with a stylus, means to heat the stylus, and a protector adapted to enclose and expose the stylus. and means co-operative between the barrel and protector to retain the latter retracted from the stylus.
7. An electric writing instrument comprising a barrel provided with a stylus, means to heat the stylus, and a protector adapted to enclose and expose the stylus, said barrel having a peripheral recess, said protector having an inward rib to engage said recess and having aN longitudinal slit to permit the protector to be pressed inwardly to engage the rib with said recess.
8. An electric writing instrument comprising a barrel provided with a st vlus, means to heat the stylus, and a protector adapted to enclose and expose the stylus. said protector having an inward lug. a stop upon the barrel to engage said lug, and a spring 'lac liti
between the barrel and the protector c0- operative with said stop and the protector to push the latter to conceal the stylus.
9. A writing instrument comprising a barrel having a tip provided with a borehaving a shoulder, a core in said bore having a stop againstsaid shoulder and having a stylus projecting through and from the tip, said stylus having a stop at the outer end of the tip, a resistance conductor upon said core, 10 and line Wires in said barrel connected to said conductor.
Signed at New York city, in the county of New York, and State of New York, this 23rd day of November, A. D. 1920.
CHARLES R. POST.