US 3,939,482 A · Writing apparatus

Abstract

An apparatus that may be used in an automatic drawing system for recording, for example, with pencil lead or ink. In one embodiment using a pencil lead, a push rod connects to a piston which is slideable in a cylinder which has a retaining tube for the lead extending therefrom. Air pressure may be selectively applied to the piston for urging the rod against the lead which is in turn contacting the medium for recording thereon. Retraction of the lead from contact with the medium is performed by a mechanism that moves the cylinder and retaining tube toward the medium after the air pressure has been removed so that the lead slides into the tube, and thereafter moves the cylinder and tube away from the medium to retract the lead from contact with the medium. Detection means are also provided to detect the expending of the lead and a multi-lead holder is indexed so that a new piece of lead is registered with the push rod.

Claims21

Dependent claims

An apparatus for writing or marking on a medium by means of an expendable piece of recording material said apparatus comprising;

means for retaining and guiding the piece of recording material having one end from which the piece of recording material is expelled,
movable means including means contacting the piece of recording material and means for selectively urging the contacting means,
means for commonly supporting said retaining means and movable means,
said means for selectively urging being operable to urge the contacting means against the recording material and to interrupt the urging force preparatory to retracting the piece,
and means for retracting the piece from contact with the medium comprising bidirectional means connecting to said supporting means and means for selectively operating said bidirectional means to move said supporting means and retaining means toward the medium and relative to the stationary piece to thereby cause the piece to be retracted into the retaining means, and to thereafter move said supporting means and retaining means away from the medium to retract the piece from contact with the medium.

2 more elements

An apparatus for writing or marking on a medium by means of an expendable piece of recording material, said apparatus comprising:

a supply of pressurized fluid which may be maintained at a constant predetermined pressure,
movable means having means contacting the piece of recording material,
means for retaining the piece of recording material having one end from which the piece of recording material is expelled and another end for receiving the contacting means,
support means for the movable means and including means for receiving the fluid,
means selectively operable to couple the pressurized fluid to the support means for urging the contacting means against the material, and to uncouple the pressurized fluid preparatory to retracting the piece from contact with medium,
and means for retracting the piece from contact with the medium comprising bidirectional means connecting to said supporting means and means for selectively operating said bidirectional means to move said supporting means and retaining means toward the medium and relative to the stationary piece to thereby cause the piece to be retracted into the retaining means, and to thereafter move said supporting means and retaining means away from the medium to retract the piece from contact with the medium.

3 more elements

Apparatus for writing or marking on a medium by means of a marking material, said apparatus comprising;

means for retaining in spaced relationship a plurality of individual pieces of said marking material,
means contacting one of said pieces of marking material for urging the piece of marking material against the medium,
means for supporting said contacting means,
means for selectively applying a constant pressure to said contacting means to in turn apply a constant pressure to the marking material,
means for withdrawing the piece from contact with the medium comprising means for selectively moving said supporting means and retaining means toward the medium to retract the piece into the retaining means, and away from said medium to withdraw the marking material from the medium,
means for detecting the expending of the piece being used for writing or marking,
means responsive to said detecting means for retracting said contacting means out of said retaining means,
and means responsive to retraction of said contacting means for moving said retaining means so that said contacting means is in alignment with another piece of marking material.

5 more elements

Dependencies are inferred from the claim text.

Writing apparatus

Life of this patent

Writing apparatus

Life of this patent

Abstract

Claims21