Sanders Associates Limited

Calcomp Inc.

James Lawrence

Aftab H Kapadya

William C Chow

John M Bertalan

Lloyd N Broome

A media position sensing system for a plotter in which a media is driven along at least one edge thereof comprising a plurality of apertures in the media positioned within the width of the edge and an optical detector positioned along the edge for sensing the appearance of the apertures in order to sense a selected position of the media. In a particular embodiment, the width of the apertures are less than one-half the width of the edge and are offset spaced from one another across the width of the edge to present an effective detection capability equivalent to a single aperture having a width equal to the width of the edge. The apertures extend along the length of the media a distance approximately equal to the width of the edge and are located near the end of the length of the media for sensing the end of the media.

Media position sensing system having a plurality of apertures in the

A support arm for use in a pen plotter having a platen with a platen extension in front of it spaced to provide a slot therebetween to rotatably support a pinch roller above the platen to prevent the edges of plotting media inserted between the platen and the pinch roller from entering the slot. The arm is slidably supported under the platen on one end and passes through the slot to rotatably support a pinch roller above the platen on the opposite end. The arm has a bridging finger extending horizontally in the slot from a point adjacent the opposite end towards the plotting media from a side edge thereof. Preferably, the bridging finger is of a width substantially equal to the width of the slot and has a top surface at the same level as a top surface of the platen.

Pinch roller for pen plotters including platen bridge to prevent media

Pedestal-mounted case for a pen plotter

This invention is a self-adjusting motor mount for holding a driving gear mounted on the shaft of a motor in engagement with a driven gear carried by a back plate disposed in a vertical plane and is particularly useful in a pen plotter. There is a mounting plate carrying the motor and the driving gear. A pivotal mounting carried by the back plate attaches the mounting plate to the back plate at a point above the motor for pivotal movement so as to have the motor pivotally hang from the point. There is a bias spring for resiliently urging the mounting plate to carry the driving gear into engagement with the driven gear. Finally, there is a shock absorber carried by the back plate for absorbing pivotal gear disengaging movement of the mounting plate.

Self-adjusting motor mount for drive motors of a pen plotter

A low-friction, low-play bearing system for use in a carriage coupling drive system for a pen plotter including a moving carriage slidably mounted on a shaft between the ends of and carrying a U-shaped pen-carrying yoke in combination therewith for sliding motion along the shaft and rotary motion about the shaft. A pair of annular ball-bearing thrust bearings are disposed over the shaft between respective ends of the U-shaped yoke and the moving carriage. An annular bias spring such as a wave spring is disposed over the shaft between the moving carriage and one of the thrust bearings to create a longitudinal expansion force resisting play between the moving carriage and the U-shaped yoke.

Carriage coupling device system for pen plotter

An improvement to graphics pen plotters including a pen gripping mechanism for gripping a cylindrical bodied pen in a generally vertical orientation for sensing the presence and type of a pen in the gripping mechanism with a single sensor. There is a multi-channel sensor adapted for producing and sensing a plurality, 'n+1', of parallel light beams disposed one above the other to produce a binary number at an output thereof indicating the ones of the light beams sensed by the sensor. The sensor is disposed to shine the light beams at a position past which the pen is moved by the gripping mechanism. There is also a cylindrical reflective surface disposed about a portion of the body of the pen so as to be struck by the light beams when the pen is being gripped by the gripping mechanism at the position and reflect the light beams back towards the sensor to be sensed thereby. The reflective surfce has 'n' cylindrical strip positions disposed to be struck by 'n' of the light beams for selectively containing non-reflective strips to indicate a binary indication of the pen type whereby one digit of the binary number output indicates the presence or absence of a pen at the position and the remaining 'n' digits of the binary number designate one of 2.sup.n possible pen types. Particular size relationships are disclosed providing preferred error-free operation in a low tolerance environment.

Plotter pen presence and type identification system

A pen type sensor for use in a graphics pen plotter wherein plotter pens are moved along a pre-established path between a pen holding area and a plotting area for reading a plurality of vertically oriented reflective indicia positions thereon to create a binary logic output signal representative of the pen type. There is a hollow body member having a pair of angled front surfaces. Light emitting apparatus is associated with one of the pair of angled front surfaces for directing a light beam to simultaneously strike the indicia positions at a point on the path of pen movement. A plurality of light detectors are associated with the other of the pair of angled front surfaces for receiving on respective sensing surfaces thereof the light beam as it is reflected by reflective indicia on a pen at respective ones of the positions and for creating respective bi-stable output signals reflecting the presence and absense of reflected light on the sensing surfaces. Finally, there is apparatus for reading the output signals from the detector means as the binary logic output signal as pens pass the point on the path.

Pen plotter pen type identification system

Apparatus for accurately raising and lowering the pen and for generating a positional signal for control use in a graphics plotter having a penholding mechanism slidably and rotationally mounted on a beam for longitudinal positional movement along the beam and rotational movement around the beam to affect raising and lowering of a pen held by the penholding mechanism under the control of plotter control logic. There is an actuator rod disposed parallel to the beam for rotational movement about a longitudinal axis. A spring biases the penholding mechanism to the raised position. A ball bearing linkage is provided for smoothly and slidably linking the actuator rod to the penholding mechanism so that as the penholding mechanism is smoothly moved longitudinally along the beam, rotation of the actuator rod will cause corresponding rotation of the penholding mechanism towards the lowered position. Finally, there is powered rotation apparatus connected to the plotter control logic to receive control signals therefrom for accurately rotating the actuator rod in small increments in response to the control signals whereby the penholding mechanism can be rotated to raise and lower a pen held therein accurately in small increments. To provide the feedback signal, there is a transducer operably connected to sense rotation of the actuator rod and develop a signal at an output thereof related to the rotational position of the actuator rod.

Plotter pen up/down control system

In a multi-position graphics plotter pen carousel system employing a pen capping mechanism therein at each pen position for capping and uncapping pens held by the carousel, an improvement for allowing the sensing of pen presence at the pen positions and the indexing of the carousel with a single sensor. Each pen capping mechanism is adapted to assume a first position with a pen in the pen position and assume a second position with no pen in the pen position. A plurality of first sensible attributes are associated with respective ones of the pen capping mechanisms for exhibiting a first characteristic when a pen is contained at the associated pen position and for exhibiting a second characteristic when no pen is contained at the pen position. A plurality of second sensible attributes are associated with respective ones of the pen positions for constantly exhibiting the first characteristic. There is a single sensor for sensing the first and second characteristics and for developing a sensible signal at an output thereof indicating whether the first or second characteristic is presently being sensed. The plotter logic is adapted to sense the first sensible attributes and step the carousel between respective ones of the first sensible attributes when sensing pen presence with the sensor and to sense the second sensible attributes and for step the carousel between respective ones of the second sensible attributes when indexing the carousel with the sensing attributes whereby the sensible signal at the output of the sensor indicating the first characteristic indicates the presence of a pen at a pen position of the carousel when sensing the first sensible attributes and indicates the passage of a pen position when sensing the second sensible attributes to count pen positions to index the carousel.

Pen carousel, pen sensing and indexing

An easily adjustable and automatically aligning pinch roller assembly for use in a graphics plotter. A movable carriage hangs from a supplemental inverted T-shaped track below the main carriage track of the plotter. The pinch roller is pivotally attached to an arm from the carriage. A leaf spring on the carriage pulls the carriage loosely into positional alignment with the pinch roller aligned with the drum while allowing translational movement easily. A second bias spring urges the pinch roller down and the carriage into gripping engagement with the supplemental track with sufficient force to prevent translational movement thereof. A release bar holds the pinch roller off the drum and releases the gripping force to allow the carriage to be slid for adjustment.

Pinch roller assembly

A releasable pen block guide for releasably holding the pen block carriage of an X-Y plotter against the track during horizontal traverse movement. A first pair of wheel sets disposed in 90.degree. relationship are rigidly attached to one side of the pen block so as to guide the pen block carriage along the track when held in contact with one of the edges of the track. A pair of second, double, bogey-mounted wheel sets similarly aligned are carried by the pen block carriage and adapted for movement between a first position in contact with the other of the edges of the track and a second position out of contact with the other of the edges of the track and spaced from the first wheel sets sufficiently to allow the pen block carriage to be removed from the track. The second wheel sets are mounted to respective ends of a leaf spring extending outwardly from the pen block carriage in opposite directions along the edge of the track and parallel thereto, wherein the second wheel sets are bogey-mounted to the outward ends of the leaf spring for pivotal movement between the first and second positions.

Releasable pen block guide

A pen capping mechanism for use in an X, Y graphics plotter, or the like, having a plurality of pens with writing tips requiring sealing between periods of use. A flat bar of plastic is provided as a slider member with an upper surface adapted to sealably mate with the tips of the pens. The slider member is supported for longitudinal movement on a support track and is moved between positions by an operator connected thereto. The member has a plurality of bores therethrough through which respective ones of the pen tips can pass in order to write. The bores are positioned such that as the member is moved through the various operative positions, respective ones of the bores come into alignment with a pen tip such that only one pen tip at a time is in alignment with one of the bores. For minimum required movement, the bores are all of a diameter d and are offset from one another in equal steps of distance d so that moving the member a step of distance d will seal one pen tip which had been exposed and seal the next adjacent one thereto.

Growing community of inventors

Irvine, CA, United States of America

James Lawrence