Abstract: A portable, parallel straightedge drafting board is disclosed which utilizes a unique wire arrangement with control locks attached thereto to achieve a movable straightedge that will always be parallel to itself when moved during use of the drafting board.

Abstract: An adjustable rip fence for a machine tool has a fence which is movable with respect to the cutting tool due to a rack and pinion. The rail assembly supporting the fence include a pair of stationary rails which are secure to the machine tool. A movable rail telescopically engages each stationary rail and the movement of each rail is equalized by a set of cables and pulleys.

Abstract: A measuring machine produces an essentially linear movement in a moving part by transforming rotary movement to linear movement through a transmission element having a high modulus of elasticity in a longitudinal direction, and which is flexible in a transverse direction. The transmission element has two ends which are each fastened to the same mechanical element, and the transmission element is given a pre-stress which is greater than a maximum force encountered during acceleration while the machine is in use.

Abstract: A drafting device includes a pair of magnetic boards securely mounted to upper and lower surfaces of a base frame respectively, a ruler movably engaged on the magnetic board, a pair of cavities defined in each of the four corners of the lower surface of the base frame, and a protrusion being formed between the pair of cavities. A guiding member is securely mounted to each of the four corners of the base frame and includes a locking block having a first wall member and a second wall member mounted on the upper and lower surfaces of the base frame respectively, a slot being defined in the second wall member through which the protrusion is received, a recess defined in an underside of the locking block between the first and second wall members and having a width equal to the distance between a bottom face of the cavity and the upper surface of the base frame. A guiding line loops around each of the guiding members and passes through two ends of the ruler.

Abstract: A parallel rule which includes a gripper body cover and a rule body, with a gripper body base positioned between them. A plurality of float-contact rollers are installed through respective openings in the rule body and gripper body base. The parallel rule is movable across the paper with only the float-contact rollers contacting the paper, thus minimizing any smearing of drawing ink and the leaving of traces upon the drawing paper. The gripper body cover and an associated end body covers are easily attached and removed from the gripper body base, thus allowing for ease of maintenance.

Abstract: A device for obtaining numerical coordinates of a point or a set of points comprises two stretched strips having a common end attached to a stylus which is placed on a point or moved over a set of points. Each of the other ends of each strip is supplied from a strip reserve consisting of pulleys connected to a restoring spring for applying tension to the strips. Variations in length of the strips are measured in discrete values by a mechanism associated with a computer for correcting the effective length of each strip.

Abstract: Perspective drawing apparatus comprises a straightedge assembly having a blade for guiding a tool and at least one flexible member on a tensioned spool, a free end of the flexible member being connected to an anchor device for location at a vanishing point. The assembly is provided with reference points for determining when the blade is aligned with a ray portion of the flexible member intersecting the vanishing point. Preferably at least two of the flexible members are provided for selectively referencing a plurality of vanishing points of the drawing. The apparatus includes an anchor device incorporating an adjustable arm for locating the vanishing point within or without the drawing surface, the arm being selectively located along an edge of the drawing surface by a clamp having a threaded member conveniently located above the drawing surface. The clamp includes a movable spacer member for accommodating variant thickness of the drawing surface.

Abstract: A parallel straightedge which may be attached to any drawing table wherein the straightedge is arranged for adjustment and is provided with a braking arrangement to allow the straightedge to be fixedly held in any given position and/or orientation. The bottom of the straightedge is arranged on a pair of rollers outboard the working area in order not to smudge the drawing contained thereon. A removable plastic insert along the edge of the metal straightedge bar provides a consistent transparent ruling edge for drawing straight lines while providing a nick-free edge as a guide for cutting instruments when the transparent edge is removed.

Abstract: A ruler, especially a parallel ruler having a parallel guidance system comprising a cord (6) extending between four points (A,B,C&D) and crossing itself diagonally in a corner to corner-fashion in the central portion of the ruler, which ruler consists of two flexible parts, a ruler body (1) and a finger rail (2) being in slidable engagement by dovetailing (9) and having clamping devices in both ends in the form of a tapped sleeve (3) and a screw (4) in holes (7), whereby, upon imparting upon the two parts a differently curved shape, the two parts may be clamped together showing a rise of the arch of the ruler, so that the ruler will more easily be pulled over the surface of the drawing-board.The central portion of the finger rail (2) may be removed, whereby the cord (6) may cross itself in this cut away-area (8). Such cord will not hamper the draftsman and will still be easily accessible for check and repair.

Abstract: A braking assembly adapted for attachment to the extremity of a drafting parallel and to the underlying drafting table utilizes a stationary tensioned strand which engages locking means on the drafting parallel. The braking effect is secured by depressing a movable arm which urges a resilient pad into gripping engagement of the strand.

Abstract: A navigation position plotter for determining the navigation coordinates of a point on a navigation chart and plotting the position of a point on the navigation chart. A plate bearing navigation scales divided into increments between two spaced grid lines on the navigation chart is mounted on a frame. A first plotting bar is movably mounted on the frame. A second plotting bar is pivotally mounted on the frame and intersects the first plotting bar. The frame is position over the chart such that the navigation coordinate increment underlying the second plotting bar can be read after the first and second plotting bars have been moved into intersecting relationship over the point to be plotted.

Abstract: A pickup carriage drive for a video disc player comprises a selective-activated motor mounted on a pickup carriage. A drive cord is strung between a pair of anchor points disposed in the player, and has a portion wrapped around the output shaft coupled to the drive motor. The motor, when energized, drives the carriage to follow the pickup stylus across the record during playback.

Abstract: A parallel-ruling straightedge assembly having a base member adapted to be translated over a drafting surface, a first straightedge member of a transparent acrylic material extending along one longitudinal edge of the base member and adapted to provide a drawing edge, and a second edge member of metallic material extending along an opposing longitudinal edge of the base member and having an edge adapted to provide a guide for a cutting blade for use in stripping sheet material.

Abstract: A drafting board tray for use in a drafting board having a cable guide track mounting for use with a straight edge assembly slideably adjustable on the cable guide track. The tray is disclosed to be pivotally attached and pivotally adjustably positionable at each end to two base mounts which are slideably adjustable on the cable guide track.

Abstract: A drafting aid comprising a flat board, the board having two straight parallel edges and guide surfaces at the parallel edges. A flexible member passes about the board and over the guide means. The flexible member includes resilient tension members extending between the end edges thereof to form a taut member about the board.

Abstract: Disclosed is apparatus for determining distances along a direction in a plane. A base is constrained to translational movement along the direction by a guide system. An indicator is connected to the guide system to move relative to the base corresponding to movement of the base along the direction. In the particular embodiment disclosed, a parallel bar is provided with a moveable scale whereby the movement of the bar may be measured by determining the extent of movement of the indicator. A method disclosed for determining distances includes positioning a moveable scale in relation to a base equipped with an indicator identifying the position of the base. A reference marker may be used to identify the position along the scale the indicator is to assume when the base has been moved a desired distance.