Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B43—WRITING OR DRAWING IMPLEMENTS; BUREAU ACCESSORIES
  • B43L—ARTICLES FOR WRITING OR DRAWING UPON; WRITING OR DRAWING AIDS; ACCESSORIES FOR WRITING OR DRAWING
  • B43L11/00—Non-circular-curve-drawing instruments
  • B43L11/02—Non-circular-curve-drawing instruments for drawing conic sections
  • B43L11/04—Non-circular-curve-drawing instruments for drawing conic sections for drawing ellipses
  • B43L11/05—Non-circular-curve-drawing instruments for drawing conic sections for drawing ellipses with gears

Definitions

• the present invention relates to the instruments used for drawing and more particularly the compasses for drawing ellipses.
• the compass object of the present invention allows to re ⁇ mediate all these drawbacks. It is of the type with a single eccentric and a single .biellette whose position can be easily adjusted by a retractable screwdriver rod, which can reach the adjustment screw of the eccentric only when the tracing point falls on a point of one of the diameters of the ellipse.
• the tracer arm is coupled to the lever which transmits the movements of the eccentric, by a screw allowing a millimeter adjustment of the spacing of said tracer arm relative to the central pivot of the compass.
• the tracer arm is articulated and includes a quick adjustment device located downstream of the millimeter and quick adjustments.
• the tip of the central pivot and the plotter support are telescopic and retractable. They undergo the action of two springs, one flexible to start, the other hard for the end. race. They have ball bearings for their axial and radial guides and needle shoes for their longitudinal linear guidance, but cannot rotate.
• the compass has three feet which support the whole instrument, so that the user can let go of it and pay attention only to the adjustments which it maneuver- thus more easily.
• the feet are foldable and can be brought, by rotary movement, one against the other to allow the compass to be stored in a small volume.
• the compass is equipped, at its upper part, with a transverse lever which facilitates the driving of the tracer arm around the central pivot and the adjustment of the tracer to the diameters chosen of the ellipse.
• Figure 1 shows an elevational view of the compass in question.
• Figure 2 is a detail view in partial section of the head for transmitting the movements of the tracer arm.
• Figure 3 is a detail view in elevation section of the support. the tracing tip.
• Figures 4 and 5 show two variants of the support for the tracing tip.
• Figure 6 is a detailed sectional view of part of the central pivot and the toggle.
• Figure 7 shows the detail of the coupling of the tracer arm to the movement transmission lever.
• Figure 8 is a detail view of the eccentric drive pinion.
• Figure 9 shows the detail in perspective of the organs for controlling the movements of the transmission lever.
• Figure 10 is a detail view of the eccentric slide and its adjusting screw.
• Figure 11 shows the perspective detail of an extension system of the distance and the length of the feet of the compass.
• Figure 12 is a perspective view showing the detail of one snap of the feet on the motion control head.
• the drive shaft 1 has a ridged surface 2 and. a cap 3 which serves to hold the compass and a lever 4 which facilitates tracing.
• the axis 1 joins the control head 5, of which it is integral, crossing a dome 'transparen ⁇ te 6 and taking support against a spring 7 which is housed there.
• a second dome 8 encloses the control head 5 and the transmission members described below. Between the two coupo- les 6 and 8 is mounted a socket 9 made integral with the dome 6 by means of a screw 10 and comprising the articulation 11 of a foot 12 whose lower ends is fitted with a sheath 13 for a tip 14 blocked by a screw and a knurled 15.
• the second dome 8 is fixed to the bush 9 by means of a shouldered washer 16 and a screw 17.
• the sleeve 9 can slide two superimposed rings 18 respectively 19; that 18 comprising the articulation 20 of a second leg 21; that 19 comprising the articulation 22 of a third foot 23.
• the exact positioning of the three feet 12, 21 and 23 in a triangle as illustrated in FIG. 1, is achieved by means of a plate 24, fixed at 25 of FIG. 12, comprising two lugs 26, respectively ent 27 which can penetrate into two notches 28, respectively 29 made in the rings 18, respectively 19.
• the control head 5 drives, by an axis 30, a pinion 31 which meshes with a toothed crown 32 cut inside the sleeve 9.
• the axis 30 carries a second pinion
• the slide 37 of the pin 36 is moved by a screw 45, actuated by one.
• ige screwdriver 46 passing through the mounting piece 42 and being able to affect a back-and-forth movement combined with a rotational movement illustrated by the arrows shown in FIG. 2.
• the control head is extended by a pivot 47 comprising a toggle consisting of two plates 49 and 50 enclosing a spacer 48 fixed by rivets 51 and 52 and in which slides the centering tip 53 also guided by the tube 54 that forms the assembly of the two plates 49 and 50.
• the slide between the tip 53 takes place against two springs 55, respectively 56, of which that 55 is more flexible and the other 56 at the end of the race more hard.
• the axis 57 of the toggle joint serves as an articulation for a tracer bra 58 and a transmission lever 59 coupled to the bar 38 by a lug 60 which it comprises, engaged in an oblong slot 61 cutting the end of the lever as
• the bar 38 for transmitting the movement back and forth to the lever 59 is guided by a groove hollowed out in the mounting plate 43.
• the tracer arm 58 and the transmission lever 59 are coupled by a threaded rod 62 taking nuts in two joints 63 of the arm 58 and 64 of. lever 59 and whose end 65 is striated for the operation of 'said screw which allows the millimeter adjustment of the distance between the centering tip 53 and cell 66 for tracing Figure 1.
• the hinge 63, crossed by the threaded rod 62 allows the lever 67 to quickly adjust the spacing between the two elements 53 and 66.
• the articulated part 68 of the arm 58 supports, by means of the plate 70 which it retains clamped by means of a screw, a cylindrical body 71 in which a fur 72 is mounted fixed by a screw 78 and hollowed out by two longitudinal grooves 73, respectively 74 in which are guided two studs 75, respectively 76 of a tube '77 holding prisoner by means of a screw 79 the mechanical pencil 80 with, its lead or stylus 66.
• the tube 77 movable in the fur 72, is engaged the head 81 of a rod 82 with wheel 83, transversing the plug 84 covering the cylindrical body 71.
• This rod undergoes the action of a spring 85 at l 'against which it can act ⁇ as well as on.the tube 77. by means of the washer 81 and a transverse pin 86.
• FIG. 4 _ A variant of this device is shown in FIG. 4 _ •
• the rod 82 is mounted in a triangular slide 87 guided by needle shoes 88 and made integral with the mechanical pencil or plotter holder 80.
• This assembly allows the ent marker to slide up and down under the action of the tig-e 82 following the chosen position but prevents it from turning on itself.
• Several superimposed pins 89 passing through the rod 82 make it possible to choose the position of the tracer relative to the sheet of paper on which the elelysis must be traced.
• FIG. 11 represents an extension device for the feet of the compass.
• Each ring 18 and 19 has a flat nose 95 which extends radially and on which a slide 96 can slide, locked by a screw 97 and forming an articulation 98 for a bent piece 99 playing the role of slide for the slide that each foot of the compass locked by a screw 100.
• Figure 8 shows the detail of the pin 36 driven by the pinion of the pinion 34.
• the groove 36a dug at the base of the Ion touri allows adjustment and retention of the slide 37 under the action of the screw 45 which passes through it.
• the operation of the compass takes place in the following manner.
• the central point 53 is planted in the center of the ellipse to be traced.
• the tracer 66 is adjusted to these diameters by means of the screw 62 e of the screwdriver rod 46, all without the lead or stylus 66 touching the paper but while being close enough for precise and convenient adjustment.
• the plotter By pressing on the cap 3, the plotter is brought into contact with the paper and it suffices to cause the rotation of the control head 5 by means of the lever 4. Thanks to the fixed toothed crown 32, the rotation of the head 5 controls that in ⁇ verses pinions 31 and 33, the latter causing the rotation of the pinion .34 in the direction initially printed on the head 5 by the lever 4.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Toys (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=9270519

Family Applications (1)

Country Status (3)

Cited By (1)

Citations (3)

• 1982
  • 1982-01-27 FR FR8201522A patent/FR2520299A1/fr not_active Withdrawn
• 1983
  • 1983-01-27 EP EP19830900490 patent/EP0099390A1/de not_active Withdrawn
  • 1983-01-27 WO PCT/FR1983/000021 patent/WO1983002588A1/fr unknown

Patent Citations (3)

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